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191.
An African Swine Fever virus (ASFV) isolated in an 1983 outbreak of the disease in Piemonte, Italy, was related by restriction endonuclease analysis of the viral genome to ASFV strains isolated in the Dominican Republic (1978), Haiti (1981) and Cameroon (1982).  相似文献   
192.
A monoclonal antibody was used to characterize a serogroup 1 specific Legionella pneumophila Philadelphia strain 1 antigenic determinant. A quantitative fluorometric assay was developed to quantitate the antibody sites (2.7 +/- 0.4 X 10(5)) on Legionella bacteria and to determine the physico-chemical parameters of the antibody-antigen interaction (at 4 degrees C: delta G = -10.9 Kcal X mol-1, delta H = 1.7 Kcal X mol-1, delta S = 45 cal X K-1 X mol-1). The same method was used to study the modification or the removal of the antigen by chemical and enzymatic means (trypsin, papain, lysozyme, acetone, chloroform-methanol and Tris-EDTA); only Tris-EDTA extraction resulted in a significant decrease in antibody binding sites. Inhibition studies of the fluorescein-labelled antibody binding were performed with different sugars of which only L-fucosylamine was inhibitory, and with other monoclonal antibodies to Legionella pneumophila serogroup 1 in order to compare their fine specificity and affinity. The results indicate that the epitope recognized was an immunodominant carbohydrate including an aminodideoxyhexose and carried by the lipopolysaccharide.  相似文献   
193.
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   
194.
The reference strains of the 12 serotypes of Actinobacillus pleuropneumoniae express one or two of three different RTX exotoxins designated Apx I, Apx II and Apx III. The toxins are important virulence factors. In the present study, ELISAs with purified Apx I, Apx II and Apx III, respectively, as antigen were evaluated as candidates for serological diagnosis of Actinobacillus pleuropneumoniae infection in pigs. The pigs were inoculated with biotype 1, serotypes 1-12, and biotype 2, serotype 14, respectively. A strong humoral antibody response was seen to all the three antigens in most pigs irrespective of the serotype used for inoculation. However, titers to the exotoxins secreted by the serotype used for inoculation were generally highest. The results show that toxin proteins of Actinobacillus pleuropneumoniae are antigenically related and that a correlation between serotype and secretion of exotoxin is not revealed serologically in the ELISA test.  相似文献   
195.
Preputial tumours in ferrets are frequently malignant and therefore warrant prompt investigation. As many cases do not respond favourably to surgery, even in combination with radiation therapy, wide surgical resection has been recommended. Such a procedure may necessitate partial or total penile resection but outcomes have thus far not been well described. The current case series describes two ferrets in which surgical resection, including penile amputation, was performed using 10 and 5 mm margins, respectively. In the first case, no recurrence of preputial gland adenocarcinoma was noted for 32 months postsurgery, whereas multiple attempts at surgery and radiation therapy were unsuccessful in the second. These cases suggest that margins of at least 1 cm may help achieve a better outcome. Penile amputation for the treatment of preputial tumours appears to be well tolerated by ferrets, as demonstrated by these cases.  相似文献   
196.
The outermost layer of skin, the epidermis, is cornified epithelial tissue composed of keratinocytes. To maintain the structure and function of the epidermis, the regulation of proliferation, differentiation, and cornification of keratinocytes is crucial, and various soluble factors secreted by keratinocytes are involved in these regulations. Previously, work has shown that keratinocytes secreted the protein Kdap (keratinocyte differentiation-associated protein) associated with the formation of cornified cell envelopes, a specialized protective barrier structure on the periphery of terminally differentiating keratinocytes. In the present report, the canine counterpart of human Kdap is identified and an attempt has been made to define its physiological role in canine keratinization. Canine Kdap (cKdap) showed structural features commonly observed in other counterparts and is secreted from transfected cells. The expression profile of cKdap mRNA, which was restrictively expressed in cornified epithelial tissues besides skin has also been determined. These findings indicate that there is a strong association between cKdap expression and cornification, which supports previous observations that Kdap is involved in the synthesis and/or degradation of cornified cell envelopes in humans and mice.  相似文献   
197.
