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   1666篇
  免费   78篇
  国内免费   6篇
耳鼻咽喉   16篇
儿科学   178篇
妇产科学   71篇
基础医学   182篇
口腔科学   26篇
临床医学   92篇
内科学   286篇
皮肤病学   45篇
神经病学   122篇
特种医学   38篇
外科学   224篇
综合类   29篇
预防医学   116篇
眼科学   151篇
药学   75篇
中国医学   11篇
肿瘤学   88篇
  2023年   7篇
  2022年   26篇
  2021年   32篇
  2020年   14篇
  2019年   14篇
  2018年   39篇
  2017年   13篇
  2016年   30篇
  2015年   34篇
  2014年   56篇
  2013年   90篇
  2012年   106篇
  2011年   139篇
  2010年   73篇
  2009年   50篇
  2008年   97篇
  2007年   98篇
  2006年   119篇
  2005年   113篇
  2004年   82篇
  2003年   96篇
  2002年   92篇
  2001年   31篇
  2000年   28篇
  1999年   29篇
  1998年   14篇
  1997年   13篇
  1996年   14篇
  1995年   14篇
  1994年   13篇
  1993年   9篇
  1992年   15篇
  1991年   20篇
  1990年   14篇
  1989年   13篇
  1988年   9篇
  1987年   5篇
  1986年   12篇
  1985年   7篇
  1984年   10篇
  1983年   9篇
  1980年   5篇
  1977年   9篇
  1976年   3篇
  1975年   3篇
  1971年   2篇
  1970年   4篇
  1969年   5篇
  1968年   2篇
  1967年   2篇
排序方式: 共有1750条查询结果,搜索用时 15 毫秒
61.

Objective

An awake craniotomy facilitates radical excision of eloquent area gliomas and ensures neural integrity during the excision. The study describes our experience with 67 consecutive awake craniotomies for the excision of such tumours.

Methods

Sixty-seven patients with gliomas in or adjacent to eloquent areas were included in this study. The patient was awake during the procedure and intraoperative cortical and white matter stimulation was performed to safely maximize the extent of surgical resection.

Results

Of the 883 patients who underwent craniotomies for supratentorial intraaxial tumours during the study period, 84 were chosen for an awake craniotomy. Sixty-seven with a histological diagnosis of glioma were included in this study. There were 55 men and 12 women with a median age of 34.6 years. Forty-two (62.6%) patients had positive localization on cortical stimulation. In 6 (8.9%) patients white matter stimulation was positive, five of whom had responses at the end of a radical excision. In 3 patients who developed a neurological deficit during tumour removal, white matter stimulation was negative and cessation of the surgery did not result in neurological improvement. Sixteen patients (24.6%) had intraoperative neurological deficits at the time of wound closure, 9 (13.4%) of whom had persistent mild neurological deficits at discharge, while the remaining 7 improved to normal. At a mean follow-up of 40.8 months, only 4 (5.9%) of these 9 patients had persistent neurological deficits.

Conclusion

Awake craniotomy for excision of eloquent area gliomas enable accurate mapping of motor and language areas as well as continuous neurological monitoring during tumour removal. Furthermore, positive responses on white matter stimulation indicate close proximity of eloquent cortex and projection fibres. This should alert the surgeon to the possibility of postoperative deficits to change the surgical strategy. Thus the surgeon can resect tumour safely, with the knowledge that he has not damaged neurological function up to that point in time thus maximizing the tumour resection and minimizing neurological deficits.  相似文献   
62.
Apraxia of speech (AOS) is a rare, but well-defined motor speech disorder. It is characterized by irregular articulatory errors, attempts of self-correction and persistent prosodic abnormalities. Similar to aphasia, AOS is also localized to the dominant cerebral hemisphere. We report a case of Crossed Aphasia with AOS in a 48-year-old right-handed man due to an ischemic infarct in right cerebral hemisphere.  相似文献   
63.

Aims:

To evaluate clinical profile and short-term outcome of psychogenic non-epileptic seizures (PNES) in Indian adult population.

Setting and Design:

A prospective observational study, conducted at tertiary teaching institute at New Delhi.

Materials and Methods:

Sixty-three patients with confirmed PNES were enrolled. The diagnosis was based on witnessing the event during video-electroencephalography (Video-EEG) monitoring. A detailed clinical evaluation was done including evaluation for coexistent anxiety or depressive disorders. Patients were divided into two groups on the basis of excessive or paucity of movements during PNES attacks. Patients were followed-up to 12 months for their PNES frequency.

Statistical Analysis:

Means and standard deviations were calculated for continuous variables. Chi-square and Students t-test were used to compare categorical and continuous variables respectively.

Results:

The mean age at onset of PNES was 25.44 years; with F:M ratio of 9.5:1. Coexistent epilepsy was present in 13 (20.63%) cases. Twenty-two patients (44%) with only PNES (n = 50) had received antiepileptic drugs. Out of 63 patients of PNES 24 (38.1%) had predominant motor phenomenon, whereas 39 (61.9%) had limp attacks. The common features observed were pre-ictal headache, ictal eye closure, jaw clenching, resistant behavior, ictal weeping, ictal vocalization, and unresponsiveness during episodes. Comorbid anxiety and depressive disorders was seen in 62.3% and 90.16% patients, respectively. Short-term (6-12 months) outcome of 45 patients was good (seizure freedom in 46.66% and >50% improvement in 24.44% cases).

