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981.
为了研究virR和mprF基因在单核细胞增生性李斯特氏菌中的分布状况,为单核细胞增生性李斯特氏菌的防治及追踪污染源提供依据,本试验以分离自石家庄、保定地区的生鲜肉、水产品、速冻食品等6类不同来源共189株单核细胞增生性李斯特氏菌菌株为研究对象,利用热启动PCR技术对virR和mprF基因的分布进行了检测。结果表明:virR基因的总检出率为92.1%,mprF基因的总检出率为96.3%,且同时含有这2个基因的概率为91.5%;食品来源不同,单核细胞增生性李斯特氏菌virR、mprF基因的检出率稍有差异,且同一来源的菌株其mprF的检出率都稍高于virR,这表明不同的基因在单核细胞增生性李斯特氏菌中的分布存在差异。  相似文献   
982.
From the statistical data is not difficult to find, the growth of construction industry has been falling, construction industry of the labor productivity and the rate of technical equipment is slow-moving. It shows that the Construction Industry is still in Ruggedly management mode in many areas, lacking of technological innovation. Therefore, the paper evaluate the technology innovation ability in construction industry in 31 provinces and cites of China using factor analysis, get the current status and find the difference, to find solutions for promote the technology innovation ability in construction industry.  相似文献   
983.
为探讨大规模、突击性抢建公共租赁住房面临的风险,在文献研究和实际调研的基础上,利用PSD技术平台进行风险诊断,采用头脑风暴法、德尔菲法进行风险识别,层次分析法(AHP法)评估各个风险因子对公共租赁房系统风险的贡献值,研究表明:①准则层中对公共租赁房系统风险中资金风险、规划选址风险、土地供给风险、建设管理风险的贡献值分别为0.460 1,0.287 5,0.185 3,0.067 1;②确保建设资金可持续性、完善选址区域基础设施是公共租赁住房制度持续健康发展的核心与关键.  相似文献   
984.
Risk factors associated with high or low long-term incidence of displaced abomasum (DA) or clinical ketosis were studied in 60 Swedish dairy herds, using multivariable logistic regression modelling. Forty high-incidence herds were included as cases and 20 low-incidence herds as controls. Incidence rates were calculated based on veterinary records of clinical diagnoses. During the 3-year period preceding the herd classification, herds with a high incidence had a disease incidence of DA or clinical ketosis above the 3rd quartile in a national database for disease recordings. Control herds had no cows with DA or clinical ketosis. All herds were visited during the housing period and herdsmen were interviewed about management routines, housing, feeding, milk yield, and herd health. Target groups were heifers in late gestation, dry cows, and cows in early lactation. Univariable logistic regression was used to screen for factors associated with being a high-incidence herd. A multivariable logistic regression model was built using stepwise regression. A higher maximum daily milk yield in multiparous cows and a large herd size (p = 0.054 and p = 0.066, respectively) tended to be associated with being a high-incidence herd. Not cleaning the heifer feeding platform daily increased the odds of having a high-incidence herd twelvefold (p < 0.01). Keeping cows in only one group in the dry period increased the odds of having a high incidence herd eightfold (p = 0.03). Herd size was confounded with housing system. Housing system was therefore added to the final logistic regression model. In conclusion, a large herd size, a high maximum daily milk yield, keeping dry cows in one group, and not cleaning the feeding platform daily appear to be important risk factors for a high incidence of DA or clinical ketosis in Swedish dairy herds. These results confirm the importance of housing, management and feeding in the prevention of metabolic disorders in dairy cows around parturition and in early lactation.  相似文献   
985.
986.
AIM:To study the effects of Zuogui pill(ZG)-medicated serum on the proliferation and differentiation of MC3T3-E1 cells via ERK/TGF-β/Smads signaling pathway. METHODS:Using Premarin(conjugated estrogens tablets) as a positive control, the SD female rats were fed with high-, medium- or low-dose of ZG suspension. ZG-medicated serum was separated from abdominal aortic blood 7 d after feeding of ZG. MTT assay was applied to test the effect of ZG-medicated serum on the viability of MC3T3-E1 cells. The production of alkaline phosphatase(ALP) was detected by a modified calcium and cobalt dyeing method. The calcified nodules were observed by the method of alizarin red staining. The levels of core binding factor α1(Cbfα1) and collagen type I(Col I) protein were analyzed by Western blotting. The mRNA expression of TGF-β1, Smad4 and Smad2 was measured by real-time RT-PCR. RESULTS:ZG-medicated serum promoted the proliferation of MC3T3-E1 cells in a dose-and time-dependent manner. Compared with other groups, treatment with 15% ZG(low dose) for 48 h increased the proliferation of MC3T3-E1 cells significantly. The protein levels of ALP, Cbfα1 and Col I,the calcified nodules, and the mRNA expression of TGF-β1, Smad4 and Smad2 in MC3T3-E1 cells were all significantly increased after treatment with ZG-medicated serum. After the addition of PD98059(a specific blocker of ERK1/2 signaling pathway), all those were down-regulated except for mRNA expression of TGF-β1. CONCLUSION:ZG regulates MC3T3-E1 cell proliferation and differentiation via the intervention of ERK/TGF-β/Smads signaling cascade, which may be one of the mechanisms that ZG effectively prevents and treats osteoporosis.  相似文献   
987.
