全文获取类型
收费全文 | 3956篇 |
免费 | 234篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 47篇 |
儿科学 | 70篇 |
妇产科学 | 42篇 |
基础医学 | 605篇 |
口腔科学 | 82篇 |
临床医学 | 227篇 |
内科学 | 946篇 |
皮肤病学 | 90篇 |
神经病学 | 270篇 |
特种医学 | 176篇 |
外科学 | 494篇 |
综合类 | 18篇 |
预防医学 | 108篇 |
眼科学 | 134篇 |
药学 | 305篇 |
中国医学 | 10篇 |
肿瘤学 | 587篇 |
出版年
2023年 | 39篇 |
2022年 | 86篇 |
2021年 | 125篇 |
2020年 | 66篇 |
2019年 | 86篇 |
2018年 | 104篇 |
2017年 | 83篇 |
2016年 | 96篇 |
2015年 | 77篇 |
2014年 | 118篇 |
2013年 | 147篇 |
2012年 | 222篇 |
2011年 | 250篇 |
2010年 | 150篇 |
2009年 | 88篇 |
2008年 | 195篇 |
2007年 | 169篇 |
2006年 | 211篇 |
2005年 | 187篇 |
2004年 | 202篇 |
2003年 | 184篇 |
2002年 | 188篇 |
2001年 | 108篇 |
2000年 | 122篇 |
1999年 | 86篇 |
1998年 | 48篇 |
1997年 | 40篇 |
1996年 | 34篇 |
1995年 | 25篇 |
1994年 | 20篇 |
1993年 | 20篇 |
1992年 | 64篇 |
1991年 | 62篇 |
1990年 | 67篇 |
1989年 | 74篇 |
1988年 | 41篇 |
1987年 | 36篇 |
1986年 | 47篇 |
1985年 | 36篇 |
1984年 | 32篇 |
1983年 | 28篇 |
1981年 | 14篇 |
1980年 | 14篇 |
1979年 | 20篇 |
1978年 | 7篇 |
1974年 | 7篇 |
1973年 | 9篇 |
1972年 | 8篇 |
1971年 | 8篇 |
1967年 | 10篇 |
排序方式: 共有4211条查询结果,搜索用时 15 毫秒
21.
22.
The immunohistochemical localization of three triplet proteins of neurofilaments in normal Kultschitsky cells and tumourlets of the human lung has been studied using avidin-biotin-peroxidase complex (ABC) method. Kultschitsky cells and tumourlets have been stained with antisera against 68 K, 150 K and 200 K dalton components of the neurofilaments, respectively. Ultrastructural observations of human Kultschitsky cells have revealed the presence of bundles of intermediate filaments as well as microtubules and neurosecretory-type granules. In the tumourlets, similarly sized filaments were found, but were relatively scarce. Since intermediate filaments are thought to be specific to differentiated cells and neurofilament proteins are restricted to the neuronal tissues, we conclude that Kultschitsky cells of the lung are of neuronal nature. 相似文献
23.
M Kitano G Landini I Semba A Urago K Sugihara H Mukai S Yamashita 《Acta pathologica japonica》1990,40(8):588-595
A mandibular eosinophilic granuloma in a 16-year-old male is reported. This case showed rapid regression, which was clearly demonstrated by histopathological examinations of both preoperative biopsy and surgical materials. Transformation from an eosinophilic granuloma to a xanthomatous granuloma with multinucleated giant cells was observed after only 26 days. Special staining of paraffin sections with peanut agglutinin (PNA) and use of electron microscopy showed that the main component of the lesion in the biopsy material was Langerhans-type histiocytes. These cells had disappeared from the lesion by the time of the operation. At the same time, the number of infiltrating eosinophils was also markedly reduced. It seems appropriate to consider that the rapid regression of this disease was correlated with the rapid reduction in the number of Langerhans-type histiocytes appearing in the granulomatous foci, as well as the number of infiltrating eosinophils. 相似文献
24.
