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   200138篇
  免费   37729篇
  国内免费   2478篇
耳鼻咽喉   5653篇
儿科学   6736篇
妇产科学   3558篇
基础医学   10905篇
口腔科学   2683篇
临床医学   33022篇
内科学   56172篇
皮肤病学   7989篇
神经病学   19741篇
特种医学   8334篇
外国民族医学   57篇
外科学   47232篇
综合类   1326篇
现状与发展   73篇
一般理论   50篇
预防医学   12810篇
眼科学   4540篇
药学   4868篇
中国医学   65篇
肿瘤学   14531篇
  2023年   4936篇
  2022年   1418篇
  2021年   3781篇
  2020年   6433篇
  2019年   2873篇
  2018年   8138篇
  2017年   7903篇
  2016年   9015篇
  2015年   9112篇
  2014年   16501篇
  2013年   17269篇
  2012年   7773篇
  2011年   7850篇
  2010年   11690篇
  2009年   15394篇
  2008年   8014篇
  2007年   6308篇
  2006年   8801篇
  2005年   6028篇
  2004年   5355篇
  2003年   4095篇
  2002年   4084篇
  2001年   5338篇
  2000年   4669篇
  1999年   4631篇
  1998年   4278篇
  1997年   4017篇
  1996年   3865篇
  1995年   3727篇
  1994年   2427篇
  1993年   1999篇
  1992年   2505篇
  1991年   2570篇
  1990年   2139篇
  1989年   2239篇
  1988年   2080篇
  1987年   1788篇
  1986年   1806篇
  1985年   1612篇
  1984年   1305篇
  1983年   1151篇
  1982年   945篇
  1981年   811篇
  1980年   756篇
  1979年   1006篇
  1978年   877篇
  1977年   870篇
  1976年   700篇
  1973年   699篇
  1972年   705篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
122.
Background Hydatid disease is the most severe helminthic zoonosis, with an important public health problem especially in rural areas in Turkey. The aim of this study was to review the problems and advantages encountered in surgical treatment of 43 patients who were ventilated with one-lung ventilation during last four years. Methods Patients, operated with one-lung ventilation, constitute the study group. Data related to symptoms, radiographic findings, performed surgical procedures, perioperative and postoperative morbidity, hospitalization time, and cyst recurrence were collected from each individual's records. Results Cystotomy and capitonnage were performed in all cases. Perioperative complications were seen in 5 patients. Four of these 5 patients had double-lumen endotracheal tube malpositioning. In one patient hypoxemia developed. The most common postoperative complication was atelectasis. One patient had recurrent cysts. There was no perioperative or postoperative death. Conclusions We prefer cystotomy and capitonnage because it is a fast and effective technique with limited postoperative complications. One-lung ventilation prevents the exposure of lower lung areas from massive aspiration, which may cause acute obstruction of airways, and contamination by cyst contents from the operative part of the lung that causes recurrent disease. One-lung ventilation in pulmonary hydatid cyst surgery may be preferred owing to lower mortality and morbidity rates.  相似文献   
123.
SONI NANDA  MD    VINEET RELHAN  MD    CHANDER GROVER  MD  DNB  MNAMS    B.S.N. REDDY  MD  MNAMS 《Dermatologic surgery》2006,32(3):387-392
BACKGROUND: Suction blister epidermal grafting is an established technique for the treatment of resistant and stable vitiligo especially over small and cosmetically important areas like the face. However, certain areas, such as lips and eyelids, require special considerations because of their anatomic peculiarities. PATIENTS AND METHODS: The current study was carried out on six patients of stable eyelid vitiligo, not responding to medical treatment. Suction blister was obtained from the thigh using the suction apparatus and the roof was grafted on to the dermabraded eyelid. Certain precautions were taken during the procedure, which will be highlighted in the current study. RESULTS: Response was excellent in all the patients in 3 to 6 months, with no complications. CONCLUSIONS: If carried out properly, suction blister technique is the procedure of choice for cosmetically important sites like eyelids.  相似文献   
124.
