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1.
Adherence of streptococcal isolates from cattle and horses to their respective host epithelial cells 总被引：2，自引：0，他引：2
P Valentin-Weigand G S Chhatwal H Blobel 《American journal of veterinary research》1988,49(9):1485-1488
Adherence of Streptococcus dysgalactiae isolates from cattle and S equi isolates from horses to their respective host epithelial cells was compared with the adherence of S pyogenes to human epithelial cells. The adherence was quantitatively determined by use of fluorescein-labeled streptococci. All 3 streptococcal species adhered selectively to their respective host cells. The mechanism of adherence was evaluated by binding studies with adhesive plasma protein, fibronectin. Although all 3 streptococcal species bound fibronectin, S dysgalactiae and S equi interacted preferentially with a 210-kilodalton (kD) C-terminal fragment of fibronectin, whereas S pyogenes bound only a 29-kD N-terminal fragment. A synthetic peptide Gly-Arg-Gly-Asp-Ser, representing the host cell attachment site of fibronectin, partially inhibited the binding of fibronectin and of its 210 kD fragment to S dysgalactiae, but not to S equi. The binding of fibronectin and its 29-kD fragment to S pyogenes was not inhibited by Gly-Arg-Gly-Asp-Ser. These differences in binding activities corresponded to the ability of fibronectin to mediate the adherence of the streptococci to the epithelial cells: fibronectin strongly inhibited the adherence of S pyogenes and S equi to the epithelial cells, but only weakly inhibited that of S dysgalactiae. 相似文献
2.
Interaction of sub-epithelial connective tissue components with Staphylococcus aureus and coagulase-negative staphylococci from bovine mastitis 总被引：4，自引：0，他引：4
Staphylococcus aureus and coagulase-negative staphylococci (CNS) isolated from bovine mastitis were examined for their ability to interact with 125I-labelled fibronectin, fibrinogen and type II collagen. Their relative surface hydrophobicity and production of extracellular capsule were also investigated. Almost all S. aureus strains bound fibronectin (mean value 23%), fibrinogen (mean value 12%) and type II collagen (mean value 16%). CNS bound fibronectin (mean value 6%) and type II collagen (mean value 7%), but not fibrinogen (mean value 2%). The specificity of binding of these proteins to S. aureus strain F1440 and to coagulase-negative Staphylococcus chromogenes strain BO52 was studied by adding an excess of unlabelled proteins. Fibronectin and collagen binding were observed to be specific, varying between 50 and 75%, whereas the specificity of fibrinogen binding to S. aureus strain F1440 was lower (26%). Most of the S. aureus strains (63%) showed very high surface hydrophobicity (autoaggregation) or lower hydrophobicity (29% of the strains) and the rest were hydrophilic. None of the CNS strains autoaggregated, 44% were classified as hydrophilic strains. Hydrophilic strains (except the reference strains) did not show extracellular capsule production. However, the encapsulated (reference) strains showed low binding to these proteins as compared to their unencapsulated variants. Pre-treatment of S. aureus strain F1440 and S. chromogenes strain BO52 with trypsin decreased their fibronectin binding capacity and surface hydrophobicity, whereas pre-treatment with bovine milk (except on collagen binding to strain F1440) did not significantly affect binding to these proteins. These data indicate that S. aureus and CNS isolated from bovine udder infection have the ability to bind to tissue matrix and plasma proteins which may be exposed in the traumatized or toxin-damaged udder epithelial lesions. 相似文献
3.
Sixty-two animal enterococci were examined for their binding of bovine fibrinogen, porcine fibronectin, bovine lactoferrin, bovine apotransferrin and human holotransferrin in the particle agglutination assay (PAA). Individual strains expressed binding of selected glycoproteins to various degrees (0, 1, 2, 3), whereas bovine fibrinogen binding of enterococci from goats, rabbits and rodents was the strongest (3) in general. Porcine fibronectin was bound weakly (1 or 2) by enterococci from horses, dogs, poultry, rabbits and rodents, while most of the goat isolates and half of the dog feed isolates did not bind fibronectin (0). Bovine lactoferrin was bound especially by the isolates from rodents and rabbits. Bovine apotransferrin was bound very weakly (1) by only a few isolates. Human holotransferrin was bound to a greater extent than apotransferrin by some isolates from rabbits and rodents. Since multiresistant strains are preferred in our binding studies, enterococci were also examined for their antibiotic resistance pattern. Almost all investigated isolates were resistant at least to one antibiotic. However, some strains displayed resistance to five or six antibiotics of 10 antibiotics tested. In a study of the inhibitory effect of heparin, porcine mucin and hyaluronic acid, the greatest effect was observed after heparin treatment of bacterial cells. These observations, as well as the expression of heparin binding by most strains, may suggest that at least one mode of enterococcal attachment utilizes glycosaminoglycan chains present on the surface of adherent cells. 相似文献
4.