This study describes longitudinal changes in serum levels of biochemical markers of bone cell activity in a group of 24 thoroughbred foals from birth to 18 months of age. The markers of bone formation included the type I collagen carboxy-terminal propeptide (PICP), the bone-specific isoenzyme of alkaline phosphatase (BAP), and osteocalcin (OC). Levels of the cross-linked telopeptide of type I collagen (ICTP), a marker of bone resorption, and the N-terminal propeptide of type III collagen (PNIIIP), a marker of soft tissue turnover, were also measured. Levels of all markers fell significantly between birth and 18 months of age (70-80 per cent); this decrease being most marked between 0 and 6 months. However, a transient increase in levels of the markers then occurred between 6 and 14 months of age. The timing of this increase was specific for each parameter. ICTP and OC concentrations increased between October and December. PICP concentrations increased between December and April whereas the increase in PIIINP was coincident with the peak in weight gain between April and June. Changes in BAP concentration were less distinct at this time. Season was shown to have significant effects on the biochemical markers independent from the effect of age. Concentrations of all markers decreased with increasing body weight and at any given age heavier horses had lower marker levels. These results show that biochemical markers of bone cell activity and soft tissue turnover follow characteristic patterns of change in growing thoroughbreds influenced by age, season and bodyweight. The demonstration that the reference ranges for the biochemical markers change from month to month means that single samples from individuals are of little value for monitoring bone cell activity in growing thoroughbreds.  相似文献   
198.
The prevalences of Cryptosporidium parvum, rotavirus, bovine coronavirus (bcv), and enterotoxigenic Escherichia coli (E coli k99) were determined in diarrhoeic dairy calves aged one to 21 days on 71 dairy farms in western Switzerland during the winter of 2005 to 2006. Faecal samples from 147 untreated calves suffering from acute diarrhoea were analysed by standardised diagnostic methods, and the immunoglobulin status of each calf was evaluated. The prevalences of C parvum, rotavirus, bcv and E coli k99 were 55.0 per cent, 58.7 per cent, 7.8 per cent and 5.5 per cent, respectively. The proportions of herds positive for the respective pathogens among the herds with diarrhoeic calves were 41.7 per cent, 52.1 per cent, 2.1 per cent and 2.1 per cent. The immunoglobulin concentration in the serum of 90.5 per cent of the diarrhoeic calves was below 8 g/l.  相似文献   
199.
200.
The use of feathers as noninvasive physiological measurements of biomarkers in poultry research is expanding. Feather molting patterns and growth rates, however, are not well described in domestic poultry. These parameters could influence the measurement of these biomarkers. Therefore, the objective of this study was to describe the juvenile primary feather molting patterns and feather growth rates for domestic turkeys. The 10 primary wing feathers of 48 female turkeys were measured weekly from week 1 (0 d of age) to week 20. Feathers were manually measured, and the presence or absence of each primary feather was recorded weekly. Generalized linear mixed models were used to investigate if feather growth differed between the primary feathers. The molting of the juvenile primary feathers followed a typical descending pattern starting with P1 (5 wk of age), while P9 and P10 had not molted by the end of the study (20 wk of age). The average feather growth rate was 2.4 cm/wk, although there was a significant difference between the 10 primary feathers (P < 0.0001, 2.1 to 2.8 cm/wk). Over time, feather growth followed a pattern where the growth rate reaches a peak and then declines until the feather is molted. The results of this study provide a critical update of patterns of molting and feather growth in primary wing feathers of modern turkeys. This can have implications for the interpretation of physiological biomarkers, such as the longitudinal deposition of corticosterone, in the feathers of domestic turkeys.  相似文献   
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