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九江市HIV-流行毒株基因序列测定和亚型分析   总被引:1,自引:0,他引:1  
目的:了解九江市HIV-1流行毒株的亚型分布情况。方法:对采集的6份九江市HIV-1感染者的血浆样品进行RT—PCR扩增,获得GAG基因的核酸片断进行核苷酸序列分析。结果:在6份样品中发现B’亚型HIV-1毒株四株,B亚型和A/E重组亚型HIV-1毒株各一株。结论:HIV-1流行毒株亚型在九江市分布情况复杂,防控形势严峻。  相似文献   
124.
性途径感染HIV是世界范围内传播HIV的主要途径,也是目前中国HIV感染的主要方式[1].虽然近年经吸毒途径感染HIV的病例所占比例出现下降趋势,但吸毒人群至今仍是我国艾滋病防治的重要人群之一.虽然女性吸毒者仅占我国吸毒总人数的20.0%,在深圳等沿海地区约占40.0%[2,3],但其总数及所占比例近年都呈快速增长的趋势[4].另外,与男性吸毒者相比,女性具有特殊的吸毒行为及特征;女性吸毒者中有较高比例的卖淫行为(通过出卖性获取金钱或毒品),导致多性伴和无保护性行为等高危性行为特征,可加速HIV通过性途径继续传播的速度.  相似文献   
125.
Liang H  Xing H  Li JZ  Wei M  Hong KX  Feng Y  Zhao QB  Chen JP  Quan Y  Teng T  Shao YM 《中华医学杂志》2005,85(13):897-902
目的鉴定我国HIV-1主要流行毒株亚型的env,V3-V4区及其临近区域的特征性氨基酸,并阐明其在追踪传染源和研究疫苗中的作用。方法应用nested—PCR对157份来自我国12个省份的HIV-1毒株env区序列进行扩增,并使用ABI377型测序仪测序,然后应用BLAST、GCG、MEGA和VESPA等生物学软件或程序对env基因V3-V4区及其临近区域序列进行基因型鉴定、系统树分析及特征性氨基酸鉴定。结果157份样本包括54份B′(34.40%)、61份B′/C(38.85%)和42份CRF01-AE(26.75%)毒株。系统树分析结果显示,B′亚型毒株序列均与B.CN.RL42十分接近,B′/C毒株主要与97CN54A和97CNGX6F聚成一簇。而CRF01—AE序列与THCM240和97CNGX2F聚在一起.而且分别聚成明显不同的两个亚组。特征性氨基酸分析发现,我国B′和B′/C毒株分别具有8个保守的特征性氨基酸,而且与代表株的相同位点氨基酸基本一致。而CRF01-AE重组毒株具有11个保守的特征性氨基酸,其中有9个位点与97CNGX2F和TH.CM240不一致。包括这9个特征性氨基酸的样本主要来自除云南省以外的其他省份。结论目前流行于我国的B′和B′/C毒株具有单一的共同传染源,而CRF01-AE毒株可能是通过不同输入源或不同传播途径先后从泰国传入我国的。这将对我国艾滋病防治策略的制定和正在进行的疫苗研究具有重要的指导意义。  相似文献   
126.
The purpose of the study was to determine breast and cervical cancer screening among women living in the Mississippi Delta region. Using data from the Behavioral Risk Factor Surveillance System for 1999--2000, we determined the prevalence of mammography (women 40 years and older, n = 6,028) and Pap testing (women 18 years and older, n = 6,502) within the past 2 or 3 years, respectively. We examined predictors of testing and compared results with those for women living elsewhere in the United States. Among Delta women, 69.4% (95% confidence interval [CI] 67.9% to 70.9%) had a mammogram and 85.5% (95% CI 84.3% to 86.6%) a Pap test. Mammography prevalence was lower among black and white Delta women than among black and white women elsewhere. Pap testingwas lower among older (65 years and older) Delta women or women who did not visit a doctor within the past year than among their counterparts elsewhere. Additional interventions are needed to meet the goals of Healthy People 2010 for all women.  相似文献   
127.
