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1.
The possibility of estrus prevention in the queen by the oral administration of chlormadinone acetate was examined. The animals used were 29 mature and 15 immature queens. For 16 mature females, 4-12.5 mg was given daily by mouth for 7 days every 3 months. Ten of the 16 queens given this treatment came into estrus within 4 months of the first treatment. For 28 females including the immature, 2-12.5 mg was given once a week throughout the experiment. This treatment prevented estrous activity for at least 1 year. In the queens in this study, the side effects were not observed excepting an increase in body weight during treatment. Our results showed that oral administration of this drug weekly is safe and reliable for long-range prevention of estrus in queens.  相似文献   
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Bovine granulosa cells (GC) vary in their morphological aspect during different stages of folliculogenesis. In this study, 10 morphologically normal bovine ovaries were collected to study the structural aspects of different stages of GC using intermediate filament protein antibodies including cytokeratin AE1/AE3 (AE1/AE3), vimentin, nectin‐4 and desmin. Hormonal immunolocalization was assessed using the immunomarkers anti‐Müllerian hormone (AMH) and inhibin alpha. In addition, tumour markers and proliferation markers using c‐erbB‐2 oncoprotein and proliferating cell nuclear antigen, respectively, were investigated. The immunolabelling of AE1/AE3 in GC was strongest in the early follicle stage and gradually decreased when reaching the Graafian follicle stage. Its immunolabelling increased again as the stage progressed from stage I to stage III. The immunolabelling of inhibin alpha was inversely proportional to that of AE1/AE3 in the developing ovarian follicles as their immunolabelling is opposite to each other during folliculogenesis. AMH was immunopositive in almost all GC stages in different intensities and percentages, except for some negative staining in the atretic IV follicles. The atretic IV follicle is a unique type of atretic follicle that shows Call‐Exner body formation, which was mainly found in older cows in this study. The distinct patterns of immunoreactivity for various types of immunomarkers in the different GC stages will play an important role in diagnostic assistance of various follicle conditions, including cystic ovaries and GC tumours.  相似文献   
4.
We have previously reported that the scallop shell extract possesses free radical scavenging activity. In this study, we isolated a glycoprotein with a molecular weight of approximately 90 kDa (named 90-kDa protein) which showed 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide anion radical scavenging, reducing, and ferrous ion-chelating activities. Amino acid composition analysis showed that the 90-kDa protein was rich in Asx (Asp or Asn), Ser and Gly residues. A BLAST search of partial amino acid sequences determined by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry revealed that the 90-kDa protein is a novel protein. The 90-kDa protein is a yellow protein that contains fluorescent substances. To the best of our knowledge, this is the first report of a radical scavenging protein from the scallop shell.  相似文献   
5.
In south‐western Japan, centipedegrass (Eremochloa ophiuroides; CG) offers a novel option for a warm‐season perennial for grazing use in areas where bahiagrass (Paspalum notatum; BG) can be grown. However, the potential of CG as a forage has not been fully explored because of the short history as a forage crop. We conducted four experiments to evaluate CG (cv. TifBlair) in comparison with BG (cv. Pensacola) in terms of sward characteristics, nutritive value and choice by animals. In each experiment, four Japanese Black cows (Bos taurus) were individually allowed to graze conterminous monocultures of CG and BG (5 × 10 m each) for 30 min. Irrespective of regrowth durations and fertilizer rates, CG was consistently shorter, leafier and denser, contained lower acid detergent fiber and cellulose, and was preferred or equally selected by cows, as compared with BG. Furthermore, CG maintained sufficient levels of crude protein (80–89 g/kg DM) to ensure voluntary intake of ruminant animals under extended regrowth? and without fertilizer, whereas BG failed to do so (65 g/kg DM). CG provided higher digestible dry matter than BG when crude protein concentration exceeded 86 g/kg DM. The results indicate advantages of CG as a forage.  相似文献   
6.
MX belongs to a family of type I interferon (IFN)-stimulated genes, and the MX protein has antiviral activity. MX has at least two isoforms, known as MX1 and MX2, in mammals. Moreover, bovine MX1 has been found to have alternative splice variants—namely, MX1-a and MX1B. In ruminants, IFN-τ—a type I IFN—is temporarily produced from the conceptus before implantation and induces MX expression in the endometrium. However, the expression dynamics of MX after implantation are not clear. In the present study, we investigated the expression of MX1-a, MX1B and MX2 in the endometrium and placenta before and after implantation along with the expression of IFN-α, type I receptors (IFNAR1 and IFNAR2) and interferon regulatory factors (IRF3 and IRF9). Pregnant uterine samples were divided into five groups according to pregnancy days 14–18, 25–40, 50–70, 80–100, and 130–150. Tissue samples were collected from the intercaruncular endometrium (IC), caruncular endometrium (C) and fetal placenta (P). Although all the MX expressions were significantly higher in the IC and C at days 14–18, presumably caused by embryo-secreted IFN-τ stimulation, their expressions were also detectable in the IC, C and P after implantation. Furthermore, IFN-α expression was significantly higher in the IC. RT-PCR indicated IFNAR1, IFNAR2, IRF3 and IRF9 mRNA in all the tissues during pregnancy. These results suggest that all the MX genes are affected by the type I IFN pathway during pregnancy and are involved in an immune response to protect the mother and fetus.  相似文献   
7.
