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   83241篇
  免费   5689篇
  国内免费   2252篇
耳鼻咽喉   3093篇
儿科学   921篇
妇产科学   1521篇
基础医学   2352篇
口腔科学   3138篇
临床医学   7776篇
内科学   7178篇
皮肤病学   701篇
神经病学   2845篇
特种医学   1777篇
外国民族医学   20篇
外科学   29963篇
综合类   11547篇
现状与发展   6篇
一般理论   2篇
预防医学   2879篇
眼科学   4566篇
药学   3474篇
  170篇
中国医学   1639篇
肿瘤学   5614篇
  2024年   195篇
  2023年   2170篇
  2022年   2672篇
  2021年   4427篇
  2020年   4385篇
  2019年   3711篇
  2018年   3580篇
  2017年   3164篇
  2016年   3170篇
  2015年   3244篇
  2014年   6502篇
  2013年   6011篇
  2012年   4988篇
  2011年   5166篇
  2010年   4192篇
  2009年   3886篇
  2008年   3656篇
  2007年   3632篇
  2006年   3202篇
  2005年   2769篇
  2004年   2440篇
  2003年   2014篇
  2002年   1571篇
  2001年   1470篇
  2000年   1243篇
  1999年   1171篇
  1998年   933篇
  1997年   888篇
  1996年   676篇
  1995年   558篇
  1994年   491篇
  1993年   404篇
  1992年   332篇
  1991年   315篇
  1990年   210篇
  1989年   214篇
  1988年   207篇
  1987年   211篇
  1986年   173篇
  1985年   181篇
  1984年   165篇
  1983年   105篇
  1982年   115篇
  1981年   98篇
  1980年   81篇
  1979年   53篇
  1978年   36篇
  1977年   37篇
  1976年   27篇
  1975年   20篇
排序方式: 共有10000条查询结果,搜索用时 33 毫秒
81.
82.
BackgroundStoma-related obstruction (SRO) is defined as small bowel obstruction occurring around the limbs of diverting ileostomy (DI). This study was aimed to investigate the incidence, risk factors, and management of SRO after laparoscopic colorectal surgery with DI creation.MethodsThis study included 155 patients who underwent laparoscopic colorectal surgery with DI creation for rectal cancer (n = 138), ulcerative colitis (UC) (n = 14), and familial adenomatous polyposis (FAP) (n = 3) between 2011 and 2019. Univariate and multivariate analyses were performed to identify the risk factors of SRO.ResultsThe incidence of SRO was 7.7% (n = 12), and it was significantly lower (P < 0.01) in patients with lower anterior resection or intersphincteric resection (4.3%) than in those with ileal-pouch anal anastomosis (IPAA) (35.2%). The multivariate analysis revealed that IPAA was independently associated with the development of SRO (P = 0.001; odds ratio, 9.4; 95% confidence interval, 2.5–35.4). Eleven of 12 patients (92%) with SRO required trans-stomal tube decompression, and 8 of those (67%) underwent early stoma closure.ConclusionIPAA was an independent risk factor of SRO in laparoscopic colorectal surgery with DI creation. Early stoma closure was needed in most cases of SRO.  相似文献   
83.
84.
The purpose of this overview was to assess different antibiotic regimens used in orthognathic surgery and to establish an evidence-based protocol so that beneficial and adverse effects can be determined. A comprehensive literature search for systematic reviews and/or meta-analyses was conducted in MEDLINE (PubMed), EMBASE, and the Cochrane Library until March 2020. Grey literature was investigated in Google Scholar, and a manual search was done of references lists. Two meta-analyses and four systematic reviews met the inclusion criteria. The AMSTAR-2-tool was used to ascertain the potential risk of bias in the included studies, which presented moderate to high methodological quality. Lower infection rates were associated with long-term therapies of penicillin, cefazolin-cephalexin, and amoxicillin-clavulanic-acid, with rates varying from 0% - 3.13%. Higher rates were reported in placebo groups (52.6%) and short-term penicillin therapy (60%). Side effects were reported with cefazolin, clindamycin, and penicillin therapies, including nausea, pain, swelling, headache, vomiting, and skin rash. Evidence suggests that long-term antibiotics can reduce the risk of a surgical site infection (SSI) in orthognathic surgery, but there is uncertainty regarding the effects of one dose of antibiotics preoperatively versus short-term antibiotics. In the same way, intravenous penicillin, cefazolin, clindamycin, and amoxicillin-clavulanic acid kept the infection rates associated with bimaxillary procedures under 3.5%.  相似文献   
85.
IntroductionTranssphenoidal surgical removal is the preferred treatment of most pituitary adenomas. Postoperative cerebrospinal fluid (CSF) leakage is the leading cause of morbidity after this procedure, with an incidence rate that varies from 0,5-15% in the main published series.ObjectivesThe primary objective of this study was to establish the incidence of postoperative CSF leakage in a sample of surgeries performed at the University Hospital of La Ribera by the same surgical team. The secondary objectives were to: ascertain the distinctive features between patients with and without postoperative CSF leakage, identify risk factors for their development, evaluate the relationship between the surgical technique for closing the sella turcica and the onset of postoperative CSF leakage and evaluate different treatment regimens for this complication.MethodsThe data of 302 consecutive transsphenoidal surgical procedures for pituitary adenoma removal which were performed between 1999 and 2017 were retrospectively reviewed.Results and conclusionsThe incidence of postoperative CSF leakage in our series was 2,3% (in accordance with similar published studies). It was possible to correlate intraoperative CSF leakage with two variables: pituitary macroadenoma and tumors with suprasellar extension (P < .005). This correlation did not exist for postoperative CSF leakage. We found a statistically significant correlation between intraoperative and postoperative CSF leakage (P < .005). Due to the low incidence of postoperative CSF leakage in our series, it was not possible to identify risk factors for its development.  相似文献   
