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   9215篇
  免费   673篇
  国内免费   24篇
耳鼻咽喉   113篇
儿科学   253篇
妇产科学   188篇
基础医学   1549篇
口腔科学   175篇
临床医学   1053篇
内科学   1937篇
皮肤病学   265篇
神经病学   778篇
特种医学   327篇
外科学   1302篇
综合类   85篇
一般理论   9篇
预防医学   676篇
眼科学   154篇
药学   520篇
中国医学   8篇
肿瘤学   520篇
  2023年   58篇
  2022年   75篇
  2021年   197篇
  2020年   151篇
  2019年   213篇
  2018年   215篇
  2017年   194篇
  2016年   233篇
  2015年   230篇
  2014年   287篇
  2013年   417篇
  2012年   589篇
  2011年   579篇
  2010年   289篇
  2009年   276篇
  2008年   515篇
  2007年   479篇
  2006年   458篇
  2005年   445篇
  2004年   486篇
  2003年   416篇
  2002年   383篇
  2001年   165篇
  2000年   164篇
  1999年   150篇
  1998年   106篇
  1997年   95篇
  1996年   109篇
  1995年   87篇
  1994年   72篇
  1993年   69篇
  1992年   120篇
  1991年   93篇
  1990年   115篇
  1989年   110篇
  1988年   106篇
  1987年   84篇
  1986年   84篇
  1985年   97篇
  1984年   54篇
  1983年   75篇
  1982年   66篇
  1981年   76篇
  1980年   41篇
  1979年   43篇
  1978年   55篇
  1977年   56篇
  1976年   55篇
  1975年   51篇
  1974年   44篇
排序方式: 共有9912条查询结果,搜索用时 15 毫秒
1.
ABSTRACT

Measuring hope reliably and accurately remains an important research objective, not least in less prosperous settings where ‘holding on to hope’ may be critically important in the struggle against adverse life conditions. The State Hope Scale was designed for use in the US. Despite reported application in diverse cultures and using translations the scale has not been extensively validated outside US populations. This study contributes to a larger project exploring the measurement of hope and provides a critique of Snyder’s scale as used in a Tanzanian female population of 1021 urban microfinance participants. We evaluate the scale’s validity through assessment of the empirical distribution of scores, item response profiles, internal consistency and discriminatory ability. Participants mostly scored very high and many reached very near the maximum attainable score. Hardly any endorsed the negative half of the response scale. Several problems are discussed including poor discrimination and strong evidence of acquiescence response bias. We also found little association of the scale scores with hypothesised correlates of hope. Future improvements on the measurement of hope are recommended, especially in studies outside the narrow Western context in which the scale was devised.  相似文献   
2.
3.
4.
5.
For 50 years now, sacrospinous ligament fixation (SSLF) has been used to treat pelvic organ prolapse consequent on altered integrity of the pelvic myofascial structures. It is usually performed vaginally, but it has recently been performed laparoscopically through either an anterior or a posterior approach, with the broad ligament as a landmark to differentiate the two. In the present study, these two laparoscopic approaches were assessed using Thiel-embalmed cadavers. The anterior and posterior approaches were compared in terms of the closest distance to anatomical structures at risk, including pelvic viscera, the obturator nerve, and vascular structures. The posterior approach was more often closer to the investigated vessels and the rectum. The obturator nerve and the ureter were close to both the anterior and posterior approaches. The urinary bladder was closer using the anterior approach. From an anatomical standpoint, therefore, the anterior laparoscopic approach for SSLF is more likely to cause injury to the urinary bladder, whereas the posterior approach is more prone to causing rectal and vessel injuries. This study illustrates, from a basic science perspective, the importance of combining fascia research, novel endoscopic or minimally invasive surgical exposures informed by anatomy, and contemporary trends in gynecology in order to improve patient outcomes. Clin. Anat. 33:522–529, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
6.
7.
