全文获取类型
收费全文 | 12273篇 |
免费 | 613篇 |
国内免费 | 100篇 |
专业分类
耳鼻咽喉 | 67篇 |
儿科学 | 239篇 |
妇产科学 | 168篇 |
基础医学 | 1754篇 |
口腔科学 | 310篇 |
临床医学 | 755篇 |
内科学 | 2970篇 |
皮肤病学 | 319篇 |
神经病学 | 930篇 |
特种医学 | 480篇 |
外科学 | 1896篇 |
综合类 | 38篇 |
预防医学 | 409篇 |
眼科学 | 133篇 |
药学 | 943篇 |
中国医学 | 34篇 |
肿瘤学 | 1541篇 |
出版年
2023年 | 46篇 |
2022年 | 76篇 |
2021年 | 230篇 |
2020年 | 127篇 |
2019年 | 156篇 |
2018年 | 232篇 |
2017年 | 223篇 |
2016年 | 246篇 |
2015年 | 247篇 |
2014年 | 337篇 |
2013年 | 414篇 |
2012年 | 655篇 |
2011年 | 780篇 |
2010年 | 440篇 |
2009年 | 366篇 |
2008年 | 613篇 |
2007年 | 726篇 |
2006年 | 748篇 |
2005年 | 719篇 |
2004年 | 694篇 |
2003年 | 691篇 |
2002年 | 656篇 |
2001年 | 267篇 |
2000年 | 248篇 |
1999年 | 261篇 |
1998年 | 209篇 |
1997年 | 136篇 |
1996年 | 120篇 |
1995年 | 118篇 |
1994年 | 102篇 |
1993年 | 89篇 |
1992年 | 166篇 |
1991年 | 162篇 |
1990年 | 168篇 |
1989年 | 181篇 |
1988年 | 159篇 |
1987年 | 153篇 |
1986年 | 153篇 |
1985年 | 140篇 |
1984年 | 81篇 |
1983年 | 75篇 |
1982年 | 48篇 |
1981年 | 32篇 |
1980年 | 37篇 |
1979年 | 53篇 |
1978年 | 42篇 |
1977年 | 34篇 |
1975年 | 31篇 |
1974年 | 40篇 |
1969年 | 32篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Fibronectin binds to C1q: possible mechanisms for their co-precipitation in cryoglobulins from patients with systemic lupus erythematosus
下载免费PDF全文
![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
I Kono T Sakurai T Kabashima K Yamane H Kashiwagi 《Clinical and experimental immunology》1983,52(2):305-310
Fibronectin and C1q frequently co-precipitated in cryoglobulins from patients with SLE. As a portion of the C1q molecule is similar to collagen to which fibronectin has a high affinity, we studied whether fibronectin specifically bound to C1q. Fibronectin was found to bind to both native and heat-inactivated C1q. The binding was enhanced by Ca++ and low ionic strength. We have also demonstrated that fibronectin is capable of binding to C1q fixed to immune complexes. The interaction between fibronectin and C1q may play a role in cryoglobulin formation and in clearance of immune complexes by reticuloendothelial system. 相似文献
102.
103.
K Hashizume K Ichikawa A Sakurai S Suzuki T Takeda M Kobayashi T Miyamoto M Arai T Nagasawa 《The New England journal of medicine》1991,324(14):947-953
BACKGROUND. Antibodies to thyroid-stimulating hormone (TSH) receptors that stimulate the thyroid gland cause hyperthyroidism in patients with Graves' disease, and their production during antithyroid drug treatment is an important determinant of the course of the disease. One factor that might contribute to the persistent production of antibodies to TSH receptors is stimulation of the release of thyroid antigens by TSH during antithyroid drug therapy. We therefore studied the effect of the suppression of TSH secretion by thyroxine on the levels of antibodies to TSH receptors after thyroid hormone secretion had been normalized by methimazole. METHODS AND RESULTS. The levels of antibodies to TSH receptors were measured during treatment with methimazole, either alone or in combination with thyroxine, in 109 patients with hyperthyroidism due to Graves' disease. The patients first received 30 mg of methimazole daily for six months. All were euthyroid after six months, and their mean (+/- SD) level of antibodies to TSH receptors decreased from 64 +/- 9 percent to 25 +/- 15 percent (P less than 0.01; normal, 2.9 +/- 1.4 percent). Sixty patients then received 100 micrograms of thyroxine and 10 mg of methimazole and 49 received placebo and 10 mg of methimazole daily for one year. In the thyroxine-treated group, the mean serum thyroxine concentration increased from 108 +/- 16 nmol per liter to 145 +/- 11 nmol per liter (P less than 0.01), and the level of antibodies to TSH receptors decreased from 28 +/- 10 percent to 10 +/- 3 percent after one month of combination therapy. In the patients who received placebo and methimazole, the mean serum thyroxine concentration decreased and the level of antibodies to TSH receptors did not change. Methimazole, but not thyroxine or placebo, was discontinued in each group 1 1/2 years after the beginning of treatment. The level of antibodies to TSH receptors further decreased (from 6.6 +/- 3.2 percent at the time methimazole was discontinued to 2.1 +/- 1.2 percent one year later) in the patients who continued to receive thyroxine, but it increased (from 9.1 +/- 4.8 percent to 17.3 +/- 5.8 percent during the same period) in the patients who received placebo. One patient in the thyroxine-treated group (1.7 percent) and 17 patients in the placebo group (34.7 percent) had recurrences of hyperthyroidism within three years after the discontinuation of methimazole. CONCLUSIONS. The administration of thyroxine during antithyroid drug treatment decreases both the production of antibodies to TSH receptors and the frequency of recurrence of hyperthyroidism. 相似文献
104.
