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   15403篇
  免费   1707篇
  国内免费   797篇
耳鼻咽喉   39篇
儿科学   56篇
妇产科学   154篇
基础医学   1204篇
口腔科学   77篇
临床医学   1365篇
内科学   1016篇
皮肤病学   92篇
神经病学   613篇
特种医学   266篇
外国民族医学   3篇
外科学   1097篇
综合类   3139篇
现状与发展   2篇
预防医学   719篇
眼科学   113篇
药学   1912篇
  20篇
中国医学   5409篇
肿瘤学   611篇
  2024年   84篇
  2023年   562篇
  2022年   1147篇
  2021年   1224篇
  2020年   1336篇
  2019年   680篇
  2018年   573篇
  2017年   660篇
  2016年   687篇
  2015年   794篇
  2014年   1258篇
  2013年   1292篇
  2012年   1754篇
  2011年   1593篇
  2010年   1030篇
  2009年   737篇
  2008年   425篇
  2007年   473篇
  2006年   356篇
  2005年   232篇
  2004年   159篇
  2003年   131篇
  2002年   113篇
  2001年   94篇
  2000年   74篇
  1999年   76篇
  1998年   53篇
  1997年   44篇
  1996年   64篇
  1995年   31篇
  1994年   24篇
  1993年   28篇
  1992年   10篇
  1991年   18篇
  1990年   13篇
  1989年   10篇
  1988年   22篇
  1987年   22篇
  1986年   20篇
  1985年   4篇
排序方式: 共有10000条查询结果,搜索用时 312 毫秒
91.
92.
BACKGROUND CONTEXTSurgical correction strategies for adult spinal deformity (ASD) relies heavily on radiographic alignment goals, however, there is often debate regarding degree of correction and how static alignment translates to physical ability in daily life. Kinematic analysis has the potential to improve the concept of ideal spinal alignment by providing clinically meaningful estimates of dynamic changes in spinal alignment during activities of daily life.PURPOSEEstimate representative dynamic ranges of spinal alignment during gait among ASD patients using 3D motion tracking; compare dynamic alignment between mild and severe deformity patients and to healthy adults.STUDY DESIGN/SETTINGRetrospective review at a single institution.PATIENT SAMPLEFifty-two ASD patients and 46 healthy adults.OUTCOME MEASURESRadiographic alignment, kinematic spine motion, spatiotemporal gait measures, patient reported outcomes (VAS pain, ODI, SRS-22r).METHODSSpinal alignment was assessed radiographically and during standing and overground walking tests. Dynamic alignment was initialized by linking radiographic alignment to kinematic alignment during standing and at initial heel contact during gait. Dynamic changes in maximums and minimums during gait were made relative to initial heel contact for each gait cycle. Total range-of-motion (RoM) was measured for both ASD and healthy subjects. Dynamic alignment measures included coronal and sagittal vertical axes (CVA, SVA), T1 pelvic angle (TPA), lumbar lordosis (LL), and pelvic tilt (PT). ASD patient's deformities were classified as either Mild or Severe based on the SRS-Schwab ASD classification.RESULTSSevere ASD patients had significantly larger dynamic maximum and minimums for SVA, TPA, LL, and PT (all p<.05) compared with Mild ASD patients. ASD patients exhibited little difference in dynamic alignment compared with healthy subjects. Only PT had a significant difference in dynamic RoM compared with healthy (p<.001).CONCLUSIONSMild and Severe ASD patients exhibited similar global dynamic alignment measures during gait and had comparable RoM to healthy subjects except with greater PT and reduced spatiotemporal performance which may be key compensatory mechanisms for dynamic stabilization.  相似文献   
93.
