全文获取类型
收费全文 | 402951篇 |
免费 | 26211篇 |
国内免费 | 4831篇 |
专业分类
耳鼻咽喉 | 5342篇 |
儿科学 | 8439篇 |
妇产科学 | 10298篇 |
基础医学 | 55855篇 |
口腔科学 | 12122篇 |
临床医学 | 33340篇 |
内科学 | 81638篇 |
皮肤病学 | 8680篇 |
神经病学 | 28407篇 |
特种医学 | 14753篇 |
外国民族医学 | 100篇 |
外科学 | 63323篇 |
综合类 | 14140篇 |
现状与发展 | 5篇 |
一般理论 | 65篇 |
预防医学 | 19111篇 |
眼科学 | 10074篇 |
药学 | 33603篇 |
25篇 | |
中国医学 | 3541篇 |
肿瘤学 | 31132篇 |
出版年
2021年 | 3801篇 |
2020年 | 2579篇 |
2019年 | 3529篇 |
2018年 | 5337篇 |
2017年 | 4148篇 |
2016年 | 4262篇 |
2015年 | 5112篇 |
2014年 | 7044篇 |
2013年 | 8547篇 |
2012年 | 11644篇 |
2011年 | 12086篇 |
2010年 | 7394篇 |
2009年 | 6795篇 |
2008年 | 10694篇 |
2007年 | 11582篇 |
2006年 | 11432篇 |
2005年 | 10534篇 |
2004年 | 9556篇 |
2003年 | 9401篇 |
2002年 | 8855篇 |
2001年 | 28735篇 |
2000年 | 29339篇 |
1999年 | 24328篇 |
1998年 | 5593篇 |
1997年 | 4680篇 |
1996年 | 4146篇 |
1995年 | 3771篇 |
1994年 | 3399篇 |
1993年 | 3008篇 |
1992年 | 16223篇 |
1991年 | 14963篇 |
1990年 | 14282篇 |
1989年 | 14081篇 |
1988年 | 12675篇 |
1987年 | 12147篇 |
1986年 | 11156篇 |
1985年 | 10375篇 |
1984年 | 6933篇 |
1983年 | 5609篇 |
1982年 | 2725篇 |
1979年 | 5482篇 |
1978年 | 3347篇 |
1977年 | 2971篇 |
1975年 | 2641篇 |
1974年 | 3065篇 |
1973年 | 2865篇 |
1972年 | 2828篇 |
1971年 | 2773篇 |
1970年 | 2510篇 |
1969年 | 2543篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
A severe case of Vogt-Koyanagi-Haradi's disease was treated with a combination therapy of cyclosporin A and steroid. The therapy was successful and showed no side effects. 相似文献
942.
943.
944.
Altered angiotensin-II receptors in human hepatocellular and hepatic metastatic colon cancers. 总被引:1,自引:0,他引:1 下载免费PDF全文
OBJECTIVE: To characterize angiotensin-II receptor density and affinity in normal and cirrhotic livers and in hepatocellular and metastatic colorectal cancer. SUMMARY BACKGROUND DATA: Several studies have indicated a possible beneficial effect of angiotensin-II as a biologic response modifier in the treatment of hepatic or metastatic colon cancer. This is based on evidence that angiotensin-II will cause a selective increase in arterial vasoconstriction in normal liver compared with tumor. METHODS: Human hepatoma (5), metastatic colon (10), or cirrhotic (3) liver was obtained. Non-tumor-bearing regions served as normal liver. Angiotensin-II receptor binding was determined on membranes with 125I-angiotensin-II and in situ studies were performed using the biotin-avidin detection system. RESULTS: Angiotensin-II receptor density was markedly down-regulated in tumor compared with normal or cirrhotic liver. CONCLUSIONS: A loss of angiotensin-II receptors occurs on the neovasculature of hepatic tumors. 相似文献
945.
946.