Increasing infectious disease deaths, the emergence of new infections, and bioterrorism have made surveillance for infectious diseases a public health concern. Medical examiners and coroners certify approximately 20% of all deaths that occur within the United States and can be a key source of information regarding infectious disease deaths. We hypothesized that a computer-assisted search tool (algorithm) could detect infectious disease deaths from a medical examiner database, thereby reducing the time and resources required to perform such surveillance manually. We developed two algorithms, applied them to a medical examiner database, and verified the cases identified against the opinion of a panel of experts. The algorithms detected deaths with infectious components with sensitivities from 67% to 94%, and predictive value positives ranging from 8% to 49%. Algorithms can be useful for surveillance in medical examiner offices that have limited resources or for conducting surveillance across medical examiner jurisdictions.  相似文献   
128.
The gag-based heteroduplex mobility assay (gag-HMA) was evaluated for its ease and reliability in subtyping circulating recombinant forms (CRFs) of human immunodeficiency virus type 1 (HIV-1) in C?te d'Ivoire. One hundred thirty-two plasma samples were analyzed blindly for HIV-1 subtypes by sequencing the pol gene and by gag-HMA. DNA sequencing was used as the "gold standard." Of the 132 samples sequenced, 108 (82%) were CRF02_AG, 14 (11%) were pure subtype A, 5 (4%) were subtype G, 3 (2%) were subtype D, 1 was CRF01_AE, and 1 was subtype H. The gag-HMA correctly classified 126 (95.5%) of the samples. Of the 108 samples that were classified as CRF02_AG by DNA sequencing, 107 (99%) were correctly identified by gag-HMA, resulting in a positive predictive value of 96.4%. The gag-HMA seems to be a valuable tool for understanding the molecular epidemiology of HIV-1 CRF02_AG in C?te d'Ivoire and West Africa, which could be important for developing and evaluating AIDS vaccines, although DNA sequencing remains necessary for accurate molecular epidemiology.  相似文献   
129.
OBJECTIVES: We measured the extent to which a set of psychosocial health problems have an additive effect on increasing HIV risk among men who have sex with men (MSM). METHODS: We conducted a cross-sectional household probability telephone sample of MSM in Chicago, Los Angeles, New York, and San Francisco. RESULTS: Psychosocial health problems are highly intercorrelated among urban MSM. Greater numbers of health problems are significantly and positively associated with high-risk sexual behavior and HIV infection. CONCLUSIONS: AIDS prevention among MSM has overwhelmingly focused on sexual risk alone. Other health problems among MSM not only are important in their own right, but also may interact to increase HIV risk. HIV prevention might become more effective by addressing the broader health concerns of MSM while also focusing on sexual risks.  相似文献   
130.
HIV/AIDS-associated and non-HIV/AIDS-associated death rates and causes of death between 1993 and 1999 were examined in 885 HIV-infected women and 425 uninfected women of the HIV Epidemiology Research Study cohort. Causes of death were determined by review of death certificates and the National Death Index. Adjusted bazard ratios were calculated for mortality risk factors. In the 885 HIV-infected women and 425 uninfected women, 234 deaths and 8 deaths, respectively, occurred by December 31, 1999. All-cause death rates in the HIV-infected women were unchanged between the pre-HAART (1993–1996) and HAART eras (1997–1999) —5.1 versus 5.4 deaths per 100 person-years (py). AIDS as a cause of death decreased from 58% of all deaths in 1996 to 19% in 1999, while HAART use increased to 42% by the end of 1999. In spite of the modest proportion ever using HAART, HIV-related mortality rates did decline, particularly in women with CD4+cell counts less than 200/mm3. Drug-related factors were prominent: for the 129 non-AIDS-defining deaths, hepatitis C positivity (relative bazard [RH] 2.6, P<0.001) and injection drug use (RH 1.7, P=0.02) were strong predictors of mortality, but were not significant in the Cox model for 105 AIDS-defining deaths (RH 0.9, P>30 and RH 0.7, P>.30, respectively. The regression analysis findings, along with the high percentage of non-AIDS deaths attributable to illicit drug use, suggest that high levels of drug use in this population offset improvements in mortality from declining numbers of deaths due to AIDS. Supported by cooperative agreements No. U64/CCU106795, U64/CCU206798, U64/CCU306802, and U64/CCU506831 with the Centers for Disease Control and Prevention including supplementary support from the National Institute on Drug Abuse. Centers for Disease Control and Prevention, Division of HIV  相似文献   
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