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81.
Two hundred and twenty strains of Campylobacter jejuni (70 human, 51 canine and 99 chicken strains) were isolated from September 2003 to September 2004 in northern Taiwan. These strains were subtyped by PCR-RFLP analysis of the flagellin (FlaA) gene. On the basis of restrictive digest, six types were identified with AfaI, seven types with MboI and five types with HaeIII. With the combination of these three enzymes, 47 distinct PCR-RFLP patterns were observed-25 each from human and chicken isolates, and 9 from canine isolates. In human strains, the most frequently occurring types were Cj-28 (14.3%), Cj-17 (10%), Cj-16 (8.6%), Cj-37 (7.1%) and Cj-46 (7.1%). In canine strains, the most prevalent types were Cj-1 (33.3%), Cj-26 (19.6%), Cj-3 (15.7%), Cj-2 (9.8%) and Cj-10 (9.8%). In chicken strains, the most frequently occurring types were Cj-46 (40.4%), Cj-29 (9.1%), Cj-45 (7.1%) and Cj-41 (5.1%). The results suggest that poultry is a source, but not the sole source, of C. jejuni infection in humans. Two RFLP types, Cj-17 and Cj-37, frequently occurring in human isolates in this study have also been found to be prevalent in human isolates in Japan, China and the Czech Republic, indicating a possible international clonal spread.  相似文献   
82.
Snake or honeybee envenomation can cause substantial morbidity and mortality, and it has been proposed that the activation of mast cells by snake or insect venoms can contribute to these effects. We show, in contrast, that mast cells can significantly reduce snake-venom-induced pathology in mice, at least in part by releasing carboxypeptidase A and possibly other proteases, which can degrade venom components. Mast cells also significantly reduced the morbidity and mortality induced by honeybee venom. These findings identify a new biological function for mast cells in enhancing resistance to the morbidity and mortality induced by animal venoms.  相似文献   
83.
To investigate whether the regulation of garlic allyl sulfides on biotransformation enzyme expression is tissue-specific, the expression of cytochrome P450 2B1 (CYP 2B1) and the placental form of glutathione S-transferase (PGST) in liver, lung, and intestine, which are the three major organs responsible for drug metabolism, was examined. Rats were orally administrated 0.5 or 2 mmol/kg BW diallyl sulfide (DAS) or 0.5 mmol/kg BW diallyl disulfide (DADS) or diallyl trisulfide (DATS) three times per week for 6 weeks. The final body weights and the body weight ratio of liver and lung were not changed by any of these three allyl sulfide treatments as compared to the control rats. An 11- and 12-fold increase of 7-pentoxyresorufin O-dealkylase (PROD) activities was noted in rats treated with 0.5 or 2 mmol/mg BW DAS, respectively, as compared with the controls (P < 0.05). In contrast, DADS and DATS significantly increased hepatic PGST activity toward ethacrynic acid by 30 and 40%, respectively, as compared with the control rats (P < 0.05). An increase in PGST activity was only noted at 2 mmol/kg BW DAS group (P < 0.05). In addition, similar increases in PGST activity due to DADS and DATS were also noted in lung and jejunum tissue (P < 0.05). Immunoblot assay shows that the changes in CYP 2B1 and PGST proteins due to the three garlic allyl sulfide treatments on liver, lung, and jejunum were consistent with those observed for PROD and PGST activities. Northern blot further revealed that the DADS and DATS increased PGST mRNA levels in both liver (2.9- and 3.0-fold, respectively) and lung (4.1- and 2.6-fold, respectively) and DAS dose-dependently increased CYP 2B1 mRNA levels in the liver. Garlic allyl sulfides differentially induced CYP 2B1 and PGST expression, and this up-regulation of these two biotransformation enzymes is tissue-specific.  相似文献   
84.
The purpose of this study was to evaluate the efficacy and toxicity of a CCNU and vinblastine chemotherapy protocol for canine mast cell tumours. Fifty-seven tumours in 56 dogs were evaluated, 37 had macroscopic disease and 20 had microscopic disease. A 57% response rate was seen in dogs with macroscopic disease for a median duration of 52 weeks. Dogs with macroscopic disease had a median progression free survival time (PFST) of 30 weeks and a median overall survival time (OST) of 35 weeks. Dogs with microscopic disease had a median PFST of 35 weeks and a median OST of 48 weeks. Toxicity was recorded in 54% of the dogs treated, with the majority of events being mild. This chemotherapy protocol appears to be well tolerated and should be considered for canine mast cell tumours.  相似文献   
85.
Tsai HJ  Tseng CH  Chang PC  Mei K  Wang SC 《Avian diseases》2004,48(3):512-521
To understand the genetic variations between the field strains of waterfowl parvoviruses and their attenuated derivatives, we analyzed the complete nucleotide sequences of the viral protein 1 (VP1) genes of nine field strains and two vaccine strains of waterfowl parvoviruses. Sequence comparison of the VP1 proteins showed that these viruses could be divided into goose parvovirus (GPV) related and Muscovy duck parvovirus (MDPV) related groups. The amino acid difference between GPV- and MDPV-related groups ranged from 13.1% to 15.8%, and the most variable region resided in the N terminus of VP2. The vaccine strains of GPV and MDPV exhibited only 1.2% and 0.3% difference in amino acid when compared with their parental field strains, and most of these differences resided in residues 497-575 of VP1, suggesting that these residues might be important for the attenuation of GPV and MDPV. When the GPV strains isolated in 1982 (the strain 82-0308) and in 2001 (the strain 01-1001) were compared, only 0.3% difference in amino acid was found, while MDPV strains isolated in 1990 (the strain 90-0219) and 1997 (the strain 97-0104) showed only 0.4% difference in amino acid. The result indicates that the genome of waterfowl parvovirus had remained highly stable in the field.  相似文献   
86.
1. The effect of lactic acid marination at 5°C on post mortem changes in breast muscle pectoralis major of spent layer Tsaiya duck was studied.