AIM: To investigate the role of dual-specificity tyrosine phosporylation-regulated kinase 1A (Dyrk1A)-alternative splicing factor (ASF)-calcium/calmodulin-dependent protein kinase Ⅱδ (CaMK Ⅱδ) pathway in the progression of myocardial hypertrophy in renovascular hypertensive rats. METHODS: The renovascular hypertension was induced by two-kidney one-clip (2K1C) method. The changes of blood pressure and myocardial hypertrophy were measured. The techniques of RT-PCR and Western blotting were used to detect CaMKⅡδ alternative splicing and the protein expression of Dyrk1A and ASF, respectively. RESULTS: Eight weeks after operation, systolic blood pressure (SBP) and diastolic blood pressure (DBP) in 2K1C rats increased (P<0.05). The increases in left ventricular weight (LVW), the ratio of LVW to body weight (BW) and the area of myocardial cells indicated that the hypertensive rats developed significant cardiac hypertrophy. The protein expression of Dyrk1A and mRNA expression of CaMKⅡδA and δB were significantly increased, while the protein expression of ASF and mRNA expression of CaMKⅡδC were decreased compared with sham-operated control rats (P<0.05). Treatment with Dryk1A inhibitor epigallocatechin gallate (EGCG) or harmine effectively attenuated cardiac hypertrophy and reversed the changes in the protein expression of Dyrk1A, ASF and alternative splicing of CaMKⅡδ (all P<0.05). CONCLUSION: Dyrk1A-ASF-CaMKⅡδ pathway plays a role in the development of myocardial hypertrophy in renovascular hypertensive rats.  相似文献   
988.
AIM: To screen the proteins that interact with the catalytic thiol-protein oxidoreductase (TPOR) domain of macrophage migration-inhibitory factor (MIF). METHODS: Yeast two-hybrid system was used to study the proteins that interacted with MIF. The bait vector pBTM116-MIF was constructed and transfected into L40 yeast strain. L40 competent cells expressing the TPOR domain were prepared and used to screen the proteins interacting with the TPOR domain of MIF in a human osteosarcoma cDNA library. The proteins interacting with TPOR domain were identified by HIS3 reporter gene and β-galactosidase assay. The techniques of co-immunoprecipitation and immunofluorescence were also used to verify the proteins interacting with TPOR domain. RESULTS: Wild-type pBTM116-MIF and pACT2-TXNL2 (thioredoxin-like 2 protein) were constructed and co-transfected into L40 yeast strain. The activation of HIS3 reporter gene and the positive result of β-galactosidase assay indicated that TXNL2 was the candidate protein that interacted with the catalytic TPOR domain of MIF. The vector of pcDNA3.1-Myc-TXNL2 was constructed and transfected into MCF-7 cell line. The result of co-immunoprecipitation assay showed that the catalytic TPOR domain of MIF co-immunoprecipitated with Myc-TXNL2 protein. The result of immunofluorescence assay demonstrated that the catalytic TPOR domain of MIF and TXNL2 co-localized in the cytoplasm of the cells. CONCLUSION: TXNL2 is the protein that interacts with the catalyzed TPOR domain of MIF.  相似文献   
989.
魏凯 《野生动物》2012,33(1):34-36
在金钱龟的人工养殖过程中,观察到部分个体发生了腐皮、肺炎、腹泻等疾病。通过对细菌的实验室诊断和生化特性鉴定,发现引起金钱龟腐皮和腹泻的病原体为嗜水气单胞菌,而肺炎则是由温度突变引起的感冒造成。因此,进一步研究了人工养殖条件下金钱龟的常见疾病与一些环境因子的关系。研究表明,温度差异对金钱龟的生理机能有显著的影响,而水质条件和养殖密度的调控也关系到金钱龟的健康生长,这也为金钱龟防治疾病及健康养殖模式提供一些参考依据。  相似文献   
990.
Effects of different carbohydrate sources on plasma glucose, insulin and insulin-like growth factor-I (IGF-I) levels were compared to subsequently be able to study effects of insulin-stimulating diets on follicle development in sows. The following feed components were tested in 12 sows during six consecutive test periods of 9.5 days: dextrose (DEX), sucrose (SUC), lactose (LAC), dextrose plus lactose (DL), sucrose plus lactose (SL), dextrose plus sugarbeet pulp (DSBP) and control (CON). On day 2, 5 and 9 of each test period, plasma glucose (only at day 9), insulin and IGF-I profiles were determined. Despite similar glucose profiles for all diets, the postprandial insulin response was higher for DL and SL compared with CON and LAC; the other diets were intermediate. Plasma IGF-I levels were higher in CON, LAC and SL compared with DSBP, but differences were only marginal. It was concluded that dextrose and sucrose have the potential to stimulate fast and high insulin peaks, especially when combined with additional lactose. Despite the high dextrose in the DSBP diet, the insulin response was flattened, probably due to the viscosity of sugarbeet pulp. The results show that modulation of plasma insulin levels by dietary carbohydrates seems possible in anabolic sows, but IGF-I levels are less easily modified.  相似文献   
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