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991.
De Las Heras M Ortín A Salvatori D Pérez de Villareal M Cousens C Miguel Ferrer L Miguel Cebrián L García de Jalón JA Gonzalez L Michael Sharp J 《Research in veterinary science》2005,79(3):201-264
Ovine pulmonary adenocarcinoma (OPA) is a naturally occurring contagious lung neoplasia caused by jaagsiekte sheep retrovirus (JSRV). Although no specific circulating antibodies against the virus can be detected in infected sheep, JSRV proviral DNA sequences can be found in peripheral blood leukocytes (PBLs) in clinically affected and in a proportion of in contact animals. In this study, existing hemi-nested PCR procedure is compared with a new one-step PCR technique that was developed to minimise potential DNA contamination and reduce sample and reagent handling. Different blood preparations were assessed and the best results were achieved on DNA prepared from buffy coat. The sensitivity of this PCR was lower in JSRV infected sheep without lesions of OPA than in clinically affected sheep, which indicate that this PCR may not be not fully appropriate for screening of individual sheep, but rather to provide results at flock level. This PCR is the only currently available blood test for detection of JSRV infected sheep and may be useful in epidemiological studies and in control programmes of OPA. 相似文献
992.
Rosypal AC Troy GC Duncan RB Zajac AM Lindsay DS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(6):802-809
Eight female beagles were infected with 1 x 10(7) (low dose, LD) or 2 x 10(8) (high dose, HD) promastigotes of a North American isolate of Leishmania infantum infantum (LIVT-1 strain) isolated from naturally infected Virginia Foxhounds. Two female beagles served as negative controls and 2 male beagles chronically infected (> 3 years) with Leishmania infantum chagasi were positive controls. Bone marrow (BM) and lymph node (LN) aspirates were collected every 6-8 weeks for cytologic evaluation, parasite culture, and polymerase chain reaction (PCR). Serum samples were collected monthly for determination of serologic responses by indirect fluorescent antibody test (IFAT) and diagnostic rK39 antigen. Cultures of BM and LN aspirates and cytology evaluation were consistently positive in positive control dogs during the course of study. Negative control dogs were negative on BM and LN cultures and on cytologic evaluation of aspirates. Amastigotes were present on cytological examination of BM aspirates in 2 experimentally infected dogs. Cultures of LN aspirates were positive on 22 samples, whereas BM cultures were positive on 12 samples for all dogs. IFA titers ranged from 0 to 1 :400 in experimentally infected dogs during the course of the study. Recombinant K39 immunoassay tests were consistently positive in positive control dogs and in the HD dogs by approximately 8 weeks after infection. BM PCR products were identified more consistently in the HD dogs compared with the LD dogs. Kappa statistics indicated PCR correlated better with cultures and cytology than did IFAT or the rK39 immunoassay results in the experimentally infected dogs. 相似文献
993.
Determination of the seleno-enzyme glutathione peroxidase (GSH-Px) in blood from Danish Landrace pigs was done using a quantitative, spectrophotometric method and a simple “spot test”. A close correlation between the net reaction rate measured spectrophotometrically (Δ A/min.) and time for defluores-cence (minutes) was obtained (r2 = 0.72—0.77, P < 0.0005). From these results the factors used for a conversion of defluorescence time to u/g hemoglobin were evaluated. The results further showed that the “spot test” can be used as a screening method for detection of subnormal GSH-Px levels in pigs.While red cell GSH-Px seems independent of the sex, an elevation of both plasma and red cell GSH-Px was found with increasing age of pigs. The normal range of red cell GSH-Px activity was wide, contrasting the small variations observed in the individual pig. Some evidence that porcine red cell GSH-Px is under genetical control was found and discussed in relation to the possible use of GSH-Px as an indicator of the pig''s selenium status. 相似文献
994.