To measure prefrontal and subcortical activity during a cognitive task, we examined 19 newly diagnosed schizophrenics and patients with schizophreniform psychosis. Seven healthy volunteers served as controls. The patients were drug naive or had received neuroleptics for a few days only. Cerebral blood flow distribution was depicted by single photon emission computed tomography at rest and during activation with the Wisconsin Card Sorting Test. A significant relative activation deficit in the left inferior-prefrontal region was revealed during the Wisconsin Card Sorting Test in the patient group. Furthermore, the patients had impaired striatal suppression on the left side during the cognitive task. The test performance was significantly impaired in the patients. The inability to reduce striatal activity may be due to a lack of corticostriatal feedback during prefrontal activation.  相似文献   
8.
A F Holm  M J Staal  J J A Mooij  F W J Albers 《Otology & neurotology》2005,26(3):425-8; discussion 428
BACKGROUND: Tinnitus is an uncomfortable symptom for the patient and an embarrassing one for the consulted physician. So far, there is no treatment that can be considered well established in terms of providing long-term reduction of tinnitus in excess of placebo effects. There is considerable evidence of pathophysiological similarity between tinnitus and chronic pain. Some forms of chronic pain can be treated by neurostimulation. OBJECTIVE: This study was designed to investigate the feasibility of neurostimulation of the cochlear nerve in order to reduce tinnitus. STUDY DESIGN: Pilot study. SETTING: Tertiary referral center. PATIENTS: Five patients with therapeutically refractory tinnitus were selected for this study. INTERVENTION: Placing a stimulation lead around the cochlear nerve through the suboccipital approach and connecting the stimulation lead to a pulse generator. MAIN OUTCOME MEASURES: The patients experienced 1) an absence of major or minor complications, such as death, meningitis, cranial nerve deficit, and vestibular problems; 2) tolerance of the procedure as considered by the patient; 3) relief of tinnitus in at least one patient. RESULTS: Implantation of the neurostimulation system was accomplished in each patient without any difficulty. None of the patients considered the treatment unbearable. No major or minor complications occurred in this study. Subjective tinnitus reduction was accomplished in four patients. CONCLUSION: Our preliminary data show that neurostimulation of the cochlear nerve is feasible, is bearable for the patient, and is a safe treatment modality without major complications. The effects on tinnitus are promising.  相似文献   
9.
Direct (intraarterial) and two indirect (using a mercury sphygmomanometer [MS] and an automatic [auscultatory] device) methods of blood pressure measurement were compared in intensive care patients (N = 32). One trained observer blind to both automatic and direct measurements obtained all indirect MS measurements. All direct and indirect measurements were made on the same arm. Direct measurements were obtained from 10-second strip chart recordings. In normotensive patients both indirect measurements of systolic blood pressure (SBP) underestimated the direct SBP; however, only the SBP value obtained with the automatic device (106 mm Hg) was significantly different, p less than .05, from the direct SBP value (120 mm Hg). No significant difference was noted between methods in measurement of normotensive diastolic blood pressure. In hypertensive patients direct SBP was significantly greater, p less than .05, from both values obtained by indirect measurement. In patients without hypotension the automatic device may be substituted for the MS and direct blood pressure methods. The automatic device may offer the advantage of decreasing observer bias and variability in blood pressure measurement.  相似文献   
10.
We report our experience with elastic stable intramedullary titanium nailing (ESIN) of femoral shaft fractures in children. From 1998 to 2001, we treated 31 children (20 boys), median age 6 (4-11) years, with ESIN for 29 closed and 2 grade I open femoral shaft fractures. We reviewed 30 children clinically after median 1.5 (1-3) years. Their median hospital stay was 6 (2-20) days. All fractures were radiographically united at a median of 7 (5-9) weeks. The nails were removed in 29 children after a median of 22 (6-38) weeks postoperatively. At follow-up, we found a leg-length discrepancy up to 1 cm in 6 children and 10 degrees of internal rotational deformity in 1 child. No angular deformity had occurred. Elastic stable intramedullary nailing seems to be a safe method for the treatment of femoral shaft fractures in children between 4 and 11 years of age.  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