R Baselga B Amorena 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1990,37(7):556-560
A total of 59 mastitis staphylococcic strains were tested for growth agglutination upon supplementation of growth media with ovine and bovine milk whey and mammary secretions from dry cows. Differences were observed when comparing bacterial species or origins (ovine vs. bovine) of bacteria and whey. All of the ovine and bovine S. aureus strains tested, but only 4 among 22 other ovine mastitis staphylococcic strains, showed growth agglutination in Todd Hewitt broth (THB) supplemented with greater than or equal to 30% (v/v) ovine milk whey. None of the strains agglutinated during growth in regular THB medium. Ovine whey had an agglutination induction capacity higher than bovine whey (P less than 0.005), concerning the number of responsive ovine and bovine S. aureus strains. There were no differences between whey samples from different ewes with regard to their capacity to induce agglutination. Ovine S. aureus strains were more responsive than bovine strains of this bacterial species, concerning the number of responsive strains (P less than 0.001) to bovine whey (greater than or equal to 30% in THB), the proportion of responsive strains at low (10%) ovine whey concentration (P less than 0.001), and the strength of reaction (precipitation timing and clump size). Secretions from dry cows systematically induced agglutination in all of the bovine and ovine S. aureus strains tested. 相似文献
5.
Klebsiella strains isolated from the cow and its environment were biochemically and serologically characterized and evaluated for their susceptibility to normal bovine serum. Thirty-one different biotypes of Klebsiella were identified among 288 cattle and environmental strains. Of these, 56.2% were indole-positive, a greater percentage than expected for Klebsiella. Biotypes 1/1/1 and 5/1/1, most frequently isolated and constituting about 37% of the total isolates, would be considered K pneumoniae by standard biochemical typing procedures. Of 65 cattle and environmental strains studied serologically, 11 serotypes, 14 biotypes, and 29 bioserotypes were identified, indicating the diversity of Klebsiella strains present in the herd. When strains from mastitic milk (n = 19) and the environment (n = 22) were compared, no bioserotype distinction or grouping that related to isolation source was obvious. The predominant bioserotype from both sources was 5/1/1-K35 (21.0% and 22.7% of the strains from mastitic milk and the environment, respectively). The growth inhibition by bovine serum of strains isolated from mastitic milk, the environment, and udder skin was similar. However, strains isolated from the mouth and rectum of the cow were significantly (P less than 0.05) more inhibited by serum. 相似文献
6.
We previously showed that Staphylococcus aureus cells adhered mainly to an elongated cell type, present in cultures of bovine mammary gland cells. Moreover, we showed that this adhesion was mediated by binding to fibronectin. The same in vitro model was used here, to study adhesion of other important mastitis pathogens. Like the S. aureus strains, the Streptococcus dysgalactiae strains adhered mainly to elongated cells, which seemed to be mediated by fibronectin binding. In contrast, Streptococcus uberis strains adhered mainly to cubic cells. Since the cubic cells did not express fibronectin and S. uberis cells bound fibronectin less efficiently, the adhesion of S. uberis cells was independent of fibronectin binding. Streptococcus agalactiae strains adhered poorly to both cell types. The specificity and efficiency of adhesion of Escherichia coli strains was strongly strain dependent. None of the S. agalactiae and E. coli strains tested was able to bind fibronectin efficiently. The results suggest that the different mastitis pathogens have different target cell specificities and use different mechanisms to adhere to cells of the bovine mammary gland. 相似文献
7.
