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   524521篇
  免费   48135篇
  国内免费   37312篇
耳鼻咽喉   4601篇
儿科学   5412篇
妇产科学   7350篇
基础医学   64680篇
口腔科学   9087篇
临床医学   73200篇
内科学   75261篇
皮肤病学   5063篇
神经病学   29323篇
特种医学   19618篇
外国民族医学   342篇
外科学   52217篇
综合类   86367篇
现状与发展   118篇
一般理论   47篇
预防医学   31726篇
眼科学   15812篇
药学   55075篇
  549篇
中国医学   30295篇
肿瘤学   43825篇
  2024年   938篇
  2023年   6869篇
  2022年   11662篇
  2021年   25184篇
  2020年   19171篇
  2019年   17106篇
  2018年   18173篇
  2017年   16260篇
  2016年   15307篇
  2015年   23082篇
  2014年   28765篇
  2013年   25204篇
  2012年   37249篇
  2011年   42610篇
  2010年   26564篇
  2009年   20868篇
  2008年   28058篇
  2007年   28326篇
  2006年   28679篇
  2005年   28462篇
  2004年   18068篇
  2003年   16905篇
  2002年   14531篇
  2001年   12970篇
  2000年   14063篇
  1999年   15181篇
  1998年   9446篇
  1997年   9486篇
  1996年   7417篇
  1995年   6923篇
  1994年   5733篇
  1993年   3795篇
  1992年   4792篇
  1991年   4073篇
  1990年   3505篇
  1989年   3019篇
  1988年   2547篇
  1987年   2135篇
  1986年   1754篇
  1985年   1444篇
  1984年   837篇
  1983年   570篇
  1982年   352篇
  1981年   333篇
  1980年   257篇
  1979年   309篇
  1978年   89篇
  1977年   99篇
  1974年   110篇
  1973年   89篇
排序方式: 共有10000条查询结果,搜索用时 17 毫秒
41.
目的 探讨滋肾育胎丸加减方预防抗磷脂抗体(ACA)阳性者不良妊娠结局的效果及机制研究。方法 选取2016年2月至2019年2月我院收治的89例ACA阳性,先兆性流产或有习惯性流产(RSA)史患者,将采用西医治疗的40例作为对照组,将采用西医联合滋肾育胎丸加减方治疗的49例作为观察组,比较两组中医证候疗效、中医证候积分、ACA-IgA、ACA-IgM、ACA-IgG、凝血指标[血小板聚集功能(PAF)、活化蛋白C(PC)、抗凝血酶(AT)、纤溶酶原激活抑制物-1(PAI-1)]、Th1/Th2细胞因子[干扰素γ(IFN-γ)、白介素-2(IL-2)、白介素-4(IL-4)、白介素-10(IL-10)]、妊娠结局、安全性。结果 治疗2周后检测ACA,观察组2例未降低,对照组11例未降低,观察组未降低患者占比低于对照组(P<0.05);观察组总有效率100.00%高于对照组85.00%(P<0.05);观察组治疗4周、7周后中医证候积分低于对照组(P<0.05);观察组治疗4周、7周后ACA-IgA、ACA-IgM、ACA-IgG低于对照组(P<0.05);观察组治疗4周、7周后PAF、PAI-1低于对照组,PC、AT高于对照组(P<0.05);观察组治疗4周、7周后IFN-γ、IL-2低于对照组,IL-4、IL-10高于对照组(P<0.05);观察组活产率95.92%高于对照组80.00%(P<0.05);组间不良反应总发生率比较,差异无统计学意义(P>0.05)。结论 动态监测ACA对滋肾育胎丸加减方精准应用具有指导意义,指导滋肾育胎丸加减方通过调理脏腑、气血、经络功能,改善先兆性流产或有RSA史患者临床症状及凝血因子指标,降低ACA水平,并可改善患者免疫耐受功能,提高胎儿活产率,且安全性高。  相似文献   
42.
