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排序方式: 共有286条查询结果,搜索用时 15 毫秒
11.
Ainsworth DM Erb HN Eicker SW Yeagar AE Viel L Sweeney CR Lavoie JP 《Journal of the American Veterinary Medical Association》2000,216(8):1282-1287
OBJECTIVE: To determine whether results of physical or radiographic examination or biochemical analyses in adult racehorses with primary lung abscesses were associated with ability to race following treatment. DESIGN: Multiple-center retrospective study. ANIMALS: 25 Standardbreds and 20 Thoroughbreds. PROCEDURE: Medical records of horses with a primary lung abscess that were admitted to any of 4 veterinary teaching hospitals were reviewed. Results of physical examination, laboratory testing, and thoracic radiography were reviewed. Racing performance after treatment was compared with performance before illness and with performance of the general population of racehorses of similar age, sex, and breed. RESULTS: 23 of 25 Standardbreds and 13 of 20 Thoroughbreds raced after diagnosis and treatment of a lung abscess. Most horses had a solitary abscess in the dorsal to caudodorsal lung fields. Results of initial physical examination, biochemical analyses, and culture and identification of the microbial isolate were not associated with whether a horse returned to racing. For horses that had raced prior to the illness, race performance after treatment of the lung abscess was not significantly different from performance before the illness. CONCLUSIONS AND CLINICAL RELEVANCE: On the basis of racing performance in those horses that resumed racing after treatment, long-term residual lung damage did not develop in horses with primary lung abscesses that were treated appropriately. It is not known whether horses that recovered would be more likely to bleed from the site of a prior infection when resuming strenuous exercise and whether lung abscesses contributed to a failure to resume racing. 相似文献
12.
Stokol T Brooks MB Erb HN 《Journal of the American Veterinary Medical Association》2000,217(11):1672-1677
OBJECTIVE: To determine the effect of citrate concentration (3.2 vs 3.8%) on coagulation tests in dogs. DESIGN: Original study. ANIMALS: 30 clinically healthy dogs and 12 dogs with hereditary hemostatic disorders. PROCEDURE: Blood was collected from all dogs directly into collection tubes containing 3.2 or 3.8% buffered citrate. Prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen concentration were measured by use of 3 clot-detection assay systems (2 mechanical and 1 photo-optic). Factor VIII and factor IX coagulant activities (FVIII:C and FIX:C, respectively) were determined by use of a manual tilt-tube method and a mechanical clot-detection device. RESULTS: Significant differences were not detected in median PT, fibrinogen concentration, FVIII:C, or FIX:C between 3.2 and 3.8% citrate for any assay system. A significant prolongation in aPTT for 3.2% citrate, compared with 3.8% citrate, was found in 1 mechanical system. CONCLUSIONS AND CLINICAL RELEVANCE: Citrate concentration does not significantly affect results of most coagulation assays, regardless of assay system. The aPTT was mildly influenced by the citrate concentration, although this was animal-, instrument-, and reagent-dependent. The choice of 3.2 or 3.8% citrate as an anticoagulant for coagulation tests has minimal influence on assay results in healthy dogs or dogs with hereditary hemostatic disorders. 相似文献
13.
We simulated the effect of extending the voluntary wait period by 100 days on disorder-frequency measures that were based on cow-years (from lactations completed during the 4-year simulation horizon), metric tons of milk yield, and lactational incidence risks. A dynamic stochastic discrete-event simulation model that focuses on clinical and subclinical intramammary infections (IMI), plus clinical metabolic (left-displaced abomasum, ketosis, milk fever) and reproductive (cystic ovarian disease, dystocia, retained placenta, twinning, uterine infection) disorders in dairy herds was used. Although the voluntary wait period was increased by 100 days (50 vs. 150), the predicted difference in simulated days to conception was only 89 days for the extended voluntary wait-period group (which we attributed to higher fertility later in lactation). Herds that had a voluntary wait period of 150 days (compared to the control herds' voluntary wait period of 50 days) were predicted to have significantly lower rates of metabolic and reproductive disorders and clinical mastitis on both cow-year and milk-yield bases. Simulated control herds, on average, produced 8539 kg of milk in an average lactation of 325 days and simulated herds with a 150-day voluntary wait period 10893 kg of milk in an average lactation of 409 days. There was a significantly lower predicted rate and risk of culling for reproductive failure in the extended voluntary wait period group. The predicted lactational incidence risks for subclinical IMI were 18% higher for the extended voluntary wait period group - but extending the voluntary wait period by 100 days was predicted not to increase the risk of any of the other 10 disorders. 相似文献
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15.
