全文获取类型
收费全文 | 8257篇 |
免费 | 497篇 |
国内免费 | 61篇 |
专业分类
耳鼻咽喉 | 68篇 |
儿科学 | 160篇 |
妇产科学 | 125篇 |
基础医学 | 1197篇 |
口腔科学 | 204篇 |
临床医学 | 505篇 |
内科学 | 2214篇 |
皮肤病学 | 151篇 |
神经病学 | 670篇 |
特种医学 | 329篇 |
外科学 | 1177篇 |
综合类 | 43篇 |
一般理论 | 3篇 |
预防医学 | 368篇 |
眼科学 | 161篇 |
药学 | 627篇 |
中国医学 | 20篇 |
肿瘤学 | 793篇 |
出版年
2023年 | 68篇 |
2022年 | 167篇 |
2021年 | 237篇 |
2020年 | 150篇 |
2019年 | 169篇 |
2018年 | 212篇 |
2017年 | 151篇 |
2016年 | 174篇 |
2015年 | 241篇 |
2014年 | 276篇 |
2013年 | 299篇 |
2012年 | 510篇 |
2011年 | 493篇 |
2010年 | 285篇 |
2009年 | 259篇 |
2008年 | 443篇 |
2007年 | 392篇 |
2006年 | 415篇 |
2005年 | 410篇 |
2004年 | 389篇 |
2003年 | 346篇 |
2002年 | 358篇 |
2001年 | 226篇 |
2000年 | 221篇 |
1999年 | 208篇 |
1998年 | 93篇 |
1997年 | 88篇 |
1996年 | 65篇 |
1995年 | 46篇 |
1994年 | 41篇 |
1993年 | 38篇 |
1992年 | 137篇 |
1991年 | 127篇 |
1990年 | 106篇 |
1989年 | 124篇 |
1988年 | 80篇 |
1987年 | 75篇 |
1986年 | 80篇 |
1985年 | 76篇 |
1984年 | 68篇 |
1983年 | 52篇 |
1982年 | 24篇 |
1979年 | 51篇 |
1978年 | 25篇 |
1977年 | 31篇 |
1976年 | 24篇 |
1974年 | 26篇 |
1971年 | 25篇 |
1970年 | 25篇 |
1967年 | 23篇 |
排序方式: 共有8815条查询结果,搜索用时 15 毫秒
81.
Takeshi Hariya Yuusuke Kobayashi Michiko Aihara Mamiko Ishiwa Michio Shibata Hideyuki Ichikawa Zenro Ikezawa 《Arerugī》2002,51(11):1113-1122
Atopic dermatitis (AD) has been clinically well-known to be frequently exacerbated by psychological and physiological stress. In this study, we examined effects of sedative odorant (modified valerian oil) inhalation on patients with AD. We investigated clinical scores, skin physiological parameters and psychological questionnaire (POMS) every 2 weeks. For first 2 weeks, we arranged non-inhalation period. Results for non-inhalation period were compared with these of 2- or 4-week inhalation. As results, sum of skin clinical scores significantly improved after odorant inhalation. Some patients improved for non-inhalation period, too. However, patients that had not improved for non-inhalation period significantly improved after odorant inhalation. Skin conductance and skin dryness/scaling score also improved after odorant inhalation without improving for non-inhalation period. Psychological parameter (POMS) also tended to improve after odorant inhalation. These results suggest that sedative odorants may be useful as a complementary therapy for AD through psychosomatic stress care. 相似文献
82.
Victor A. Sorokin Vladimir F. Fedorov Victor S. Leontiev Yuri P. Blagoi Vladimir L. Galkin 《Macromolecular chemistry and physics.》1987,188(10):2301-2309
The helix-coil transition in Phage T2 DNA in the presence of 6,4 · 10?3 mol/l Mn2+ is studied using light scattering and UV spectroscopy. The transition range is about 0,5°C. Near the temperature of the end of melting Tf the molecular weight Mw and the radius of gyration Rz of the complex are observed to decrease to about one half. At a temperature 0,1–0,25°C higher than Tf, Mw and Rz pass through a minimum, which implies that aggregation is preceded by unwinding of DNA strands. Thus, rise in temperature rather than Mn2+ -induced aggregation causes DNA + Mn2+ melting. 相似文献
83.
