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   3211篇
  免费   175篇
  国内免费   8篇
耳鼻咽喉   30篇
儿科学   122篇
妇产科学   54篇
基础医学   345篇
口腔科学   74篇
临床医学   249篇
内科学   714篇
皮肤病学   53篇
神经病学   123篇
特种医学   455篇
外科学   454篇
综合类   66篇
预防医学   165篇
眼科学   46篇
药学   282篇
  1篇
中国医学   22篇
肿瘤学   139篇
  2023年   21篇
  2022年   54篇
  2021年   83篇
  2020年   38篇
  2019年   53篇
  2018年   63篇
  2017年   38篇
  2016年   52篇
  2015年   53篇
  2014年   100篇
  2013年   123篇
  2012年   130篇
  2011年   142篇
  2010年   91篇
  2009年   109篇
  2008年   118篇
  2007年   141篇
  2006年   121篇
  2005年   116篇
  2004年   91篇
  2003年   83篇
  2002年   58篇
  2001年   53篇
  2000年   56篇
  1999年   62篇
  1998年   88篇
  1997年   93篇
  1996年   85篇
  1995年   72篇
  1994年   50篇
  1993年   67篇
  1992年   35篇
  1991年   41篇
  1990年   48篇
  1989年   79篇
  1988年   70篇
  1987年   59篇
  1986年   69篇
  1985年   86篇
  1984年   55篇
  1983年   45篇
  1982年   32篇
  1981年   42篇
  1980年   42篇
  1979年   23篇
  1978年   28篇
  1977年   32篇
  1976年   30篇
  1975年   29篇
  1974年   11篇
排序方式: 共有3394条查询结果,搜索用时 15 毫秒
991.
992.
Subintimal angioplasty is a safe, effective, but nondurable procedure in treating long superficial femoral artery occlusions in patients with severe lower limb ischemia. The authors report a case of acute thrombosis that presented 16 weeks after subintimal angioplasty. The ;;Trellis' percutaneous thrombolytic infusion system permitted a controlled site-specific infusion of recombinant tissue-type plasminogen activator (rtPA). The unique design of the ;;Trellis' allowed complete aspiration of thrombus and avoiding regional and systemic thrombolytic side effects. The ;;Trellis' system is effective in percutaneous management of thrombotic lesions; however, intimal dissection may need to be addressed.  相似文献   
993.
BACKGROUND: Multiple drug immunosuppression has allowed the near elimination of rejection, but without commensurate improvements in longterm graft survival and at the cost of quality of life. We have suggested that transplantation outcomes can be improved by modifying the timing and dosage of immunosuppression to facilitate natural mechanisms of alloengraftment and acquired tolerance. STUDY DESIGN: Two therapeutic principles were applied for kidney transplantation: pretransplant recipient conditioning with antilymphoid antibody preparations (Thymoglobulin [Sangstat] or Campath [ILEX Pharmaceuticals]), and minimal posttransplant immunosuppression with tacrolimus monotherapy including "spaced weaning" of maintenance doses when possible. The results in Thymoglobulin- (n = 101) and Campath-pretreated renal transplantation recipients (n = 90) were compared with those in 152 conventionally immunosuppressed recipients in the immediately preceding era. RESULTS: Spaced weaning was attempted in more than 90% of the kidney transplant recipients after pretreatment with both lymphoid-depleting agents, and is currently in effect in two-thirds of the survivors. Although there was a much higher rate of acute rejection in the Thymoglobulin-pretreated recipients than in either the Campath-pretreated or historic control recipients, patient and graft survival in both lymphoid depletion groups is at least equivalent to that of historic control patients. In the Thymoglobulin-conditioned patients for whom followups are now 24 to 40 months, chronic allograft nephropathy (CAN) progressed at the same rate as in historic control patients. Selected patients on weaning developed donor-specific nonreactivity. CONCLUSIONS: After lymphoid depletion, kidney transplantation can be readily accomplished under minimal immunosuppression with less dependence on late maintenance immunosuppression and a better quality of life. Campath was the more effective agent for pretreatment. Guidelines for spaced weaning need additional refinement.  相似文献   
994.
