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   5672篇
  免费   467篇
  国内免费   139篇
耳鼻咽喉   60篇
儿科学   105篇
妇产科学   118篇
基础医学   668篇
口腔科学   143篇
临床医学   601篇
内科学   1313篇
皮肤病学   57篇
神经病学   337篇
特种医学   133篇
外科学   812篇
综合类   285篇
一般理论   7篇
预防医学   365篇
眼科学   110篇
药学   480篇
  1篇
中国医学   146篇
肿瘤学   537篇
  2023年   39篇
  2022年   78篇
  2021年   151篇
  2020年   96篇
  2019年   134篇
  2018年   146篇
  2017年   113篇
  2016年   154篇
  2015年   189篇
  2014年   239篇
  2013年   274篇
  2012年   402篇
  2011年   439篇
  2010年   278篇
  2009年   244篇
  2008年   335篇
  2007年   376篇
  2006年   298篇
  2005年   339篇
  2004年   301篇
  2003年   275篇
  2002年   240篇
  2001年   194篇
  2000年   162篇
  1999年   108篇
  1998年   44篇
  1997年   45篇
  1996年   35篇
  1995年   28篇
  1994年   27篇
  1993年   19篇
  1992年   50篇
  1991年   61篇
  1990年   50篇
  1989年   33篇
  1988年   26篇
  1987年   16篇
  1986年   30篇
  1985年   28篇
  1984年   19篇
  1983年   18篇
  1982年   8篇
  1981年   8篇
  1980年   13篇
  1979年   18篇
  1978年   20篇
  1977年   11篇
  1976年   9篇
  1974年   11篇
  1973年   8篇
排序方式: 共有6278条查询结果,搜索用时 15 毫秒
51.
目的探讨腹主动脉瘤腔内修复术中特殊远端锚定区的处理方法以及并发症。方法自1997年5月至2006年12月在150例包括髂总动脉瘤、髂内动脉瘤、髂动脉狭窄、严重成角等特殊远端锚定区的腹主动脉瘤腔内修复术中,根据情况选择不同的处理方式,术后观察内漏、缺血并发症、髂动脉瘤形态以及旁路血管的通畅性。结果围手术期死亡率4%(6/150),总死亡率42.5%(51/120)。6例原发性远端I型内漏,5例自愈,1例转化为持续性内漏;3例髂内动脉返流引起的Ⅱ型内漏随访中均自愈。7例单臂支架型血管,股股旁路手术2年通畅率为86%;4例髂内动脉旁路手术2年通畅率为100%。11例栓塞单侧髂内动脉出现臀肌缺血症状,平均症状消失时间42 d(5-90 d)。结论结合传统外科技术以及腔内技术,并选择合适的产品处理腹主动脉瘤特殊远端锚定区可取得满意疗效。中远期结果仍需观察。  相似文献   
52.
Laparoscopic versus open appendectomy for complicated appendicitis   总被引:2,自引:0,他引:2  
BACKGROUND: Laparoscopic appendectomy has been widely practiced for uncomplicated appendicitis; various reports demonstrated its merits in assisting diagnosis, reducing postoperative pain, analgesic requirement, and incidence of wound infection. The role of laparoscopy in management of complicated appendicitis, ie, gangrenous, perforated appendicitis and appendiceal abscess, remains undefined. Currently, the choice of operative approach is mostly at the surgeons' discretion. A retrospective study was conducted in our institution to review the feasibility, safety, and efficacy of laparoscopic appendectomy for patients with complicated appendicitis. STUDY DESIGN: From January 1999 to January 2004, records of patients older than 14 years of age with diagnosis of appendicitis were retrieved from computer database for analysis. All patients underwent diagnostic laparoscopy to confirm diagnosis of complicated appendicitis, and