H. G. Allore D. J. Wilson H. N. Erb P. A. Oltenacu 《Preventive veterinary medicine》1998,33(1-4):11-29
The data for this cross-sectional retrospective study are from surveys of 65 dairy-cattle herds in central New York, USA sampled between February, 1993 and March, 1995. The objective was to identify probability distributions of logarithmically transformed somatic-cell counts (linear score) for use in a simulation model of mastitis and milk quality. Probability density functions were estimated using maximum-likelihood estimators for the linear score of individual-cow compositemilk samples culture negative and culture positive for the pathogens Streptococcus agalactiae, Streptococcus non-agalactiae, Staphylococcus aureus, and coagulase-negative staphylococci for the complete dataset and by bulk-tank somatic-cell count group (< 500 000, ≥ 500 000 SCC/ml). Based on the rankings of three goodness-of-fit tests (Anderson-Darling, Kolmogorov-Smirnov and x2), the Weibull distribution (among the three top-ranking distributions for 14 out of 15 cases) may be used to model the individual-cow linear-score response by culture-result-specific bulk-tank somatic-cell count group. A β distribution was among the three top-ranking distributions for nine out of 15 culture-result-specific bulk-tank somatic-cell count groups and has a logical relationship to linear score because it is defined on a fixed interval. On the other hand, the normal distribution had a poorer fit than the Weibull and at least two other distributions for all culture negative and coagulase-negative staphylococci samples. We do not assume that the underlying biological processes are fully explained by either Weibull or β distribution—but modelling the linear score for the above culture results with these distributions provided an adequate fit to the survey data, reduced the need for two-sided truncation that open intervals needed, and had errors that did not appear to be systematically positive or negative. 相似文献
16.
S A Center B H Baldwin H N Erb B C Tennant 《Journal of the American Veterinary Medical Association》1985,187(9):935-940
The clinical usefulness of measuring serum bile acid concentrations as a diagnostic test for hepatobiliary disease, was examined in 150 dogs that were suspected of having hepatic disease. Serum values of total bilirubin (TB), alkaline phosphatase (ALP), alanine transaminase (ALT), and albumin were also measured. Fasting serum bile acid (FSBA) values were determined, using a solid-phase radioimmunoassay for total conjugated bile acids or a direct enzymatic spectrophotometric method. A definitive diagnosis was established by histologic examination of the liver. On the basis of histologic findings, dogs were assigned to groups (1 to 8, respectively) including: extrahepatic bile duct obstruction, cirrhosis, portal systemic vascular anastomosis (PSVA), hepatic necrosis, intrahepatic cholestasis, steroid hepatopathy, neoplasia, and secondary disease. Dogs in group 8 had no morphologic evidence of hepatobiliary disease or had mild hepatic lesions. Test efficacies of FSBA, TB, ALP, ALT, and albumin were expressed using 4 indices: sensitivity, specificity, and positive-predictive and negative-predictive values. The diagnostic efficacy of FSBA was examined alone and in combinations with the other tests. There was wide overlapping of FSBA values among dogs in groups 1 to 7, and there was wide overlapping of ALT and ALP values among dogs in all groups. The specificity of FSBA for the diagnosis of liver disease exceeded 90% at values greater than or equal to 30 mumol/L and reached 100% at greater than or equal to 50 mumol/L. Individual liver tests with the best sensitivity for each group were:FSBA and ALP for extrahepatic bile duct obstruction; FSBA for cirrhosis and PSVA; ALT for hepatic necrosis; and ALP for intrahepatic cholestasis, steroid hepatopathy, and neoplasia. Combinations of tests with the best sensitivity for each group were: FSBA + ALP for extrahepatic bile duct obstruction; FSBA + ALT for cirrhosis and PSVA; FSBA + ALT and TB + ALT for hepatic necrosis; and FSBA + ALP for intrahepatic cholestasis, steroid hepatopathy, and neoplasia. Individual tests had the best sensitivity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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18.
