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   32642篇
  免费   2662篇
  国内免费   1242篇
耳鼻咽喉   430篇
儿科学   461篇
妇产科学   537篇
基础医学   2248篇
口腔科学   190篇
临床医学   2724篇
内科学   2541篇
皮肤病学   214篇
神经病学   433篇
特种医学   1596篇
外国民族医学   33篇
外科学   9675篇
综合类   5382篇
现状与发展   2篇
预防医学   692篇
眼科学   80篇
药学   1538篇
  7篇
中国医学   284篇
肿瘤学   7479篇
  2024年   81篇
  2023年   358篇
  2022年   700篇
  2021年   1042篇
  2020年   1015篇
  2019年   969篇
  2018年   920篇
  2017年   956篇
  2016年   1038篇
  2015年   1181篇
  2014年   1935篇
  2013年   1715篇
  2012年   1594篇
  2011年   2030篇
  2010年   1804篇
  2009年   1834篇
  2008年   1842篇
  2007年   1983篇
  2006年   1964篇
  2005年   1669篇
  2004年   1508篇
  2003年   1336篇
  2002年   1185篇
  2001年   1107篇
  2000年   826篇
  1999年   614篇
  1998年   549篇
  1997年   472篇
  1996年   338篇
  1995年   270篇
  1994年   286篇
  1993年   174篇
  1992年   168篇
  1991年   140篇
  1990年   131篇
  1989年   85篇
  1988年   96篇
  1987年   92篇
  1986年   76篇
  1985年   84篇
  1984年   68篇
  1983年   53篇
  1982年   57篇
  1981年   30篇
  1980年   38篇
  1979年   39篇
  1978年   37篇
  1977年   18篇
  1975年   12篇
  1973年   11篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Interstitial cystitis/bladder pain syndrome (IC/BPS) and vulvodynia are chronic pain syndromes that appear to be intertwined from the perspectives of embryology, pathology and epidemiology. These associations may account for similar responses to various therapies.  相似文献   
2.
目的探讨依维莫司联合全反式维甲酸(简称维甲酸)逆转急性早幼粒细胞白血病(APL)细胞株NB4-R1耐药的作用。方法应用CD11b染色流式细胞术及硝基四唑氮蓝(NBT)还原实验检测两药联合应用对细胞分化的影响, 流式细胞术检测细胞周期情况, Annexin V/PI双染色检测细胞凋亡情况, 蛋白质印迹法检测自噬相关蛋白微管结合蛋白轻链3(LC3)、Beclin 1及早幼粒白血病-维甲酸受体融合蛋白(PML-RARα)、磷酸化核糖体S6激酶(P-P70S6K)、磷酸化4E结合蛋白1(P-4E-BP1) 等表达水平。结果与维甲酸组比较, 联用组能诱导耐药细胞株NB4-R1细胞的分化, 并将细胞增殖阻止在G 1期而对细胞凋亡无明显影响。100 nmol/L依维莫司组、1μmol/L维甲酸组、联用组、对照组NB4-R1细胞培养48 h后分化百分率分别为(2.29±0.57)%、(17.06±2.65)%、(54.47±4.91)%、(2.54±0.53)%; 处于G 1期的细胞百分率分别为(35.20±11.97)%、(33.54±6.25)%、(53.70±8.73)%、(27.40±6.01)%; 四组细胞凋亡细胞百分率分别为(2.30±0.14)%、(2.25±0.21)%、(2.40±0.28)%、(1.95±0.07)%。与维甲酸组比较, 联用组mTOR信号通路下游的P70S6K、4E-BP1分子磷酸化水平下降, LC3-II和Beclin 1的表达上调, 且能部分降解融合蛋白PML-RARα。 结论依维莫司联合维甲酸能诱导NB4-R1细胞分化, 且能阻滞细胞周期而不致细胞凋亡, 其机制可能与依维莫司联合维甲酸抑制mTOR信号通路激活自噬作用从而降解PML-RARα蛋白有关。  相似文献   
3.
Objective: The objective of this study was to gain greater insight into individuals’ quality of life (QOL) definitions, appraisals, and adaptations following spinal cord injury (SCI).

Design: A mixed-methods design, applying the Schwartz and Sprangers response shift (RS) model. RS is a cognitive process wherein, in response to a change in health status, individuals change internal standards, values, or conceptualization of QOL

Setting: Community-dwelling participants who receive medical treatment at a major Midwestern medical system and nearby Veterans’ Affairs hospital.

Participants: A purposive sample of participants with SCI (N?=?40) completed semi-structured interviews and accompanying quantitative measures.

Interventions: Not applicable.

Outcome Measures: Qualitative data were analyzed using content analysis to identify themes. Analysis of variance were performed to detect differences based on themes and QOL, well-being, and demographic and injury characteristics.

Results: Four RS themes were identified, capturing the range of participant perceptions of QOL. The themes ranged from complete RS, indicating active engagement in maintaining QOL, to awareness and comparisons redefining QOL, to a relative lack of RS. Average QOL ratings differed as a function of response shift themes. PROMIS Global Health, Anxiety, and Depression also differed as a function of RS themes.

