全文获取类型
收费全文 | 5554篇 |
免费 | 239篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 89篇 |
儿科学 | 93篇 |
妇产科学 | 26篇 |
基础医学 | 648篇 |
口腔科学 | 71篇 |
临床医学 | 332篇 |
内科学 | 1312篇 |
皮肤病学 | 127篇 |
神经病学 | 372篇 |
特种医学 | 124篇 |
外科学 | 1178篇 |
综合类 | 19篇 |
预防医学 | 170篇 |
眼科学 | 193篇 |
药学 | 415篇 |
中国医学 | 1篇 |
肿瘤学 | 636篇 |
出版年
2022年 | 52篇 |
2021年 | 53篇 |
2020年 | 40篇 |
2019年 | 55篇 |
2018年 | 80篇 |
2017年 | 73篇 |
2016年 | 89篇 |
2015年 | 107篇 |
2014年 | 133篇 |
2013年 | 152篇 |
2012年 | 213篇 |
2011年 | 260篇 |
2010年 | 161篇 |
2009年 | 125篇 |
2008年 | 219篇 |
2007年 | 238篇 |
2006年 | 265篇 |
2005年 | 274篇 |
2004年 | 250篇 |
2003年 | 252篇 |
2002年 | 272篇 |
2001年 | 199篇 |
2000年 | 220篇 |
1999年 | 206篇 |
1998年 | 61篇 |
1997年 | 63篇 |
1996年 | 47篇 |
1995年 | 54篇 |
1994年 | 52篇 |
1993年 | 44篇 |
1992年 | 142篇 |
1991年 | 127篇 |
1990年 | 115篇 |
1989年 | 104篇 |
1988年 | 115篇 |
1987年 | 89篇 |
1986年 | 102篇 |
1985年 | 108篇 |
1984年 | 56篇 |
1983年 | 50篇 |
1982年 | 34篇 |
1979年 | 39篇 |
1977年 | 34篇 |
1974年 | 28篇 |
1973年 | 27篇 |
1972年 | 28篇 |
1970年 | 26篇 |
1969年 | 27篇 |
1967年 | 33篇 |
1966年 | 27篇 |
排序方式: 共有5806条查询结果,搜索用时 15 毫秒
71.
Culture of chondrocytes in fibroin-hydrogel sponge 总被引:5,自引:0,他引:5
Aoki H Tomita N Morita Y Hattori K Harada Y Sonobe M Wakitani S Tamada Y 《Bio-medical materials and engineering》2003,13(4):309-316
Fibroin-hydrogel sponge and collagen gel were used as scaffold for in vitro cartilage regeneration. Fibroin-hydrogel sponge was formed by phase separation from freezed fibroin solution. Chondrocytes were harvested from proximal humerus, distal femur and proximal tibia of 4-week-old Japanese white rabbits and inoculated in the fibroin-hydrogel sponge and collagen gel. Those constructs were cultured in DMEM supplemented with 10% FCS and 50 ml L-ascorbate at 37 degrees C. Histological observation, measurement of sulfated glycosaminoglycan and cell density were carried out at 3, 7, and 14 days after the cultivation. Well-defined cartilage tissue can be seen both in the fibroin-hydrogel sponge and in the collagen gel. The matrix was intensely stained by safranin-O and showed a metachromatic reaction in both group. However, the quantity of sulfated glycosaminoglycan and cell density of the fibroin-hydrogel sponge group were increased more rapidly than these of the collagen gel group. Thus, the chondrocytes proliferated in the fibroin sponge without losing their differentiated phenotype. It is possible that culture environment in the fibroin sponge was suitable for chondrocytes regeneration. 相似文献
72.
An autosomal dominant posterior polar cataract locus maps to human chromosome 20p12-q12 总被引:4,自引:0,他引:4
Yamada K Tomita H Yoshiura K Kondo S Wakui K Fukushima Y Ikegawa S Nakamura Y Amemiya T Niikawa N 《European journal of human genetics : EJHG》2000,8(7):535-539
We assigned the locus for a previously reported new type of autosomal dominant posterior polar cataract (CPP3) to 20p12-q12 by a genome-wide two-point linkage analysis with microsatellite markers. CPP3 is characterized by progressive, disc-shaped, posterior subcapsular opacity. The disease was seen in 10 members of a Japanese family and transmitted in an autosomal dominant fashion through four generations. We obtained a maximum lod score (Zmax) of 3.61 with a recombination fraction (theta) of 0.00 for markers D20S917, D20S885 and D20S874. Haplotype analysis gave the disease gene localization at a 15.7-cM interval between D20S851 and D20S96 loci on chromosome 20p12-q12. Since the BFSP1 that encodes the lens-specific beaded filament structural protein 1 (filensin) has been mapped around the CPP3 region, we performed sequence analysis on its entire coding region. However, no base substitution or deletion was detected in the CPP3 patients. The mapping of the CPP3 locus to 20p12-q12 not only expands our understanding of the genetic heterogeneity in autosomal dominant posterior polar cataracts but also is a clue for the positional cloning of the disease gene. 相似文献
73.
74.