Monoclonal antibodies to monkey brain choline acetyltransferase: production and immunohistochemistry 总被引:1,自引:0,他引:1
Two monoclonal antibodies to monkey brain choline acetyltransferase (ChAT) were obtained. Immunoblot analysis indicated that both antibodies revealed two adjacent protein bands on a sodium dodecyl sulfate-polyacrylamide gel electrophoresis. ChAT was demonstrated immunohistochemically by one of the antibodies in the motoneurons in the monkey brainstem and spinal cord. This antibody also revealed ChAT-positive terminal-like structures in the neuropils of lamina IX of the cervical spinal cord and interpeduncular nucleus. 相似文献
84.
Deepika D'Cunha Burkardt Anna Zachariou Chey Loveday Clare L. Allen David J. Amor Anna Ardissone Siddharth Banka Alexia Bourgois Christine Coubes Cheryl Cytrynbaum Laurence Faivre Gerard Marion Rachel Horton Dieter Kotzot Guillermo Lay‐Son Melissa Lees Karen Low Ho‐Ming Luk Paul Mark Allyn McConkie‐Rosell Marie McDonald John Pappas Christophe Phillipe Deborah Shears Brian Skotko Fiona Stewart Helen Stewart I Karen. Temple Frederic T. Mau‐Them Ricardo A. Verdugo Rosanna Weksberg Yuri A. Zarate John M. Graham Katrina Tatton‐Brown 《American journal of medical genetics. Part A》2019,179(10):2049-2055
85.
Kunikata T Yamane H Segi E Matsuoka T Sugimoto Y Tanaka S Tanaka H Nagai H Ichikawa A Narumiya S 《Nature immunology》2005,6(5):524-531
Prostaglandins, including PGD(2) and PGE(2), are produced during allergic reactions. Although PGD(2) is an important mediator of allergic responses, aspirin-like drugs that inhibit prostaglandin synthesis are generally ineffective in allergic disorders, suggesting that another prostaglandin-mediated pathway prevents the development of allergic reactions. Here we show that such a pathway may be mediated by PGE(2) acting at the prostaglandin E receptor EP3. Mice lacking EP3 developed allergic inflammation that was much more pronounced than that in wild-type mice or mice deficient in other prostaglandin E receptor subtypes. Conversely, an EP3-selective agonist suppressed the inflammation. This suppression was effective when the agonist was administered 3 h after antigen challenge and was associated with inhibition of allergy-related gene expression. Thus, the PGE(2)-EP3 pathway is an important negative modulator of allergic reactions. 相似文献
86.
Localizations of J-chain-positive cells (JPC) were examined in chicken lymphatic tissues before and after hatching. The cells containing J chain were first detected in medullary areas of the bursa of FABRICIUS during the embryonic stage. These positive cells were partly detected in the developing small lymphatic follicles: perhaps on newly differentiating precursor B-cells. In addition to these lymphatic follicles, connective tissue of bursal fold were also detected as J-chain positive. Although similar localizations of JPC were again observed in hatched chickens, positive areas of follicular medulla were strongly stained for fluorescence with corresponding antisera than that of embryonic ones. These data may reflect differences in the physiology of lymphocytes in respect to functional development. JPC localizations were next compared between the B-cell subpopulations, mu-(microPC) and alpha-chain-positive cells (alpha PC). The J-chains detectable in the IgM molecules were also found in follicular medulla. However, these follicles were almost found to be negative for J-chains detectable in the alpha PC before hatching. Any strong stainings for J-chain in the alpha PC were, moreover, not be observed in bursa after hatching. The microPC localizations in hatched chickens were roughly equal with the pattern of JPC localization. These analyses revealed the presence of the cells having the chains of both mu and J. The results together with other recent studies further shown that bursal J-chain can be partly detected in newly differentiated lymphatic follicles lacking IgM-producing and suggest the possible presence of B-cell-differentiation sequence of Ig-J+----IgM+J+----IgA+J+. 相似文献
87.