Recent evidence has accumulated which definitively shows that chemokine receptors CCR5 and CXCR4 play an essential role as coreceptors for human immunodeficiency virus type 1 (HIV-1) infection. Flow cytometric analysis permitted us to detect CD38, a surface marker of early differentiation, as well as activation of T cells, on about half of healthy donor-derived CD4(+) T cells. In this study, we focused on the susceptibility of CD38(+) and CD38(-) subsets of CD4(+) T cells to HIV-1 infection with different coreceptor tropisms. About 20% of peripheral blood mononuclear cell-derived resting CD4(+) T cells were recovered into the CD38(+) subset fraction by panning with a monoclonal antibody to CD38. Most of the cells in this CD38(high) fraction also expressed CD45RA and CD62L at higher intensities compared with those of CD38(low) fraction. CCR5(+) T cells predominated in the CD38(-) subset, although cell surface expression of CD4 and CXCR4 was almost similar between both subsets. This difference was consistent with a significantly higher susceptibility of the CD38(-) subset to a macrophage (M)-tropic HIV-1 strain. In contrast, it was shown that a T-tropic strain of HIV-1 could replicate more efficiently in the CD38(+) subset, although viral adsorption rates were similar between both subsets. Thus, the differential susceptibility of CD4(+) T cells to M(-) and T-tropic HIV-1 was associated with their surface expression of CD38. 相似文献
25.
RNA was extracted from tissues processed by a new fixation and paraffin-embedding method (the AMeX method) and examined by Northern blot analysis and slot-blot analysis. The RNA extraction method for AMeX-processed tissue sections after the deparaffinization step was the same as that for fresh materials. The total amount of cellular RNA extracted from AMeX-processed mouse liver tissue was slightly less than that extracted from fresh tissue. In tissues of malignant lymphoma, the total amount of cellular RNA extracted from 25 sections each 20 microns thick was about 1.6-1.8 micrograms/mm2, regardless of the histological subtype and period of storage. The extracted RNA was moderately degraded, and usually could not be used for Northern blot hybridization analysis. The intensity of ethidium bromide staining and the hybridization signals of RNA extracted from AMeX-processed tissues were usually reduced in comparison with RNA from fresh material, but specific signals could be detected by slot-blot hybridization analysis. We have demonstrated previously that the AMeX method preserves high-molecular-weight DNA and various antigens. Since the present study showed that information on mRNA can be obtained from AMeX-processed tissue, the versatility and usefulness of this method were further proven. 相似文献
26.
Rieko Nishimura Takahiro Hasebe Shigeru Imoto K. Mukai 《Virchows Archiv : an international journal of pathology》1998,432(1):89-93
A malignant phyllodes tumour with a noninvasive ductal carcinoma component is reported. The patient was an 80-year-old Japanese
woman with a breast tumour detected by routine physical examination. A simple mastectomy was performed. The excised tumour
was 10.5×9.4×5.4 cm in size and bulged into the skin with ulceration. The macroscopic appearance was that of a phyllodes tumour.
Histologically the tumour consisted mainly of stromal components with a leaf-like structure lined by atypical ductal epithelium.
The epithelial component showed gradual evolution to intraductal papillary carcinoma in a few areas. The stromal component
was composed mainly of fibrosarcoma with areas of osteosarcoma and rhabdomyosarcoma. Neither stromal invasion of intraductal
carcinoma nor transition between the stromal and epithelial elements was seen. Three months after the operation, death occurred,
with multiple pulmonary and subcutaneous metastases. This case probably represents malignant change in both the stromal and
the epithelial components of a phyllodes tumour. Since the two elements were independent, the possibility that a phyllodes
tumour may be one of the origins of true carcinosarcoma is raised.
Received: 11 March 1997 / Accepted: 5 May 1997 相似文献
27.
