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121.
The aim of the present study was to evaluate the effect of high pre‐slaughter environmental temperature on meat (Longissimus lumborum muscle) quality traits of Italian autochthonous pigs Suino Nero Lucano (SNL). High pre‐slaughter environmental temperature influenced the meat quality of autochthonous pigs. In particular, the meat from SNL pigs exposed to heat stress (H) showed significantly lower pH values at 24 and 48 hr post mortem, haem iron content and redness (a*) value, and a significantly higher shear force, drip loss and lightness (L*) values, compared to meat from SNL pigs reared under comfortable environmental temperature (C). Moreover, H meat showed a significant reduction of vitamin A, vitamin E, creatine and carnosine content, compared to C meat. Despite this, no pale‐soft‐exudative pork was found in our study, and no significant difference was detected between two studied groups for intramuscular fat and protein content of meat. In addition, despite the meat from SNL pigs exposed to heat stress has suffered a qualitative decrease, it showed a good endogenous antioxidants content.  相似文献   
122.
A two-year-old male domestic shorthair cat was seen because of sudden onset of incoordination and tremors that had rapidly worsened over five days. Neurological examination revealed severe cerebellar ataxia, intention tremors and bilaterally decreased menace response. Blood work evaluation included a complete cell blood count (CBC), serum biochemistry profile, urinalysis, faecal flotation, cerebrospinal fluid (CSF) analysis and retroviral testing. Except for testing positive for feline immunodeficiency virus (FIV) antibodies, all other results were within the normal range. The patient was euthanased two days later because of progression of clinical signs, and a necropsy was performed. Histologically, lesions were limited to the cerebellum and consistent with cerebellar abiotrophy. No secondary diseases that could explain the rapid development of clinical signs were found. It was considered unlikely that cerebellar degeneration was related to FIV positivity, as virus invasion of the central nervous system (CNS) is mainly limited to the cerebral cortex. This case report is the first to describe late onset and rapid progression cerebellar abiotrophy in a cat.  相似文献   
123.
124.
Plectosphaerella cucumerina has been described recently as the causal agent of a leaf spot on wild rocket (Diplotaxis tenuifolia). Eight seed samples of wild rocket obtained from commercial seed lots used for sowing by farms severely affected by P. cucumerina, were assayed for the presence of the pathogen. Isolations were carried out on subsamples of seeds (400) unwashed or disinfected in 1% sodium hypochloride. The pathogenicity of the isolates of P. cucumerina obtained was tested in two trials carried out on wild rocket; four out of eight samples of rocket seeds were contaminated by P. cucumerina. Eleven isolates of P. cucumerina were obtained from 7,200 not disinfected seeds tested, while none was isolated from an equal number of disinfected seeds. All isolates were pathogenic on wild rocket. The results obtained indicate that rocket seeds are a potential source of inoculum for P. cucumerina. The possibility of isolating the pathogen from seeds, albeit from a low percentage of them, supports the hypothesis that the rapid spread of this new disease of rocket recently observed in Italy is due to the use of infected propagation material. Measures for prevention and control of the disease are discussed.  相似文献   
125.
The factors responsible for the clinical progress of visceral leishmaniasis (VL) in dogs have not been yet established. The starting hypothesis was the possibility of associating the changing level of a specific type of cytokines with the evolution of the infection towards infection-manifested disease or resistant behaviour. For this purpose the authors have established a connection between Leishmania load, cytokine mRNA accumulation, and the progression of the disease in naturally infected asymptomatic dogs. We made use of real-time (RT) PCR system to detect the expression of cytokine mRNA levels during all the phases of the infection. In particular, we measured the amount of parasites in samples such as blood, lymph nodes and skin, and the expression levels of IFN-gamma, IL-2, IL-4, IL-10, IL-12 and IL-18 cytokines in the blood. We employed different targeted real-time PCR assay on 40 naturally infected dogs, initially asymptomatic; 20 of these progressed to overt disease, and the 20 remaining dogs remained asymptomatic throughout the period of study (2 years). Two other groups included: 20 naturally infected dogs with clinical signs of VL, and 20 healthy dogs living in a non-endemic area. All these animals were employed as positive and negative controls, respectively. The overall results obtained demonstrate that the simultaneous evaluation of parasites and cytokine levels represents a reliable tool for predicting disease development, and thus for choosing the best treatment for the asymptomatic form of the disease.  相似文献   
126.
OBJECTIVE: To compare 4 assay procedures for prediction of passive transfer status in lambs. ANIMALS: Thirty-one 1-day-old Sardinian lambs. PROCEDURE: Serum IgG concentration was determined by use of single radial immunodiffusion. The following were determined: serum total protein concentration as measured by refractometry (ie, refractometry serum total protein concentration), serum total protein concentration as determined by the biuret method (ie, biuret method serum total protein concentration), serum gamma-globulin concentration as determined by serum protein electrophoresis, and serum gamma-glutamyltransferase (GGT) activity as measured by spectrophotometry. Accuracy of these assays for estimation of serum IgG concentration in 1-day-old lambs was established by use of linear regression analysis. RESULTS: Refractometry serum total protein concentration, biuret method serum total protein concentration, and serum gamma-globulin concentration were closely and linearly correlated with serum IgG concentration. The natural logarithm (ln) of serum GGT activity was closely and linearly correlated with serum IgG concentration (ln). Refractometry serum total protein concentration, biuret method serum total protein concentration, and gamma-globulin concentration accounted for approximately 85%, 91%, and 95% of the variation in serum IgG concentration, respectively. Serum GGT activity (ln) accounted for approximately 92% of the variation in serum IgG concentration (ln). CONCLUSIONS AND CLINICAL RELEVANCE: For prediction of passive transfer status in 1-day-old lambs, serum GGT activity or biuret method serum total protein concentration determination will allow for passive transfer monitoring program development. Immediate refractometry serum total protein concentration determination is beneficial in making timely management and treatment decisions. Serum gamma-globulin concentration determination can be used as a confirmatory test.  相似文献   
127.