Three gut lactobacilli from piglets (Lactobacillus plantarum L 5, Lactobacillus paracasei L 81, Lactobacillus fermentum L 670) and Lactobacillus casei subsp. pseudoplantarum L.c.) from a calf were examined by microtitre plate binding assay for their lectin-like binding activity after their cultivation on Rogosa agar and in MRS broth. Three ECM (extracellular matrix) molecules (fetuin, porcine fibronectin and porcine mucin) were selected for this assay. Additionally, the effect of heparin on the binding of these three ECM molecules by Lactobacillus strains in microtitre plates was tested. Moreover, haemagglutination tests with pig, cattle, sheep, and hen erythrocytes were performed. However, none of the four Lactobacillus strains examined did react with any of the erythrocytes tested. The differences between individual strains were observed in their binding to immobilised ECM molecules. The best adherent was the Lactobacillus plantarum L5, however, the other three strains showed also good ECM binding. With regard to an influence of cultivation medium on lectin-like binding activity, binding of all ECM molecules was expressed in Lactobacillus paracasei L 81 to significantly higher degree (P < 0.001) after cultivation on Rogosa agar than in MRS broth. Similarly, strains Lactobacillus fermentum L 670 and Lactobacillus casei subsp. pseudoplantarum L.c. displayed significantly higher (P < 0.001) binding of fibronectin and mucin after growth on Rogosa agar in comparison with MRS broth cultivation. However, no significant (on fetuin and fibronectin binding) or opposite effect (on mucin binding) of cultivation medium was observed in Lactobacillus plantarum L 5 strain. The influence of cultivation medium on fetuin binding by Lactobacillus fermentum L 670 was also not significant while Lactobacillus casei subsp. pseudoplantarum L.c. bound fetuin significantly better (P < 0.01) after growth on Rogosa agar. Heparin pretreatment increased the binding of the ECM molecules by the Lactobacillus fermentum L 670 strain significantly (P < 0.001 or P < 0.05) with the exception of porcine fibronectin when the strain was cultivated in MRS broth. This result is important especially in the connection with the previous observations that heparin decreased ECM binding of enteropathogens as staphylococci or clinical enterococcal isolates. Following up on some earlier strain characteristics, these results indicate that the selected lactobacilli are probably suitable for probiotic purposes. 相似文献
8.
模拟发情期（0～6 d）母牛外周血雌激素和孕酮浓度的变化，添加17β-雌二醇和孕酮至TCM-199中，体外培养间情期牛输卵管上皮细胞（BOECs），同时观察了BOECs分泌蛋白（BOEP）、发情期母牛输卵管冲洗蛋白（BOP）和小牛输卵管冲洗蛋白（COP）对小鼠胚胎发育的影响。结果表明：①类固醇激素可以调节和启动体外培养的间情期牛输卵管上皮细胞的分泌活动；②BOEP比BOP和COP能极显著地促进胚胎的分裂和发育（Ｐ<0.001）；③与对照组（未添加外源蛋白质，只添加胎牛血清）相比，BOEP的囊胚形成率极显著低于对照组（Ｐ<0.01），可能是缺乏某些分子量低于10 kD蛋白因子的协同作用，同时30～56kD分泌蛋白的存在，也可能参与了抑制和阻碍胚胎分裂和发育的过程。 相似文献
9.
Ingestion and killing of Streptococcus agalactiae by bovine granulocytes in the presence of natural opsonins 总被引：3，自引：0，他引：3
An enzyme-linked immunosorbent assay (ELISA) demonstrated the presence of naturally acquired antibodies against Streptococcus agalactiae in normal bovine serum (NBS). In milk wheys, ELISA values were much lower than in sera. Pre-colostral calf serum (PCS) was shown to lack antibodies to type II and III S. agalactiae. The opsonic requirements of 10 human and 10 bovine strains were investigated by evaluating the phagocytosis-induced reduction of the incorporation of radiolabeled thymidine by streptococci. Antibodies present in NBS were required for the efficient ingestion of both human and bovine isolates type II by bovine granulocytes. Three out of five type III bovine isolates were opsonized in the absence of specific antibodies (opsonization by PCS) and type II and III bovine isolates did not require complement opsonization. By contrast, inactivation of complement reduced phagocytosis of human isolates and only one type III strain of human origin was opsonized by PCS. These findings suggest that human isolates had higher opsonic requirements. The phagocytic killing of 6 type III strains (5 mastitis isolates and the reference typing strain) was investigated. Opsonization by normal serum enabled bovine blood granulocytes to ingest and kill S. agalactiae. Nevertheless, greater than or equal to 35% of bacteria remained viable at the end of the phagocytosis incubation in 10% NBS. Heat treatment of serum decreased the efficacy of killing for only 3 of the 6 tested strains. An IgG2 fraction of normal adult bovine serum promoted active ingestion, which was still increased in the presence of PCS. Normal wheys displayed large variations in their ability to promote ingestion of S. agalactiae by blood granulocytes. The promoting effect was systematically less than that of serum from the same cow, and this can be related to the lower ELISA values found in wheys. 相似文献
10.
