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101.
Hiskett EK Suwitheechon OU Lindbloom-Hawley S Boyle DL Schermerhorn T 《Veterinary research communications》2009,33(3):227-240
In most mammals, glucokinase (GK) acts as a hepatic “glucose sensor” that permits hepatic metabolism to respond appropriately
to changes in plasma glucose concentrations. GK activity is potently regulated by the glucokinase regulatory protein (GKRP),
which is encoded by the GCKR gene. GKRP binds GK in the nucleus and inhibits its activity. GK becomes active when it is released from GKRP and translocates
to the cytosol. Low glucokinase (GK) activity is reported to be a principal feature of feline hepatic carbohydrate metabolism
but the molecular pathways that regulate GK activity are not known. This study examined the hypothesis that species-specific
differences in GKRP expression parallel the low GK activity observed in feline liver. Hepatic GKRP expression was examined
using RT-PCR, immunoblot, and confocal immunomicroscopy. The results show that the GCKR gene is present in the feline genome but GCKR mRNA and the GKRP protein were absent in feline liver. The lack of GKRP expression in feline liver indicates that the low
GK activity cannot be the result of GKRP-mediated inhibition of the GK enzyme. However, the absence of the permissive effects
of GCKR expression on GK expression and activity may contribute to reduced GK enzyme activity in feline liver. The study results
show that the cat is a natural model for GCKR knockout and may be useful to study regulation of GCKR expression and its role in hepatic glucose-sensing and carbohydrate metabolism. 相似文献
102.
Maddur MS Mohan MS Gajendragad MR Kishore S Gopalakrishna S Singh N 《Veterinary research communications》2009,33(2):103-109
Humoral and mucosal (secretory antibody)immune response to FMDV type Asia 1 in cattle was analyzed after vaccination and infection
using virus neutralizing test (VNT). Vaccination (1/16th the usual dose) failed to protect cattle from generalized clinical
disease following experimental FMDV Asia 1 infection. Our results showed that infection induced higher and prolonged serum
antibody titres indicating antigen mass is important for optimal immune response. Experimental FMDV infection induced significant
secretory antibody (mucosal) response in cattle. Though, there was no difference in the serum antibody response between the
cattle that developed generalized infection (unprotected) and those with only localized infection (protected), secretory antibody
response differed, wherein the unprotected cattle had higher secretory response than protected cattle. Thus, FMDV Asia 1 infection
stimulates a similar serum antibody response and a unique secretory antibody response among the infected cattle.
An erratum to this article can be found at 相似文献
103.
104.
Gerardo Ordaz-Ochoa Aureliano Juárez-Caratachea Rosa Elena Pérez-Sánchez Rafael María Román-Bravo Ruy Ortiz-Rodríguez 《Tropical animal health and production》2017,49(5):1025-1033
The effect of spineless cactus intake (Opuntia ficus-indica) on blood glucose (BG) levels in lactating sows and its impact on daily and total feed intake (dFI?1 and TFI, respectively), body weight loss (BWL), and weaning-estrus interval length (WEI) were evaluated. Thirty-four hybrid (Yorkshire × Landrace × Pietrain) sows in lactation phase were used. Sows were divided into two groups: G1 (n = 17) where they received commercial feed and G2 (n = 17) provided with commercial feed plus an average of 2.0 ± 0.5 kg spineless cactus, based on a sow’s body weight. The variables evaluated were BG, dFI?1, TFI, BWL, and WEI. Statistical analysis was performed by using a fixed and mixed model methodology, under a repeated measurements experiment. Group effects were found on all analyzed variables (P < 0.05). The BG was lower in G2 (55.2 and 64.5 mg/dL pre- and post-prandial, respectively), compared to that in G1 (70.9 and 80.1 mg/dL pre- and post-prandial, respectively) (P < 0.05). G2 showed better performance than G1 for dFI?1, BWL, and WEI (P < 0.05) whose averages were 5.5 ± 1.8 kg, 7.4 ± 4.5%, and 5.3 ± 1.2 days, respectively. Averages for these variables in G1 were 4.7 ± 1.5 kg, 16.8 ± 4.6%, and 6.1 ± 1.6 days, respectively. Intake of spineless cactus reduced BG levels in lactating sows, generating greater dFI?1, lower BWL at the end of lactation, and a lower WEI. 相似文献
105.