STUDY OBJECTIVE: To quantify the prevalence of perioperative beta-blocker use and its impact on preoperative and preinduction heart rate (HR), in light of the recent publication of specific recommendations regarding perioperative beta-blocker use and desired HR. DESIGN: Retrospective observational study in patients who underwent elective and coronary artery bypass graft (CABG) surgery between January 2001 and March 2002. SETTING: Tertiary-care teaching hospital. MEASUREMENTS: Percentage of eligible patients who received beta-blockers preoperatively and the impact of non-protocol-based beta-blocker therapy on preadmission and preinduction HR were recorded. Differences were assessed with unpaired t test and chi(2) analysis; P < .05 was considered significant, with corrections for multiple comparisons. RESULTS: Of the patients who underwent vascular surgery, 9 had documented prior beta-blocker intolerance. Of the remaining 172 patients, 94.8% had indication for perioperative beta-blocker use. However, only 47.7% of the eligible patients received beta-blockers. Of the 155 CABG patients, 74.2% were taking beta-blockers preoperatively. Only 29% of vascular patients and 32% of CABG patients who were receiving beta-blockers had HR less than 60 beats per minute (bpm) at preadmission. The mean preadmission HR in vascular surgery patients was 65.2 +/- 11 and 73.2 +/- 13.8 bpm in beta-blocker and non-beta-blocker patients, respectively (P = .0001). In CABG surgery patients, preadmission HR values were 64.2 +/- 13 and 76.1 +/- 12 bpm in beta-blocker and non-beta-blocker patients, respectively (P = .001). The preinduction HR subsequently increased in the beta-blocker as well as in the non-beta-blocker groups. CONCLUSION: Only half of the patients who qualify to receive preoperative beta-blockers by current recommendations actually receive them before noncardiac surgery, and the majority of these patients have preadmission and preinduction HR less than 60 bpm. Targeting beta-blocker therapy treatment to an HR less than 60 bpm may not be readily achievable in many patients.  相似文献   
995.
Most translabyrinthine temporal bone defects are reconstructed with free abdominal fat grafts, with or without the use of hydroxyapatite cement. However, these procedures are associated with considerable morbidity at the graft donor site, with a 6 to 15% incidence of cerebrospinal fluid (CSF) leaks, and with postoperative headaches. We have developed a new technique for reconstructive cranioplasty that involves the use of hydroxyapatite cement and a pericranial/deep temporal fascia graft. This technique obviates the need for an abdominal fat graft and therefore circumvents the morbidity associated with it; it may also significantly reduce the incidence of CSF leaks and postoperative headaches. We describe the results of our use of this technique in a series of 10 patients. Based on our early findings, we believe that this technique holds great promise for reconstructive cranioplasty following translabyrinthine craniectomy.  相似文献   
996.
We report on the hemorheological profile of a 16 year old school girl in whom liver transplant was performed due to primary sclerosing cholangitis complicated by biliary stricture. This patient turned out to be of particular hemorheological interest, displaying pre-transplant grossly increased hematocrit-standardized (45%) blood viscosity due to hyperaggregation and elevated plasma viscosity, which is a reflection of elevated immunoglobulins (IgG, IgA and IgM) and alpha-2-macroglobulin. Post-transplant values of rheological parameters were within the normal range for healthy controls.  相似文献   
997.
Somatic delusional disorder is an uncommon psychiatric disorder that has been typically reported in elderly women. This article reviews the literature and describes a Saudi female patient who presented with novel somatic delusion of turabosis--the conviction that she was continually being covered by sand from sandstorms. Although the systematized delusional convictions remained unshakable, her anxiety and mood symptoms responded to a regimen of tricyclic antidepressants and her delusional beliefs resolved within eight weeks of treatment with risperidone. Sociocultural themes and therapeutic approaches to somatic delusional disorder are discussed.  相似文献   
998.
Concerns about the erroneous diagnosis of death and premature burial have been expressed from times immemorial. Patients with brain stem death have absolutely no chance of recovery. brain death is considered at par with death in most of the countries. General public in most parts of the world shows reluctance to accept this concept due to different social, cultural and religious backgrounds and state of literacy and awareness. The criteria for the diagnosis of brain death have been established which include certain pre-conditions, exclusions and tests of the brain stem function. These criteria are universally accepted. The criteria in children are somewhat different from the adults. The subject is intimately related with organ transplantation. If the patient is registered as organ donor or the family consents, organs can be harvested from brain dead patients for transplantation. Pakistan is amongst the few countries where no legislation exists to accept brain death as being at par with death of an individual, and to facilitate and regulate, cadaveric organ donation and transplantation.  相似文献   
999.
1000.
We are presenting here eight cases of advanced osteosarcoma of shoulder region involving scapula and upper humerus in children upto the age of thirteen years. All patients had complete loss of movement. Five patients underwent fore quarter amputation. Extensive amputation although a major mutilating procedure, provides patients a dramatic relief for the period that he survives.  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