Of 470 Gram-negative facultative anaerobes isolated from cases of bovine mastitis in England and Wales, 422 were identified as Escherichia coli. The characteristics of 237 of these were investigated. Guinea-pig red cell haemagglutinins were possessed by 86% of strains and 12% were resistant to D-mannose. None of the strains tested invaded Vero cells. Haemolysin, Vero toxin and enterotoxin were produced by 5, 0.5 and 1% of strains, respectively. Twenty-two percent were resistant to one or more antibiotics and 4% to sodium arsenate. Transfer ability was possessed by 41% and lysogenic phage by 27% of strains; 62% possessed either one or the other and 12% possessed both. Colicin production was detected in 18% of strains; 5% produced Colicin V. Ninety-nine percent of strains were serum-resistant, while only 6% were able to grow well in bovine serum. A microscopically visible capsule was seen in 75% of strains. All strains possessed at least one of the potential virulence factors or markers studied. Several strains which possessed one characteristic only (mannose-sensitive haemagglutination or serum resistance), possessed one or more large molecular weight plasmids. None of the strains was particularly virulent for chickens following intramuscular inoculation. Of the strains which possessed one virulence characteristic, only those which were serum-resistant were re-isolated from expressed milk following intramammary inoculation of lactating cows. 相似文献
11.
The specificity of the humoral IgG response of cattle naturally or experimentally infected with bovine viral diarrhea virus (BVDV) was studied by radioimmunoprecipitation. Serum samples were tested against radiolabeled lysates of cells infected with cytopathic and noncytopathic biotypes of BVDV. A biotype-specific serologic marker was not detected. The specificity of the IgG induced in cows naturally or experimentally infected with either BVDV biotype was essentially the same. A strong IgG response to the 2 glycoproteins (56 to 58 kilodaltons, [kD] and 48 kD) of both biotypes and to the major polypeptides was induced in infected cells: 118 kD and 80 kD by cytopathic BVDV and only 118 kD by noncytopathic BVDV. The most consistent difference among cattle was the presence of IgG specific for the 37-kD polypeptide. Sequential serum sample collection after spontaneous and induced infections with either BVDV biotype did not indicate specific IgG markers for determining infection history. Sera from cattle with a confirmed diagnosis of mucosal disease and lacking neutralizing antibodies to BVDV usually lacked (greater than 80%) nonneutralizing BVDV-specific IgG. One animal had substantial amounts of IgG to the 80-kD polypeptide. Other cattle had less readily detectable amounts of IgG specific for 80-kD or 37-kD viral polypeptides. 相似文献
12.
Factors affecting the infectivity of lymphocytes from cattle with bovine leukosis virus. 总被引：1，自引：0，他引：1 
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下载免费PDF全文 Peripheral blood mononuclear cells were obtained from 13 bovine leukosis virus infected cattle and inoculated subcutaneously into 29 recipient adult steers to determine (a) the number of mononuclear cells (equivalent amount of blood) necessary to cause infection and (b) factors influencing infectivity of mononuclear cells from bovine leukosis virus-infected animals. A total of 55 inoculations were made. Inoculation of 1 X 10(4), 2 X 10(4) and 5 X 10(4) mononuclear cells caused seroconversion in 12%, 57% and 62% of steers, respectively. No infections occurred with 1 X 10(3) or 2 X 10(3) mononuclear cells. Cattle infected for longer than 24 months and those animals greater than three years of age were more likely to cause infection with 1 to 5 X 10(4) mononuclear cells than were cattle infected for less than 24 months or animals less than three years of age. Lymphocytes from cattle with persistent lymphocytosis caused more infections when 1 X 10(4) or 2 X 10(4) mononuclear cells were inoculated, than did lymphocytes from nonpersistent lymphocytosis cattle; however, both groups were equally infectious when 5 X 10(4) mononuclear cells were inoculated. No differences were found in infectivity of experimentally vs naturally exposed animals. 相似文献
13.