patients subsequently underwent either laparoscopic or open appendectomies. Patients' demographics data and perioperative outcomes from the two groups were compared. RESULTS: During the study period, 1,133 patients with acute appendicitis underwent operations in our institution. Two hundred forty-four patients (21.5%) with complicated appendicitis were identified by laparoscopy, of which 175 underwent laparoscopic appendectomy (LA) and 69 had open appendectomy (OA). Both groups of patients were comparable in demographics. Mean operative time was 55 minutes for LA group and 70 minutes for the OA group (p<0.001). Mean hospital stay was 5 days and 6 days for LA and OA group respectively (p<0.001). There was one conversion patient (0.6%) in the LA group who suffered from wound infection, and there were seven (10%) wound infections in the OA group (p=0.001). There were 10 cases (5.7%) of intraabdominal collection in the LA group and 3 (4.3%) in the OA group (p=0.473). There was no mortality in the current series. CONCLUSIONS: Laparoscopic appendectomy for complicated appendicitis is feasible and safe. It is associated with a significantly shorter operative time, lower incidence of wound infection, and reduced length of hospital stay when compared with patients who had open appendectomy.  相似文献   
53.
肝癌合并下腔静脉癌栓的治疗仍是医学难题,一直被视为手术禁忌证.患者主要接受非手术治疗或放弃治疗,其生存率较低.近年来随着医学的进步,手术治疗肝癌合并下腔静脉癌栓的成功率逐年增高.201 1年5月哈尔滨医科大学附属第二医院为1例肝癌合并下腔静脉癌栓患者行肝脏Ⅴ、Ⅶ、Ⅷ段切除+下腔静脉癌栓取出术.术前CT检查示肝Ⅴ、Ⅶ、Ⅷ段占位性病变,下腔静脉内癌栓充盈,三维重建测算左半肝体积489 cm^3,低于最小存活肝脏体积.为了最大限度保留剩余肝脏,拟行保留肝Ⅵ段的右半肝切除术,于全肝血流阻断下腔静脉癌栓取出术.患者术后恢复良好,术后18个月复查未见明显复发转移症状.  相似文献   
54.
目的 评价和比较经腹腔镜与开腹根治性手术治疗肝脏囊型包虫病的临床疗效.方法 回顾性分析2006年5月至2013年1月收住并接受根治性手术治疗的肝脏囊型包虫病患者的临床资料,并对手术时间、术中出血量、中转开腹率、平均术后住院时间、术后并发症进行统计学分析.结果 本研究共纳入153例患者,其中41例行经腹腔镜手术(腹腔镜组)、112例行传统开腹手术(开腹组).腹腔镜组平均手术时间较开腹手术短,但差异无统计学意义(t=1.97,P>0.05).腹腔镜组5例患者行中转开腹手术,中转开腹率为12.2%(5/41).2组术中出血量比较差异无统计学意义(t=2.00,P>0.05).腹腔镜组平均术后住院时间为3~8 d,而开腹组为4~14d,差异有统计学意义(t=1.99,P<0.05).腹腔镜组并发症发生率为4.9%(2/41)、开腹组并发症发生率16.0%(18/112),差异有统计学意义(x2=3.92,P<0.05).结论 腹腔镜肝包虫根治性手术治疗较传统开腹肝脏囊型包虫病手术治疗具有术后住院时间短,并发症少,恢复快,复发率低的特点,在严格选择患者的条件下是安全和可行的.  相似文献   
55.
目的探讨应用个案管理模式对提高乳腺癌患者治疗后首次复查率的影响。方法回顾选择2015年1月至2015年3月,在我科新确诊为乳腺癌,接受常规医疗护理治疗的64例患者设为常规医疗护理组;选择2016年1月至2016年3月,在我科接受常规医疗护理治疗并同时应用个案管理模式的81例乳腺癌患者设为个案管理模式组,两组均在完成手术(或结束辅助治疗后)被告知三个月后返院首次复查,比较个案管理模式应用前后患者的首次复查率。结果常规医疗护理组的首次复查率为65.63%,个案管理模式组的首次复查率为87.65%,提高了22.02%,两组患者的复查率差异有统计学意义(P0.05),个案管理模式组优于常规医疗护理组。结论个案管理模式的应用能提高乳腺癌患者治疗后的首次复查率。  相似文献   
56.

