首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   38220篇
  免费   3271篇
  国内免费   1432篇
耳鼻咽喉   426篇
儿科学   859篇
妇产科学   441篇
基础医学   2852篇
口腔科学   1579篇
临床医学   4675篇
内科学   6740篇
皮肤病学   1167篇
神经病学   1650篇
特种医学   1714篇
外科学   2609篇
综合类   6643篇
现状与发展   10篇
一般理论   4篇
预防医学   5660篇
眼科学   926篇
药学   2654篇
  26篇
中国医学   1762篇
肿瘤学   526篇
  2024年   145篇
  2023年   798篇
  2022年   1685篇
  2021年   1935篇
  2020年   1869篇
  2019年   1401篇
  2018年   1322篇
  2017年   1255篇
  2016年   1489篇
  2015年   1317篇
  2014年   2587篇
  2013年   2734篇
  2012年   2359篇
  2011年   2533篇
  2010年   2066篇
  2009年   1961篇
  2008年   1859篇
  2007年   1887篇
  2006年   1588篇
  2005年   1480篇
  2004年   1155篇
  2003年   1039篇
  2002年   861篇
  2001年   835篇
  2000年   661篇
  1999年   494篇
  1998年   485篇
  1997年   392篇
  1996年   277篇
  1995年   349篇
  1994年   290篇
  1993年   192篇
  1992年   217篇
  1991年   196篇
  1990年   156篇
  1989年   164篇
  1988年   149篇
  1987年   142篇
  1986年   114篇
  1985年   95篇
  1984年   72篇
  1983年   43篇
  1982年   44篇
  1981年   28篇
  1980年   29篇
  1979年   37篇
  1978年   23篇
  1977年   26篇
  1976年   25篇
  1975年   18篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
子宫切除术对生存质量的影响   总被引:10,自引:0,他引:10  
目的:研究子宫切除术对生存质量的影响。方法:对108例因良性疾病而行腹式子宫切除术者进行前瞻性队列研究,术前及术后3,6,12个月进行调查问卷,观察症状、泌尿及胃肠功能、性功能、心理状况、社会生活状态的变化。结果:子宫切除术后3个月症状、压抑、焦虑程度减轻,社会生活状态显著提高,泌尿及胃肠功能、性功能无改变,这些改善持续至术后12个月。结论:子宫切除术可有效缓解妇科良性疾病所产生的症状,症状的缓解有利于改善生存质量。大多数因妇科良性疾病而行腹式子宫切除术的妇女,在术后1年,生存质量提高。  相似文献   
92.
目的 :通过分析比较结肠扫描不同充填剂与不同体位的方法 ,探讨出最佳充填剂与最佳体位以提高结肠 CT扫描质量。方法 :分别对 4 0例结肠 CT扫描病人采用不同的充填剂 ,与不同的体位 ,评价不同的充填剂与不同体位的优缺点。结果 :水作为充填剂组病灶显示情况明显优于泛影萄胺组且伪影少 ,选择不同体位组图像质量也明显优于常规体位组。结论 :结肠 CT扫描时应首选水作为充填剂 ,根据病变不同选择不同的体位 ,有利于图像质量的提高  相似文献   
93.
BACKGROUND: Larvae of insects and worms, used as live fish bait (LFB), are a common source of allergy in anglers and occupationally exposed workers, but the prevalence and predictors have not yet been investigated. OBJECTIVE: This study assessed the prevalence and associated factors of occupational allergy in workers exposed to LFB. METHODS: We assessed the prevalence of sensitization to LFB and work-related symptoms (WRS) in 76 workers occupationally exposed to it. All workers completed a case history questionnaire and underwent skin prick tests (SPT) for common aeroallergens and bluebottle (Calliphora vomitoria), bee moth (Galleria mellonella), mealworm (Tenebrio molitor), and gusano rojo (Cilecomadia moorei). Specific IgE were tested in 64 subjects. Two-thirds of the workers had a high level of LFB exposure. RESULTS: Sensitization to LFB was found in 24 workers (31.6%). Seven subjects (9.2%) reported WRS (asthma in 3, rhinoconjunctivitis in 5, and contact urticaria in 1), and 5 were positive for SPT and serum IgE to one or more LFB extracts. One was also exposed to LFB while fishing. Sensitization to LFB extracts and WRS were strongly associated (Odds Ratio = 6.6, P < 0.05). The 7 subjects with WRS had been exposed longer than asymptomatic subjects with positive skin tests to LFB (P < 0.05). No differences in sex, age, smoking habit, duration or level of exposure, and atopy were detected in symptomatic or in sensitized subjects, compared with normal workers. CONCLUSION: Sensitization to LFB and WRS are relatively frequent in occupationally exposed workers. No associated factors of occupational allergy to LFB could be detected.  相似文献   
94.
