全文获取类型
收费全文 | 9574篇 |
免费 | 445篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 105篇 |
儿科学 | 268篇 |
妇产科学 | 92篇 |
基础医学 | 1297篇 |
口腔科学 | 287篇 |
临床医学 | 679篇 |
内科学 | 2354篇 |
皮肤病学 | 267篇 |
神经病学 | 857篇 |
特种医学 | 251篇 |
外科学 | 1706篇 |
综合类 | 42篇 |
一般理论 | 1篇 |
预防医学 | 278篇 |
眼科学 | 164篇 |
药学 | 644篇 |
中国医学 | 19篇 |
肿瘤学 | 744篇 |
出版年
2023年 | 47篇 |
2022年 | 78篇 |
2021年 | 163篇 |
2020年 | 99篇 |
2019年 | 160篇 |
2018年 | 189篇 |
2017年 | 145篇 |
2016年 | 162篇 |
2015年 | 166篇 |
2014年 | 202篇 |
2013年 | 272篇 |
2012年 | 449篇 |
2011年 | 467篇 |
2010年 | 251篇 |
2009年 | 220篇 |
2008年 | 372篇 |
2007年 | 423篇 |
2006年 | 397篇 |
2005年 | 432篇 |
2004年 | 412篇 |
2003年 | 409篇 |
2002年 | 443篇 |
2001年 | 351篇 |
2000年 | 380篇 |
1999年 | 348篇 |
1998年 | 128篇 |
1997年 | 102篇 |
1996年 | 101篇 |
1995年 | 93篇 |
1994年 | 69篇 |
1993年 | 55篇 |
1992年 | 236篇 |
1991年 | 227篇 |
1990年 | 202篇 |
1989年 | 189篇 |
1988年 | 156篇 |
1987年 | 182篇 |
1986年 | 152篇 |
1985年 | 145篇 |
1984年 | 101篇 |
1983年 | 85篇 |
1979年 | 86篇 |
1978年 | 61篇 |
1977年 | 55篇 |
1971年 | 57篇 |
1970年 | 40篇 |
1969年 | 44篇 |
1968年 | 54篇 |
1967年 | 43篇 |
1966年 | 44篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
Hiroshi Kaneko Haruto Hj Shinobu Ishikawa Michio Kikuchi 《Pathology international》1977,27(3):375-385
A large tumor massively occupying the left pleural cavity had the Andings of both typical carcinoid and oncocytoma which were thought to be of bronchogenic origin. The ultrastructural observation of the tumor revealed a mixture of rod-shaped granules in addition to usual round neurosecretory ones. In the nuclei of dark cells of the oncocytoma, a latticed or hatched structure was detected. Besides two adenomas and hyperplastic foci of large acidophilic cells in the thyroid, a black adenoma and cortical adenoma in the adrenal gland, were detected. Moreover, there was an ectopic adrenal gland in the retroperitoneum. Briefly it was suggested that the bronchial carcinoid presented may be related to multiple endocrine adenomatosis. 相似文献
52.
The morphology of the equine allantochorion at the tip of the pregnant horn was studied in the membranes of 14 mares. The findings in the allantochorion at the tip of the pregnant horn were of two types; one was growth retardation (hypoplastic villi, tunica adventitia of the vessels resembling embryonal connective tissue and the extended spaces of remnants of the extraembryonic coelom), the other was placental hypoxia or ischaemia (parakeratosis, stratified squamous metaplasia, necrosis of the trophoblasts, thickening of the basement membrane and fibrous hyperplasia of villous stroma). It seems likely that hypoplastic villi are caused by disordered formation of the microcotyledon accompanying the progression of pregnancy. 相似文献
53.
54.
Amagai T Mouri T Kirii K Hori T Kaneko M Ohkawa H 《Clinical and experimental pharmacology & physiology. Supplement》2002,(29):S19-S22
1. Biliary atresia (BA), as a common disease in Japan, and cystic fibrosis (CF), as an extremely uncommon disease in Japan, were selected to assess the clinical significance of measurement of energy expenditure (EE). 2. Energy expenditure was significantly higher in children with BA than in normal children. 3. Measurement of EE in BA lead to clues to resolving its mechanism by novel assessment of interleukin-6 and leptin. 4. Energy expenditure in children with CF is also higher, but this has been addressed by nutritional intervention with additional calories. 5. Individualization of EE measurement is necessary in the analysis of pathological mechanisms and nutritional management of patients with both common and uncommon diseases. 相似文献
55.