86.
《Clinical neurophysiology》2019,130(1):128-137
ObjectiveHigh frequency oscillations (HFO) between 80–500 Hz are markers of epileptic areas in intracranial and maybe also scalp EEG. We investigate simultaneous recordings of scalp and intracranial EEG and hypothesize that scalp HFOs provide important additional clinical information in the presurgical setting.MethodsSpikes and HFOs were visually identified in all intracranial scalp EEG channels. Analysis of correlation of event location between intracranial and scalp EEG as well as relationship between events and the SOZ and zone of surgical removal was performed.Results24 patients could be included, 23 showed spikes and 19 HFOs on scalp recordings. In 15/19 patients highest scalp HFO rate was located over the implantation side, with 13 patients having the highest scalp and intracranial HFO rate over the same region. 17 patients underwent surgery, 7 became seizure free. Patients with poor post-operative outcome showed significantly more regions with HFO than those with seizure free outcome.ConclusionsScalp HFOs are mostly located over the SOZ. Widespread scalp HFOs are indicative of a larger epileptic network and associated with poor postsurgical outcome.SignificanceAnalysis of scalp HFO add clinically important information about the extent of epileptic areas during presurgical simultaneous scalp and intracranial EEG recordings.  相似文献   
87.
IntroductionThe aims of this study were to analyze the pathological response, and survival outcomes of adenocarcinoma/adenosquamous (AC/ASC) versus squamous cell carcinoma (SCC) in patients with locally advanced cervical cancer (LACC) managed by chemoradiotherapy followed by radical surgery.MethodsRetrospective, multicenter, observational study, including patients with SCC and AC/ACS LACC patients treated with preoperative CT/RT followed by tailored radical surgery (RS) between 06/2002 and 05/2017. Clinical-pathological characteristics were compared between patients with SCC versus AC/ASC. A 1:3 ratio propensity score (PS) matching was applied to remove the variables imbalance between the two groups.ResultsAfter PS, 320 patients were included, of which 240 (75.0%) in the SCC group, and 80 (25.0%) in the AC/ASC group. Clinico-pathological and surgical baseline characteristics were balanced between the two study groups. Percentage of pathologic complete response was 47.5% in SCC patients versus 22.4% of AC/ASC ones (p < 0.001). With a median follow-up of 51 months (range:1–199), there were 54/240 (22.5%) recurrences in SCC versus 28/80 (35.0%) in AC/ASC patients (p = 0.027). AC/ASC patients experienced worse disease free (DFS), and overall survival (OS) compared to SCC patients (p = 0.019, and p = 0.048, respectively). In multivariate analysis, AC/ACS histotype, and FIGO stage were associated with worse DFS and OS.ConclusionIn LACC patients treated with CT/RT followed by RS, AC/ASC histology was associated with lower pathological complete response to CT/RT, and higher risk of recurrence and death compared with SCC patients. This highlights the need for specific therapeutic strategies based on molecular characterization to identify targets and develop novel treatments.  相似文献   
88.
Our aim was to evaluate the long-term skeletal stability of the mandible in 21 patients after orthognathic surgery with physiological positioning. The measurement points SNB, B point (X, Y), Pog (X, Y), and the angle of the ramus were measured on cephalometric photographs to assess skeletal stability preoperatively, immediately after operation, and one and two years postoperatively. In addition, we evaluated the clinical symptoms of disorders of the temporomandibular joint (TMJ). The analysis of the cephalometric photographs showed that SNB, B point X, and Pog X showed no significant differences among the postoperative time points. On the other hand, B point Y and Pog Y showed no significant differences throughout the study period. We compared the angle of the ramus before operation and two years postoperatively, and no significant difference was found. In addition, no cases showed any pathological symptoms of disorders of the TMJ two years postoperatively. The long-term stability after orthognathic surgery with physiological positioning was confirmed, and it seems to be a reliable orthognathic treatment in patients with mandibular prognathism.  相似文献   
89.