Genetically modified keratinocytes and fibroblasts are suitable for delivery of therapeutic genes capable of modifying the wound healing process. However, efficient gene delivery is a prerequisite for successful gene therapy of wounds. Whereas adenoviral vectors (Ads) exhibit superior levels of in vivo gene transfer, their transductional efficiency to cells resident within wounds may nonetheless be suboptimal, due to deficiency of the primary adenovirus receptor, coxsackie-adenovirus receptor (CAR). We explored CAR-independent transduction to fibroblasts and keratinocytes using a panel of CAR-independent fiber-modified Ads to determine enhancement of infectivity. These fiber-modified adenoviral vectors included Ad 3 knob (Ad5/3), canine Ad serotype 2 knob (Ad5CAV-2), RGD (Ad5.RGD), polylysine (Ad5.pK7), or both RGD and polylysine (Ad5.RGD.pK7). To evaluate whether transduction efficiencies of the fiber-modified adenoviral vectors correlated with the expression of their putative receptors on keratinocytes and fibroblasts, we analyzed the mRNA levels of CAR, alpha upsilon integrin, syndecan-1, and glypican-1 using quantitative polymerase chain reaction. Analysis of luciferase and green fluorescent protein transgene expression showed superior transduction efficiency of Ad5.pK7 in keratinocytes and Ad5.RGD.pK7 in fibroblasts. mRNA expression of alpha upsilon integrin, syndecan-1 and glypican-1 was significantly higher in primary fibroblasts than CAR. In keratinocytes, syndecan-1 expression was significantly higher than all the other receptors tested. Significant infectivity enhancement was achieved in keratinocytes and fibroblasts using fiber-modified adenoviral vectors. These strategies to enhance infectivity may help to achieve higher clinical efficacy of wound gene therapy.  相似文献   
125.
126.
127.
128.
129.
Hydration and Cognitive Function in Children   总被引:3,自引:0,他引:3  
Adequate fluid intake is critical for survival. While adults are at liberty to drink fluids as wanted, children and infants are dependent upon caregivers for food and fluid. Children are at greater risk for dehydration than adults due to their higher surface-to-mass ratio. Additionally, children have different thirst sensitivities and body cooling mechanisms than adults. Children differ from adults in total body water content, and boys and girls differ in body water content with maturation. Research in young adults shows that mild dehydration corresponding to only 1% to 2% of body weight loss can lead to significant impairment in cognitive function. Dehydration in infants is associated with confusion, irritability, and lethargy; in children, it may produce decrements in cognitive performance.  相似文献   
130.
BACKGROUND AND PURPOSE: Dot-like low intensity spots (dot-like hemosiderin spots: dotHSs) on gradient echo T2*-weighted MRI have been histologically diagnosed to represent old cerebral microbleeds associated with microangiopathies. They have also been correlated to the fragility of small vessels and the tendency to bleed. Therefore, a substantial number of dotHSs might be associated with a large-sized, deep intracerebral hematoma (ICH). On the other hand, dotHSs may reflect old microbleeds that did not enlarge to symptomatic size. METHODS: To investigate how dotHSs are related to the size (maximal diameter) of primary deep ICH, we analyzed the diameter and the number of dotHSs in 151 patients with deep ICH not associated with subarachnoid hemorrhage or intraventricular hemorrhage (75 males and 76 females, age ranged from 37 to 90 [65.7 +/- 11.3 years old] who were consecutively admitted to Hakodate Municipal Hospital. The hazard ratio (HR) for a maximal diameter of deep ICH < or =2 cm was estimated, using the number of dotHSs and risk factors for stroke. RESULTS: The number of dotHSs associated with the diameter < or =2 cm was 9.2 +/- 11.5, significantly larger than that with the diameter > or =2 cm (4.7 +/- 7.0, P= .012). Multivariate analysis revealed that a maximal diameter of deep ICH of < or =2 cm was found in patients with dotHS (HR, 3.7; 95% confidence interval [CI], 1.4-10.1; P= .009). CONCLUSION: Though small sample size limited the power of our analyses, these findings suggest that the number of dotHSs may be associated with a small diameter of deep ICH.  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