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   279104篇
  免费   24226篇
  国内免费   17143篇
耳鼻咽喉   2561篇
儿科学   3455篇
妇产科学   5343篇
基础医学   31923篇
口腔科学   4856篇
临床医学   35523篇
内科学   44465篇
皮肤病学   3210篇
神经病学   14977篇
特种医学   9952篇
外国民族医学   109篇
外科学   30184篇
综合类   42099篇
现状与发展   62篇
一般理论   50篇
预防医学   18601篇
眼科学   7511篇
药学   28373篇
  208篇
中国医学   13478篇
肿瘤学   23533篇
  2024年   838篇
  2023年   3933篇
  2022年   9935篇
  2021年   13089篇
  2020年   9656篇
  2019年   8616篇
  2018年   9129篇
  2017年   8160篇
  2016年   7716篇
  2015年   11649篇
  2014年   14681篇
  2013年   13961篇
  2012年   20360篇
  2011年   22165篇
  2010年   13968篇
  2009年   11304篇
  2008年   14899篇
  2007年   14978篇
  2006年   14385篇
  2005年   14307篇
  2004年   10271篇
  2003年   9549篇
  2002年   8257篇
  2001年   7304篇
  2000年   6999篇
  1999年   7111篇
  1998年   4058篇
  1997年   4075篇
  1996年   3031篇
  1995年   2835篇
  1994年   2451篇
  1993年   1635篇
  1992年   2438篇
  1991年   2137篇
  1990年   1771篇
  1989年   1543篇
  1988年   1333篇
  1987年   1230篇
  1986年   994篇
  1985年   793篇
  1984年   509篇
  1983年   401篇
  1982年   236篇
  1981年   211篇
  1980年   195篇
  1979年   255篇
  1978年   147篇
  1977年   121篇
  1976年   104篇
  1974年   123篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
针对医学图像的模糊特点,结合模糊连接度,提出一种新的用模糊聚类分析检测圆弧的方法,它可以精确提取出圆弧.首先把曲线按一定长度进行分段处理,分别拟合出各段的圆心坐标和半径,通过模糊关系把具有一定相似性的聚为一类,把同一类中连续的段合在一起组成新段,再进行拟合,然后再对此段两端一定范围内寻找,直至找到最佳的圆弧.这种方法已应用到股骨头轮廓圆弧的提取.  相似文献   
83.
The use of low levels of visible or near infrared light for reducing pain, inflammation and edema, promoting healing of wounds, deeper tissues and nerves, and preventing cell death and tissue damage has been known for over forty years since the invention of lasers. Despite many reports of positive findings from experiments conducted in vitro, in animal models and in randomized controlled clinical trials, LLLT remains controversial in mainstream medicine. The biochemical mechanisms underlying the positive effects are incompletely understood, and the complexity of rationally choosing amongst a large number of illumination parameters such as wavelength, fluence, power density, pulse structure and treatment timing has led to the publication of a number of negative studies as well as many positive ones. A biphasic dose response has been frequently observed where low levels of light have a much better effect on stimulating and repairing tissues than higher levels of light. The so-called Arndt-Schulz curve is frequently used to describe this biphasic dose response. This review will cover the molecular and cellular mechanisms in LLLT, and describe some of our recent results in vitro and in vivo that provide scientific explanations for this biphasic dose response.  相似文献   
84.
Purpose Post operative monitoring is crucial for the success of microsurgical free tissue transfer. Sophisticated and expensive methods are available for monitoring. We propose a novel technique using digital photography and the internet as a reliable and cost effective method to monitor free tissue transfers. Methods 163 micro‐vascular procedures were monitored using this technique over 8 months. Serial photographs taken to show flap color. Capillary refill time, pin prick‐ bleed time and color and hand held Doppler signal was recorded in the movie mode of a standard 5 mega pixel camera with duration of 15 seconds. Data was sent to the surgeon at regular intervals and or as deemed necessary. Results Analysis of the 67 cases is presented. 5 re‐explorations were done. The early diagnosis of venous congestion was possible using this technique. Timely intervention contributed to the success of the re‐explorations and these flaps could be salvaged. The file size of images was in the range of 1 MB–6 MB. The file size of an entire set of images ranged about 7 MB–9 MB. These were sent across the ADSL internet lines. Conclusion The use of the digital images and the internet allow reconstructive surgeons to have a reliable picture of the state of their free tissue transfers. This permits decrease in observer error and saves valuable time which otherwise needs to be spent to verify situations of doubt and offers an ideal solution to the logistic problem of having to visit the patient in case of doubt.  相似文献   
85.
清开灵注射液治疗脑血管性痴呆32例   总被引:9,自引:0,他引:9  
目的观察清开灵注射液治疗脑血管性痴呆的疗效.方法将中医学辨证属于实证的64例脑血管性痴呆患者随机分为治疗组(清开灵注射液组)和对照组(脑复康组),治疗5周后,将两组治疗前后在智力障碍程度、肢体功能、血液流变学指标、中医证型疗效方面的变化进行比较.结果经治疗后治疗组和对照组相比较,智力障碍程度变化(有效率、MMSE、ADL积分)、肌力、步行能力改变有显著性差异,p<0.05.而治疗前后组内及组间血流变指标虽有一定下降,但无统计学意义(p>0.05).结论清开灵注射液对脑血管性痴呆患者,在改善智力障碍、肌力、步行能力方面有较好的疗效.  相似文献   
86.