Conclusion:

PNES is common, but frequently misdiagnosed and treated as epileptic seizures. A high index of suspicion is required for an early diagnosis. Proper disclosure of diagnosis and management of the psychiatric comorbidities can improve their outcome.

Limitation:

Limited sample size and change in seizures frequency as the only parameter for the assessment of the outcome are the two major limitations of our study.  相似文献   
64.

Background

Caregivers of adolescents diagnosed with Oppositional Defiant Disorder and/or Conduct Disorder (ODD/CD) experience unique challenges when interacting with child service systems involved in their adolescents’ care. Absent from the literature are interventions to improve these interactions, which in the long term may improve adolescent behavioral health outcomes.

Objective

To examine feasibility/acceptability of Family Management Efficacy (FAME) intervention content, structure, delivery, and appropriateness of selected measures for caregivers of African American adolescents with ODD/CD. Secondary aim was to explore changes in FAME caregivers’ interaction self-efficacy, stress, quality of life, and family functioning scores relative to caregivers receiving treatment as usual (TAU).

Method

A pilot two-group randomized trial was conducted with caregivers of African American adolescents (ages 12–18 years) diagnosed with ODD/CD receiving FAME (n?=?11) or TAU (n?=?9). Feasibility outcomes of enrollment/attrition, measurement completion, session attendance, and homework completion were assessed using tracking logs and field notes, and acceptability through caregiver satisfaction scores and interviews. Preliminary outcomes were assessed at baseline, post- and 2-months post intervention.

Results

FAME was highly acceptable and met a priori thresholds for feasibility in enrollment (56%), attrition (35%), caregiver attendance (55%), and homework completion (50%), with lower than anticipated kin attendance (42%) and measurement completion (55%). Preliminary outcomes suggest FAME may benefit caregivers in areas of family communication, cohesion, and quality of life, but lacked observed benefit for self-efficacy and problem solving indicating need for refinement.

Conclusion

Results inform changes to FAME content, measurement, and delivery schedule in preparation for a fully powered randomized controlled trial.
  相似文献   
65.
Objectives Studies examining risk factors for preterm birth (PTB) such as psychosocial stress are often focused on women with a history of PTB; however, most preterm babies are born to women with no history of preterm birth. Our objective was to determine if the relationship between psychosocial stress and PTB is altered by parity. Non-Hispanic black (NHB) women have increased psychosocial stress and PTB; therefore, we further aimed to determine if race alters the relationship between psychosocial stress, parity, and PTB. Methods We performed a secondary analysis of the Healthy Pregnancy, Healthy Baby Study comparing pregnant women who were primiparous (first pregnancy), multiparous with history of preterm birth, or multiparous with history of term birth. Perceived stress, perceived racism, interpersonal support, John Henryism and self-efficacy were measured using validated instruments. Logistic regression was used to model the effect of psychosocial stress on PTB stratified by parity and race. Results The analysis entire cohort included 1606 subjects, 426 were primiparous, 268 had a history of presterm birth, and 912 had a history of term birth. In women with a history of term birth, higher self-efficacy was associated with lower odds of spontaneous PTB, and this association was amplified in NHB women. In women with a history of spontaneous PTB, John Henryism Active Coping was associated with lower odds of spontaneous PTB in the index pregnancy. Conclusions for Practice The relationship between psychosocial stress and PTB may be mediated by parity and race.  相似文献   
66.
This study investigated the hypothesis that coating eroded teeth with a resin-based dentin bonding agent gave protection from tooth wear. Nineteen adults with palatal tooth wear exposing dentin were recruited, following referral by their general dental practitioner. Alternate teeth were coated with the resin adhesive, while the uncoated teeth acted as controls. Accurate impressions of the eroded teeth, onto which were cemented machined stainless steel discs to act as reference areas, were scanned with a non-contacting laser profilometer at 3, 6, 12 and 24 months. The mean thickness of resin at baseline application was 0.15 mm and, from 0 to 6 months, the rate of wear of the control teeth was higher than those covered with Seal & Protect. There was a statistically significant difference in "wear" measured between resin covered and control teeth at three months. The Inter Class Correlations (repeated measurements) for the step heights obtained for the original and repeat impressions was excellent at 0.99. This study shows that coating eroded teeth with a resin-based adhesive has the potential to prevent further tooth wear.  相似文献   
67.
68.
In light of the adverse reports of Bisphenol A (BPA) on reproduction and considering the pivotal role played by the steroid receptors (SRs) and their coregulators in male reproduction, it was of interest to decipher the influence that BPA may have on their expression pattern during critical ’windows‘ of development. Male rats were injected with 2.4 µg per pup per day of BPA from postnatal days (PND) 1–5 and controls received vehicle. During development, the testicular expression pattern of SRs (AR, ERβ and ERα), coactivators (SRC‐1, SRC‐2 and SRC‐3) and corepressors (NCoR and SMRT) in BPA‐exposed rats were compared. A significant decrease in the expression of SRs was seen in the BPA group. SRC‐1 showed a significant decrease, whereas SRC‐2 and SRC‐3 showed a significant increase in the protein expression whereas corepressor expression remained unaltered in the BPA‐exposed groups. Such impairments in the expression pattern can be a putative mechanism of adversities on fertility as a result of BPA exposure. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
69.
70.
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