The relationship of seven monoclonal antibodies, putatively to the Bo5 (CD5) antigen, was tested. Five of the mAbs were confirmed to be directed against the Bo5 antigen. Three mAbs, CC29, BLT-1 and 8C11, effectively blocked binding to bovine PBM of mAb CC17, previously reported to be directed against this antigen. MAb 8-3F4 also blocked binding of mAb CC17, but less effectively than the others. MAbs IL-A67 and 79-5 did not inhibit binding of mAb CC17 because of antibody allelic specificity or technical reasons. 相似文献
14.
Leitner G Krifucks O Younis A Heller ED Saran A 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2002,49(7):354-360
The role of Staphylococcus aureus and coagulase-negative staphylococcal exosecretions was tested for its ability to elicit in vitro proliferation of bovine blood lymphocytes, which we determined by means of the 3H-thymidine proliferation assay and by flow cytometry. Exosecretions of 32 field strains of S. aureus isolated from bovine udder infection and one of each of S. intermedius (M2), S. hyicus (M5), S. xylosus (M6) and S. chromogenes (M10) were used. Of the 32 S. aureus bacterial exosecretions, only 14 stimulated bovine mononuclear cells to proliferate. A high degree of association was found when the proliferation indexes were compared with the virulence as determined by intracisternal inoculation. All the six S. aureus strains that were categorized as highly virulent and that were tested in the proliferation assay exhibited a proliferation index > 20, whereas the five S. aureus strains that were categorized as low did not stimulate at all. Cells treated with media or Columbia broth supplemented with 0.1% D-glucose, yeast extract, and 0.5% NaCl (CBs) did not exceed 15% of the T-cells double positive with CD25+, whereas incubation with Con A activated the T-cells to display CD25+ up to 90%. Cells treated with one of the exosecretions that stimulated bovine mononuclear cells to proliferate, stimulated CD3+ and CD4+ T-cells to exhibit CD25+ receptor significantly higher (P < 0.05) than that found in media and CBs treatments, but lower than those found in Con A treatments. The exosecretions that did not stimulate mononuclear cells to proliferate also did not activate T-cells to exhibit CD25+ receptor. Con A activated 74% out of the total CD8+ to exhibit ACT2 receptor and 50% out of the total CD4+ to exhibit ACT3 receptor. A few but not all of the exosecretions that activated the CD25 receptor on T-cells also activated the ACT3 receptor on CD4+ cells. 相似文献
15.
The binding kinetics of radiolabeled Salmonella california 1989/O (mannose-sensitive hemagglutinin-positive [MSHA+]) to immobilized mucus or enterocytes isolated from broiler ceca and inhibition of binding by D-mannose and sodium metaperiodate were characteristic of adherence of mannose-sensitive type 1 fimbriae of bacteria to eukaryotic mannose-containing receptors. Binding by radiolabeled strains 1989/O (in the presence of D-mannose) and S. typhimurium S 7471 N (MSHA-, non-fimbriated) indicated non-specific binding that was characterized by less binding to enterocytes and mucus and lack of inhibition by carbohydrates or prior treatment with sodium metaperiodate. Inhibition of non-specific binding to enterocytes by pretreatment with various enzymes or by the presence of tetramethylurea or p-nitrophenol (known to disrupt hydrophobic interactions) indicate involvement of multiple sites and hydrophobic bonding. Strain-specific outer-membrane preparations inhibited non-specific binding to a greater extent than did lipopolysaccharide, Escherichia coli outer-membrane preparations, or bovine serum albumin. 相似文献
16.