Rabbit factor P, which is involved in stabilizing the labile C3 convertase of the alternative complement pathway, was isolated from rabbit serum by a simple two-step procedure: polyethylene glycol precipitation and QAE-Sephadex A-50 column chromatography. The chemical properties, and functional activities of the rabbit P were very similar to those of human P, except that there were slight differences in the SDS-PAGE patterns of limited tryptic digests and in the amino terminal sequences. The molecular weights were estimated to be 58 000 for rabbit P and 59 000 for human P on SDS-PAGE under reducing conditions. The amino terminal 36 residues of rabbit P showed 78% homology to the equivalent region of human P. 相似文献
75.
Body-oriented therapies as relaxation training and certain forms of meditation are gaining popularity in the treatment and prevention of psychosomatic disorders. In this paper, a new method of self-control called self-regulation method (SRM), derived from autogenic training and Zen meditation, is presented. The technique of SRM is introduced. Secondly, physiological studies on SRM using skin temperature, galvanic skin response, and cortical evoked potentials are presented. Thirdly, the results of psychological tests conducted on SRM are presented. These psycho-physiological studies suggest that SRM may elicit a state of 'relaxed alertness'. Fourthly, clinical applications of SRM are discussed, and 3 cases are presented. Finally, SRM is discussed in relation to the psychology and physiology of 'relaxed alertness'. 相似文献
76.
Kuniaki Tanaka Yoshifumi Tomita Mari Tsuruta Fumiko Konishi Masao Okuda Kunisuke Himeno Kikuo Nomoto 《Immunopharmacology and immunotoxicology》1990,12(2):277-291
Chlorella vulgaris, an unicellular green algae, or its acetone-extract (Ac-Ex) were administered orally to Meth A tumor bearing BALB/c or (BALB/c DBA/2)F1 (CDF1) mice. When CDF1 mice were fed daily with 10% dried powder of Chlorella vulgaris (CVP) containing diet before and after Meth A tumor inoculation, the growth of rechallenged Meth A tumor was significantly suppressed in an antigen-specific manner. Augmentation of antitumor resistance was exhibited also by Winn assay using lymph node cells of tumor-bearing mice orally administered with CVP or Ac-Ex. Antigen-specific concomitant immunity in these mice were mediated by cytostatic T cells but not by cytotoxic T cells. Natural killer cells seemed not to contribute in antitumor resistance in this system. 相似文献
77.
Use of sulfonated probes for in situ detection of amylase mRNA in formalin-fixed paraffin sections of human pancreas and submaxillary gland 总被引:2,自引:0,他引:2
H Morimoto T Monden T Shimano M Higashiyama N Tomita M Murotani N Matsuura H Okuda T Mori 《Laboratory investigation; a journal of technical methods and pathology》1987,57(6):737-741
A sulfonated probe and its applicability to in situ hybridization is described and discussed. The DNA probes were modified by introducing an antigenic sulfone group into the cytidine residues of the denatured DNA (Budowsky EI, Sverdlov ED, Monastyrkaya GS: New method of selective and rapid modification of the cytidine residues. FEBS Lett 25:201, 1972). Hybridization of the sulfonated DNA with the target nucleic acid sequences was confirmed by an avidin-biotin peroxidase complex method using a monoclonal antibody specific to sulfonated DNA. The detection limit of this system was estimated to be about 1.25 pg of actual target sequences by dot blot hybridization analysis. When the sulfonated probes of human amylase cDNA were applied to in situ hybridization immunohistochemistry on formalin-fixed paraffin sections of the human pancreas and submaxillary gland, hybridization signals were clearly localized in the cytoplasm of the acinar cells of the pancreas, and in the serous cells of the submaxillary gland. Suitable probe lengths for in situ hybridization immunohistochemistry were between 100 and 800 bases. The in situ hybridization technique utilizing a sulfonated DNA probe is sensitive, simple, and easy to perform and applicable to studies of cell biology. 相似文献
78.
79.
BACKGROUND: Our aims were to follow the longitudinal changes in lumbar spine bone mineral density (BMD) with multiple pregnancies, and to study whether polymorphisms in the vitamin D receptor (VDR) and estrogen receptor (ER) genes may influence the results. METHODS: We repeatedly measured the BMD of the lumbar spine (L2-L4) of 133 women who had undergone two successive pregnancies and 73 non-pregnant controls, and analysed the restriction fragment length polymorphisms using restriction endonucleases TaqI, ApaI and FokI for the VDR gene, and PvuII and XbaI for the ER gene. RESULTS: Cases and controls had no significant differences in the longitudinal BMD changes. The mean percentage change in lumbar BMD (DeltaBMD%) of the women with the XX/Xx genotype was significantly lower than that of the women with the xx genotype after adjusting for age at each delivery, BMD of the first scan, and interval between the scans (0.2 +/- 3.3 versus 2.0 +/- 4.2%; P=0.030, analysis of covariance). Multiple regression analyses to evaluate the contribution of the XbaI polymorphism of the ER gene on DeltaBMD% showed that the percentage decrease in BMD was greater for women lacking the XbaI restriction site (adjusted R2=0.188, P<0.0001). CONCLUSIONS: The present study suggests that the DeltaBMD% was significantly influenced by the XbaI polymorphism of the ER gene. 相似文献
80.