Background ContextPrevious studies have reported conflicting results for the relationships between anthropometric adiposity indexes and bone mineral density, based on dual-energy X-ray absorptiometry (DXA). However, few studies were published based on quantitative computed tomography (QCT), especially for Chinese population.PurposeTo evaluate the associations of spine bone mineral density (BMD) with body mass index (BMI), waist circumstance (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and a body shape index (ABSI) using QCT.Study Design/SettingA Cross-sectional study.Patient SampleAround 3,457 participants in multiple communities across 7 administrative regions of China.Outcome MeasuresSpine BMD was measured using QCT, and the classification of osteoporosis was defined as follows: 1) osteoporosis if BMD <80mg/cm3, 2) osteopenia if BMD 80–119 mg/cm3, and 3) normal bone mass if BMD≥120 mg/cm3.MethodsThis study was conducted using convenient sampling between 2013 and 2017. Multivariable linear regression model and logistic regression models were used for the associations of continuous and categorical BMD, respectively.ResultsAround 3,405 participants were included in the final analyses, including 1,272 males and 2,133 females, with spine BMD of 111.00±35.47 mg/cm3 and 99.38±40.60 mg/cm3, respectively. Spine BMD decreased significantly with the increase of ABSI in females (adjusted β, ?5.74; 95% confidence interval [CI], ?8.50 to ?2.98), and this trend also was kept in females aged at less than 60 years (adjusted β, ?14.54; 95% CI, ?20.40 to ?8.68), and females with age ≥60 years (adjusted β, ?7.59; 95% CI, ?10.91 to ?4.28). However, this inverse association was observed only in males with age ≥ 60 years (adjusted β, ?5.19; 95% CI, ?10.08 to ?0.29). Except ABSI, negative associations of Spine BMD with WC (adjusted β, ?0.46; 95% CI, ?0.77 to ?0.15), WHR (adjusted β, ?6.25; 95% CI, ?10.63 to ?1.86), WHtR (adjusted β, ?6.80; 95% CI, ?11.63 to ?1.97) were shown in females aged at <60 years, and positive association with BMI in males with age ≥60 years (adjusted β, 0.92; 95% CI, 0.29–1.55).ConclusionsABSI had more remarkable association with spine BMD, compared with the other four indexes.  相似文献   
94.
95.
目的探讨腹腔镜辅助食管胃吻合肌瓣成形术(Kamikawa吻合)在治疗肿瘤最大径>5 cm的食管胃结合部(EGJ)平滑肌瘤或胃肠间质瘤近端胃切除术后消化道重建的安全性及可行性。方法采用描述性病例系列研究方法,回顾性分析广东省中医院胃肠外科2017年9月至2019年3月期间,收治并施行腹腔镜辅助近端胃切除术和Kamikawa吻合的EGJ平滑肌瘤和胃肠间质瘤病例资料。肿瘤均侵犯贲门齿状线,且最大径>5 cm;排除需急诊手术和合并有严重心肺疾病患者后,共4例患者纳入本研究,男性3例,女性1例,年龄29-49岁。患者接受腹腔镜辅助近端胃切除术后,把残胃提出腹腔外,距残胃前壁近端3-4 cm处亚甲蓝标记"H"形,并沿"H"形切开胃壁浆肌层,沿纵行切开线向两侧分离黏膜下层和肌层之间的间隙,制作浆肌瓣;将残胃放回腹腔,腹腔镜下将"H"形上边与食管后壁距断端4-5 cm处间断缝合4针;切开食管残端,在"H"形的下边切开黏膜下层和黏膜层,进入胃腔;腹腔镜下将食管断端后壁与残胃黏膜层和黏膜下层连续缝合,食管断端前壁与残胃全层连续缝合,将胃前壁浆肌瓣缝合包埋食管,完成消化道重建。观察患者术中并发症和术后反流性食管炎和吻合口相关并发症的发生率。结果 4例患者均顺利完成手术,无中转开腹。手术中位时间为239(192-261)min,Kamikawa吻合中位时间为149(102-163)min,术中中位出血量为35(20-200)ml。4例患者均术后第1天拔除腹腔引流管和胃管,并恢复流质饮食,术后住院中位时间为6(6-8)d。术后病理提示,3例平滑肌瘤,1例胃肠间质瘤。术后无吻合口漏及狭窄等并发症,未观察到反流症状。术后中位随访时间22(11-29)个月,4例患者复查胃镜均未见反流性食管炎。结论对于>5 cm的EGJ平滑肌瘤或胃肠间质瘤,近端胃切除术后应用腹腔镜辅助Kamikawa吻合进行消化道重建,安全可行。  相似文献   
96.
