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   9512篇
  免费   300篇
  国内免费   12篇
耳鼻咽喉   277篇
儿科学   334篇
妇产科学   407篇
基础医学   629篇
口腔科学   189篇
临床医学   672篇
内科学   2061篇
皮肤病学   325篇
神经病学   588篇
特种医学   667篇
外国民族医学   2篇
外科学   2258篇
综合类   50篇
预防医学   363篇
眼科学   306篇
药学   247篇
中国医学   1篇
肿瘤学   448篇
  2023年   21篇
  2022年   25篇
  2021年   59篇
  2020年   30篇
  2019年   42篇
  2018年   79篇
  2017年   59篇
  2016年   76篇
  2015年   563篇
  2014年   651篇
  2013年   681篇
  2012年   701篇
  2011年   657篇
  2010年   646篇
  2009年   627篇
  2008年   676篇
  2007年   603篇
  2006年   590篇
  2005年   519篇
  2004年   390篇
  2003年   159篇
  2002年   110篇
  2001年   127篇
  2000年   129篇
  1999年   141篇
  1998年   54篇
  1997年   69篇
  1996年   57篇
  1995年   48篇
  1994年   55篇
  1993年   49篇
  1992年   84篇
  1991年   78篇
  1990年   81篇
  1989年   82篇
  1988年   61篇
  1987年   59篇
  1986年   67篇
  1985年   45篇
  1984年   52篇
  1983年   57篇
  1982年   39篇
  1981年   42篇
  1980年   46篇
  1979年   61篇
  1978年   31篇
  1977年   30篇
  1976年   35篇
  1974年   23篇
  1973年   26篇
排序方式: 共有9824条查询结果,搜索用时 406 毫秒
41.
Congenital disorders of glycosylation type I (GDG-I) is a class of genetic multisystem disorders characterised by defective glycosylation of glycoproteins. The characteristics and mechanisms of failure to thrive and intestinal diseases present in CDG-I are anectodal. PATIENTS AND METHODS: The aim of this study was to analyse 7 CDG-I (4 CDG-Ia, 2 CDG-Ib and 1 CDG-Ix) with important digestive symptoms and failure to thrive in order to characterise the mechanisms implied. RESULTS: Four children had no skin abnormality or dysmorphia (1 CDG-Ia, 2 CDG-Ib, 1 CDG-Ix). An encephalopathy with cerebellar hypoplasia was present only in the 4 CDG-Ia. Failure to thrive and diarrhea were present during the first month of life in 6 and appeared at 5 years in one CDG-Ia associated to mild or severe hepatopathy in all patients. One CDG-Ia, 1 CDG-Ib, 1 CDG-Ix had an exsudative enteropathy. A positive steatorrhea was present in 3 patients. Five patients had an abnormal small bowel biopsy. Abnormalities were variable: moderate inflammation of the chorion without villous atrophy in 2, intra-enterocyte fat accumulation without villous atrophy in 2, and partial villous atrophy with lymphangectasia in 1. In 2 CDG-Ia the intestinal biopsy was normal. Enteral nutrition in 4 and parenteral nutrition in 2 were effective in 4 patients and 1 patient with an exsudative enteropathy respond to a free fat diet (CDG-Ix). CONCLUSION: The digestive symptoms with failure to thrive is a common feature of CDG-I and could be the first symptoms. The diagnostic should be suspected if no other cause is found. Mechanisms of the intestinal symptoms appear to be multiple such as inflammation, abnormal enterocyte lipid transport or intestinal permeability related to the abnormal glycosylation of intestinal mucosa glycoproteins.  相似文献   
42.
G Olt  A Berchuck  A P Soisson  C M Boyer  R C Bast 《Cancer》1992,70(8):2137-2142
BACKGROUND. Although the ascites of patients with ovarian cancer has been reported to contain immunosuppressive factors, the identity and source of this activity has not been determined. Previously, the authors showed that conditioned media from two of four epithelial ovarian cancer cell lines inhibits proliferation of mitogen-stimulated human lymphocytes. The physical characteristics of the inhibitory substance are unlike those of peptide growth factors but closely resemble those of fibronectin. METHODS AND RESULTS. In the current study, it was found that the two ovarian cancer cell lines that produce the inhibitory substance have more fibronectin on the cell surface and secrete significantly more immunoreactive fibronectin into their culture media than the other two ovarian cancer cell lines. In addition, the immunosuppressive activity was bound to a gelatin-Sepharose affinity column, known to bind fibronectin. Finally, in ascites from 20 patients with advanced epithelial ovarian cancer, fibronectin levels correlated with the ability to inhibit proliferation of lectin-stimulated lymphocytes (P < 0.001). CONCLUSIONS. Fibronectin is produced by some ovarian cancer cell lines and acts to inhibit proliferation of mitogen-stimulated lymphocytes. Additional studies are needed to clarify the role of fibronectin in ovarian cancer.  相似文献   
43.