Two closely related ubiquitin C-terminal hydrolase isozymes function as reciprocal modulators of germ cell apoptosis in cryptorchid testis
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)
Kwon J Wang YL Setsuie R Sekiguchi S Sato Y Sakurai M Noda M Aoki S Yoshikawa Y Wada K 《The American journal of pathology》2004,165(4):1367-1374
The experimentally induced cryptorchid mouse model is useful for elucidating the in vivo molecular mechanism of germ cell apoptosis. Apoptosis, in general, is thought to be partly regulated by the ubiquitin-proteasome system. Here, we analyzed the function of two closely related members of the ubiquitin C-terminal hydrolase (UCH) family in testicular germ cell apoptosis experimentally induced by cryptorchidism. The two enzymes, UCH-L1 and UCH-L3, deubiquitinate ubiquitin-protein conjugates and control the cellular balance of ubiquitin. The testes of gracile axonal dystrophy (gad) mice, which lack UCH-L1, were resistant to cryptorchid stress-related injury and had reduced ubiquitin levels. The level of both anti-apoptotic (Bcl-2 family and XIAP) and prosurvival (pCREB and BDNF) proteins was significantly higher in gad mice after cryptorchid stress. In contrast, Uchl3 knockout mice showed profound testicular atrophy and apoptotic germ cell loss after cryptorchid injury. Ubiquitin level was not significantly different between wild-type and Uchl3 knockout mice, whereas the levels of Nedd8 and the apoptotic proteins p53, Bax, and caspase3 were elevated in Uchl3 knockout mice. These results demonstrate that UCH-L1 and UCH-L3 function differentially to regulate the cellular levels of anti-apoptotic, prosurvival, and apoptotic proteins during testicular germ cell apoptosis. 相似文献
105.
Kazuko Sukegawa Shunji Tomatsu Toshiyuki Fukao Hideki Iwata Xiang-Qian Song Yukiji Yamada Seiji Fukuda Kouji Isogai Tadao Orii 《Human mutation》1995,6(2):136-143
Mucopolysaccharidosis type II (Hunter disease) is a lysosomal storage disorder caused by a deficiency of the enzyme iduronate-2-sulfatase. Varied clinical phenotypes of this disease have been described. To identify mutations in individual patients and to examine possible correlations between mutations and clinical phenotypes, we analyzed the iduronate-2-sulfatase gene in Japanese patients with different clinical phenotypes. Five missense mutations, S333L (severe), R468Q (severe), R468L (severe), W337R (intermediate), R48P (mild), and three nonsense mutations, W345X (severe), R443X (intermediate), Q531X (mild), were identified by the RT-PCR method. Transient expression in the enzyme-deficient fibroblasts revealed that all five missense mutant enzymes were synthesized as the normal-size precursor (73 kD), and the nonsense mutant enzymes were synthesized as truncated ones (W345X:54 kD, R443X:59 kD, and Q531X:69 kD), although stable mature enzymes (45–56 kD) were not detected by Western blot analysis. Further more, expression of the eight mutant cDNAs resulted in severe reductions of iduronate-2-sulfatase enzyme activity in comparison with a normal cDNA. © 1995 Wiley-Liss, Inc. 相似文献
106.