One-day-old, 2-wk-old, and 4-wk-old call ducks (Anas platyrhyncha var. domestica) inoculated intravenously with the H5N1 highly pathogenic avian influenza virus A/chicken/Yamaguchi/7/2004 isolate (Ck/Yama/7/04) were examined clinically, pathologically, and virologically. Clinically, the birds exhibited mild-to-severe neurologic signs and corneal opacity. All birds in the 1-day-old group and one bird in the 4-wk-old group died within 4 days after the virus inoculation. Histologic changes were characterized by severe nonpurulent encephalitis and necrotic lesions of feather epithelium on day 3 postinoculation (PI) or later. Focal necrosis of myocardial cells, pancreatic acinar cells, skeletal myocytes, and corneal epithelial cells was observed. Viral antigens were detected in association with necrotic changes. Viruses were isolated from all examined organs including the skin with many feathers. Serum antibody against the virus was detected in all surviving birds on day 10 PI by hemagglutination-inhibition tests. These results suggest that Ck/Yama/7/04 has a pathogenicity that causes neurologic sign, nonpurulent encephalitis with mortality, and feather lesions for call ducks. Feather lesions with viral antigens and the virus isolation from the skin suggest that Ck/Yama/ 7/04 has a predilection for feathers in call ducks.  相似文献   
8.
The aims of this study were to develop a new real-time quantitative PCR (QPCR) assay based on IS900 for detection and quantification of Mycobacterium avium subsp. paratuberculosis (MAP) DNA in faeces, and to use this to detect infected sheep. Both the C and S strains of MAP were detected by the QPCR assay, and no cross reactions were detected with 51 other species of mycobacteria including 10 which contained IS900-like sequences. One copy of IS900 fragment cloned into plasmid pCR2.1 and 1 fg of MAP genomic DNA were consistently detected, while in spiked faecal samples the detection limit was 10 viable MAP per gram of ovine faeces. A total of 506 individual ovine faecal samples and 27 pooled ovine faecal samples with known culture results were tested. The QPCR assay detected 68 of 69 BACTEC culture positive individual faeces and there was a strong relation between time to detection in culture and DNA quantity measured by QPCR (r= -0.70). In pooled faecal samples, QPCR also agreed with culture (kappa=0.59). MAP DNA was detected from some culture negative faecal samples from sheep exposed to MAP, suggesting that the QPCR has very high analytical sensitivity for MAP in faecal samples and detects non-viable MAP in ovine faeces. None of the faecal samples from 176 sheep that were not exposed to MAP were positive in QPCR. This is the first report of a direct faecal QPCR assay that has similar sensitivity to a gold standard radiometric culture assay.  相似文献   
9.
A trial was conducted to determine the effect of ascorbyl‐2‐monophosphate Na/Ca (AMP‐Na/Ca) on blood chemistry and nonspecific immune response of red sea bream juveniles. Test diets with three levels of AsA (free, 107, and 325 mg/kg diet) were fed to juvenile red sea bream (36.0 ± 1.3 g) two times a day for 3 wk. There were no significant differences in hematocrit, glucose, and blood urea nitrogen. Total cholesterol and triglyceride in plasma of fish fed AsA‐free diet was significantly (P < 0.05) higher than that of fish fed two other diets. There were no significant differences in serum albumin, total bilirubin, and total serum protein. Glutamyl oxaloacetic transaminase in serum of fish fed diets containing 107 and 325 mg of AsA were significantly (P < 0.05) lower than that of fish fed AsA‐free diet. Serum lysozyme activity (LA) of fish fed diets containing 107 and 325 mg of AsA were significantly (P < 0.05) higher than that of fish fed AsA‐free diet. There was no significant difference in mucus LA. The results mentioned above demonstrated that AMP‐Na/Ca is a bioavailable AsA source for red sea bream juveniles. Supplement of more than 107 mg AsA/kg in diets improved blood chemistry and nonspecific immune function of red sea bream juveniles.  相似文献   
10.
Fecal DNA samples from the red-eared slider and Reeves’ pond turtle, suspected pests of lotus root paddies, were used to identify the plant species eaten by these turtles in order to develop a strategy for rural ecosystem conservation. The fecal samples were obtained from young and adult individuals (mostly female) of both species living in agricultural canals surrounding lotus root paddies in Tokushima Prefecture, Japan. The samples were screened for the presence or absence of DNA from nine plant species using PCR and plant species-specific primers for the rbcL gene of chloroplast DNA. In the red-eared slider, our analysis identified seven plant species in the fecal DNA samples of adults and three plant species in those of young individuals. In Reeves’ pond turtle, our analysis identified two plant species from adult fecal samples and one species from those of young individuals. Thus, adult red-eared sliders consume a greater range of plants than young red-eared sliders or Reeves’ pond turtles. Both turtle species, independently of age, consumed lotus plants and were likely to cause feeding damage to lotus roots. Considering the plant species detected in adult red-eared sliders and these plant habitats, we suggest that this adult turtle is likely to travel between the agricultural canals and the lotus root paddies. These findings will help the development of strategies for preventing damage to lotus roots by these turtles; furthermore, they indicate that fecal DNA analysis will be applicable to investigation of the feeding habits of other animal species.  相似文献   
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