Conclusion: The RS model contextualizes differences in QOL definitions, appraisals, and adaptations in a way standardized QOL measures alone do not.  相似文献   

4.
Most ureteral tumors are transitional cell neoplasms. Neuroendocrine tumors of the genitourinary tract are extremely rare. To our knowledge, only one ureteral carcinoid tumor has been reported before. We report a second case of ureteral carcinoid tumor found in a 70-year-old female.  相似文献   
5.
The aim of this study was to examine the predictors of long-term survival (>24 months) in patients with gall bladder cancer. A retrospective review of 117 cases of gall bladder cancer resected between 1989 and 2000. The resections included 80 simple cholecystectomies and 37 extended procedures. Patients with survival >24 months (n=44) were compared with those having survival <24 months (n=73) for 17 prognostic factors. Overall median survival was 16 months with a 5-year survival of 27%. T status (P=.000) and adjuvant chemoradiotherapy (P=.001) were independent predictors of long-term survival. Survival advantage was seen in T3N+ve disease (P=.007) with extended procedures. Complete (R0) resection was attained in 30 patients with a 5-year survival advantage of 30% as compared with incomplete (R1) resection (P=.0002). Adjuvant chemoradiotherapy improved survival in simple cholecystectomy group (P=.0008) but no advantage was seen after extended procedures. Stage III (P=.001) and node-positive disease (P=.0005) had significant benefit with adjuvant therapy. Poor differentiation and vascular invasion were associated with poor long-term survival. R0 resection was associated with prolonged survival. Extended procedures improved survival in patients with T3N+ve disease. Addition of chemoradiotherapy made significant improvement in long-term survival in stage III and node-positive lesions and in patients undergoing simple cholecystectomy. R0 resection predicted long-term survival in gall bladder cancer. T3 N+ve disease had better survival after extended procedures. Adjuvant chemoradiotherapy improved survival in stage III and node-positive disease. Poor differentiation and vascular invasion were adverse predictors of survival.  相似文献   
6.
PTEN及Bcl-2蛋白在膀胱移行细胞癌中的表达及其意义   总被引:1,自引:0,他引:1  
乔宝民  孙光  畅继武  韩瑞发  王文成  马腾骧 《天津医药》2006,34(12):844-845,I0004
目的:探讨PTEN及Bcl-2蛋白在膀胱移行细胞癌的表达规律及其临床意义。方法:应用免疫组织化学链亲和素-生物素-霉复合物(SP)方法检测43例膀胱移行细胞癌和7例正常黏膜组织中PTEN及Bcl-2蛋白的表达.分析二者的表达与膀胱癌病理参数的关系。结果:(1)G1、G2、G3肿瘤PTEN表达阳性率分别为85.7%、80.4%、73.3%,浸润性肿瘤和表浅性肿瘤表达阳性率分别为70.4%和93.8%,说明PTEN表达阳性率与肿瘤病理分级、临床分期有关。(2)G。、G2、G3肿瘤Bcl-2表达阳性率分别为14.2%、57.14%、66.67%,浸润性肿瘤和表浅性肿瘤表达阳性率分别为59.3%和43.8%,说明Bcl-2表达阳性率与肿瘤病理分级、临床分期有关。(3)随着肿瘤恶性程度的增高和临床分期进展,PTEN蛋白阳性率呈下降,Bcl-2表达呈增高趋势,二者表达呈负相关关系。结论:PTEN的抑癌作用可能与Bcl-2有关.二者的异常表达在膀胱移行细胞癌的发生、发展过程中起重要作用。二者同时检测有助于判断预后。  相似文献   
7.
目的探讨中原地区遗传性非息肉病性大肠癌(HNPCC)的表型特征,为制订适合我国国情的HNPCC遴选标准提供依据。方法对符合Am sterdam标准的8个家系37例患者的临床资料(A组),与随机抽调我院40例确切无家族史的大肠癌患者的临床资料(B组)进行对比分析。结果①发病年龄:A组平均46岁,B组62.6岁,平均提前16.6年;<50岁者:A组73%(27/37),B组30%(12/40),两组比较P<0.01;第1、2、3代平均发病年龄分别为69.2、46.9、34.6岁,逐代比较差异有统计学意义(P<0.05或P<0.01)。②发病部位:右半结肠A组73.2%(30/41),B组39.0%(16/41),两组比较P<0.05。③同时、异时多发大肠癌:A组8.1%(3/37),B组2.5%(1/40)。④大肠外癌:A组17.1%(7/41),B组0,两组比较P<0.05。⑤合并腺瘤:A组0,B组22.5%(9/40),两组比较P<0.05。⑥组织学类型:低分化腺癌A组69.7%(23/33),B组40%(16/40),两组比较P<0.05。结论中原地区HNPCC有其独特的临床特征,国际遴选标准不能完全适用于中国人,制定适合我国国情的HNPCC遴选标准确有必要。  相似文献   
8.
Primary malignant melanoma of the bladder   总被引:1,自引:0,他引:1  
Primary malignant melanomma of bladder is extremely rare: 18 cases are reported to date. An 82 year-old man underwent trans-urethral resection of bladder for a bleeding tumor of the posterior wall. Histological diagnosis was melanoma of the bladder. There was no history of previous or regressed cutaneous malignant melanoma. Margins of the bladder lesion contained atypical melanocytes similar to those commonly seen in the periphery of primary mucous membrane lesions. Clinical studies and radiological examinations were negative for other primary site of melanoma. The patient had a bladder recurrence that was consistent with primary tumor and died of widespread disease 9 months after diagnosis.  相似文献   
9.
10.
Abstract  Gastrointestinal stromal tumor (GIST) is a recently described mesenchymal tumor that can develop in any portion of the gastrointestinal tract. The occurrence of a GIST in the urinary tract is rare, but GIST can present as tumor of the urinary tract or invade the urinary tract. This is the first reported case of GIST in the ileal neobladder, which presented as a submucosal tumor. The patient underwent an open exploration and partial resection of the neobladder pouch.  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