Summary

All-cause mortality risk persisted for 5 years after hip fractures in both men and women. There may be gender-specific differences in effect and duration of excess risk for cause-specific mortality after hip fracture.

Introduction

To determine all-cause and cause-specific mortality risk in the first 5 years after hip fracture in an Asian Chinese population.

Methods

The Singapore Chinese Health Study is a population-based cohort of 63,257 middle-aged and elderly Chinese men and women in Singapore recruited between 1993 and 1998. This cohort was followed up for hip fracture and death via linkage with nationwide hospital discharge database and death registry. As of 31 December 2008, we identified 1,166 hip fracture cases and matched five non-fracture cohort subjects by age and gender for each fracture case. Cox proportional hazards and competing risks regression models with hip fracture as a time-dependent covariate were used to determine all-cause and cause-specific mortality risk, respectively.

Results

Increase in all-cause mortality risk persisted till 5 years after hip fracture (adjusted hazard ratio, aHR = 1.58 [95 % CI, 1.35–1.86] for females and aHR = 1.64 [95 % CI, 1.30–2.06] for males). Men had higher mortality risk after hip fracture than women for deaths from stroke and cancer up to 1 year post-fracture but women with hip fracture had higher coronary artery mortality risk than men for 5 years post-fracture. Men had higher risk of death from pneumonia while women had increased risk of death from urinary tract infections. There was no difference in mortality risk by types of hip fracture surgery.

Conclusions

All-cause mortality risk persisted for 5 years after hip fractures in men and women. There are gender-specific differences in effect size and duration of excess mortality risk from hip fractures between specific causes of death.  相似文献   
57.
Introduction Superior cut-out of a lag screw remains a serious complication in the treatment of intertrochanteric fractures. It is related to the stability of fracture reduction. We describe the application of a trochanter supporting plate (TSP) to restore the fracture stability after early cut-out of a lag screw in unstable intertrochanteric fractures.Materials and methods A total of 11 consecutive patients with superior cut-out of the lag screw of a dynamic hip screw (DHS) or a gamma nail in an unstable intertrochanteric fracture occurring within 6 months after surgery were included in the present study. They underwent repeat surgery for placement of a DHS and a laterally mounted TSP of our design. All patients were monitored for at least 6 months (median 15 months; range 6–28 months).Results There was no repeated cut-out of a lag screw, and 10 patients (91%) achieved bony union within 5 months. At the last follow-up, all patients could walk with or without aids.Conclusion It reveals that a TSP, as an adjuvant to a lag screw placed inferiorly, is an easy and safe solution for the treatment of early cut-out of a lag screw in unstable intertrochanteric fractures.  相似文献   
58.
59.

Background

Although perineural invasion (PNI) has been a poor prognostic factor for head and neck cancers, few studies have focused on oral squamous cell carcinoma (OSCC). The independent significance of PNI in early T1-2 OSCC and the benefit of treatment modification based on PNI status have not been assessed. This study investigated the role of PNI in T1-2 OSCC patients, with focus on the controversial issues of neck management and postoperative adjuvant therapy.

Methods

PNI status was re-reviewed under hematoxylin and eosin staining in tumors of 307 consecutive T1-2 OSCC patients. Oncologic and survival outcomes were analyzed by univariate and multivariate analyses.

Results

PNI was identified in 84 (27.4%) patients, correlating with several established poor prognostic factors. In multivariate analysis, PNI remained an independent predictor for neck metastasis, neck recurrence, and a worse 5-year disease-specific survival. Elective neck dissection contributed to a significantly better 5-year disease-specific survival only in cN0 patients with PNI-positive tumors (P?=?0.0071) but not in those with PNI-negative tumors (P?=?0.3566). In low-risk patients who were treated by surgery alone, including neck dissection, the 5-year disease-specific survival rates were almost the same in those with PNI-positive tumors and those with PNI-negative tumors (92.0 vs. 92.9%; P?=?0.9104).

Conclusions

Elective neck dissection is indicated for cN0 patients with PNI-positive tumors for the efficacy of improving disease-specific survival as well as neck control. However, low-risk PNI-positive patients who undergo neck dissection do not need postoperative adjuvant therapy, because the residual risk from PNI is minimal.  相似文献   
60.
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