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   24306篇
  免费   2183篇
  国内免费   587篇
耳鼻咽喉   355篇
儿科学   497篇
妇产科学   587篇
基础医学   2675篇
口腔科学   367篇
临床医学   2146篇
内科学   3088篇
皮肤病学   526篇
神经病学   719篇
特种医学   1268篇
外国民族医学   22篇
外科学   5836篇
综合类   2665篇
现状与发展   3篇
一般理论   1篇
预防医学   544篇
眼科学   133篇
药学   750篇
  16篇
中国医学   100篇
肿瘤学   4778篇
  2024年   50篇
  2023年   434篇
  2022年   796篇
  2021年   1096篇
  2020年   1060篇
  2019年   960篇
  2018年   985篇
  2017年   882篇
  2016年   965篇
  2015年   936篇
  2014年   1481篇
  2013年   1476篇
  2012年   1176篇
  2011年   1383篇
  2010年   1153篇
  2009年   1202篇
  2008年   1198篇
  2007年   1242篇
  2006年   1088篇
  2005年   965篇
  2004年   881篇
  2003年   724篇
  2002年   638篇
  2001年   498篇
  2000年   383篇
  1999年   351篇
  1998年   352篇
  1997年   283篇
  1996年   273篇
  1995年   212篇
  1994年   210篇
  1993年   173篇
  1992年   169篇
  1991年   194篇
  1990年   140篇
  1989年   120篇
  1988年   108篇
  1987年   104篇
  1986年   88篇
  1985年   110篇
  1984年   84篇
  1983年   60篇
  1982年   78篇
  1981年   63篇
  1980年   54篇
  1979年   49篇
  1978年   42篇
  1977年   46篇
  1976年   24篇
  1972年   8篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
CT图象的面罩式覆盖法定量诊断脂肪肝   总被引:1,自引:0,他引:1  
目的 探讨脂肪肝的脂肪浸润程度的无创性检查方法及临床意义。方法 用 GE 30 0 0 I CT机扫描 36例脂肪肝患者肝脏、脾脏 ,用 CT机配备软件处理数据 ,面罩式覆盖法计算肝脏各个层面的脂肪面积与对应层面肝脏面积 ,并得出比值 (脂肪浸润指数 )。用生化仪检测肝功能指标。肝穿刺病理检测肝组织内脂肪浸润程度。结果 平均脂肪浸润指数与肝功能状态呈显著正相关 ,亦与肝穿刺的病理结果呈正相关 (r=0 .86 5 ,P<0 .0 1)。结论  CT图象面罩式覆盖法对脂肪浸润的定量分析是诊断脂肪肝可靠的无创性检查方法 ,对非均匀性脂肪肝该方法优于肝穿刺  相似文献   
82.
多发性肌炎与皮肌炎25例,其中多发性肌炎21例,皮肌炎2例,多发性肌炎或皮肌炎伴发恶性肿瘤2例。从临床表现、生化检查、肌电图及肌肉活检等方面进行分析,提出多发性肌炎与皮肌炎的诊断条件。本组均采用皮质类固醇治疗,5例合并免疫抑制剂治疗,其中临床治愈4例,显著好转10例,好转5例,无效2例,死亡4例。  相似文献   
83.
As a model system for mucocutaneous lymph node syndrome (MCLS), we have advocated and used mice which had been rendered tolerant to Streptococcus pyogenes-associated antigens by neonatal infection with group A fteta-hemolytic streptococci, because these mice have shown a variety of peculiar bioimmunological characteristics bearing a striking resemblance to those of MCLS patients. The results of our current investigations reaffirmed the reliability of the animal model by indicating that mice subjected to neonatal infection with 5. pyogenes , or inoculation with streptococcal pyrogenic exotoxin (SPE) in Freund's adjuvant, were perfect counterparts of patients with MCLS on account of their platelet activation and hyperaggregability in response to provocative treatment, which are familiar findings in this disease.  相似文献   
84.
A lymph node metastasis in the neck or parotid region from an unknown primary melanoma is an uncommon occurrence. Out of a total of 300 patients with head and neck melanoma treated at the Netherlands Cancer Institute between 1976 and 1992, 17 (5.7%) presented in this way. The most common site for metastatic lymph nodes (18 nodes in 17 patients) was level V (n= 7), followed by the parotid region (n= 4), level II (n= 4), level III (n= 2), and level IV (n= 7). Two patients had local excision of the neck node metastasis only, while the remaining 15 patients underwent more extensive surgical treatment. The 5-year disease-specific survival rate in this group was 48%, with a median survival of 36 months, which is more or less similar to the prognosis of stage II melanoma of the head and neck with a known, surgically treated primary tumour. No relation was found between disease-free interval and sex, the number of positive lymph nodes or the duration of symptoms.  相似文献   
85.