43.
Forgiveness has been found one substantial element in the recovery for women survivors from intimate partner violence following the termination of the abusive relationship. To further investigate the details of forgiveness in this specific context, the present study explored the process of forgiveness using grounded theory. In-depth and semi-structured interviews were conducted with 25 Chinese women survivors of IPV. The findings suggest that forgiveness is a strength-based process including empowerment, transformation, and integration phases. In the empowerment phase, survivors obtain strength at the intrapersonal, behavioural, and interpersonal levels. In the transformation phase, survivors complete cognitive transformation for their IPV experiences and emotional transformation towards former partners. In the integration phase, survivors—now freed from the past—reflect upon and apply the changes they have undergone. Two trajectories in the process were found. One trajectory is going through stages sequentially and the other trajectory is experiencing back and forth between empowerment and transformation stages before moving into the integration stage. The study's findings broaden our knowledge of the strength-based forgiveness process that women survivors of IPV undergo during recovery. Practitioners and policymakers could develop programmes and policies that support forgiveness by holistically facilitating their recovery and empowerment like assistance in dealing with life difficulties and promoting their reconnection with social networks. To improve the transferability and validity of the findings, the forgiveness of survivors of IPV could be explored in a diverse sample (e.g., survivors with low educational background or live in the rural area).  相似文献   
44.
45.
宫腔积液指宫腔内液体积存(积水、积血或积脓),是绝经后女性常见体征之一,常于超声检查时发现。持续宫腔积液患者,需宫腔镜检查寻找病因。本文报道1例以宫腔积液为首发症状,经宫腔镜检查确诊为胃型宫颈腺癌的患者。通过病例回顾并文献复习,以期为更多绝经后宫腔积液及宫颈病变的诊断提供参考,避免漏诊及误诊。1病例资料患者67岁,女,主因"绝经18年,不规则阴道出血2月"于2020年5月就诊于首都医科大学附属北京妇产医院妇科微创中心。  相似文献   
46.
目的:探讨姑息性胃切除联合术后化疗评分在腹膜转移的胃癌患者预后评估中的临床意义。方法:回顾性分析2010年1月至2016年12月7年间收治的287例发生腹膜转移的胃癌患者的临床病理资料。通过χ2检验分析评分与患者临床病理因素间的关系。通过Kaplan-Meier法绘制生存曲线,Log-rank检验比较患者生存率的差异;采用Cox比例风险回归模型对患者进行预后分析。结果:与评分中得分为2分和1分的患者相比,得分为0分的患者肿瘤侵润至T4b 期的患者较少[31%(18/58)比50.8%(63/124)、56.2%(59/105),P=0.039]。全组患者的中位生存时间仅为8.7月。对患者进行单因素预后分析结果显示,血清白蛋白浓度(≤40 g/L),腹水,腹膜转移范围较大,肿瘤T分期较晚,评分得分较高的患者预后较差(均P<0.05)。将上述因素纳入Cox多因素分析结果显示:评分[HR(95%CI):1.384(1.165~1.644),P=0.000],血清白蛋白浓度[HR(95%CI):0.759(0.593~0.971),P=0.028],肿瘤T分期[HR(95%CI):1.493(1.216~1.832),P=0.000]是患者预后的独立危险因素。结论:评分对于胃癌伴腹膜转移患者的预后生存评估具有重要的临床意义。  相似文献   
47.
Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H2O2. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability.  相似文献   
48.
