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   876篇
  免费   32篇
  国内免费   12篇
耳鼻咽喉   6篇
儿科学   45篇
妇产科学   13篇
基础医学   88篇
口腔科学   9篇
临床医学   77篇
内科学   285篇
皮肤病学   10篇
神经病学   7篇
特种医学   136篇
外科学   84篇
综合类   15篇
预防医学   18篇
眼科学   3篇
药学   29篇
  1篇
中国医学   6篇
肿瘤学   88篇
  2022年   7篇
  2021年   9篇
  2020年   6篇
  2019年   4篇
  2018年   9篇
  2017年   5篇
  2016年   16篇
  2015年   13篇
  2014年   21篇
  2013年   27篇
  2012年   27篇
  2011年   36篇
  2010年   41篇
  2009年   34篇
  2008年   30篇
  2007年   33篇
  2006年   30篇
  2005年   33篇
  2004年   26篇
  2003年   25篇
  2002年   25篇
  2001年   28篇
  2000年   19篇
  1999年   19篇
  1998年   31篇
  1997年   28篇
  1996年   41篇
  1995年   38篇
  1994年   34篇
  1993年   18篇
  1992年   6篇
  1991年   11篇
  1990年   6篇
  1989年   19篇
  1988年   25篇
  1987年   19篇
  1986年   14篇
  1985年   16篇
  1984年   10篇
  1983年   8篇
  1982年   6篇
  1981年   8篇
  1980年   9篇
  1979年   4篇
  1978年   5篇
  1977年   7篇
  1976年   5篇
  1975年   4篇
  1970年   4篇
  1967年   5篇
排序方式: 共有920条查询结果,搜索用时 15 毫秒
61.
Interobserver variation in the interpretation of abdominal radiographs   总被引:2,自引:0,他引:2  
A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern.  相似文献   
62.
63.
The literature is confusing as to the need for anterior column fusion in the surgical treatment of patients with high-grade dysplastic spondylolisthesis. The current authors present an analysis of consecutive pediatric patients treated surgically for high-grade spondylolisthesis with and without anterior column structural support with emphasis on fusion rates, segmental kyphosis correction, and functional outcomes. Thirty-seven surgical procedures were done in 31 patients for Meyerding Grade 3 or Grade 4 isthmic dysplastic spondylolisthesis. Patients were separated into two groups based on whether they had structural anterior column support (tricortical autogenous iliac crest) in addition to posterior fusion surgery. Group 1 consisted of 18 patients treated only with posterior surgery without anterior structural support (11 patients were treated with L4-sacrum posterior in situ fusion and seven patients were treated with posterior instrumented reduction with decompression and posterior fusion), and Group 2 consisted of 19 patients who had a reduction and circumferential fusion including anterior structural support. All patients had new radiographs taken at the time of followup (average, 3.1 years, range, 2 years-10 years 1 month) and completed a functional outcome questionnaire. The incidence of pseudarthrosis was 39% (seven of 18 patients) in Group 1 and 0% (0 of 19) in Group 2. All seven patients who had pseudarthrosis achieved solid fusion with a second procedure involving circumferential fusion with anterior column structural grafting. Outcomes regarding pain after treatment, function, and satisfaction were high in those patients who achieved solid fusion regardless of surgical procedure.  相似文献   
64.
Zusammenfassung Im Behandlungskonzept des Magenkarzinoms kommt der chirurgischen Therapie nach wie vor entscheidende Bedeutung zu. Frühkarzinome vom Mukosatyp können je nach Ausdehnung onkologisch adäquat durch endoskopische Mukosektomie oder limitierte Resektion ohne Lymphadenektomie (LAD) behandelt werden. Lokal fortgeschrittene Magenkarzinome bedürfen einer subtotalen bzw. totalen Magenresektion. Der Stellenwert der erweiterten LAD kann auch nach Vorliegen eines Cochrane-Review nicht abschließend bewertet werden. Eine aktuelle randomisierte Studie aus Japan zeigt übereinstimmend mit der Ergebnissen der Deutschen Magenkarzinomstudie, dass bei ausreichender Erfahrung die erweiterte LAD mit geringer Morbidität und Mortalität durchgeführt werden kann. Da in Subgruppen ein Prognosegewinn zu erwarten ist und diese präoperativ nicht sicher identifiziert werden können, sollte die D2-LAD bei allen lokal fortgeschrittenen Karzinomen erfolgen. Die Indikation zur Splenektomie und/oder Pankreaslinksresektion muss aufgrund der bisherigen Studienergebnisse sehr zurückhaltend gestellt werden. Neuere Studien deuten an, dass in Zukunft auch beim Magenkarzinom mit Hilfe der Sentinel-Lymphknoten-Diagnostik die Indikation zur Lymphadenektomie individualisert werden kann.  相似文献   
65.
To test the hypothesis that deficiencies in hypothalamic-pituitary function in genetic hemochromatosis result from cellular injury by iron deposits, we conducted provocative tests in 11 men with genetic hemochromatosis before and after iron depletion by serial phlebotomy and in 10 control subjects. We gave combination intravenous injections of insulin (0.15 U/kg), luteinizing hormone releasing hormone (LHRH, 100 micrograms), and thyrotropin releasing hormone (400 micrograms) and then measured plasma glucose, growth hormone, corticosteroids, follicle-stimulating hormone, luteinizing hormone, prolactin, and thyroid-stimulating hormone at 30-minute intervals for 90 minutes. Phlebotomy caused a substantial decrease in median values for serum ferritin, deferoxamine-chelatable iron, and hepatic iron concentration. Before phlebotomy, stimulation by hypoglycemia and thyrotropin releasing hormone caused significantly less secretion of growth hormone (P = 0.004) and prolactin (P = 0.03) in patients than in control subjects. No significant improvement was noted, however, in growth hormone or prolactin secretion after phlebotomy. Of the 11 patients, 7 had secondary hypogonadism, and phlebotomy did not improve the serum testosterone, follicle-stimulating hormone, luteinizing hormone, or responses to LHRH in any case. Chlorpromazine injections failed to elevate serum prolactin in all patients, and administration of levodopa caused a partial reduction in serum prolactin; thus, the hypothalamus may be an important locus of endocrine malfunction in these patients. We conclude that abnormal hypothalamic-pituitary function in genetic hemochromatosis is not substantially improved by iron-depletion therapy.  相似文献   
66.
67.
Endothelin-1, angiotensin II, and oxygen-derived radicals are pivotal factors in the development and progression of atherosclerosis. In vitro studies suggest that generation of oxygen-derived radicals by angiotensin II is an important mechanism increasing endothelin-1 synthesis, which consecutively may trigger effects such as cell proliferation and hypertrophy. The aim of this study was to confirm our previous data in an ex vivo and an in vivo setting. Explanted segments of internal mammary arteries were analyzed for big endothelin-1 expression following incubation with xanthine oxidase, angiotensin II, superoxide dismutase, and catalase to stimulate or to specifically inactivate oxygen-derived radicals. Endothelin-1 concentrations were determined by immunostaining and enzyme-linked immunosorbent assay. Further, oxypurinol was given to patients undergoing coronary angioplasty, a procedure known to increase plasma endothelin-1 concentrations. Angiotensin II and xanthine oxidase dose-dependently increased big endothelin-1 concentrations (p < .01 and p < .0001); the effects could be inhibited by coincubation with superoxide dismutase and catalase as determined by both semiquantitative immunofluorescence and enzyme-linked immunosorbent assay (p < .01). Patients undergoing coronary angioplasty exhibited significantly elevated big endothelin-1 concentrations 60 minutes after angioplasty (p = .03); in patients also receiving oxypurinol immediately after angioplasty, big endothelin-1 concentrations decreased (p = .001). Our results may explain the association between elevated angiotensin II levels, increased oxidative stress, and increased endothelin-1 concentrations in atherosclerosis. The data therefore support the concept that oxygen-derived free radicals stimulate the release of endothelin-1, which subsequently induces effects such as proliferation and enhanced agonist-induced vasoconstriction, previously attributed directly to angiotensin II.  相似文献   
68.
AIM:To assess the effects of neoadjuvant chemoradiotherapy(CRT) on the presence of extracapsular lymph node involvement(LNI) and its prognostic value in patients with resected esophageal cancer.METHODS:Two hundred and ninety-eight patients with advanced esophageal cancer underwent esophagectomy between 1997 and 2006.One hundred and ninety patients(63.8%) were treated with neoadjuvant CRT prior to resection.A total of 986 metastatic LNs were examined.Survival of the patients was analyzed according to intra-a...  相似文献   
69.
70.