OBJECTIVE: To evaluate the effect of passive transfer status, determined by measuring serum IgG concentration 24 hours after parturition, on preweaning growth performance in dairy lambs. DESIGN: Prospective observational study. ANIMALS: 20 healthy Sardinian dairy lambs. PROCEDURES: Serum IgG concentration was measured 24 hours after birth. Body weight was measured at birth and at the time of weaning 28 days (ie, 27 to 29 days) after birth. Mean daily gain from birth to day 28 and day 28 weight were used as measures of preweaning growth performance. Regression analysis was used to evaluate associations between serum IgG concentration 24 hours after birth and measures of preweaning growth performance. RESULTS: Mean +/- SD serum IgG concentration 24 hours after birth was 24.6 +/- 17.5 mg/mL. Mean body weights at birth and weaning were 2,696 +/- 937 g and 9,253 +/- 2,116 g, respectively, and mean daily gain was 234 +/- 63 g/d. No significant association was detected between serum IgG concentration 24 hours after birth and birth weight. However, serum IgG concentration 24 hours after birth was significantly associated with mean daily gain (R(2) = 0.25). Each 1 mg/mL increase in serum IgG concentration 24 hours after birth was associated with a 1.8 g/d increase in mean daily gain and a 60.8-g increase in day 28 weight. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that passive transfer status, determined as serum IgG concentration 24 hours after birth, was a significant source of variation in preweaning growth performance in dairy lambs.  相似文献   
128.
The vacuum distillation of bergamot peels furnishes a high-quality essential oil that is totally bergapten-free. This oil was compared with that produced by distillation of cold-pressed oils and those commercially available. The oil obtained by vacuum distillation of the bergamot vegetable matrix shows a composition quite similar to that of the cold-pressed oil. It also displays qualitative characteristics that are superior with respect to those normally observed for essential oils isolated by distillation of cold-pressed oils. Oils isolated by the method presented here can constitute ideal candidates in producing foods, for example, Earl Grey tea, and cosmetic preparations.  相似文献   
129.
Visceral leishmaniosis is a life-threatening disease of medical, social and economic importance in endemic areas. It is an opportunistic infection in immunocompromised patients, including human immunodeficiency virus-positive subjects. Dogs are the main reservoir of Leishmania infantum. The aim of this study was to evaluate the efficacy of miltefosine and allopurinol for the control of human leishmaniosis using the dog as a model. The study included 28 sick dogs treated with miltefosine (2 mg/kg/day PO) administered concurrently with allopurinol (10 mg/kg/day, PO) for 30 days, and then with allopurinol alone, at the same dosage, for 1 year. Eight dogs (four of which relapsed) received a second cycle of miltefosine within 6 months of the first cycle. Efficacy was measured by real-time polymerase chain reaction assay on whole blood samples and lymph node aspirates, collected at baseline and every 3 months for 12 months. Of the total number of animals (28), two showed renal insufficiency and died after the start of therapy with miltefosine. Two other dogs presented some side effects to treatment, such as nausea, vomiting and reduction in white and red blood cell counts, and these animals were excluded from the follow-up. The results showed that the first cycle of therapy with miltefosine and allopurinol induced a drastic and progressive reduction of L. infantum load in lymph node aspirates but the second cycle did not eliminate the parasite.  相似文献   
130.
Downy mildew of lettuce, caused by Bremia lactucae, is difficult to control in soilless systems by using conventional methods of disease management because few chemicals are registered, while resistant cultivars face the problem of resistance break down; therefore other methods for disease control need to be investigated. The effect of silicon salt as well as increased electrical conductivities against downy mildew was evaluated in four experiments carried out in hydroponically systems, using the cultivar of lettuce “Cobham Green”, known for its susceptibility to the pathogen. Silicon, as potassium silicate, was added at 100 mg l−1 of nutrient solution at three levels of electrical conductivity: 1.5–1.6 mS cm−1 (EC1), 3.0–3.5 mScm−1 (EC2, 0.70 g l−1 NaCl) and 4.0–4.5 mS cm−1 (EC3, 0.95 g l−1 NaCl) respectively. Lettuce plants, grown for 14–20 (trials 1 and 2) and 36–45 (trials 3 and 4) days in the different nutrient solutions tested, were inoculated with B. lactucae conidia with a maximum of two inoculations before final disease assessment carried out 14–21 days after the inoculation able to give symptoms. EC and potassium silicate significantly influenced downy mildew incidence and severity, while their interaction was not a significant factor. The addition to the standard nutrient solution (EC1) of potassium silicate resulted in a significant reduction of downy mildew severity in trials 1 and 2 where plants were artificially inoculated 15 and 20 days after transplanting. This efficacy was slight on plants grown for 36 and 45 days before inoculation in a soil drenched with EC1 amended with potassium silicate. EC2 gave a significantly similar downy mildew reduction than EC2 added with potassium silicate in trial 3. Plants grown for 36 and 45 days at the highest electrical conductivity (EC3) showed a significant reduction in severity of downy mildew compared with that observed at EC2 level. The best results, in terms of disease control, were given by the addition of potassium silicate to the EC3 solution. This combination also led to a significantly increased plant biomass. The possibility and benefits of applying potassium silicate and increased EC amendments in practice is discussed.  相似文献   
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