Shigetoshi Horiguchi Yoshitaka Okamoto Shuji Yonekura Toru Okawa Naoki Kunii Heizaburo Yamamoto Daiju Sakurai Toyoyuki Hanazawa 《Arerugī》2008,57(5):558-561
BACKGROUND: Japanese cedar and cypress pollen share a common antigen. The cedar pollen season is followed by the cypress pollen season. However, both the clinical significance and involvement of cypress pollinosis in the treatment of the cedar pollinosis have not yet been clarified. METHODS: The clinical efficacy of sublingual immunotherapy with cedar pollen extract for cedar pollinosis was evaluated during the cypress pollen dispersal season in Japan. In addition, the change in cypress pollen specific IgE antibodies of the patients with cedar pollinosis was examined before and after the pollen season. RESULTS: Sublingual immunotherapy with cedar pollen extract did not improve the clinical symptoms of the cedar pollinosis patients combined with cypress pollinosis in the cypress pollen season. The cypress pollen specific IgE antibodies were found to demonstrate significant seasonal changes. CONCLUSION: The presence of cypress pollinosis should therefore be taken into consideration when planning the optimal treatment for cedar pollinosis. Sublingual immunotherapy with cedar pollen extract may not be effective for cypress pollinosis. 相似文献
107.
Yoshida A Miyaura M Sakurai A Fukumori T Fujita M Akari H Adachi A 《International journal of molecular medicine》2000,6(1):83-86
The expression level of major histocompatibility class I (MHC-I) and the extent of down-regulation of MHC-I after an anti-MHC-I antibody treatment in numerous human T-cell leukemia virus type 1 (HTLV-1)-positive and -negative lymphocytic cell lines were examined. While there was no clear correlation between the expression level of MHC-I and the presence of HTLV-1 genome, a relatively low level of MHC-I down-regulation was generally induced in HTLV-1-positive cells by the antibody. The results may suggest the potential involvement of MHC-I in HTLV-1 leukemogenesis. 相似文献
108.
109.
Haruyo Nakajima PhDa Satoshi Hachimuraa Shinya Nishiwakia Toshiyuki Katsuki MD PhDb Naoki Shimojo MD PhDb Akio Ametani PhDa Yoichi Kohno MD PhDb Shuichi Kaminogawa PhDa 《The Journal of allergy and clinical immunology》1996,97(6):1342-1349
To study cow’s milk allergy at the cellular level, we assessed the reactivity of peripheral blood mononuclear cells from patients allergic to cow’s milk to αs1-casein, which is one of the major allergens in cow’s milk. Proliferation of the cells to αs1-casein activation showed a rather weak response. Therefore to understand T-cell reactivity to αs1-casein in more detail, we prepared αs1-casein–specific T-cell lines from patients allergic to cow’s milk and established 26 T-cell lines. These T-cell lines could be classified into three groups by analyzing their surface marker expression: those containing predominantly CD4+CD8- T cells, those containing both CD4+CD8- and CD4-CD8+ T cells, and those containing predominantly CD4-CD8+ T cells. The CD8+ T cells were obtained at an unexpectedly higher frequency from the patients. These T-cell lines produced interferon-γ and IL-4. These results suggest that CD8+ T cells specific for αs1-casein and CD4+ T cells were primed by the stimulation with αs1-casein in patients allergic to milk and that both T cells may play a key role in the onset, progression of, or recovery from cow’s milk allergy. (J ALLERGY CLIN IMMUNOL 1996;97:1342-9.) 相似文献
110.
Toshio Morohoshi Fumiaki Sagawa Toshiyuki Mitsuya 《Virchows Archiv : an international journal of pathology》1990,416(3):265-270
Summary The autopsy findings in a pancreatoblastoma in a 7-year-old Japanese girl is reported. The tumour was in the head and body of the pancreas, and was associated with diffuse carcinomatous peritonitis and hepatic and pulmonary metastases. There was marked elevation (more than 10000 ng/ml) of serum alpha-fetoprotein (AFP). Histopathologically the tumour was composed of solid epithelial elements with fibrous stroma, showing acinar arrangement, squamoid clusters and tubular structures. The epithelial elements contained numerous fine PAS positive granules in the cytoplasm. Immunocytochemical results suggested epithelial differentiation with positivity to alpha-1-antitrypsin (AAT), keratin, CA19-9, and AFP. No endocrine elements were recognized. Characteristic feature of this tumour are discussed and compared with prevoius reports. 相似文献