全文获取类型
收费全文 | 2862篇 |
免费 | 111篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 65篇 |
妇产科学 | 20篇 |
基础医学 | 410篇 |
口腔科学 | 29篇 |
临床医学 | 147篇 |
内科学 | 710篇 |
皮肤病学 | 66篇 |
神经病学 | 293篇 |
特种医学 | 51篇 |
外科学 | 533篇 |
综合类 | 17篇 |
预防医学 | 50篇 |
眼科学 | 13篇 |
药学 | 193篇 |
中国医学 | 2篇 |
肿瘤学 | 377篇 |
出版年
2023年 | 18篇 |
2022年 | 27篇 |
2021年 | 46篇 |
2020年 | 33篇 |
2019年 | 35篇 |
2018年 | 47篇 |
2017年 | 28篇 |
2016年 | 41篇 |
2015年 | 25篇 |
2014年 | 60篇 |
2013年 | 72篇 |
2012年 | 102篇 |
2011年 | 123篇 |
2010年 | 86篇 |
2009年 | 61篇 |
2008年 | 117篇 |
2007年 | 101篇 |
2006年 | 118篇 |
2005年 | 126篇 |
2004年 | 117篇 |
2003年 | 119篇 |
2002年 | 112篇 |
2001年 | 136篇 |
2000年 | 131篇 |
1999年 | 116篇 |
1998年 | 40篇 |
1997年 | 38篇 |
1996年 | 20篇 |
1995年 | 15篇 |
1993年 | 15篇 |
1992年 | 62篇 |
1991年 | 57篇 |
1990年 | 60篇 |
1989年 | 68篇 |
1988年 | 51篇 |
1987年 | 54篇 |
1986年 | 80篇 |
1985年 | 66篇 |
1984年 | 34篇 |
1983年 | 37篇 |
1982年 | 26篇 |
1981年 | 25篇 |
1980年 | 21篇 |
1979年 | 30篇 |
1978年 | 17篇 |
1977年 | 20篇 |
1975年 | 14篇 |
1970年 | 17篇 |
1969年 | 16篇 |
1968年 | 15篇 |
排序方式: 共有2986条查询结果,搜索用时 15 毫秒
1.
S Tanaka T Nishihara T Nagashima K Kawai S Nakai M Adachi 《Journal of clinical neuroscience》1997,4(1):57-62
The effects of 3,4-dihydro-6-[4-(3,4-dimethoxybenzoyl)-1-piperazinyl]-2(1H)-quinolinone (vesnarinone) on the growth of glioma cells were examined in vitro. Vesnarinone at a dose of 100 mug/ml suppressed the growth of four different glioma cell lines, U-251MG, U-373MG, U-87MG and A-172, by approximately 50%, with an elongation of the cytoplasmic process on day 5 of culture. The long-term culture of U-87MG with 10 mug/ml of vesnarinone was continued up to day 34. Although growth suppression was approximately 25% on day 5, it reached over 95% on day 34. An increase in the cyclic adenosine monophosphate content of glioma cells cultured with vesnarinone was observed by enzyme-linked immunosorbent assay (ELISA). The accumulation of glial fibrillary acidic protein was observed to occur with vesnarinone by ELISA. These findings suggest that vesnarinone suppressed the growth and induced differentiation of glioma cells in vitro. 相似文献
2.
Satoru Miyawaki Ryuichi Yamazaki Takehiko Harada Shigehiko Takanashi Tadashi Nagashima Hiroshi Nakaguchi Ryo Okazaki Kazuhito Yamazaki Yasuo Ishida Akira Matsuno 《Journal of clinical neuroscience》2007,14(5):481-484
Skull metastasis of thyroid carcinoma is rare. The majority of skull metastases of thyroid carcinoma are of the follicular subtype, rather than thyroid papillary carcinoma. In this report, a 55-year-old woman with skull metastasis from thyroid papillary carcinoma is presented. The metastatic lesion of the skull was hypervascular and osteolytic, and the bleeding was profuse during resection. There have been only four reports of skull metastasis from thyroid papillary carcinoma. The mean period from the initial diagnosis of thyroid carcinoma until the detection of skull metastasis is 23.3 years, whereas in this patient, it was about 2 years. Therefore, in the clinical course of thyroid papillary carcinoma, skull metastasis should be considered, and the patient should be meticulously followed up. 相似文献
3.