Shimada M Hino F Yamamoto J Mukai H Hosobe T Onodera S Hoshina S Machida K 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(11):1061-1067
The isothermal and chimeric primer-initiated amplification of nucleic acids (ICAN) is a new isothermal DNA amplification method composed of exo Bca DNA polymerase, RNaseH and DNA-RNA chimeric primers. We developed the simultaneous detection system for Chlamydia trachomatis/Neisseria gonorrhoeae DNA, combined with luminescence detection by a probe hybridization. In the performance tests, this system was able to detect 10 to 100 copies of C. trachomatis/N. gonorrhoeae DNA for only 3.5 hours, and was highly specific to C. trachomatis/N. gonorrhoeae without any cross-reaction to C. pneumoniae, N. lactamica, N. sicca or N. meningitidis. When we tested 60 clinical samples of urine and cervical swabs, the interpretive results were completely consistent with those obtained by Roche PCR system. Of 13 positive samples by the ICAN and PCR systems for C. trachomatis, four were negative by EIA method(IDEIA Chlamydia). These results indicate that the ICAN system is an efficient and sensitive system to simultaneously detect C. trachomatis/N. gonorrhoeae DNA. 相似文献
28.
Immunohistochemical and clonal analysis of minute pulmonary meningothelial-like nodules 总被引:2,自引:0,他引:2
The histogenesis of meningothelial-like nodule or so-called minute pulmonary chemodectoma remains unclear, with various immunohistochemical analyses giving inconsistent results. We performed an immunohistochemical and clonal analysis of minute pulmonary meningothelial-like nodules. Thirty-one histologically defined meningothelial-like nodules in 14 cases were stained immunohistochemically. One case had multiple lesions with brown pigment granules, which were positively stained with Berlin blue method, indicating the presence of hemosiderin. All meningothelial-like nodules were positive for vimentin and epithelial membrane antigen (EMA), but not for S-100 protein, chromogranin A, or synaptophysin. Five of 13 cases (13 of 28 lesions) were positive for CD68 by KP-1. Ten cases (24 lesions) stained for CD68 by PG-M1 were weakly positive. All lesions were negative for lysozyme, myosin, actin, keratin, and melanoma-associated antigen. Alveolar macrophages were intensely positive for CD68 and lysozyme in all examined cases. We analyzed the clonality of 11 minute pulmonary meningothelial-like nodule lesions in two female cases based on an X-chromosome-linked polymorphic marker, the human androgen receptor gene (HUMARA). The HUMARA was found to be amplified with or without prior digestion by the methylation-sensitive restriction endonuclease HpaII. Six of 11 lesions showed monoclonal expansion. Five lesions in a multiple case showed different patterns of monoclonality. Our findings showed that minute pulmonary meningothelial-like nodules have meningothelial-like and phagocytic characteristics but no muscular phenotype. Furthermore, some minute pulmonary meningothelial-like nodules may show monoclonal expansion, whereas others are polyclonal. Our data indicate that minute pulmonary meningothelial-like nodules are reactive rather than neoplastic. 相似文献
29.
30.
The AMeX method. A simplified technique of tissue processing and paraffin embedding with improved preservation of antigens for immunostaining. 总被引:20,自引:7,他引:20 下载免费PDF全文
Y. Sato K. Mukai S. Watanabe M. Goto Y. Shimosato 《The American journal of pathology》1986,125(3):431-435
A new simplified tissue processing method for immunostaining was devised. Tissues were fixed in acetone at -20 C overnight, then cleared in methyl benzoate and xylene, consecutively, and embedded in ordinary paraffin at 58-60 C. Thin paraffin sections were deparaffinized with xylene, immersed in acetone and then phosphate buffered saline, and immunostained with various monoclonal and conventional antibodies, which have only been used on fresh-frozen or PLP-fixed frozen sections. As with PLP-fixed frozen sections, the following antigens were clearly demonstrated in the tissue sections processed with the present method: T (Leu-1, Leu-2a, Leu-3a, Leu-4, OKT3, OKT4, OKT8), B (B1, B2, Leu-14, IgM, IgD) lymphocyte surface markers and other antigens (Leu-7, OKT6, OKT9, OKM1, OKI1, J5, Ki-1, Ki-67, TdT, oncogene Ha-ras P21). Sections prepared by the present method demonstrated much better histologic and cytologic preservation than possible in frozen sections. 相似文献