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   19333篇
  免费   1578篇
  国内免费   642篇
耳鼻咽喉   171篇
儿科学   306篇
妇产科学   555篇
基础医学   2517篇
口腔科学   403篇
临床医学   2154篇
内科学   4049篇
皮肤病学   235篇
神经病学   1180篇
特种医学   470篇
外国民族医学   3篇
外科学   2624篇
综合类   1496篇
现状与发展   3篇
一般理论   5篇
预防医学   1061篇
眼科学   744篇
药学   1629篇
  6篇
中国医学   569篇
肿瘤学   1373篇
  2024年   24篇
  2023年   208篇
  2022年   375篇
  2021年   686篇
  2020年   449篇
  2019年   485篇
  2018年   568篇
  2017年   504篇
  2016年   491篇
  2015年   663篇
  2014年   803篇
  2013年   924篇
  2012年   1387篇
  2011年   1490篇
  2010年   885篇
  2009年   720篇
  2008年   1088篇
  2007年   1121篇
  2006年   1147篇
  2005年   1139篇
  2004年   919篇
  2003年   785篇
  2002年   773篇
  2001年   544篇
  2000年   535篇
  1999年   484篇
  1998年   190篇
  1997年   198篇
  1996年   165篇
  1995年   113篇
  1994年   113篇
  1993年   79篇
  1992年   213篇
  1991年   193篇
  1990年   168篇
  1989年   154篇
  1988年   117篇
  1987年   112篇
  1986年   91篇
  1985年   62篇
  1984年   43篇
  1983年   31篇
  1982年   45篇
  1981年   39篇
  1980年   35篇
  1979年   36篇
  1978年   32篇
  1977年   19篇
  1975年   20篇
  1973年   14篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
内置式下颌骨牵引成骨术及其常见并发症的处理   总被引:4,自引:12,他引:4  
目的 探讨内置式下颌骨牵引成骨术的常见术后并发症发生的原因及防治措施。方法 总结分析1997至2004年采用内置式下颌骨牵引成骨术治疗下颌骨畸形或缺损患者46例61侧,其中半侧颜面短小27例,下颌骨发育不足或小颌畸形双侧8例、单侧4例,电击伤或肿瘤术后缺损畸形3例,Treaeher Colins综合征2例,睡眠呼吸暂停综合征2例。结果 46例61侧发生并发症者9例,包括牵引机械装置故障3例,局部感染2例,前牙开骀2例,皮肤窦道2例。经积极处理后均达到预期治疗目的。结论 减少下颌骨牵引成骨术并发症的关键在于充分理解下颌骨牵引成骨术的机理,熟悉掌握下颌骨及邻近解剖结构,操作规范熟练,充分的术前准备和术后处理尤为重要。  相似文献   
992.
Aim: To review the evidence in using inflow occlusion during liver resection. Other strategies to minimize the untoward effects of inflow occlusion will also be discussed. Methods: Randomized trials evaluating the use of inflow occlusion in hepatectomy and strategies to minimize its associated adverse effects were reviewed in this article. Recent experience showing comparable operative outcomes without the use of portal clamping was also described. Results: Results from randomized trials and meta‐analyses were not conclusive on the benefits of routine inflow occlusion during liver resection. Intermittent inflow occlusion and ischaemic preconditioning had been found to be effective in reducing ischaemic–reperfusion injury to remnant liver. With refined operative techniques and better instruments, routine inflow occlusion in liver resection can now be safely avoided. Conclusion: Vascular inflow occlusion is an important armamentarium during liver resection, but it should not be used indiscriminately. With refined techniques and better instruments, hepatectomy can be performed safely without the need for routine inflow occlusion.  相似文献   
993.
INTRODUCTION: Our previous randomized clinical trial comparing the laparoscopic medial-to-lateral dissection with the more classic lateral-to-medial approach for resection of rectosigmoid cancer showed that the medial approach reduces the operative time and the postoperative proinflammatory response. Besides the oncologic advantages of an early vessel division and a "no-touch" dissection, we feel that the longer the lateral abdominal wall attachments of the colon are preserved, the better the exposure and the easier the dissection. Encouraged by the above-mentioned positive findings, we therefore further conduct this phase II clinical trial to examine the feasibility and surgical outcomes regarding the utilization of this medial-to-lateral laparoscopic dissection approach for the curative resection of right-sided colon cancer. METHODS: A total of 104 patients (from December 2000 to January, 2005) with advanced right-sided colon cancer (TNM stage II: n = 56; stage III: n = 48) requiring a curative right hemicolectomy were subjected to the laparoscopic medial-to-lateral approach that included initial exploration and ligation of ileocolic, right colic, and middle colic vessels in no-touch isolation fashion, subsequent medial-to-lateral extension of retroperitoneal dissection along Gerota fascia, opening of lesser sac by transection of gastrocolic ligament, and the final mobilization of hepatic flexure and lateral attachments of ascending colon (Fig. 1). This study was approved by the institutional review committee of National Taiwan University Hospital. The surgical details were shown in the video. Postoperatively, adjuvant chemotherapy with Mayo Clinic Regimen was given in patients with stage III diseases. The functional recovery and surgical outcomes were prospectively evaluated. RESULTS: The laparoscopic medial-to-lateral approach for a curative right hemicolectomy can be preformed with acceptable operation time (192.6 +/- 32.8 min, mean +/- standard deviation) and little blood loss (48.4 +/- 14.4 ml) through a small wound (6.0 +/- 0.8 cm). The number of dissected lymph node was 16.0 +/- 2.8. The operative complications represented 5.7% of all cases, including anastomotic leakage in two cases (1.9%) and wound infection in four cases (3.8%). The patients have quick functional recovery, as evaluated by the length of postoperative ileus (60.0 +/- 12.0 h), hospitalization (9.0 +/- 1.5 days) and degree of postoperative pain (4.0 +/- 0.5, visual analogue scale). Besides the expenses covered by the National Bureau of Health Insurance in Taiwan, the patient had to pay an extra-expenses of NT$ 25,000.0 +/- 2,800.0 (1.0 US$ = 32.0 NT$). During the follow-up periods (median: 30 months, range 6-55 months), recurrence of tumor developed in 6 (10.7%) of stage II and 10 (20.8%) of stage III patients, with liver metastasis in six patients, lung metastasis in 4, liver and lung metastasis in 1, intraperitoneal recurrence in 2, bone metastasis in 1, brain metastasis in 1, and port-site recurrence in 1. CONCLUSIONS: By medial-to-lateral dissection method, the laparoscopic right hemicolectomy can be performed with technical efficiency, short convalescence, and acceptable short-term oncologic results. We therefore encourage the use of this approach for patients requiring a curative laparoscopic right hemicolectomy.  相似文献   
994.
Li XX  Wang SM  Lai YH  Li SQ 《中华外科杂志》2005,43(23):1516-1518
目的探讨乳腺髓样癌临床特征、治疗和预后。方法回顾性分析1995年1月至1999年12月收治的乳腺髓样癌的临床资料。结果26例乳腺髓样癌占同期治疗女性乳腺癌616例的4.2%,年龄31~66(45.8±10.6)岁,肿瘤大小1~5 CM,腋淋巴结阳性率23.1%,腋淋巴结转移的发生与乳腺肿瘤的大小无关,免疫组化检测雌激素(ER)、孕激素(PR)和HER-2/NEU的阳性率分别为26.3%、21.1%和5.3%。全组进行手术和辅助化疗(环磷酰胺、甲氨蝶呤和氟尿嘧啶)。5例服用三苯氧胺,3例进行放射性治疗。随访时间5~9年,平均7.5年,总的5年生存率为88.4%。结论乳腺髓样癌的预后较好,手术加辅助性化疗是治疗的重要手段,分子生物学指标在乳腺髓样癌预后中的作用应该受到足够的重视。  相似文献   
995.
996.
目的探讨Sharpin蛋白在人不同前列腺癌细胞株中与前列腺癌组织中的表达及其与Gleason评分、血清PSA的关系。方法采用实时荧光定量PCR法,检测Sharpin在DUl45、PC-3和LNCaP3种常见的前列腺癌细胞株和RWPE.1正常前列腺上皮细胞株中的表达。同时采用免疫组织化学方法检测Sharpin在前列腺增生及前列腺癌组织中的表达,并探讨与临床病理特征的关系。结果Sharpin在3种前列腺癌细胞株中的mRNA水平(1.62±0.31,1.36±0.23,2.1±0.1)要明显高于正常前列腺上皮细胞RWPE-1(0.6±0.11)。免疫组织化学结果示Sharpin在前列腺癌组织中高表达,前列腺癌中的阳性表达率远远高于前列腺增生组织,平均染色得分也要远远高于前列腺增生组织。另外,Sharpin在前列腺癌组织中的表达与患者的Gleason评分和术前血清的t-PSA密切相关,均呈正相关(P〈0.05)。结论Sharpin可能是前列腺癌的肿瘤相关抗原,sharpin的表达可能具有评估前列腺癌患者病情、指导临床治疗方案的指导及判断预后及复发的作用。  相似文献   
997.
998.