4.
We have immunohistochemically localized fibronectin, lysozyme and alpha-fetoprotein (AFP) in 21 human hepatocellular carcinoma (HCC) tissues obtained by surgical resection at both light and electron microscopic levels. Three distinct distribution patterns of fibronectin (sinusoidal, periacinar, and pericellular patterns) were observed. The sinusoidal and periacinar patterns were mainly observed in HCC of pseudoglandular or trabecular patterns and of Edmondson's grade I or II, whereas the pericellular pattern was observed in HCC of compact or trabecular patterns and of Edmondson's III grade, suggesting that the pericellular fibronectin was rather associated with undifferentiated HCC. Electron microscopic observation of the pericellular fibronectin showed fibronectin to be present in the dilated intercellular spaces where microvilli were moderately developed. We observed intracytoplasmic staining of fibronectin in 2 of the 21 HCC cases. By immunoelectron microscopy, fibronectin was observed in the endoplasmic reticulum (ER) of some HCC cells. In the 21 HCC cases, lysozyme-positive cancer cells were observed in 10 cases, and AFP in 6 cases. At the ultrastructural level, lysozyme was identified in the ER and the perinuclear spaces of HCC cells, suggesting that lysozyme was synthesized by these cells. Lysozyme-positive cases tended to be more frequently observed in cases with the pericellular pattern of fibronectin rather than those with sinusoidal or periacinar patterns. 相似文献
5.
Genetic alteration in carcinoid tumors of the lung. 总被引:1,自引:0,他引:1
Kenji Sugio Toshihiro Osaki Tsunehiro Oyama Mitsuhiro Takenoyama Takeshi Hanagiri Masaru Morita Koji Yamazaki Akira Nagashima Hisashi Nakahashi Yoshihiko Maehara Kosei Yasumoto 《Annals of thoracic and cardiovascular surgery》2003,9(3):149-154
Surgically resected specimens of 13 carcinoid tumors of the lung including nine typical carcinoids and four atypical carcinoids, and eight salivary gland type carcinomas (six mucoepidermoid carcinomas and two adenoid cystic carcinomas) were analyzed regarding p53 expression, loss of heterozygosity (LOH) in chromosome 3p, 9p, and K-ras mutation. The overexpression of p53 was identified in four atypical carcinoid tumors, one mucoepidermoid carcinoma, and one adenoid cystic carcinoma, however, none of typical carcinoids showed p53 immunoreactivity. LOH in 3p14 was demonstrated in three of seven informative cases in all tumors. LOH in 9p was demonstrated in two of five informative cases in all tumors. Two of three cases with LOH at 3p14 had a poor prognosis, one of which also had LOH at 9p. No mutation of the K-ras gene was observed in any of these tumors. These data thus indicate that p53 overexpression might distinguish atypical carcinoid tumors from typical tumors and might therefore be useful as an adjunct modality in the differential diagnosis of pulmonary carcinoid tumors. The presence of LOH at 3p14 or 9p may thus help to identify lung cancer patients with a poor prognosis. 相似文献
6.
An enzyme-linked immunosorbent assay was developed to detect circulating autoantibodies to three liver cell membrane surface antigens, i.e., liver cell membrane specific antigen (LCM), liver specific lipoprotein (LSP), and Tamm-Horsfall glycoprotein (THGP). In autoimmune chronic active hepatitis (autoimmune CAH), the positive rate and mean titer (normal range, less than 5.5 units) for anti-LCM were 100% and 13.5 units before corticosteroid treatment and 100% and 9.9 units during the treatment. The corresponding values for anti-LSP were 84% and 11.8 units, and 81% and 8.9 units, and those for anti-THGP were 84% and 12.3 units, and 81% and 7.9 units. In an autoimmune CAH patient, elevation of the plasma levels of autoantibodies during the treatment apparently preceded the elevation of alanine aminotransferase (ALT). However, the ALT elevation induced by transcatheter arterial embolization was not associated with the elevation of these autoantibodies in an autoimmune CAH patient with hepatocellular carcinoma. In primary biliary cirrhosis, drug-induced hepatitis, and non-hepatic immunological disorders, the production of the three autoantibodies did not directly correlate with liver cell damage. These findings suggest that the elevation of autoantibodies against LCM, LSP, and THGP can be a useful guide for the prednisolone treatment of autoimmune CAH. 相似文献
7.