目的了解不同丙戊酸负荷量对癫痫持续状态患儿的治疗效果。方法收集2013年1月1日至2017年12月31日在浙江大学医学院附属儿童医院重症监护室住院治疗的癫痫持续状态患儿的病例资料,根据丙戊酸负荷量进行分组,了解各组患儿癫痫持续状态的控制情况。结果(1)66例癫痫持续状态患儿,包括癫痫36例(54.5%),颅内感染16例(24.2%),缺氧窒息3例(4.5%),颅内肿瘤2例(3.0%),脑发育异常2例(3.0%),颅内出血2例(3.0%),病因不明确5例(7.6%)。(2)所有癫痫持续状态患儿根据不同的丙戊酸负荷量(0 mg/kg,10~15 mg/kg,16~39 mg/kg,40 mg/kg)分为4组,各组间的性别、年龄差异无统计学意义,癫痫持续状态控制时间和癫痫控制情况差异无统计学意义(P=0.402、0.340)。(3)所有患儿予丙戊酸钠应用后都有监测肝功能,无一例患儿出现肝功能损害的表现。结论不同丙戊酸负荷量对于癫痫持续状态患儿的治疗效果无明显差异,并且接受负荷量为40 mg/kg治疗的癫痫持续状态患儿未出现相关不良反应。  相似文献   
49.
MicroRNAs (miRNAs) play important roles in prostate cancer development. However, it remains unclear how individual miRNAs contribute to the initiation and progression of prostate cancer. Here we show that a basal layer‐enriched miRNA is required for prostate tumorigenesis. We identify miR‐205 as the most highly expressed miRNA and enriched in the basal cells of the prostate. Although miR‐205 is not required for normal prostate development and homeostasis, genetic deletion of miR‐205 in a Pten null tumor model significantly compromises tumor progression and does not promote metastasis. In Pten null basal cells, loss of miR‐205 attenuates pAkt levels and promotes cellular senescence. Furthermore, although overexpression of miR‐205 in prostate cancer cells with luminal phenotypes inhibits cell growth in both human and mouse, miR‐205 has a minimal effect on the growth of a normal human prostate cell line. Taken together, we have provided genetic evidence for a requirement of miR‐205 in the progression of Pten null‐induced prostate cancer.  相似文献   
50.
Objective: The objective of this study is to evaluate the efficacy and safety of the clearing the lung and dissipating phlegm method in the treatment of acute exacerbation of chronic obstructive pulmonary disease(COPD) and to provide evidence for the treatment of the disease. Materials and Methods: Literature was searched from the United States National Library of Medicine(PubMed), Embase, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database(Wanfang), and the Full?Text Database of Chinese Scientific and Technical Periodicals(VIP).A comprehensive collection was made of randomized controlled trials(RCTs) before June 2018, in which the treatment groups used either the clearing the lung and dissipating phlegm formulas only or combined it with routine Western medicine therapy, and the control group adopted routine Western medicine therapy only for the acute exacerbation of COPD. The Cochrane risk of bias method was used to evaluate the quality of the literature. The data were analyzed and retrieved independently by two reviewers before meta?analysis was carried out with RevMan 5.3 software to evaluate the primary outcome measures, including the total clinical effective rate, and the secondary outcome measures such as the pulmonary function(forced vital capacity [FVC], forced expiratory volume in the 1 s [FEV1], percentage of FEV1 [FEV1%], and FEV1/FVC)and blood gases(PaO_2 and PaCo_2). Results: A total of 13 RCTs involving 990 patients(496 in the treatment group and 494 in the control group)were included in this study. Meta?analysis revealed significant difference in the efficacy of the group that adopted solely the routine Western medicine method and the group that combined the Western medicine with the clearing the lung and dissipating phlegm method. Outcome measures including the pulmonary function(FVC, FEV1, FEV1%, and FEV1/FVC) and the blood gases(PaO_2 and PaCo_2) were significantly improved as compared to the control group(P 0.00001). However, adverse effects in the treatment group using combined traditional Chinese medicine were not reported due to the short observation time of the study. Conclusion: The clearing the lung and dissipating phlegm method can improve the efficacy in the treatment of acute exacerbation of COPD, the outcome measures of the pulmonary function and the blood gases,as well as the life quality of the patients. However, due to the fact that the existing studies are generally of poor quality in which randomization and its implementation were not properly carried out, more high?quality RCTs are necessary to confirm the findings of this study.  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