Despite a multitude of reports on the classification and distribution of anterior pituitary cells, no previous study has attempted to obtain the three-dimensional (3D) and computer-graphic distribution pattern of each cell type in the whole pituitary. Therefore, we mapped the anterior pituitary cells of the house musk shrew ( Suncus murinus) and found a distinct cellular distribution pattern. Serial horizontal sections of whole shrew pituitaries were stained immunohistochemically for prolactin (PRL), growth hormone (GH), and adrenocorticotropic hormone (ACTH) cells. The contours of positive cells and the anterior, intermediate, and posterior lobes in each section were digitized for 3D visualization by a volume rendering method. The reconstructed images and virtual frontal and sagittal slices were examined in detail. On the 3D reconstructed images, the PRL and GH cells had similar distribution patterns, although the former were concentrated in the dorsolateral and ventrocentral portions, and the latter in the dorsocentral portions of the anterior lobe. On both sides of the pituitary stalk, there lay portions that were conspicuous by scarcity of PRL and GH cells. ACTH cells were widely scattered throughout the whole anterior lobe, but they were very few in the above portions and the dorsocentral portions where GH cells were concentrated. No sex difference in the distribution patterns of each cell type was observed. However, PRL cells in females were more numerous than in males, whereas the opposite was true for GH and ACTH cells. We discuss the relationship between the formation of the spatial distribution patterns and anterior pituitary ontogeny. 相似文献
88.
Kasahara K Taguchi T Yamasaki I Kamada M Yuri K Shuin T 《Cancer Genetics and Cytogenetics》2002,137(1):59-63
In this study, we examined nine cases of advanced Japanese prostate cancer by comparative genomic hybridization (CGH) to detect chromosomal imbalances across the entire genome and to identify several new regions likely to contain genes important to the development and progression of this disease. These cases had been previously examined for numerical chromosomal aberrations by fluorescence in situ hybridization (FISH). By CGH, the following regions were found to be over-represented (gains), with fluorescence ratio values higher than the threshold: 4p, 6p, 8q, 11q, 12q, 15q, 16p, 17q, 20, and 21 (>4 cases); underrepresentation (losses) involved: 1q, 4q, 5q, 6q, 13q, 14q, and 22 (>4 cases). The shortest regions of overlap (SRO) of gains were noted at 8q24.1 through q24.3, 12q23, and 17q23 through q24 (>5 cases). The SRO of losses were seen at 5q14 through q21, 6q16.1 through q21, 13q21.3 through q22, and 14q21 (>5 cases). Notably, the gain of chromosomes 8 and 12 by CGH was in agreement with the FISH data, suggesting that the gain of chromosomes 8 and 12 may play an important role in prostate carcinogenesis. The genes on the SRO regions were also discussed in relation to oncogenes and bone metastases. 相似文献
89.
Wada Takehiko Ishimoto Takuji Nakaya Izaya Kawaguchi Takehiko Sofue Tadashi Shimizu Sayaka Kurita Noriaki Sasaki Sho Nishiwaki Hiroki Koizumi Masahiro Saito Shoji Nishibori Nobuhiro Oe Yuji Yoshida Mai Miyaoka Yoshitaka Akiyama Shin’ichi Itano Yuya Okazaki Masaki Ozeki Takaya Ichikawa Daisuke Oguchi Hideyo Kohsaka Satoshi Kosaka Shiho Kataoka Yuki Shima Hideaki Shirai Sayuri Sugiyama Kazuhiro Suzuki Tomo Son Daisuke Tanaka Tomomi Nango Eishu Niihata Kakuya Nishijima Yoko Nozu Kandai Hasegawa Midori Miyata Rei Yazawa Masahiko Yamamoto Yoshihiro Yamamoto Ryohei Shibagaki Yugo Furuichi Kengo Okada Hirokazu Narita Ichiei 《Clinical and experimental nephrology》2021,25(12):1277-1285
Clinical and Experimental Nephrology - 相似文献
90.
Nishida Hayato Fukuhara Hiroki Nawano Takaaki Kanno Hidenori Yagi Mayu Yamagishi Atsushi Sakurai Toshihiko Naito Sei Kato Tomoyuki Kudo Kosuke Ichikawa Kazunobu Tsuchiya Norihiko 《Clinical and experimental nephrology》2021,25(12):1346-1353
Clinical and Experimental Nephrology - Arteriovenous fistula (AVF) is the most preferred vascular access for hemodialysis patients, and early failure of AVF is one of the most avoidable... 相似文献