A methylaspartate cycle in haloarchaea 总被引:1,自引:0,他引:1
Access to novel ecological niches often requires adaptation of metabolic pathways to cope with new environments. For conversion to cellular building blocks, many substrates enter central carbon metabolism via acetyl-coenzyme A (acetyl-CoA). Until now, only two such pathways have been identified: the glyoxylate cycle and the ethylmalonyl-CoA pathway. Prokaryotes in the haloarchaea use a third pathway by which acetyl-CoA is oxidized to glyoxylate via the key intermediate methylaspartate. Glyoxylate condensation with another acetyl-CoA molecule yields malate, the final assimilation product. This cycle combines reactions that originally belonged to different metabolic processes in different groups of prokaryotes, which suggests lateral gene transfer and evolutionary tinkering of acetate assimilation. Moreover, it requires elevated intracellular glutamate concentrations, as well as coupling carbon assimilation with nitrogen metabolism. 相似文献
19.
Malone EK Rassnick KM Bailey DB Kiselow MA Erb HN 《Veterinary and comparative oncology》2011,9(3):225-231
Questionnaires completed by pet owners are widely used instruments to monitor adverse gastrointestinal (GI) effects in the owners' animals undergoing chemotherapy and for reporting toxicoses in clinical trials; however, no questionnaires have been formally evaluated. This study compares two questionnaire-based evaluations of adverse GI events: a basic, open-ended questionnaire and a detailed questionnaire modelled after the grading in the Veterinary Co-operative Oncology Group-Common Terminology Criteria for Adverse Events (VCOG-CTCAE). Owners completed both questionnaires after their dog or cat received moderately emetogenic chemotherapy. Results were used to derive toxicity grades for anorexia, vomiting and diarrhoea. We evaluated 123 pairs of questionnaires. Disagreement in grade of anorexia, vomiting and diarrhoea was found in 24, 7 and 13% of paired questionnaires, respectively (κ = 0.63, 0.83 and 0.71, respectively). Although 'good' to 'very good' agreement was found, the potential for only 'fair' agreement between questionnaire methods is of concern and suggests a need to adopt a standardized form. 相似文献
20.
The purpose of this study was to find out if an LMA (#1 LMA‐Classic) would provide a better airway than a face mask in spontaneously breathing anesthetized rabbits, and to test if it could be used for mechanically controlled ventilation. Sixteen rabbits (4.1 ± 0.8 kg, mean ± SD) were assigned randomly to three treatment groups; face mask with spontaneous ventilation (FM‐SV; n = 5), LMA with spontaneous ventilation (LMA‐SV; n = 5), and LMA with controlled ventilation (LMA‐CV; n = 6). Rabbits were anesthetized in dorsal recumbency using a circle circuit at constant ET isoflurane (2.3%, Datex airway gas monitor) and constant rectal temperature (38.85 °C) for 2 hours. PaCO2, PaO2, minute volume, tidal volume (Wright's respirometer), and Pe CO2 were measured at 15 minute intervals. Two individuals in the FM‐SV group had PaCO2 >100 mm Hg (>13.3 kPa). One rabbit in the FM‐SV had PaO2 <80 mm Hg (<10.7 kPa). All FM‐SV rabbits showed signs of airway obstruction and two were withdrawn from the study at 45 and 90 minutes, respectively, because of cyanosis. Tidal volume could not be measured in the FM‐SV group. No signs of airway obstructions were observed in either of the LMA groups. Four rabbits in the LMA‐CV group developed gastric tympany, and one of these refluxed after 110 minutes. The significance of differences between the two spontaneously breathing groups and between the two LMA groups were measured using Wilcoxon's rank sum test (with significance assumed at p < 0.05). There were no statistical differences between FM‐SV and LMA‐SV in any variable tested. PaCO2 and Pe ′CO2 were less in the LMA‐CV group than in the LMA‐SV group, while PaO2, tidal volume, and minute volume were all more. We conclude that biologically, the LMA provides a better airway than the face mask during spontaneous breathing and that it can be used for IPPV, but that gastric tympany is likely to occur during IPPV. 相似文献