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71.
This case report describes the findings in a seven-month-old heifer with diabetes insipidus attributable to internal hydrocephalus. The heifer was referred to the clinic because of reduced appetite, polydipsia, decreased faecal output and weight loss. The heifer was examined daily for 8 days. She was thin and weak and had a dull dry hair coat and decreased appetite. The heifer urinated frequently; the urine was clear and yel low, had a specific gravity of 1.015. A complete blood cell count, biochemical profile and blood gas analysis revealed increased serum urea, increased serum creatinine, hypernatraemia, hyperchloraemia, hypercalcaemia and hypophosphataemia. The heifer received 10 litres of water and 3 litres of ruminal fluid from a healthy cow per os daily for 5 days. The heifer had access to fresh water ad libitum. The general condition of the heifer did not improve after this treatment. Although the concentration of serum urea and creatinine decreased, the concentrations of sodium, chloride and calcium remained higher than normal. Based on the findings, a diagnosis of diabetes insipidus was made and the heifer was euthanatized. Postmortem examination revealed severe internal hydrocephalus, and a definitive diagnosis of central diabetes insipidus attributable to internal hydrocephalus was made.  相似文献   
72.
This case report describes the findings in a 10-year-old goat with metastasis of an adenocarcinoma in the iris. Two weeks before admission, the owner had noticed blepharospasm of the left eye. Clinical examination by the referring veterinarian revealed unilateral intraocular hemorrhage. The goat was referred to our clinic for further work-up. The rectal temperature was 40 degrees C. The most important haematological result was severe thrombocytopenia. There was mild corneal oedema of the left eye. Approximately 75 per cent of the anterior chamber was filled with non-coagulated blood. The fluid in the anterior chamber dorsal to the blood was cloudy, and the corpora nigra could not be seen clearly. All other internal parts of the eye could not be seen. Ultrasonography of the left eye confirmed cloudiness of the anterior chamber and revealed moderate thickening of the iris. The right prescapular lymph node was markedly enlarged. Cytological examination of a fine needle aspirate of the lymph node showed a mixed population of neoplastic cells. Based on immunohistochemical evaluation of the cells metastasis of a carcinoma was diagnosed. The goat was subjected to euthanasia, and a postmortem examination was carried out. The anterior chamber of the left eye contained blood, and the iris was thicker than normal and adhered to the posterior surface of the cornea. There were neoplastic alterations in the iris, the oesophagus, the lung lobes, the liver, the kidney and in the prescapular, retropharyngeal, mediastinal and hepatic lymph nodes. Histologically, a diagnosis of carcinoma was confirmed, but the origin of the tumour could not be determined.  相似文献   
73.
The clinical findings and treatment of 3 calves with bleeding attributable to severe thrombocytopenia (1000 to 5000 platelets/microl) are described. The calves responded to treatment with whole blood transfusion, dexamethasone and other drugs. One calf was subsequently diagnosed with persistent bovine viral diarrhoea virus infection and was euthanased despite a favourable response to treatment. The other two calves were discharged after platelet counts had normalised and bleeding had stopped.  相似文献   
74.
BACKGROUND: Urea and creatinine are the most frequently used indirect markers in plasma and serum of glomerular filtration rate in dogs. Both have been shown to lack sensitivity but their diagnostic efficiency for the diagnosis of kidney disease has been minimally investigated. OBJECTIVE: The purpose of this retrospective study was to investigate the influence of possible factors of variation on both analytes and to determine whether specific decision rules should be drawn up for subpopulations of dogs. METHODS: The results of urea and creatinine measurements, breed, sex, age, and health status (healthy, renal disease, or nonrenal disease) of 3822 dogs were collected from the archives of 5 veterinary clinics. Data were analyzed with univariate and multivariate decision rules with and without adjustment. RESULTS: There were significant effects and interactions of almost all of the sources of variation. Slight improvements in diagnostic efficiency were obtained by adjusting the decision rules to these sources of variations. Univariate decision rules gave approximately the same diagnostic efficiency for urea and creatinine concentrations, with sensitivity and specificity in the range of 70% and 90%, respectively, using the upper limit of the reference interval as the threshold value. Multivariate decision rules provided only minor improvements in diagnostic efficiency. CONCLUSION: Simultaneous measurement of both urea and creatinine is of limited diagnostic value over the analysis of a single variable. Creatinine is the preferred analyte as it is affected by fewer extrarenal factors of variation.  相似文献   
75.
Mammary glands taken at slaughter from healthy lactating cows were perfused in vitro with warmed and gassed Tyrode solution. Marbofloxacin was administered "systemically" via the perfusion fluid at concentrations similar to those measured in plasma following intravenous administration of 2mg/kg marbofloxacin. Samples from the perfusate were taken over a 24h period. Glandular tissue samples at different vertical distances from the teat up to the udder base were gathered from each of the four quarters after 3, 6, 12 and 24h. The marbofloxacin content of the tissue samples was analysed by high performance liquid chromatography with UV detection. The addition of marbofloxacin to the perfusion fluid produced median concentrations above the MIC90 (0.016microg/mL) against Escherichia coli at all glandular tissue sites measured after 3 and 6h with remarkable variations. Samples taken after 12 and 24h contained marbofloxacin in concentrations (median) of 0.22 (<0.05-0.32)microg/g and 0.13 (<0.05-0.16)microg/g. It is concluded that a systemic administration of marbofloxacin is well suited for the treatment of E. coli mastitis.  相似文献   
76.