Aims

To examine the influence of pre-existing psychiatric disorder on the choice of treatment in patients with gynaecological cancer.

Materials and methods

The analyses were based on all patients who underwent surgical treatment for endometrial, ovarian or cervical cancer who were registered in the Danish Gynecological Cancer Database in the years 2007–2014 (3059 patients with ovarian cancer, 5100 patients with endometrial cancer and 1150 with cervical cancer). Logistic regression model and Cox regression model, adjusted for relevant confounders, were used to estimate the effect of pre-existing psychiatric disorder on the course of cancer treatment. Our outcomes were (i) presurgical oncological treatment, (ii) macroradical surgery for patients with ovarian cancer, (iii) radiation/chemotherapy within 30 days and 100 days after surgery and (iv) time from surgery to first oncological treatment.

Results

In the group of patients with ovarian cancer, more patients with a psychiatric disorder received macroradical surgery versus patients without a psychiatric disorder, corresponding to an adjusted odds ratio of 1.24 (95% confidence interval 0.62–2.41) and the chance for having oncological treatment within 100 days was odds ratio = 1.26 (95% confidence interval 0.77–2.10). As for patients with endometrial cancer, all outcome estimates were close to unity. The adjusted odds ratio for oncological treatment within 30 days after surgery in patients with cervical cancer with a history of psychiatric disorder was 0.20 (95% confidence interval 0.03–1.54).

Conclusions

We did not find any significant differences in the treatment of ovarian and endometrial cancer in patients with pre-existing psychiatric diagnoses. When it comes to oncological treatment, we suggest that increased attention should be paid to patients with cervical cancer having a pre-existing psychiatric diagnosis.  相似文献   
90.
ObjectiveThis study evaluates the impact of a novel model of care called Geriatric Comanagement of Older Vascular surgery inpatients on clinical outcomes.Design, Setting, and ParticipantsA pre-post study of geriatric comanagement, comparing prospectively recruited preintervention (February–October 2019) and prospectively recruited postintervention (January–December 2020) cohorts. Consecutively admitted vascular surgery patients age ≥65 years at a tertiary academic hospital in Concord and with an expected length of stay (LOS) greater than 2 days were recruited.InterventionA comanagement model where a geriatrician was embedded within the vascular surgery team and delivered proactive comprehensive geriatric assessment based interventions.MethodsPrimary outcomes of incidence of hospital-acquired geriatric syndromes, delirium, and LOS were compared between groups using univariable and multivariable logistic regression analyses. Prespecified subgroup analysis was performed by frailty status.ResultsThere were 150 patients in the preintervention group and 152 patients in the postintervention group. The postintervention group were more frail [66 (43.4%) vs 45 (30.0%)], urgently admitted [72 (47.4%) vs 56 (37.3%)], and nonoperatively managed [52 (34.2%) vs 33 (22.0%)]. These differences were attributed to the coronavirus disease 2019 pandemic during the postintervention phase. The postintervention group had fewer hospital-acquired geriatric syndromes [74 (48.7%) vs 97 (64.7%); P = .005] and reduced incident delirium [5 (3.3%) vs 15 (10.0%); P = .02], in unadjusted and adjusted analyses. Cardiac [8 (5.3%) vs 30 (20.0%); P < .001] and infective complications [4 (2.6%) vs 12 (8.0%); P = .04] were also fewer. LOS was unchanged. Frail patients in the postintervention group experienced significantly fewer geriatric syndromes including delirium.Conclusions and ImplicationsThis is the first prospective study of inpatient geriatric comanagement for older vascular surgery patients. Reductions in hospital-acquired geriatric syndromes including delirium, and cardiac and infective complications were observed after implementing geriatric comanagement. These benefits were also demonstrated in the frail subgroup.  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