Objectives

Our previous study noticed remarkably elevated titers of anti-high-mobility group box 1 (HMGB1) antibodies in sera during the tolerance induction phase of a rat tolerogenic orthotopic liver transplantation (OLT) as well as in sera of clinically drug-free patients. We hypothesized that the release of nonhistone nuclear protein HMGB1 during rejection may play a pathogenic role in deteriorating post-OLT graft functions, such as inducing liver fibrosis. This study sought to investigate whether HMGB1 can directly activate hepatic stellate cells (HSCs) and drive them toward fibrogenesis.

Methods

The cultured HSCs were treated with recombinant HMGB1. RT-PCR and Western blotting analysis were used to measure α-smooth muscle actin (α-SMA) expression. Conditioned media were collected for gelatin zymography to monitor the activities of collagen-degrading matrix metalloproteinases (MMPs).

Results

HMGB1 at concentrations >1 ng/mL significantly stimulated HSC growth as revealed by proliferation and BrdU assays. α-SMA gene and protein expression were significantly up-regulated by HMGB1, whereas the MMP-2, but not MMP-9, activity was suppressed by HMGB1 treatment.

Conclusion

Our data suggested that HMGB1 protein, once released during the rejection phase of OLT, activated HSCs and exhibited profibrogenic effects on liver grafts either by increasing the HSC population and extracellular matrix content in liver grafts, or by transforming HSCs into myofibroblasts. Neutralization with anti-HMGB1 antibody was suggested to be a therapeutic modality applicable to prevent fibrogenesis in post-OLT liver grafts.  相似文献   
999.
1000.
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