77.
ObjectiveTo determine the effects of propofol or thiopental induction on intraocular pressures (IOP) in normal dogs.Study designProspective randomized experimental study.AnimalsTwenty-two random-source dogs weighing 19.5 ± 5.3 kg.MethodsDogs were randomly assigned to receive propofol 8 mg kg−1 IV (group P) or thiopental 18 mg kg−1 IV (group T) until loss of jaw tone. Direct arterial blood pressure, arterial blood gasses, and IOP were measured at baseline, after pre-oxygenation but before induction, before endotracheal intubation, and after intubation.ResultsThere were no significant differences between groups with regard to weight, body condition score, breed group, or baseline or before-induction IOP, arterial blood pressure, or blood gases. The baseline IOP was 12.9 mmHg. Before endotracheal intubation, IOP was significantly higher compared to baseline and before induction in dogs receiving propofol. After intubation with propofol, IOP was significantly higher compared to thiopental and was significantly higher compared to before induction. After intubation, IOP was significantly lower compared to before intubation in dogs receiving thiopental. Propofol increased IOP before intubation by 26% over the before-induction score and thiopental increased IOP by 6% at the same interval. The IOP in group P remained 24% over the before induction score whereas thiopental ultimately decreased IOP 9% below baseline after intubation. There was no significant relationship between any cardiovascular or blood gas parameter and IOP at any time. There was no significant relationship between the changes in any cardiovascular or blood gas parameter and the changes in IOP between time points.Conclusions and clinical relevancePropofol caused a significant increase in IOP compared to baseline and thiopental. Thiopental caused an insignificant increase in IOP which decreased after intubation. Propofol should be avoided when possible in induction of anesthesia in animals where a moderate increase in IOP could be harmful.  相似文献   
78.
ABSTRACT Monoconidial isolates of Venturia inaequalis were collected in 1990 and 1991 from orchards in New York, Michigan, and Nova Scotia that had never or only sporadically been treated with fungicides acting as sterol demethylation inhibitors (DMIs). Sensitivities of isolates to two representative DMIs (fenarimol and myclobutanil) were determined by a sensitivity test based on the relative growth (RG) of mycelial colonies at one discriminatory dose. Mean isolate sensitivities were not significantly different (P > 0.2) for the majority of the populations tested, and all sensitivity data obtained from these sites were combined to provide a baseline distribution of isolate sensitivities for both fenarimol and myclobutanil. The baseline distributions were compared with isolate sensitivities determined for an experimental orchard in Nova Scotia with a documented case of DMI resistance and for a commercial orchard in Michigan with a long history of DMI use and first evidence of practical DMI resistance. For both DMIs tested and in both treated orchards, frequencies of isolates with RG values <80 had decreased or only slightly increased compared to the baseline population. In contrast, frequencies of isolates with RG values >80 had increased more than 20-fold over baseline levels. Thus, isolates with RG values >80 were rated DMI resistant. The validity of a qualitative isolate classification was tested in controlled infection studies. At doses of fenarimol and myclobutanil recommended for commercial control of apple scab, reproduction of a typical sensitive isolate on treated apple leaves was suppressed completely. Lesions caused by a resistant isolate continued to expand and produced abundant conidia. Statistical analysis of orchard sensitivities revealed that the analysis of isolate counts grouped into the categories DMI sensitive or resistant was most indicative in comparisons of orchard sensitivities aimed at detection of practical DMI resistance. A high degree of cross-resistance between fenarimol and myclobutanil indicated that sensitivity tests with one of the DMIs employed as the diagnostic tool in this study can serve as a test for other DMIs.  相似文献   
79.
80.
Genetic diversity for micronutrient efficiency among the most highly adapted and advanced hexaploid and tetraploid wheat cultivars in the world is limited compared with alien species of wheat or rye. Therefore, screening for zinc efficiency was conducted in greenhouse experiments under controlled conditions, and in field trials. Different varieties of hexaploid wheat, hexaploid oats and diploid rye, together with hexaploid and octoploid triticales, wheat-Agropyron, wheat-Aegilops and several wheat-alien chromosome addition series were studied. Considerable differences in zinc efficiency were found between wheat and its relatives. Individual chromosomes of Secale, Agropyron and Haynaldia were found to carry major genes for this character. The transfer of alien chromosome segments was effective, demonstrated using several wheat-rye translocation lines. Alien genetic information was clearly expressed in the wheat genetic background. Further experimental introgressions by chromosome manipulation and marker-aided selection may efficiently contribute to wheat improvement in marginal soils. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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