全文获取类型
收费全文 | 22834篇 |
免费 | 1169篇 |
国内免费 | 200篇 |
专业分类
耳鼻咽喉 | 273篇 |
儿科学 | 548篇 |
妇产科学 | 281篇 |
基础医学 | 2879篇 |
口腔科学 | 340篇 |
临床医学 | 1406篇 |
内科学 | 6330篇 |
皮肤病学 | 412篇 |
神经病学 | 1649篇 |
特种医学 | 940篇 |
外科学 | 3913篇 |
综合类 | 82篇 |
预防医学 | 479篇 |
眼科学 | 706篇 |
药学 | 1245篇 |
中国医学 | 37篇 |
肿瘤学 | 2683篇 |
出版年
2023年 | 152篇 |
2022年 | 206篇 |
2021年 | 625篇 |
2020年 | 314篇 |
2019年 | 410篇 |
2018年 | 597篇 |
2017年 | 471篇 |
2016年 | 529篇 |
2015年 | 564篇 |
2014年 | 715篇 |
2013年 | 902篇 |
2012年 | 1403篇 |
2011年 | 1617篇 |
2010年 | 960篇 |
2009年 | 843篇 |
2008年 | 1429篇 |
2007年 | 1497篇 |
2006年 | 1525篇 |
2005年 | 1508篇 |
2004年 | 1500篇 |
2003年 | 1360篇 |
2002年 | 1347篇 |
2001年 | 287篇 |
2000年 | 249篇 |
1999年 | 272篇 |
1998年 | 288篇 |
1997年 | 247篇 |
1996年 | 186篇 |
1995年 | 183篇 |
1994年 | 165篇 |
1993年 | 151篇 |
1992年 | 148篇 |
1991年 | 160篇 |
1990年 | 122篇 |
1989年 | 129篇 |
1988年 | 100篇 |
1987年 | 92篇 |
1986年 | 86篇 |
1985年 | 107篇 |
1984年 | 87篇 |
1983年 | 81篇 |
1982年 | 52篇 |
1981年 | 58篇 |
1980年 | 50篇 |
1979年 | 35篇 |
1978年 | 43篇 |
1977年 | 37篇 |
1975年 | 30篇 |
1973年 | 31篇 |
1971年 | 39篇 |
排序方式: 共有10000条查询结果,搜索用时 359 毫秒
91.
Katsumi Inoue Kenichi Abe Kenji Ando Shinichi Shirai Kei Nishiyama Michio Nakanishi Takashi Yamada Koyu Sakai Yoshihisa Nakagawa Naoya Hamasaki Takeshi Kimura Masakiyo Nobuyoshi Tadaomi Alfonso Miyamoto 《Cardiovascular pathology》2004,13(2):109-115
BACKGROUND: Angiographic regression of luminal narrowing occurs 6 months to 3 years poststenting. However, after 4 years lesions progressed gradually and late restenosis was observed in 28% of 179 Palmaz-Schatz-stented lesions during the past 10 years. Elucidating its pathogenesis is pivotal to developing preventive strategies. METHODS AND RESULTS: Histopathological and immunohistochemical studies were performed in 19 stented coronary arteries obtained from 19 patients autopsied after noncardiac death 2-7 years poststenting. The quality/severity of chronic inflammatory cells (T lymphocytes, macrophages and multinucleated giant cells) infiltration around the stent struts that is observed even in the absence of restenosis depended on the time elapsed from stenting: a) 2 years postprocedure, in spite of angiographic regression during the first year and pathologically expressed as maturation of the neointimal scar, there was chronic inflammatory response evidence: neovascularization and lymphocyte infiltration, b) > or = 3 years: the neointimal smooth muscle cells were sparse with abundant proliferation of collagen fibers. Presence of slight helper/inducer T lymphocytes and mild macrophage infiltration around the stent struts was evident immunohistochemically, c) > or = 4 years: prominent infiltration by lipid-laden macrophages with strong collagen-degrading matrix metalloproteinase immunoreactivity was observed around the struts. In two of these arteries, the surface contacting the stent was focally disrupted and covered by nonocclusive mural thrombi. CONCLUSIONS: Stainless steel stents evoke a remarkable foreign-body inflammatory reaction to the metal. These persistent peri-strut chronic inflammatory cells may accelerate new indolent atherosclerotic changes and consequent plaque vulnerability. 相似文献
92.