Eccrine spiradenoma is a rather rare adnexal tumor of the skin. When the clinical presentation is that of a breast neoplasm, diagnosis can be difficult. As cytology was a new procedure for this tumor, the approach of choice appeared to be a holistic one. The cytologic picture showed bland groups of uniformly sized cuboid cells with scant cytoplasm, round to ovoid nuclei, and inconspicuous nucleoli, while in the groups rosettelike structures could be discerned. Only by integrating the data of clinical history, inspection, palpation, reaction on breast puncture, and immunologic findings could the diagnosis be made.  相似文献   
86.
Background: Percutaneous closed needle biopsy of musculoskeletal neoplasms has gained in popularity. However, it remains controversial whether or not to resect the needle tract for fear of a local recurrence. A single published case report exists, noting the lone tract recurrence of an extremity skeletal osteosarcoma. Methods: We report on three additional individuals who demonstrated that tract local recurrences may occur after a closed needle biopsy for nonosteosarcoma, nonextremity sarcomas. For perspective, the world literature is reviewed to identify tract recurrences for other malignancies and the results of needle biopsy in musculoskeletal neoplasms. Results: Eighty-nine percent of needle tract local recurrences occur when carcinomas are subjected to biopsy, as reported in the literature. Forty-seven cases since 1950 are described representing essentially all tumor types. The nature of musculoskeletal neoplasms makes closed biopsy more difficult than for softer, more homogeneous, and easier to access neoplasms. Conclusions: Local recurrences of sarcoma may occur in closed needle biopsy tracts. Strong consideration should be given to open biopsy and tract resection.  相似文献   
87.
Based upon detailed dissections of the lymphatic system in adult cadavers, the lymphatic drainage of the gallbladder was divided into three pathways: (1) The cholecystoretropancreatic pathway, which had two routes, one running spirally from the anterior surface of the common bile duct to the right rear, and the other running almost straight down from the posterior surface of the common bile duct. These routes converged at the principal retroportal node at the posterior surface of the head of the pancreas. (2) The cholecysto-celiac pathway; this was the route running to the left through the hepatoduodenal ligament to reach the celiac nodes. (3) The cholecysto-mesenteric pathway; this was the route running to the left in front of the portal vein to connect with the nodes at the superior mesenteric root. The cholecysto-retropancreatic pathway can be regarded as the main pathway, and the principal retroportal node appeared to be critical as the main terminal node in the visceral lymphatic system of the gallbladder. These three pathways converged with the abdomino-aortic lymph nodes near the left renal vein, and the nodes in the interaortico-caval space were considered to be of particular importance. Offprint requests to: M. Ito  相似文献   
88.
本文报道了子宫内膜活检在诊治不孕症中的作用,并分析了1278例原发性不孕症患者子宫内膜活检后的临床诊断与病理学阳性的关系。其中无排卵性内膜85例占6.2%,黄体功能欠缺50例占3.9%,子宫内膜增生症21例占1.6%,子宫内膜炎8例占0.6%和内膜结核24例占1.8%。文中还对不孕的原因作了进一步的分析与讨论,提出了不孕症的诊治意见。  相似文献   
89.
A new radiolucent device for increased accuracy of CT-guided fine-needle punctures permits precise determination of the optimum angle, depth, and position of the fine needle, which can be preset from the data supplied on the CT monitor. Puncture and repeat scans for controlling the tip of the needle can be performed with the patient in a stationary position. The device is designed as a belt that holds a needle holder sheath and a goniometric scale, both of which can be moved to varying positions around the patient.  相似文献   
90.
杨光  蔡振杰  王晓武  郑奇军  胡军 《医学争鸣》2002,23(20):1905-1907
目的 总结原位心脏移植术后急性排异反应的监测。方法 2000-01/2002-04施行11例原位心脏移植手术,结合临床表现、心电图、超声心动图、化验检查及心内膜活栓等检查,对心脏移植术后急性排异反应的监测进行分析。结果 采用临床症状+心电图+超声心电图+心肌血清学检测综合判断有6次急性排异反应,行心内膜活检证实Ⅰb级2次,Ⅲa级3次;术后常规行心内膜活检21次,仅发现急性排异反应Ⅰa或Ⅰb级5次。结论 急性排异反应是关系到心脏移植术后患者康复及愈后的重要因素,因此要及时、有效地进行监测;心内膜心肌活检是诊断急性排异反应敏感可靠的方法,但为有创性检查,有一定的并发症风险,其他多项无创性检查可作辅助指标,因此急性排异反应监测应把无创性检查与心内膜心肌活检有机地结合起来。  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