目的 探讨部队性病防治情况。方法 设计 10个与性病有关的问题 ,对随机抽样某师 4个营官兵现场无记名调查。结果 有关性病的基本知识已被大部分官兵所认知 ,但也有一部分官兵对性病缺乏了解 ,甚至误解。结论 在官兵中加强性病基本知识的宣传 ,强调性病的危害对部队防治性病很有必要。  相似文献   
95.
Nodular regenerative hyperplasia (NRH), a rare condition that is commonly associated with noncirrhotic portal hypertension, is not well described in the MR literature. Three patients at two institutions were identified who had both abdominal MR imaging and pathologic evidence of NRH. All examinations were performed at 1.5 T and included axial T1- and T2-weighted spin-echo (SE) images. The MR studies were reviewed by two radiologists in consensus. Two patients had multiple liver lesions that had high signal components on T1-weighted images and were predominantly isointense with liver on the T2-weighted images. One patient had no focal lesions identified. NRH, when visualized on MR images, appears as multifocal masses with shortened Tl and T2 similar to liver. NRH should be considered in the differential diagnosis of hepatocellular tumors, especially in patients with a predisposing condition.  相似文献   
96.
桂美辛组(男性21例,女性35例;年龄44±12a)治疗胆绞痛56例,剂量300mg, po, tid,显效32例,有效21例,总有效率95%。山茛菪碱组52例(男性18例,女性34例;年龄46±13a),剂量10mg, im, tid,显效、有效分别为9与20例,总有效率56%。2组比较,P<0.01。桂美辛治疗胆绞痛有疗效高、不良反应少的优点。  相似文献   
97.
Sexual, reproductive and venereal risk factors for cervical neoplasia were investigated in a population-based case-control study of 586 women with histologically verified, cervical squamous-cell carcinoma in situ, and 59 women with invasive squamous-cell cervical cancer, diagnosed from 1985 to 1986 in Copenhagen. Cases were identified from the computerized Danish Cancer Registry. An age-stratified control group (n=614) was drawn at random from the female population in the study area by means of the Danish Central Population Register. A structured questionnaire was mailed to cases as well as controls. Increasing number of sexual partners exerted a significant effect on the risk both for carcinoma in situ, and invasive cancer, independently of age at first intercourse and other potential confounders. Conversely, the association with early age at first intercourse became statistically insignificant after allowance for other risk factors, although an increasing risk was still observed with decreasing age at sexual debut. Early age at first episode with genital warts was a significant risk factor for carcinoma in situ, perhaps indicating a possible increased susceptibility of the cervix epithelium during adolescence. A history of genital warts was a good predictor of risk for carcinoma in situ, whereas a history of previous gonorrhea was associated with an increased risk for invasive carcinoma. Women with multiple births had a significantly increased adjusted risk, especially for carcinoma in situ, although some association was also observed with invasive cervical cancer. The study supports the hypothesis of cervical neoplasia being a sexually transmitted disease, and that carcinoma in situ and invasive cervical carcinoma, to a high degree, have similar patterns of risk factors.Drs Kjaer, Engholm, and Lynge are with the Danish Cancer Registry. Dr Dahl is with the Department of Surgery, Slagelse Hospital, Denmark. Dr Bock is with the Department of Gynecology, Rigshospitalet, Copenhagen, Denmark. Dr Jensen, formerly with the Danish Cancer Registry, is deceased. Address correspondence to Dr Kjaer, Danish Cancer Registry, Institute of Cancer Epidemiology, Danish Cancer Society, Rosenvengets Hovedvej 35, Box 839, Copenhagen. Denmark. The Danish Cancer Society supported this study through grants.  相似文献   
98.