Rapid serodiagnosis of active pulmonary Mycobacterium tuberculosis by analysis of results from multiple antigen-specific tests 总被引:5,自引:0,他引:5
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Okuda Y Maekura R Hirotani A Kitada S Yoshimura K Hiraga T Yamamoto Y Itou M Ogura T Ogihara T 《Journal of clinical microbiology》2004,42(3):1136-1141
We have prospectively analyzed three antigens for serodiagnosis of tuberculosis (TB). These antigens were tuberculous glycolipid antigen, lypoarabinomannan polysaccharide antigen, and antigen 60 (A60), which was derived from purified protein derivatives. Of the 131 patients with active pulmonary TB, 57 were both smear and culture negative and 14 had chronic active pulmonary TB that remained smear positive for >12 months of chemotherapy. One hundred twenty healthy adults were controls. The percentages of patients positive in all three tests were 58.8% for smear-positive active pulmonary TB and 71.4% for chronic active pulmonary TB. When the results of the three serodiagnostic tests were evaluated in combination, the sensitivity increased to 91.5% in patients with active pulmonary TB and to 86.0% in smear- and culture-negative patients. The false-positive rate of the three-test combination was 12.5% in the healthy control groups. In conclusion, it was not possible to detect all of the antibodies against antigenic substances in the cell walls of the tuberculous bacilli in the sera of all TB patients by using available serodiagnostic tests. However, the combined use of tests with three separate antigens maximizes the effectiveness of serodiagnosis. 相似文献
93.
Mostly separate distributions of CLAC- versus Abeta40- or thioflavin S-reactivities in senile plaques reveal two distinct subpopulations of beta-amyloid deposits
下载免费PDF全文
![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Kowa H Sakakura T Matsuura Y Wakabayashi T Mann DM Duff K Tsuji S Hashimoto T Iwatsubo T 《The American journal of pathology》2004,165(1):273-281
Collagenous Alzheimer amyloid plaque component (CLAC) is a unique non-Abeta amyloid component of senile plaques (SP) derived from a transmembrane collagen termed CLAC-precursor. Here we characterize the chronological and spatial relationship of CLAC with other features of SP amyloid in the brains of patients with Alzheimer's disease (AD), Down syndrome (DS), and of PSAPP transgenic mice. In AD and DS cerebral cortex, CLAC invariably colocalized with Abeta42 but often lacked Abeta40- or thioflavin S (thioS)-reactivities. Immunoelectron microscopy of CLAC-positive SP showed labeling of fibrils that are more loosely dispersed compared to typical amyloid fibrils in CLAC-negative SP. In DS cerebral cortex, diffuse plaques in young patients were negative for CLAC, whereas a subset of SP became CLAC-positive in patients aged 35 to 50 years, before the appearance of Abeta40. In DS cases over 50 years of age, Abeta40-positive SP dramatically increased, whereas CLAC burden remained at a constant level. In PSAPP transgenic mice, CLAC was positive in the diffuse Abeta deposits surrounding huge-cored plaques. Thus, CLAC and Abeta40 or thioS exhibit mostly separate distribution patterns in SP, suggesting that CLAC is a relatively early component of SP in human brains that may have inhibitory effects against the maturation of SP into beta-sheet-rich amyloid deposits. 相似文献
94.
Evaluation of anti-parvovirus B19 activity in sera by assay using quantitative polymerase chain reaction 总被引:4,自引:0,他引:4
Saito T Munakata Y Fu Y Fujii H Kodera T Miyagawa E Ishii K Sasaki T 《Journal of virological methods》2003,107(1):81-87
Human parvovirus B19 (B19) infects cells of erythroid lineage. Production of neutralizing antibodies (Abs) is indispensable for recovery from B19-related disease state. In this study, we used a convenient method to measure neutralizing activities in human sera by using a real-time quantitative PCR based assay. Erythroid cell line KU812Ep6 was incubated with test sera before infection with B19 virus. The copy number of B19-DNA in cultures was decreased in the presence of the sera from patients who recovered from acute B19 infection, whereas no decrease in B19-DNA was in cultures incubated with sera from healthy volunteers who had no B19 infection. The decrease in B19-DNA copy number was calculated and the inhibition percentage was expressed as neutralizing activity to B19. A clinical study showed that the levels of neutralizing ability were high in patients who recovered soon after acute B19 infection, but were low in some patients with a prolonged clinical course for recovery from B19 infection. This method is simple and convenient compared with methods described previously, showing its usefulness to evaluate the neutralizing activity to B19. 相似文献
95.