87.
泰素蒂加顺铂治疗进展期NSCLC的临床研究   总被引:5,自引:0,他引:5  
目的观察泰素蒂加顺铂方案治疗进展期非小细胞肺癌的临床疗效、毒副作用。方法收集可评价疗效的进展期非小细胞肺癌50例,以泰素蒂加顺铂方案进行化疗,泰素蒂75 mg/m2静脉滴注,第1天;顺铂25 mg/m2~30 mg/m2静脉滴注,第2天~第5天,每3周为一个周期,2~3周期后评价疗效和毒副反应并随访。结果50例患者中,总有效率为50.0 %,其中初治病例为53.1 %,复治病例为44.4 %,初复治病例间差异无显著性(P >0.05)。中位缓解期为5个月。中位生存期为9.5个月,1年生存率为61.0 %。毒副反应主要为骨髓抑制,白细胞下降达Ⅲ度、Ⅳ度者52.0 %,血小板下降达Ⅲ度、Ⅳ度者为14.0 %。血红蛋白下降不严重。其他毒副反应还有脱发、过敏反应、水钠潴留、静脉炎、末梢神经炎、口腔炎、腹泻等,但发生率均较低。结论泰素蒂加顺铂方案治疗进展期非小细胞肺癌,特别是复发病例,临床疗效比较满意,毒副反应能够耐受。辅以G蛳CSF可防治重度的骨髓抑制,有较好的临床应用价值。  相似文献   
88.
The adequate treatment of methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis has intrigued clinicians for some time. As the resistance of these pathogens, coupled with the increase in community-acquired cases, continues steadily to rise, clinicians are finding it useful to employ multi-modal approaches for efficacious treatment. The authors present a single case report of a patient with recurrent MRSA osteomyelitis, lumbar paraspinal and epidural abscess. He was found to have decreased muscle strength and was hyporeflexic in the involved extremity. Serum testing demonstrated MRSA bacteremia. Neuroimaging studies revealed evidence of paraspinal abscess and a presumed herniated nucleus pulposus at the L5/S1 interspace with significant nerve root compromise. Despite antimicrobials, his symptoms persisted, necessitating surgical exploration. At surgery, paraspinal and epidural abscesses were encountered and debrided; however, no herniated disc was visualized. This case demonstrates the diagnostic and therapeutic dilemmas with which these lesions present. We postulate that the MRSA osteomyelitis/discitis pathogens were walled off in the disc space and subsequently inoculated the soft tissues with ensuing bacteremia. We concur that antimicrobial treatment should be the first line of therapy for these patients; however, surgical debridements and cautious spinal instrumentation should be employed where appropriate.  相似文献   
89.
High cord blood immunoglobulin E (cbIgE) is known to be associated with increased risks of atopic diseases in childhood. The relationship between genetic polymorphisms and high cbIgE has not been well documented. A cross-sectional study was conducted to assess the association between cbIgE and genetic polymorphisms of interleukin (IL)-4 -590C/T, the beta-subunit of the high-affinity receptor for IgE (FcepsilonRI-beta) E237G, lymphotoxin (LT)-alphaNcoI alleles, and tumor necrosis factor (TNF)-alpha -308G/A. A total of 320 mother-neonate pairs were recruited from four maternity hospitals from different locations of Taiwan. Cord blood was obtained and assayed for cbIgE. Polymerase chain reaction followed by restriction fragment length polymorphism was used to assess the genotypes. Three hundred pairs of mothers and neonates were included in the final analysis. Infants with IL-4 -590 C allele were found to have higher risk of elevated cbIgE (> or =0.35 IU/ml, 24.3%) (p = 0.004). After adjusting for gender, birth order, maternal age, and history of allergic disease in maternal and paternal families, odds ratios for CC and CT genotypes were 4.41 and 3.16 (95% confidence interval 0.78-22.67, and 1.66-6.13), respectively, using TT genotype as reference. The genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha were not associated with cbIgE before or after the adjustment. Our finding suggested a significant association of cbIgE with genetic polymorphism of IL-4 -590C/T, but not with the genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha.  相似文献   
90.
指背腱膜的解剖学研究   总被引:1,自引:1,他引:0  
目的 探讨指背腱膜的构成特点及临床意义。方法 在30只成人尸体手标本上,通过模拟手术,对指背腱膜的构成特点进行了应用解剖学观测。结果 指背腱膜的构成复杂,其中的外侧腱束、外侧束、外侧腱和中央束在手指畸形的发生中有着特殊的临床意义。外侧腱束主要形成伸近节指间关节的功能解剖机制;其与外侧束形成的密切纤维联系而具有协同外侧腱的功能;该腱束与屈肌腱鞘有联系又使其具有平衡屈肌和伸肌肌力的作用。中央束在指背腱膜的整体协调、畸形的发生及矫正过程中起着重要的功能。结论 通过对指背腱膜的解剖研究,可以解释因指屈、伸肌腱平衡被破坏后所形成的畸形。  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