目的 了解中国农村地区现在吸烟者戒烟意愿,探索其影响因素,为控烟工作提供参考。方法 本研究数据来源于2018年中国慢性病及危险因素监测,采用多阶段分层整群抽样的方法抽取184 509名≥18岁居民,其中10 241名农村现在吸烟者纳入研究。采用χ2/F检验对戒烟意愿与人口学信息、烟草使用情况、烟草相关危害知识的认知、慢性病患病情况等因素进行单因素分析,多因素分析采用非条件多因素logistic回归分析。结果 3 453名(37.46%)考虑在未来12个月内戒烟。logistic回归分析显示,偶尔吸烟者的戒烟意愿高于每天吸烟者(OR=0.693,95%CI:0.494~0.971),每天吸烟量<1包者的戒烟意愿高于≥1包者(OR=0.628,95%CI:0.511~0.771),12个月内有戒烟经历者的戒烟意愿高于12个月内未戒过烟的现在吸烟者(OR=0.438,95%CI:0.357~0.537),烟草危害认知程度高者戒烟意愿更高(OR=1.056,95%CI:1.028~1.086),差异均有统计学意义(P<0.05)。结论 中国农村地区现在吸烟者戒烟意愿与吸烟状况、吸烟量、戒烟情况、烟草危害认知有关。建议加强对农村地区的健康教育宣传,提供简短的戒烟干预,提高农村现在吸烟者的戒烟意愿。  相似文献   
97.
98.
99.
BackgroundPatients undergoing breast reduction mammoplasty for symptomatic macromastia have a significantly improved quality of life postoperatively. However, there are no data that examine the effect of reduction mammoplasty on quality of life as a function of the weight of tissue removed. Because the process by which insurance providers consider patients’ candidacy for this breast reduction mammoplasty is most often based on the proposed weight of tissue to be removed, this gap in our understanding is particularly glaring. We therefore designed a prospective trial with the intent of investigating the correlation between breast reduction specimen weight and postoperative pain and quality of life.MethodsAfter obtaining institutional review board (IRB) approval, patients presenting for breast reduction mammoplasty at a single academic medical center between January 2016 and September 2019 were prospectively enrolled in the study. Study participants completed the Numerical Pain Rating Scale (NPRS), the short-form McGill Pain Questionnaire (SF-MPQ), and the BREAST-Q at set time points (preoperatively, 1 week/1 month/3 months/6 months postoperatively). Patients were divided into three cohorts based on breast reduction specimen weights: small (<500 g reduction), intermediate (500–1000 g reduction), and large (>1000 g reduction). The surveys were then analyzed while controlling for demographic factors and complications.ResultsA total of 85 women were enrolled in the study and completed pre- and postoperative surveys (small reduction n = 21 (25%), intermediate n = 45 (53%), and large n = 19 (22%)). Regardless of reduction specimen weight, patients reported decreased overall pain and increased satisfaction with their breasts, as well as improved psychosocial, sexual, and physical well-being at each postoperative visit. Preoperative SF-MPQ pain scores were significantly lower in the small specimen weight group compared with either the intermediate or the large group (p = 0.001). Postoperatively, both the intermediate and large groups reported significant improvement in pain at each time point. The small specimen weight group did not report significant pain improvement until 3 months postoperatively.ConclusionsPatients undergoing breast reduction mammoplasty experience decreased pain and improved quality of life regardless of reduction specimen weight. Improvement in these parameters manifests as early as 1 week postoperatively and maintained at 3 months postoperatively. These data suggest that many patients who are denied coverage for reduction mammoplasty on the basis of low projected reduction specimen weight would derive significant benefit from the procedure.  相似文献   
100.
Introduction and objectiveThe objective of the study was to evaluate the functional and cosmetic outcome of single-stage modified partial penile disassembly repair in isolated male epispadias.Materials and methodsA retrospective analysis of 15 cases of primary epispadias repair, from June 2015 to December 2018, was performed. Patients were classified by the type of epispadias, urinary incontinence, chordee, and rotation.Surgical techniquePenile degloving with the mobilization of the urethral plate from the ventral to the dorsal aspect with the preservation of blood supply at both ends, distally up to the level of mid-glans and proximally up to the pubic symphysis is done. Tubularization of urethral plate followed by spongioplasty, corporoplasty with medial rotation of corporeal bodies, and glanuloplasty with meatoplasty was done to bring the meatus ventrally. The skin cover is done by the rotation of the ventral flaps and the z-plasty whenever required.ResultsAge of the patients varied from 4 months to 21 years with a mean of 11 years. Thirteen patients had excellent cosmetic outcome while two patients had minimal residual chordee but did not require any surgery in a follow-up. Five patients with partial incontinence in the study group achieved continence after surgery. None of the patients developed complications such as fistula or stricture. All five male patients in the post-pubertal group reported normal erections and successful ejaculations after the surgery. Follow-up ranged from 3 months to 18 months.ConclusionsModified partial penile disassembly incorporates all the benefits of Cantwell Ransley repair and needs less extensive dissection than total penile disassembly. Both functional and cosmetic results are good with a low complication rate.  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