The presence of vascular permeability factors in the extracellular products (ECP) of 10 strains of Renibacterium salmoninarum with different geographical origin and serological characteristics are reported. All the ECP produced haemorrhagic and/or oedematous zones at the injection site with a diameter ranging from 10-30 mm. However, the ECP samples did not display toxic effect in fish at the same dose as inoculated in rabbit (180-400 micrograms protein/0.1 ml). No differences were observed in the production of this dermatotoxic factor between the two antigenic groups found in this microorganism. Whereas heating (80 and 100 degrees C/15 min) the ECP samples resulted in a complete loss of their proteolytic activity, only a decrease (but not total inactivation) of the dermatotoxic effects was detected. Therefore, although proteases could be implicated in the permeability factor, they are not totally responsible for this activity. 相似文献
947.
A patient with chronic lymphocytic leukemia (CLL) and essential thrombocythemia is described. The two disorders were diagnosed synchronously. This association was not treatment related. Review of the literature revealed an additional 9 case reports of CLL associated with myeloproliferative disorders, but none with essential thrombocythemia. 相似文献
948.
Lipopolysaccharide-dependent and lipopolysaccharide-independent pathways of monocyte desensitisation to lipopolysaccharides 总被引:1,自引:0,他引:1
The present study demonstrates that with time in culture blood monocytes (MO) lose their ability to express procoagulant activity (PCA) and secrete tumor necrosis factor-alpha (TNF alpha) in culture medium in response to lipopolysaccharide (LPS) stimulation. Thus, upon 10 micrograms/ml LPS stimulation for 4 hours 2-day-old MO produced lower levels of PCA and TNF alpha than fresh MO. The decrease in responsiveness was not caused by cell death, since in the case of TNF alpha it was fully reversible by interferon-gamma (IFN-gamma). Compared with cells pre-incubated in medium alone, the responsiveness of MO pre-incubated in LPS was further decreased. Thus, in MO LPS pre-incubation was followed by an LPS refractory state. It was expected that the decrease in responsiveness induced by cultivation in medium alone was mediated by LPS contamination of culture medium. However, as we were unable to prevent this decrease by neutralizing LPS contamination of the culture medium with polymyxin B, the loss in LPS-induced activities of cultured MO is likely to be mediated by culture conditions other than LPS contamination. Taken together the present data demonstrate that LPS-dependent as well as LPS-independent pathways of MO desensitization to LPS exist. 相似文献
949.
J Shimizu Y Watanabe M Oda Y Hayashi T Iwa R Kamimura T Takashima 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(10):1349-1353
A case of pulmonary varices in a 73-year-old female is presented. Routine chest X-ray revealed a mass in the right hilar region. CR tomogram showed a round, clearly defined mass at the right hilum. Computed tomography demonstrated marked enlargement of the proximal portion of the pulmonary vein at the entrance of the left atrium, which was suspected to be pulmonary varices. The diagnosis was confirmed by pulmonary angiography. During the arterial phase no abnormal findings were seen, but during the venous phase the veins of the right upper and middle lobes were found to be draining into the dilated pulmonary vein and then into the left atrium. Thus, the diagnosis of pulmonary varices was established. CT and angiography are the most useful methods for definitive diagnosis of pulmonary varices. 相似文献
950.
T Terashima Y Suzuki A Kawai K Yamaguchi T Yokoyama 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(2):276-281
A 48-year-old woman was admitted because of increased bloody sputum. Since she had had a history of repeated thrombotic episodes including venous thrombosis in the lower limbs (21 year old) and pulmonary emboli developing into pulmonary infarction (41 years old), the patient was treated with anti-coagulant therapy using Warfarin for 7 years. Warfarin was discontinued after admission and heparin was administered instead at a relatively low dose of 5,000 units daily, resulting in a considerable diminution of hemoptysis. Unfortunately however, it caused a relapse of active thrombosis associated not only with a significant increase of the product of fibrinolysis (FDP), LDH and GOT but with a concomitant decrease of the platelet count. Hematological examinations concerning coagulation and fibrinolysis remained within a normal range except for the serum concentration of antithrombin III (AT III) and its functional property with regard to the heparin cofactor, which were 8.8 mg/dl and 48%, respectively. Since the findings were consistent with congenital deficiency of AT III, some members of her family were also examined. The concentration of AT III and its activity in the patient's son and her daughter deteriorated in a similar manner, indicating that this was a definite case of congenital deficiency of AT III. The clinical manifestations of 87 cases with congenital AT III deficiency, belonging to 24 families reported in Japan were reviewed. 相似文献