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51.
目的构建+10Gz重复暴露大鼠脑差异表达基因的消减cDNA文库。方法本实验用SD大鼠,分别提取暴露组与对照组的总RNA,并分离纯化mRNA,应用抑制性消减杂交技术分离+10GI重复暴露大鼠脑差异表达基因eDNA片段并建立消减eDNA文库;利用PCR对随机挑选的75个白色菌落进行插入片段的验证,对其中70个克隆进行eDNA斑点杂交验证。结果所构建的eDNA文库扩增后包含约400个白色克隆和100个兰色克隆,随机挑选75个白色克隆入质粒载体后共获得70个阳性克隆。结论应用抑制性消减杂交技术成功构建了+10Gz重复暴露大鼠脑差异表达基因消减eDNA文库,为进一步筛选和克隆脑损伤相关基因奠定了基础。  相似文献   
52.
Graph algorithms previously developed by the authors are adapted to simulate pedigrees similar to those used in genetic linkage studies which associate disease phenotypes with specific genomic locations. Pedigrees are chosen uniformly at random from the set of those with specified numbers of individuals and matings and which contain no loops. Summary statistics from pedigrees generated in this way can be used to check real pedigrees for anomalies due to biased sampling or phenotypic effects on the pedigree structure.  相似文献   
53.
BACKGROUND: Immunotherapy with anti-IgE antibodies for treatment of allergy is promising but a short half-life and extremely high cost limit its application. OBJECTIVE: We sought to develop IgE vaccines that induce longer-lasting auto-antibodies to neutralize self-IgE as an alternative therapy. METHODS: The vaccine was made by conjugating three synthetic peptides corresponding to human IgE receptor-binding sites to a carrier, hepatitis B surface antigen. To test the immunogenicity of the vaccine, rats were immunized with the vaccine or hepatitis B surface antigen as control. Serum IgG titres to human IgE and the IgE of other species were measured. The inhibition by rat antisera of the binding of human IgE to its receptor was assessed by ELISA, flow cytometry analysis, and passive cutaneous anaphylaxis (PCA), and its ability to recognize receptor-bound IgE was examined. The in vivo effect of the vaccine was evaluated in trichosanthin-sensitized mice and rats. In the preventative study, vaccination started before sensitization commenced, while in the treatment study, vaccination started after sensitization. Sensitized mice and rats receiving injections of the carrier served as controls. Trichosanthin-specific IgE was measured using PCA. RESULTS: Sera from vaccine-immunized rats contained high titre antibodies that reacted with soluble and plate-bound but not with receptor-bound human IgE; they also reacted with mouse, rat, and dog IgE. Furthermore, the sera inhibited the binding of human IgE to its receptor in a dose-dependent manner. In preventative and treatment studies, serum trichosanthin-specific IgE levels were significantly reduced in vaccinated groups compared with controls. CONCLUSION: Antibodies against self-IgE can be induced by IgE peptide-based vaccines, which are effective in preventing the increase of IgE and in down-regulating IgE in sensitized animals.  相似文献   
54.
采用微量乙肝疫苗(总剂量为6μg)对HBV高流行区居民进行随机对照研究,免疫Ⅰ组(疫苗<8℃保存)T12抗体阳转率和保护率分别为90.8%和87.0%,和对照组相比,差异显著(P均<0.001);和常规剂量(总剂量90μg)比,其抗体阳转率和保护率基本相同。提示HBV高流行区可用微量乙肝苗代替常量乙肝苗进行预防接种。免疫Ⅰ组和免疫Ⅱ组(乙肝疫苗室温保藏28℃±)免疫效果和保护率基本相同,认为室温条件下乙肝疫苗6个月内效价不变。  相似文献   
55.
重组酵母乙肝疫苗免疫效果研究   总被引:36,自引:0,他引:36  
目的研究重组酵母乙肝疫苗对青少年学生的免疫效果。方法同时对365名乙肝病毒血清学指标(HBV-M)不同感染状况的学生进行免疫监测。随机分为两组,A组:183人,接种剂量10-5-5(μg),B组:182人,接种剂量5-5-5(μg),用ELISA法,在全自动酶标分析仪上测定。结果1.重组酵母乙肝疫苗对青少年免疫效果良好,抗-HBs阳性率达97%以上;2.对HBV-M不同感染状况的学生,免疫后均无不良反应。结论HBV易感者和感染者接种疫苗后免疫效果均好。在青少年中普种乙肝疫苗可不筛查HBV-M。  相似文献   
56.
