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61.
A serological survey on the occurrence of group-specific chlamydial antibodies in random sera of Finnish sheep, cattle and horses was performed. The whole material consisted of 1347 serum samples, including 432 ovine, 454 bovine and 461 equine sera. The sera were sent to the laboratory for various serological tests during 1968–1972. Of the ovine sera 9.5%, bovine 12.8 % and equine 7.1 % showed a titer ≥ 1:16 in the complement fixation test.No definite geographic differences could be found in the distribution of the herds which showed positive results. The ubiquity of chlamydial infections in domestic mammals and their role as a cause of clinical diseases is discussed.  相似文献   
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Bacteremia is an important cause of morbidity and mortality in humans. In this study, we focused on the development of an animal model of bacteremia induced by non-typhoidal Salmonella. New Zealand White rabbits were inoculated with a human isolate of non-typhoidal Salmonella strain CVD J73 via the intra-peritoneal route. Blood samples were collected at specific time points and at euthanasia from infected rabbits. Additionally, tissue samples from the heart, lungs, spleen, gastrointestinal tract, liver and kidneys were obtained at euthanasia. All experimentally infected rabbits displayed clinical signs of disease (fever, dehydration, weight loss and lethargy). Tissues collected at necropsy from the animals exhibited histopathological changes indicative of bacteremia. Non-typhoidal Salmonella bacteria were detected in the blood and tissue samples of infected rabbits by microbiological culture and real-time PCR assays. The development of this animal model of bacteremia could prove to be a useful tool for studying how non-typhoidal Salmonella infections disseminate and spread in humans.  相似文献   
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In a completely randomized block design experiment, 16 ruminally cannulated sheep (40 ± 2.1 kg)fed a 50% concentrate 50% forage diet (DM basis) were given intraruminal doses of powdered Yucca schidigera extract (YSE). Doses of 0 (control), 100, 200, or 300 mg kg-1 diet were given at 8 p.m. and 4 a.m. On 15, 16, and 17 d of the experimental period, ruminal contents were sampled 0, 2, 4, 6, and 8 h after dosing, and blood samples were collected at the end of the experiment (18th and 19th d). Acidity was not affected (P>0.05) by the addition of YSE. Compared with the control, ruminal propionate concentration was increased by 29.4 and 29.8% (P>0.05) and the acetic acid concentration was decreased by 15.1 and 19.8% (P>0.05) at 4 and 6 h after YSE (300 mg kg-1) dosing, respectively. Ruminal ammonia concentration in the first 2 h after feeding was higher (P<0.05) in the sheep that did not receive YSE (increased by 17.57 mg 100 mL-1) than in those that received 200 mg kg-1 (increased by 6.77 mg 100 mL-1) or 300 mg kg-1 (increased by 6.50 mg 100 mL-1) YSE. Protozoan populations in the rumen were lower (P < 0.05) in the animals that received 300 mg kg-1 of YSE compared with the control. All serum parameters of the four groups were in the normal range and were similar among the treatment groups (P>0.05), after being fed for 19 d with different doses of YSE. The effect of YSE on ruminal ammonia concentration likely resulted from a decreased concentration of protozoan populations and, presumably, from ammonia binding by YSE.  相似文献   
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三峡工程对库区人群健康的影响研究   总被引:4,自引:0,他引:4  
采用定性和定量相结合的方法,研究由三峡工程兴建及运行带来的自然和社会环境变化对人群健康造成的影响.结果显示三峡库区自然疫源性疾病及虫媒传染病的流行和公共卫生突发事件发生都对人群健康造成了严重威胁,三峡工程的兴建也通过社会环境因素作用对人群健康产生潜在影响,导致与心理健康、移民和人口流动有关的疾病,以及公共卫生突发事件的发生.  相似文献   
67.
Approximately 1.4 million Salmonella infections and 400 deaths occur annually in the United States. Approximately 6% of human Salmonella cases are thought to be associated with reptiles; Salmonella enterica subspecies IV is primarily reptile-associated. During 1-4 December, 2009, three isolates of Salmonella IV 6,7:z4,z24:- with indistinguishable pulsed-field gel electrophoresis (PFGE) patterns were identified through Minnesota Department of Health laboratory-based surveillance. None of the three patients associated with the isolates reported reptile contact; however, all had attended the same potluck dinner. Dinner attendees were asked questions regarding illness history, foods they prepared for and consumed at the event, and pet ownership. Cases were defined as illness in a person who had eaten potluck food and subsequently experienced fever and diarrhoea (three or more loose stools in 24 h) or laboratory-confirmed infection with Salmonella IV matching the outbreak PFGE subtype. Nineteen days after the event, environmental samples were collected from a food preparer's house where two pet bearded dragons were kept. Sixty-six of 73 potluck food consumers were interviewed; 19 cases were identified; 18 persons reported illness but did not meet the case definition. Median incubation period was 19 h (range: 3-26 h). Median duration of illness was 5 days (range: 1-11 days). Consumption of gravy, prepared by the bearded dragons' asymptomatic owner, was associated with illness (16/32 exposed versus 1/12 unexposed; risk ratio: 6.0; exact P = 0.02). Salmonella Labadi was recovered from 10 samples, including from one bearded dragon, the bathroom door knob and sink drain, and the kitchen sink drain. The outbreak PFGE subtype of Salmonella subspecies IV was isolated from vacuum-cleaner bag contents. This foodborne outbreak probably resulted from environmental contamination from bearded dragons. Reptiles pose a community threat when food for public consumption is prepared in households with reptiles.  相似文献   
68.
Middle and inner ear infections have been reported as a clinical entity in swine, other animal species and humans. In pigs, the anatomical-pathological and microbiological findings have been described. In this report, we describe radiographic findings in affected pigs. A total of 25 pigs with a head tilt and circling, as clinical signs of otitis media and interna, were examined. The majority were weaner-pigs with dyspnea or rhinitis. In radiographs, there was an increased opacity of the bulla tympanica, often accompanied by marginal destruction or thickening of the bulla wall. The radiographic findings confirmed the clinical diagnosis in each affected pig, but there were 5 false positive interpretations.  相似文献   
69.
The incidence of myocardial sarcocystis infection and of myocardial pathological changes was recorded in samples of 79 healthy cattle obtained from an abattoir. The incidence rate of thin-walled cysts of S. cruzi was 81.0 %, while mixed infection with thick-walled cysts of S. hominis and/or S. hirsuta was found in 5.0 %. Focal interstitial myocarditis was found in 31.6 % of the samples. The sarcocystis infection and the interstitial mononuclear cell infiltrates were positively associated (P < 0.05). Intimai proliferations of musculo-elastic or fibro-elastic tissues in the intramural coronary arteries were found in 75.0 % of the cattle older than 3% years of age, and in 45.7 % of the cattle less than 3½ years old. No association of the arterial lesions and the sarcocystis infection was demonstrated.  相似文献   
70.
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