The role of selected prior medical conditions in the etiology of hematopoietic malignancies was examined in a case-control study of members of two regional branches of the Kaiser Permanente Medical Care Program (USA). Past history of chronic infectious, autoimmune, allergic, and musculoskeletal disorders was abstracted from medical records for leukemia (n = 299), non-Hodgkin's lymphoma (NHL, n = 100), and multiple myeloma (n = 175) cases and matched controls (n = 787). Little difference was found between cases and controls for most of the chronic conditions evaluated, including sinusitis, carbuncles, urinary tract infections, pelvic infections, herpes zoster, asthma, rheumatoid arthritis, psoriasis, bursitis, and gout. Only three statistically significant elevated risks were found, i.e., with combined disc disease myeloma among patients with prior eczema and disk and other musculoskeletal conditions, and NHL following tuberculosis. Only two of these associations showed consistent patterns by sex and geographic region (myeloma with eczema and with musculoskeletal conditions). While prior history of eczema and musculoskeletal conditions may slightly increase risk of myeloma, this study provided little if any support for an association of chronic infectious, autoimmune, allergic, and musculoskeletal conditions with subsequent occurrence of the leukemias or NHL. Additionally, these data did not support a role for chronic antigenic stimulation, as defined in previous epidemiologic studies, in the etiology of hematopoietic malignancies.Ms Doody and Drs Linet, Pottern, Boice, and Fraumeni are with the Epidemiology and Biostatistics Program, National Cancer Institute. Dr Glass is with the Kaiser Permanente Medical Care Program, Northwest Region, Portland, Oregon, USA. Dr Friedman is with the Kaiser Permanente Medical Care Program, Northern California Region, Oakland, California, USA. Address correspondence to Ms Doody, Radiation Epidemiology Branch, National Cancer Institute, Executive Plaza North, Room 408, Bethesda, MD 20892, USA. This research was supported in part by National Cancer Institute contracts NO1-CP-01047, NO1-CP-01054, NO1-CP-11009, NO1-CP-11037, NO1-CP-31035, and NO1-CP-61006.  相似文献   
99.
广西百色地区肝病患者及受血者HCV感染现状调查   总被引:7,自引:0,他引:7       下载免费PDF全文
笔者应用ELISA法对广西百色地区179例各类肝病患者及41例受血者血清进行了抗-HCV检测。结果各类肝病抗-HCV阳性率为17.9%,受血者抗-HCV阳性率为31.7%。在急性肝炎(急肝)、慢性肝炎(慢肝)、肝硬化和肝癌中,抗-HCV阳性率各为4.3%(1/23)、12.8%(10/78)、28.6%(12/42)和25.0%(9/36)。抗-HCV阳性率有随肝病慢性比而增高的趋势,肝硬化的抗-HCV阳性率明显高于急肝或慢肝(P<0.05),而肝癌的抗-HCV阳性率与急肝或慢肝相差不显著(P>0.05或0.1),且发现HBsAg阴性肝病者的抗-HCV阳性率明显高于HBsAg阳性患者(P<0.5),肝病患者抗-HCV的检出率与ALT活性无关(P>0.05)。在受血者中,抗-HCV的检出率与受血次数、ALT活性关系非常密切。因此,加强对HCV的检测是当前预防输血后肝炎的紧迫任务。  相似文献   
100.
山西省卫Ⅳ项目地区农民因病致贫研究   总被引:4,自引:0,他引:4  
目的 研究项目地区农民因病致贫严重程度及预防措施。方法 利用扩展线性支出系统界定贫困标准,观察因病致贫率并研究因病致贫人群特点。结果 农民因病致贫率3.44%,因病致贫人群收入低,健康状况差,馒性病患病率高。2周就诊和年住院率高,年家庭医疗费用支出远高于对照人群。结论 通过住院医疗保险和慢性病防治措施缓解农民因病致贫。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号