Hasoksuz M Lathrop SL Gadfield KL Saif LJ 《American journal of veterinary research》1999,60(10):1227-1233
OBJECTIVE: To isolate bovine coronaviruses from the respiratory tracts of feedlot cattle and compare antigenic and biological properties of these strains with bovine enteric coronaviruses. ANIMALS: 5- to 8-month-old mixed-breed cattle at 4 feedlots. PROCEDURE: Samples were obtained from the nasal passages for testing. The 13 samples with the highest magnitude of positive values for bovine coronavirus (BCV) were cultured. Ten strains of bovine respiratory coronavirus (BRCV) were adapted successfully to serial passage. After observation of cytopathic effects (CPE) and confirmation of BRCV by immune electron microscopy and immunofluorescence testing, cell culture-adapted strains were cloned by limiting dilution. These isolates then were compared with a panel of bovine enteric coronaviruses (BECV), using hemagglutination (HA), receptor-destroying enzyme activity (RDE), hemagglutination inhibition (HI), and virus neutralization (VN) assays. Antigenic relatedness values then were calculated. RESULTS: The BRCV were detected in 105 of 488 (21.5%) of the cattle tested. Of 13 strains tested, 10 were isolated in cell culture. Six of the BRCV strains were similar to 2 strains obtained from neonatal calves with diarrhea and 2 strains from adult cattle with winter dysentery. The other 4 BRCV isolates had high RDE activity against mouse erythrocytes but differed from other strains of BECV Nine of 10 BRCV isolates had properties similar to the 2 BECV subtypes. CONCLUSIONS AND CLINICAL RELEVANCE: The BRCV can be isolated from nasal passages of cattle entering feedlots. Most BRCV were similar to BECV strains, although a few had unique properties. Vaccines developed to protect against enteric strains also may protect against respiratory tract strains. 相似文献
17.
Vimercati C Cremonesi P Castiglioni B Pisoni G Boettcher PJ Stella A Vicenzoni G Moroni P 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2006,53(9):423-428
We investigated 116 Staphylococcus aureus isolates from cows, goats and sheep with intramammary infections (IMI) in Italy to provide information about the spread of enterotoxigenic strains and to compare strains isolated from different ruminant species. The isolates were typed by restriction fragment length polymorphism (RFLP) analysis of the coagulase (coa) gene, by analysis of polymorphisms of the X region of protein A (spa) gene and by detection of genes encoding enterotoxins (sea, seb, sec, sed, see, seg, seh, sei, sej and sel). Seven different coa types and 12 different spa types were distinguished. On the basis of polymerase chain reaction-RFLP, 29 different coa subtypes were identified. Two different coa subtypes accounted for 49% and 67% of bovine and ovine isolates respectively. Only seven coa subtypes were observed in isolates from more than one host species and no coa subtype was present in isolates from all three ruminant species. Furthermore, 85 of the isolates (73%) harboured at least one enterotoxin gene (se) with a predominance of sea, sed and sej among isolates from bovine IMI, and sec and sel among isolates from caprine and ovine IMI. Comparing the S. aureus isolates on the basis of gene polymorphisms and presence of se genes, significant differences were found in distributions of genotypes among isolates from cows, goats and sheep. 相似文献
18.
The minimum inhibitory concentration (MIC) of ten antimicrobial drugs for 287 S. aureus strains recently isolated from bovine mastitic milk in different herds all over Sweden was determined. The minimum bactericidal concentration (MBC) of benzylpenicillin for 20 strains was determined. Thirty strains (10%) produced beta-lactamase. All strains were susceptible to oxacillin and neomycin, and more than 90% to streptomycin, trimethoprim-sulphamethoxazole chloramphenicol, erythromycin and tetracycline, whereas all were resistant to sulphamethoxazole. None of 20 strains investigated was tolerant to benzylpenicillin. However, S. aureus strains, isolated from bovine milk, should be tested for beta-lactamase production prior to treating mastitic cases with beta-lactam drugs. 相似文献
19.
20.
O Holmberg 《Acta veterinaria Scandinavica》1975,16(3):411-419
Both the human and the bovine international sets of phages were used for typing of 372 bovine Staphylococcus aureus (Sa) strains, whereas the bovine set alone was used for typing of a further 1183 strains. In addition, 338 of the strains were tested for antibiotic sensitivity. Out of 372 Sa strains 85.5% could be typed with the human and 89.8% with the bovine phage set. Of all the 1555 Sa strains used 92.4% were lysed by the bovine phage set. Several phage types can be present in one and the same herd and some of them can predominate. Resistance to most of the tested antibiotics was very low. The incidence of resistance to penicillin and ampicillin was 10.0% and 4.4% respectively. 相似文献