B Guo Z Tian B-C Han X-M Zhang Z-M Yang Z-P Yue 《Reproduction in domestic animals》2009,44(4):638-642
Hoxa10, a homeobox gene, is necessary for endometrial receptivity to blastocyst implantation. The aim of this study was to investigate the differential expression of Hoxa10 in canine uterus during early pregnancy and its regulation under different conditions by in situ hybridization. Hoxa10 mRNA was mainly localized in glandular epithelium and myometrium in canine uterus. There was a low level of Hoxa10 expression in the glandular epithelium on days 6, 12 and 17 of pregnancy. On day 20 of pregnancy when embryo implanted, Hoxa10 mRNA was highly expressed in the glandular epithelium surrounding the embryo, but not in the luminal epithelium. The expression of Hoxa10 mRNA gradually declined from day 23 and reached a low level on day 28. In the myometrium, a low level of Hoxa10 mRNA signal was seen on days 6, 12 and 17 of pregnancy and reached a high level on day 20 of pregnancy. During the estrous cycle, a high level of Hoxa10 mRNA expression was seen in the estrous uterus. Either estrogen or progesterone significantly induced the expression of Hoxa10 mRNA in the ovariectomized canine uterus. These results suggest that Hoxa10 expression is closely related to canine embryo implantation and upregulated by estrogen and progesterone. 相似文献
106.
107.
Xin-Yan Han Qi-Chun Huang Wei-Fen Li Jun-Fang Jiang Zi-Rong Xu 《Livestock Science》2008,119(1-3):216-220
The objective of this study was to investigate toxic effects of aflatoxin B1(AFB1) on growth performance, organs, hepatic enzyme activities, apparent digestibility of nutrients and digestive enzyme activities in ducks. Ninety 1-day-old Cherry Valley commercial ducks were designed to three treatment groups with three replicates of ten birds each. Group I (control) was fed conventional feed free of AFB1, group II or III was fed the diets containing 20 μg/kg or 40 μg/kg AFB1-contaminated rice respectively. The feeding trial lasted 6 weeks. The results were that decreased body weight gain and feed intake, increased feed to gain ratio and selected organ weights (liver, kidney and pancreas) were observed in AFB1-treated groups. The activities of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were significantly increased in AFB1-contamined groups. The apparent digestibility of crude protein (CP) was significantly lower while activities of digestive enzyme from duodenum contents including protease, chymotrypsin, trypsin and amylase were increased in AFB1-treated group. These results indicated that AFB1 of feed could decrease growth performance and apparent digestibility of nutrients, change digestive enzyme activities of duodenum contents in duck. 相似文献
108.
Shi LH Ai JS Ouyang YC Huang JC Lei ZL Wang Q Yin S Han ZM Sun QY Chen DY 《Journal of animal science》2008,86(5):1106-1113
To investigate the influence of histone deacetylases on nuclear reprogramming after nuclear transfer, we treated the cloned embryos with a histone deacetylase inhibitor, Trichostatin A (TSA). In the present study, global changes in acetylation of histone H3-lysine 14, histone H4-lysine 12, and histone H4-lysine 5 were studied in rabbit in vivo fertilized embryos, somatic cell nuclear transfer (SCNT) embryos, and TSA-treated SCNT embryos. From the pronuclear to the morula stage, the deacetylation-reacetylation changes in acetylation of histone H3-lysine 14 and histone H4-lysine 12 occurred in both fertilized embryos and TSA-treated cloned embryos; however, the distribution pattern in untreated cloned embryos failed to display such changes. More interesting, the signal of acetylation of histone H4-lysine 12 in cloned embryos was detected in both the inner cell mass and the trophectoderm, whereas TSA-treated cloned embryos showed the same staining pattern as fertilized embryos and the staining was limited to the inner cell mass. The histone acetylation pattern of TSA-treated SCNT embryos appeared to be more similar to that of normal embryos, indicating that TSA could improve nuclear reprogramming after nuclear transfer. 相似文献
109.
Eighteen multiparous Zebu cows in their third lactation and their calves were randomly allocated to three suckling periods, up to 3, 4 or 5 months of age of the calf. The cows were individually fed natural hay, cottonseed cake and molasses. At 2 months of age, all calves were separated from their mothers, and were offered cottonseed cake mixed with molasses and Mucuna hay individually. The calves stimulated milk ejection by suckling 30 seconds and suckled the residual milk for 45 minutes after milking. The dry matter intake of cows (3.68, 3.29 and 3.31% of body weight) and calves (2.88, 2.80 and 2.55% of body weight) for suckling up 3, 4 and 5 months of age, respectively, was not significantly affected by treatment and neither was the growth rate of the calves (178, 157 and 149 g/d for 3, 4 or 5 months suckling period, respectively). Cows suckling their calves up to 5 months had significantly higher milk yield and higher amount of saleable milk (1.97, 2.93 and 3.69 kg/cow/d for 3, 4 and 5 months suckling period, respectively). The fat content of the milk decreased with increasing length of the suckling period while the protein content was not affected. In conclusion, a suckling period of 5 months resulted in higher total milk production and higher amount of saleable milk but did not seem to have any effect on calf growth when the calves were supplemented. 相似文献
110.