INTRODUCTION

Since the invasion of Iraq in 2003, the conflict has evolved from asymmetric warfare to a counter-insurgency operation. This study investigates the pattern of wounding and types of injuries seen in casualties of hostile action presenting to a British military field hospital during the present conflict.

PATIENTS AND METHODS

Data were prospectively collected on 100 consecutive patients either injured or killed from hostile action from January 2006 who presented to the sole coalition field hospital in southern Iraq.

RESULTS

Eighty-two casualties presented with penetrating missile injuries from hostile action. Three subsequently died of wounds (3.7%). Forty-six (56.1%) casualties had their initial surgery performed by British military surgeons. Twenty casualties (24.4%) sustained gunshot wounds, 62 (75.6%) suffered injuries from fragmentation weapons. These 82 casualties were injured in 55 incidents (mean, 1.49 casualties; range 1–6 casualties) and sustained a total 236 wounds (mean, 2.88 wounds) affecting a mean 2.4 body regions per patient. Improvised explosive devices were responsible for a mean 2.31 casualties (range, 1–4 casualties) per incident.

CONCLUSIONS

The current insurgency in Iraq illustrates the likely evolution of modern, low-intensity, urban conflict. Improvised explosive devices employed against both military and civilian targets have become a major cause of injury. With the current global threat from terrorist bombings, both military and civilian surgeons should be aware of the spectrum and emergent management of the injuries caused by these weapons.  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