Tadao Funato Sanae Tsukamoto Takeshi Sasaki 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(3):225-230
The diagnosis of rheumatic diseases is primarily based on clinical symptoms and laboratory findings. However, diagnosis of rheumatic disease is often difficult because of the variations even in the same disease. Routine laboratory tests are valuable in detecting renal dysfunctions. In this review, the important auto-antibodies and inflammatory markers associated with rheumatic diseases are described. Further, their utility as diagnostic and prognostic tools, including their specificity, sensitivity and practical applications, is discussed. 相似文献
96.
Hashii Koji; Fujiwara Hiroshi; Yoshioka Shinya; Kataoka Nobuhiko; Yamada Shigetoshi; Hirano Takeshi; Mori Takahide; Fujii Shingo; Maeda Michiyuki 《Human reproduction (Oxford, England)》1998,13(10):2738-2744
Human luteal cells have been reported to express human leukocyteantigen-DR and lymphocyte functional antigen-3 on the cell surface,suggesting physiological interaction between luteal cells andT-lymphocytes through the menstrual cycle into early pregnancy.To elucidate the role of peripheral lymphocytes on corpus luteumdifferentiation, the effect of peripheral blood mononuclearcells (PBMC) on steroidogenesis by luteal cells was investigated.The production of Th-2 cytokines such as interleukin (IL)-4and IL-10 by the co-cultured cells was also examined, and theeffects of these cytokines on progesterone production by lutealcells were investigated. Corpora lutea were obtained from eightnon-pregnant women in the luteal phase and five women in earlypregnancy for luteal cell culture. PBMC were isolated from unrelatedwomen in the follicular phase, secretory phase, and early pregnancy.After co-culture with allogenic PBMC for 48 h, progesteroneproduction was significantly enhanced by PBMC from the secretoryphase and early pregnancy in the non-pregnant luteal cell culture.In the pregnant luteal cell culture, a significant increasein progesterone production was also observed by the co-culturewith PBMC from women in early pregnancy, showing that PBMC havea luteotrophic effect. The stimulatory effects of PBMC werealso observed in co-culture conditions which prevented directcell-to-cell interaction with luteal cells, showing the minorinfluence of mixed lymphocyte reaction. By co-culture with PBMC,the production of IL-10, but not IL-4, was significantly augmentedin luteal cell culture derived from non-pregnant women, whereasthe production of both IL-4 and IL-10 was significantly enhancedin the luteal cell culture derived from pregnant women. Moreover,IL-4 and IL-10 promoted progesterone production by culturedluteal cells, especially in the luteal cell culture derivedfrom corpora lutea of early pregnancy. These findings indicatethat PBMC stimulate progesterone production by luteal cellsand suggest the involvement of PBMC in corpus luteum functionand differentiation probably via the Th-2-type lymphocytes. 相似文献
97.
Tomoko Morikawa Ichiro Yamadori Takeshi Okino Tetsuro Ogino Masaki Ohmori 《Pathology international》1992,42(4):242-248
Two cell lines designated IC KMS and D KMS were established from human adenovirus type 12 induced tumors of C3Hf/OK mouse. The cell lines retained the characteristics of the original tumor i.e., production of numerous C type and intracisternal A-type particles, integration of Adl2 El region DNA and amplification of the myc gene family. Chromosomal analysis revealed chromosome aberrations in both IC KMS and D KMS cells. The modal chromosome number of IC KMS cells was 54 and that of D-KMS cells was 48. Metacentric chromosomes and mini-chromosomes were found. Trisomy of chromosome 3, 7 and 12 was seen frequently in D KMS cells. Although DNA aneuploidy was revealed by flow cytometry, the DNA indices of these cells showed no relation to the copy number of integrated Adl2 DNA. These cells have been propagated by serial culture during the past 17 months. Production of endogenous virus particles is a unique characteristic of IC KMS and D KMS cells. These cell lines would be useful materials for examining the contribution of Adl2 carcinogenesis to activation of endogenous virus particles, and also the correlation between Adl2 carcinogenesis and cancer related genes. Acta Pathol Jpn 42: 242-248, 1992. 相似文献
98.