Cardiogenic shock remains the major cause of death among patients with acute myocardial infarction. Besides supportive therapy there is clear evidence that revascularization of the infarct related artery should be performed as soon as possible with percutaneous transluminal coronary angioplasty. Placement of coronary stents and administration of platelet glycoprotein IIb/IIIa antagonists may further improve outcome. Intra-aortic balloon pumping should be integral part of this treatment strategy but is unfortunately underused in clinical practice. Routine bypass surgery for cardiogenic shock patients is deferred and restricted to selected patients.  相似文献   
44.
After a fracture of the distal radius, especially with malunion, many patients complain of a decreased range of forearm rotation and pain on the ulnar side of the wrist. The purpose of this article is to describe the therapeutic options available in such cases. Decision making as to whether there is an indication for corrective surgery or not is based on the patient’s symptoms and the clinical findings, whereas the decision as to which surgery to perform must take into account the radiological findings. If possible, reconstruction of the anatomy using a distal radius osteotomy should be carried out.  相似文献   
45.
Zusammenfassung Einleitung: Das Ziel dieser Studie war die Entwicklung eines spezifischen Schweregradklassifizierungssystems für die Beurteilung und Vorhersage von Organfunktionsstörungen und Überleben bei herzchirurgischen Intensivpatienten. Methoden: Hierzu wurden konsekutiv alle erwachsenen Patienten nach einem herzchirurgischen Eingriff unter Einsatz der Herzlungenmaschine über einen Zeitraum von 3 Jahren in die Studie aufgenommen. Im Konstruktionsset erfolgte die Auswahl der Variablen mit Hilfe der Patienten, die mindestens 24 Stunden auf der Intensivstation verbrachten. Die Ergebnisse wurden dann in zwei Validierungssets mit allen Intensivpatienten überprüft. Die Qualität des Scores wurde mit dem Hosmer-Lemeshow-Test (HL) sowie der ROC-Analyse beurteilt, und mit dem APACHE-II- und dem MODS-Score verglichen. Ergebnisse: Insgesamt wurden 3230 Patienten über einen Zeitraum von 3 Jahren auf unserer Intensivstation aufgenommen. Die HL-Werte für den neuen Score waren 5,8 (APACHE-II: 11,3; MODS: 9,7) für das Konstruktionsset, 7,2 (APACHE-II: 8,0; MODS: 4,5) für das Validierungsset I und 5,9 für das Validierungsset II. Die Fläche unter der ROC-Kurve war 0,91 (APACHE-II: 0,86; MODS: 0,84) für den neuen Score im Konstruktionsset, 0,88 (APACHE-II: 0,84; MODS: 0,84) in dem Validierungsset I, und 0,92 in dem Validierungsset II. Schlussfolgerung: Der neue CASUS (Cardiac Surgery Score) zeigt für herzchirurgische Intensivpatienten eine exzellente Kalibrierung und Diskriminierung bezüglich der 30-Tage-Letalität. Die Variablen des CASUS sind einfach, reproduzierbar und werden routinemäßig in herzchirurgischen Intensivstationen erfasst. Der CASUS könnte als Expertensystem für das Diagnostizieren von Organfunktionsstörungen, der Entscheidungsfindung, der Ressourcenauswertung und Vorhersage der Letalität für herzchirurgische Intensivpatienten dienen.  相似文献   
46.
47.
Chronic pruritus (starting from 6 weeks duration) is symptom of dermatological, internal, neurological or psychiatric disease. Identification and treatment of the underlying diseases is of great importance especially in the initial phase of chronic pruritus in order to prevent peripheral and central sensitization processes and thus chronification. Application of the redefined clinical classification, newly defined clinical algorithms and inquiry of clinical characteristics of pruritus is helpful in finding the underlying disease. In chronic pruritus existing for several years, clarifying the underlying origin is difficult and therapies are often ineffective. Next to conventional therapies such as antihistamines and corticosteroids, central effective substances can be applied preventing pruritus sensation on spinal or cerebral level.  相似文献   
48.
Schmerztherapie     
Ohne Zusammenfassung  相似文献   
49.
Wegener’s granulomatosis (WG) is a necrotising granulomatous small vessel vasculitis with a clinical predilection for the involvement of the upper airways, lungs and kidneys. It occurs at all ages. The pathogenesis of WG is determined by the pathological activation of phagocytes during transmigration through the vessel. Whereas most aspects of WG are similar at all ages, some features appear to be significantly different. WG in childhood is more frequently complicated by subglottic stenosis and nasal deformity, while treatment related morbidity is less common compared to adults. The introduction of combined treatment with cyclophosphamide and glucocorticoids has resulted in a dramatic improvement in patient outcome; however, commonly occurring disease relapses and the risk of chronic organ damage at all ages make long-term follow-up of all patients necessary.  相似文献   
50.
A 66-year-old man with atrial fibrillation was referred soon after developing left lower limb and abdominal pain with rectal bleeding. An immediate flush aortogram showed embolic occlusion of the left distal superficial femoral artery and superior mesenteric artery (SMA), 3 cm from its ostium. Recombinant tissue plasminogen activitor (rtPA) 40 mg was selectively in stilled in the SMA in two boluses. Abdominal symptoms resolved within 48 h, and complete recanalization of the SMA was shown on angiography. Exploratory laparotomy after 72 h showed a normal small bowel and right colon, and was completed by femoropopliteal embolectomy. Six months later, the patient remained asymptomatic.  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