2. Myofibrils were prepared from 0.1 M and 0.2 M lactic acid marinated muscle and control (non‐marinated samples) sampled at 0, 1, 3, 7 and 14 d post mortem.

3. Changes in myofibril fragmentation index (MFI), myofibrillar proteins and Z‐line structure were examined.

4. Marination of duck breast muscle in lactic acid at 5°C enhanced fragmentation of myofibrils and degradation of myofibrillar proteins and Z‐line structure as compared to control samples.

5. In summary, lactic acid marination at 5°C can accelerate the post mortem degradation of myofibrils in Tsaiya duck breast muscle.  相似文献   

87.
在田间的小麦丛矮病非典型病株申常常分离到北方禾谷花叶病毒(NCMV)及玉米粗缩病毒(MRDV)两种病原物。单独用前者接种,仅表现小麦丛矮症,单独用后者接种,仅表现小麦蓝矮症,即植株矮化、暗绿、分蘖减少,叶坚挺。两者混合侵染时,往往表现两者的混合症状,但以何种病毒占优势而倾向于优势病毒的症状。典型丛矮症植株中电镜检出弹状病毒粒体,40—70×270—400nm尺度与日本报导的稍异。典型丛矮病株中不存在玉米粗缩病毒的粒体。小麦丛矮病毒很可能是北方禾谷花叶病毒的一种地方性株系。  相似文献   
88.
This study investigated gender, caponization and exogenous estrogen effects on lipids, bone and blood characteristics in Taiwan country chickens. Thirty male chickens were caponized at 8 weeks (capons); 15 capons were injected with estrogen (5 mg/bird estradiol 3‐benzoate) every 2 weeks from 8 to 28 weeks, and 15 sham‐operated male (shams) chickens and 15 females were selected for this trial. The results showed that the shams had lower relative abdominal and chest subcutaneous fat than females (P < 0.05). The estrogen‐treated capons had greater relative abdominal and chest subcutaneous fat than shams and capons (P < 0.05), which might result from higher blood very low‐density lipoproteins and triacylglycerol concentrations (P < 0.05). Caponization could dramatically increase relative abdominal fat (506%; P < 0.05). The shams had higher tibia weight and biomechanical properties, such as maximum bone strength and bending moment values than the capons (P < 0.05). Tibia biomechanical properties were reduced by estrogen treatment (P < 0.05). The females obtained the lowest biomechanical value in all treatments (P < 0.05). Histological examination revealed cavity formation in the cortical bone of estrogen‐treated capons and female chickens, which suggested that estrogen reduced bone biomechanical properties by destroying its structural integrity.  相似文献   
89.
90.
Hemorrhagic fever with renal syndrome (HFRS) comprises a variety of clinically similar diseases of viral etiology that are endemic to and sporadically epidemic throughout the Eurasian continent and Japan. Although HFRS has not been reported in North America, viruses that are antigenically similar to HFRS agents were recently isolated from rodents in the United States. Examination and comparison of eight representative isolates from endemic disease areas and from regions with no known associated HFRS indicate that these viruses represent a new and unique group that constitutes a separate genus in the Bunyaviridae family of animal viruses.  相似文献   
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