Atsushi Kikkawa Toshikazu Takata Takeshi Endo 《Macromolecular chemistry and physics.》1991,192(3):655-662
Cationic polymerization of styrene in the presence of 1-(p-methoxybenzyl)tetrahydrothiophenium hexafluoroantimonate ( 3 ) as an efficient cationic initiator was investigated. 3 was synthesized in an excellent yield by the reaction of p-methoxybenzyl bromide with tetrahydrothiophene and the subsequent exchange of bromide ions for hexafluoroantimonate ions. In the polymerization of styrene, 3 acted as a potent thermally latent initiator which initiates the polymerization at a slightly higher temperature than room temperature, although no polymerization occurs at room temperature for 30 min. 3 is a much more active initiator than the previously reported benzylsulfonium salt 1 . The enhanced activity of 3 was also confirmed in the polymerization of glycidylb phenyl ether. 相似文献
99.
Namiki T Yanagawa S Izumo T Ishikawa M Tachibana M Kawakami Y Yokozeki H Nishioka K Kaneko Y 《Cancer Genetics and Cytogenetics》2005,157(1):1-11
To clarify the correlation of genomic alterations with clinical and histological features, we performed metaphase comparative genomic hybridization analysis on 20 primary cutaneous melanomas, which were obtained by laser capture or manual microdissection, and 16 melanoma cell lines. There were no differences in the average number of aberrations between acral melanomas (AM) and non-AM, although gains of 5q and 11q13 were more frequent (P=0.05) and 10q loss was less frequent (P=0.01) in AM than in non-AM. Although tumor thickness is considered a measurable estimate of clinical expression, there were no differences in the average number of aberrations among 4 groups, classified by thickness of the tumor. While the majority of aberrations were equally distributed among the 4 groups, 6p gains were found only in the thickest tumors. Patients with 6p or 1q gains had a lower overall survival rate than those without them (P=0.0002 or P=0.013). While gains of 1q, 2q, 3p, 3q, 7q, 20p, and 20q were more frequent in the cell lines than in the primary tumors (P<0.01), losses of 6q, 9p, 10p, and 10q were equally found in both cell lines and primary tumors. The present study showed that chromosomal aberrations had already occurred in the thinner tumors, and that 6p and 1q gains may be a prognostic factor. 相似文献
100.
Therapeutic effect of topical administration of SN50, an inhibitor of nuclear factor-kappaB, in treatment of corneal alkali burns in mice 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《The American journal of pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Saika S Miyamoto T Yamanaka O Kato T Ohnishi Y Flanders KC Ikeda K Nakajima Y Kao WW Sato M Muragaki Y Ooshima A 《The American journal of pathology》2005,166(5):1393-1403
We evaluated the therapeutic efficacy of topical administration of SN50, an inhibitor of nuclear factor-kappaB, in a corneal alkali burn model in mice. An alkali burn was produced with 1 N NaOH in the cornea of C57BL/6 mice under general anesthesia. SN50 (10 microg/microl) or vehicle was topically administered daily for up to 12 days. The eyes were processed for histological or immunohistochemical examination after bromodeoxyuridine labeling or for semi-quantification of cytokine mRNA. Topical SN50 suppressed nuclear factor-kappaB activation in local cells and reduced the incidence of epithelial defects/ulceration in healing corneas. Myofibroblast generation, macrophage invasion, activity of matrix metalloproteinases, basement membrane destruction, and expression of cytokines were all decreased in treated corneas compared with controls. To elucidate the role of tumor necrosis factor (TNF)-alpha in epithelial cell proliferation, we performed organ culture of mouse eyes with TNF-alpha, SN50, or an inhibitor of c-Jun N-terminal kinase (JNK) and examined cell proliferation in healing corneal epithelium in TNF-alpha-/- mice treated with SN50. An acceleration of epithelial cell proliferation by SN50 treatment was found to depend on TNF-alpha/JNK signaling. In conclusion, topical application of SN50 is effective in treating corneal alkali burns in mice. 相似文献