Abstract: Genetic hemochromatosis (GH) is closely associated with genes of the major histocompatibility complex (MHC) on chromosome 6. Recently, a candidate gene for GH, with structural similarities to MHC class I genes, designated HLA-H and presently named HFE, has been cloned. The HFE gene is localized telomeric to the MHC and several reports have indicated that the HFE gene is mutated in GH patients. In the present study we have analyzed the relationship of HFE gene variants and disease manifestation in GH patients and family members. Fifty-seven patients with GH, 73 family members and 153 healthy blood donors were studied for the amino acid dimorphism at codon 63 (His63Asp=H63D) and codon 282 (Cys282Tyr= C282Y) of the HFE gene. The codon 63 and 282 dimorphism were defined by PCR amplification of genomic DNA samples and restriction enzyme digestion using RsaI/SnaBI for C282Y and Bcll/Mbo 1 for H63D. Ferritin, transferrin serum levels and total iron-binding capacity were determined prior to therapeutic intervention. The Tyr-282 substitution occurred in 53 (93%) of patients compared with 8 (5.2%) of controls (OR=169, P >0.0001). Fifty-one (90%) patients were Tyr-282 homozygous. In contrast, the Asp-63 substitution was present in 5 (8.8%) of the patients compared with 34 (22%) of controls (OR=0.39, P =NS) with none of the patients being homozygous. In Tyr-282 homozygous GH patients serum ferritin levels, transferrin saturation, liver iron and liver iron index were elevated significantly compared to Tyr-282-negative patients, whereas no difference was observed between Tyr/Cys-282 heterozygous and Tyr-282-negative patients.  相似文献   
57.
Female mosquitofish (Gambusia affinis) were collected from two sites located on the US Department of Energy's Oak Ridge Reservation that are contaminated with 137Cs, 90Sr, other radionuclides and chemical genotoxicants. Fish from non- radionuclide contaminated environments located off the reservation were also collected. DNA, extracted from liver tissue and blood cells, was examined by gel electrophoresis for structural damage in the form of strand breakage. In general, the level of DNA strand breaks was elevated in fish from radionuclide-contaminated sites with observed differences in the number and type of strand breaks between liver tissue and blood cells. The number of malformed embryos was higher in fish at the contaminated sites, and varied with season. Fecundity was negatively correlated with the level of double strand breaks in the DNA of fish from one contaminated site. Females with broods that included malformed embryos had more DNA strand breakage than those that did not; and furthermore, a threshold effect was observed between the occurrence of malformed embryos and the presence of double strand breaks in the DNA of the mother. These findings have implications for both ecological risk assessment and evolutionary ecology  相似文献   
58.
The risk estimates for individual carriers of ten different familial reciprocal translocations detected among 500 couples with reproductive failures are presented. These were established by application of the empirical data analysed by Stengel-Rutkowski et al. (1988) and the guidelines given in Stene & Stengel-Rutkowski (1988). Different risks were estimated for unbalanced offspring at birth or at second trimester prenatal diagnosis for abortions, or stillbirths/early deaths. These risk estimates varied considerably from translocation to translocation. Carriers of five translocations had risks for offspring with single-segment imbalances. The birth risk figures ranged from 0.1% to 13.8%. Carriers of five other translocations had risks for double-segment imbalances with birth risks ranging from 0% to 3.2%. The estimated risk figures were independent of the method of ascertainment. Among the parents of the index cases we found nine maternal carriers and only one paternal carrier. This presentation illustrates the need for individual risk counselling of each carrier with reciprocal translocation regarding further family planning.  相似文献   
59.
水痘疫苗接种的成本效益   总被引:4,自引:0,他引:4  
水痘是一种常见的急性、高传染性的疾病 ,可感染儿童、成人。 1974年日本首先研制成功Oka株水痘减毒活疫苗 ,1984年世界卫生组织批准水痘减毒活疫苗用于婴幼儿预防接种 ,许多国家陆续开展了水痘疫苗预防接种 ,不仅能取得良好的防病效果 ,而且可较大地减轻疾病负担。对儿童、青少年、成人、育龄期妇女和免疫功能抑制患者分别进行的经济学评价表明 ,接种水痘疫苗具有较好的成本效益结果。  相似文献   
60.
《Movement disorders》2003,18(11):1240-1249
The identification of disease genes using family‐based approaches has provided important insights into the pathogenesis of Parkinson's disease (PD) demonstrating the importance of genetic studies on monogenic forms of the disease. We studied a large Cuban family with typical, late‐onset PD and probable autosomal dominant inheritance. Mean age at onset was 61.2 years (±12.53, 45–76). Other phenotypes such as essential tremor and atypical parkinsonism were observed in this family. We carried out a genome‐wide scan and linkage analyses. The genetic data were analyzed using a conservative model in which only patients with clinically definite or likely PD were considered affected, other phenotypes were regarded as “unknown.” Multipoint analyses yielded a maximum LOD of 2.26 between markers D19S221 and D19S840. Haplotype analysis showed a region on chromosome 19 shared by six of seven PD patients. The essential tremor phenotype and the atypical parkinsonism do not segregate with this haplotype, suggesting a different etiology. Our findings suggest the presence of a novel locus for PD on chromosome 19p13.3–q12. We propose that an oligogenic model with moderate contribution of two or three genes rather than a “pure” monogenic model might explain better the wide range in age at onset, the reduced penetrance and the phenotypical variability observed in PD families. © 2003 Movement Disorder Society  相似文献   
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