Inhibition of HIV-1 infectivity with curdlan sulfate in vitro 总被引:5,自引:0,他引:5
Y Kaneko O Yoshida R Nakagawa T Yoshida M Date S Ogihara S Shioya Y Matsuzawa N Nagashima Y Irie 《Biochemical pharmacology》1990,39(4):793-797
Polymethoxylated flavones and C-glycosyl derivatives isolated from medicinal plants besides other flavonoid compounds were studied for their influence on lipid peroxidation induced by FeSO4+ cysteine in rat liver microsomes. A number of hydroxyflavones (e.g. luteolin); C-glycosyl-flavones (e.g. orientin); methoxyflavones (e.g. gardenin D) and flavonols (e.g. datiscetin), as well as the flavanol leucocyanidol and the biflavone amentoflavone behaved as inhibitors of non-enzymic lipid peroxidation. Structure-activity relationships were established and it was observed that the structural features for active polyhydroxylated compounds were different from those of polymethoxylated flavones, antiperoxidative flavonoids possessing a high lipophilicity. 相似文献
8.
9.
Takahide Nagashima Hideaki Tanaka Masafumi Ito Koichi Hirata Soichi Katayama Kazuo Watanabe 《Clinical neurology》2006,46(1):40-44
We report a patient of relapsing polychondritis (RP) with antecedent aseptic meningitis. A 65-year-old man has developed headache and fever. Neurological examination showed meningeal signs, and cerebrospinal fluid (CSF) examination revealed meningeal inflammation which contained 450 polymorphonuclear cells/microl, 302 mononuclear cells/microl, and 0 red cells/microl, with 79 mg protein/dl. Serologic testing for autoimmune disease as well as the culture and cytology of CSF were negative. He admitted our hospital as having aseptic meningitis and experienced antibiotic therapy. However, his pyrexia continued and he developed repeating visual and hearing impairment reacting to steroid. Three months later, he became behaviorally deaf, and bilateral auricular chondritis occurred with nonerosive seronegative inflammatory polyarthritis. The result of condral biopsy was consistent with the diagnosis of RP showing cartilage surrounded by an intense inflammatory cell response with a decreased number of chondrocytes. A clinical diagnosis was made and prednisolone 60 mg/day was begun with the result of resolution of the auricular chondritis, and slight improvement of his deafness. Aseptic meningitis is a rare complication of RP. Only one report detailed RP patient who had preceding meningitis. RP is a potentially lethal disease resulting from suffocation by airway collapse, the complications of a cardiac large vessel, and so on. For improvement of a life prognosis, an early diagnosis and treatment are indispensable. Although RP is a rare discovery, it is necessary that RP should be taken into consideration and be differentiated as a cause of relapsing aseptic meningitis. 相似文献
10.
JC病毒样颗粒可直接转运进入细胞核 总被引:2,自引:1,他引:1
目的探讨JC病毒(JCV)病毒样颗粒(VLP)是否可以直接转运进入细胞核。方法心用JCV主要外壳蛋白VP1体外表达、重组VIP,在其表面标记异硫氰基荧光素(FTTC),同时在其内部包裹荧光染料Cy3,感染培养的HeLa细胞和SVG细胞,荧光显微镜观察VLP入核转运。结果HeLa和SVG细胞感染包裹Cy3的FTTC-VLP时,FTTC与Cy3同时出现于细胞核内相同部位;而感染FTTC—VP1与Cy3混合物时,FTTC虽可在细胞核内检测到,但Cy3信号几乎消失。包裹Cy3的VIP用SDSPAGE展开,荧光显像后行考马斯亮蓝(CBB)染色,发现Cy3和VLP移行至不同部位,证明Cy3不能与VP1结合,提示VLP以完整的颗粒形式转运进入细胞核。应用包裹外源性DNA的VLP感染培养的HeLa和SVG细胞,发现包裹的DNA在细胞浆和细胞核内均可检测到,提示JCV入核过程与VIP相同。结论VLP可以不经裂解直接转运进入细胞核,JCV入核转运可能与VLP相同。 相似文献