Six Swedish Red and White dairy cows, producing 20-39 kg of 4% fat-corrected milk were given a ration balanced in energy and protein. They had access to feed from 05.15 to 09.00 and from 13.00 to 16.30 and were milked at 06.15 and 15.30. The milk was analysed for urea with a FIA technique.There was a significant diurnal variation in milk urea. The highest values were found 3–5 h after the beginning of the morning feeding and the lowest values (down to 60% of the max. values) during late night. Within 1 h after the start of the morning feeding the urea values had increased significantly, but they had decreased within the same time after the start of the afternoon feeding. Since there was a pronounced diurnal variation in the milk fat content, the urea concentration was also recalculated to concentration in the water phase of the milk. It was higher in that phase, but the pattern of the diurnal variation was not changed significantly. However, analyses on milk with a very high fat content may give misleading results.There were no important differences in the milk urea concentration of different udder quarters. When calculated as concentration in the water phase of the milk, no differences in urea concentration were found between the beginning and the end of milking. The analytical method had a good precision (coefficient of variation max. 3%). The milk urea concentration was not changed significantly after storage during 10 days at 4°C when no preservative was added; but after 17 days the milk had turned sour and the urea value had increased. When a preservative (bronopole) was added the urea concentration remained unchanged during 17 days. Deepfreezing did not influence the urea concentration. 相似文献
995.
996.
997.
Summary Ten cultivars contrasting in chip quality were grown in the field and in the glasshouse to evaluate three different methods
for chip quality assessment. Specific gravity was also measured. The glasshouse culture simulated growth of seedlings and
the field culture represented growth of advanced breeding lines. Differences between cultivars for chip quality and specific
gravity could be established in both environments. Although ranking of the cultivars in both environments was not identical,
both good and bad genotypes could be identified. It seems that mild selection for specific gravity and chip quality among
glasshouse-grown seedlings can be exercised. If tubers of glasshouse-grown plants are too small to slice chips, Reflocheck
Glucose test strips offer a satisfactory alternative to frying chips.
Crip in UK 相似文献
998.
L. O. Wosu 《Comparative immunology, microbiology and infectious diseases》1984,7(3-4):201-206
Standardised procedure for obtaining reproducible haemagglutination-inhibition results for FPV antibody which correlate with serum-neutralization titres was described. Optimal conditions were found to be Alsevers anticoagulant, PBS/0.05% BSA (pH 6.8) as buffer, especially washed round bottom microplates, determination of maximally sensitive porcine erythrocytes, use of reproducible erythrocyte concentrations, inactivation of serum samples at 56 degrees C for 30 min and serum treatment with koalin pH 9.0. The concentration of erythrocyte used for estimation of haemagglutination units in H1 test should not differ from that used as indicator in the test. Predilution of serum beyond 1:4 associated with false results. Reproducible method for removing natural agglutinins in serum by adsorption with erythrocytes was described. 相似文献
999.
1000.
The effect of a water-soluble fraction (WSF) of a non-pathogenic strain of Mycobacterium phlei was studied in bovine subclinical mastitis (SCM) by measuring the myeloperoxidase and acid phosphatase enzyme levels in the milk leukocytes. Forty-five cows were divided into three equal groups. Group I, consisting of 15 healthy cows, served as the control, whereas groups II and III each contained 15 cows with subclinical mastitis on the basis of a positive reaction in the California mastitis test (CMT). The cows in group II received 100 microg of WSF in 5 ml sterile phosphate-buffered saline, pH 7.4 (PBS) once only, while those in group III received 5 ml sterile PBS daily for 7 days, both treatments being given by the intramammary route. Observations were made up to 30 days after treatment (AT). The CMT of the healthy milk was negative (0), whereas it ranged between 1 and 2 points in SCM. The somatic cell count (SCC) increased significantly (p < 0.05) on day 3, then fell steeply from day 7 up to day 30 AT in the cows in group II. A steady decrease in the total bacterial count (TBC) was observed in the group treated with WSF but the bacterial counts remained high in the groups treated with PBS. The mean acid phosphatase level was enhanced by 119% on day 3 AT in group II but only by 18.7% in the cows in group III. The mean myeloperoxidase level was enhanced by 100% in the cows in group II but only by 18% in those in group III on day 3 AT. This significant reduction in the bacterial load in infected cows caused by intramammary infusion of WSF may be due to activation of the microbicidal activity of the neutrophils, but this requires confirmation. 相似文献