Experimental induction of uterine cancer in rats by N-ethyl-N'-nitro-N-nitrosoguanidine dissolved in polyethylene glycol 总被引:2,自引:0,他引:2
H Ogino M Fujimoto H Oshiro K Matsumoto M Funahashi C Kaneko I Hirono 《Pathology, research and practice》1989,185(2):214-217
In the present experiment we attempted to experimentally induce uterine cancer in rats by injecting into the uterine cavity N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) dissolved in polyethylene glycol (PEG). Fifty-nine female F-344 rats, 7-8 weeks old, were divided into three groups and each received in the left uterine cavity with laparotomy a single dose of ENNG dissolved in PEG according to the following schedule: Group 1 received 75 mg ENNG/kg body wt.; Group 2 had 20 mg ENNG/kg body wt.: and Group 3 was given only PEG. In Group 1 it was observed that adenocarcinoma and sarcoma were present in the uterine corpus while squamous cell carcinoma occurred in the uterine cervix. In Group 2, although tumors such as adenocarcinoma, adenoma and sarcoma were observed in the uterine corpus, no tumor was present in the uterine cervix. No tumor growth whatsoever was observed in Group 3. From the above results it is apparent that the present method is an efficient means for experimentally inducing uterine cancer and that the site of tumor generation varies according to the concentration of ENNG administered. 相似文献
56.
57.
Yoshihito Osada Kayo Umezawa Aizo Yamauchi 《Macromolecular chemistry and physics.》1988,189(3):597-605
An artificial oscillating system consisting of water-swollen polyelectrolyte gels, to which a constant electric potential was applied, is described. It was found that repetitive oscillations occurred in three-dimensional crosslinked gels made of synthetic polyelectrolytes, proteins and of polysaccharides. The repetitive oscillations were rather stable regardless of the “stimulating” current density, and the frequency was of the order 0,01 to 0,2 Hz which gradually decreased with time. Power spectra and Lorentz plots were obtained and a semi-quantitative analysis of the oscillation was carried out. 相似文献
58.
Kang YS Yamazaki S Iyoda T Pack M Bruening SA Kim JY Takahara K Inaba K Steinman RM Park CG 《International immunology》2003,15(2):177-186
The marginal zone macrophages of the spleen are implicated in the clearance of polysaccharides, but underlying mechanisms need to be pinpointed. SIGN-R1 is one of five recently identified mouse genes that are homologous to human DC-SIGN and encode a single, external, C-terminal C-type lectin domain. We find that a polyclonal antibody to a specific SIGN-R1 peptide reacts primarily and strongly with a subset of macrophages in the marginal zone of spleen and lymph node medulla. In both sites, SIGN-R1 exists primarily in an aggregated form, resistant to dissociation into monomers upon boiling in SDS under reducing conditions. Upon transfection into three different cell lines, high-mol.-wt forms bearing SIGN-R1 are expressed, as well as reactivity with ER-TR9, a mAb previously described to react selectively with marginal zone macrophages. SIGN-R1-expressing macrophages preferentially sequester dextrans following i.v. injection. Likewise, when phagocytic cells are enriched from spleen and tested in culture, dextran is selectively endocytosed by a subset of very large SIGN-R1(+) cells representing approximately 5% of total released macrophages. Uptake of FITC-dextran by these macrophages in vivo and in vitro is blocked by ER-TR9 and polyclonal anti-SIGN-R1 antibodies. Following transfection with SIGN-R1, cell lines become competent to endocytose dextrans. The dextran localizes primarily to compartments lacking transferrin receptor and the LAMP-1 CD107a panlysosomal antigen. Therefore, SIGN-R1 mediates the uptake of dextran polysaccharides, and it is predominantly expressed in the macrophages of the splenic marginal zone and lymph node medulla. 相似文献
59.
60.
Immune Abnormalities Induced by Human Endogenous Retroviral Peptides: With Reference to the Pathogenesis of Systemic Lupus Erythematosus 总被引:1,自引:0,他引:1
Naito T Ogasawara H Kaneko H Hishikawa T Sekigawa I Hashimoto H Maruyama N 《Journal of clinical immunology》2003,23(5):371-376
P15E is a specific sequence among the envelope gene (env)-encoded transmembrane proteins of exogenous and endogenous retroviruses. A synthetic peptide (CKS-17) that shows homology to this p15E region in several species of retrovirus is known to induce immune abnormalities. In this study, we examined the effect of a synthetic peptide derived from a region of human endogenous retrovirus (HERV) clone 4-1 ( 4-1) similar to sequences of CKS-17 on the induction of systemic lupus erythematosus (SLE)-related immune abnormalities. Our results indicated that this peptide could induce T-cell activation and anergy in normal peripheral blood mononuclear cells, and the peptide could also promote the production of interleukins IL-6 and IL-16. These phenomena are representative immune abnormalities observed in SLE patients. Thus, our findings support the possibility that HERV acts as a pathogen in human SLE. 相似文献