全文获取类型
收费全文 | 2531篇 |
免费 | 213篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 84篇 |
妇产科学 | 48篇 |
基础医学 | 335篇 |
口腔科学 | 10篇 |
临床医学 | 247篇 |
内科学 | 502篇 |
皮肤病学 | 42篇 |
神经病学 | 115篇 |
特种医学 | 44篇 |
外科学 | 524篇 |
综合类 | 99篇 |
一般理论 | 2篇 |
预防医学 | 175篇 |
眼科学 | 39篇 |
药学 | 261篇 |
中国医学 | 13篇 |
肿瘤学 | 196篇 |
出版年
2023年 | 24篇 |
2022年 | 27篇 |
2021年 | 82篇 |
2020年 | 76篇 |
2019年 | 72篇 |
2018年 | 58篇 |
2017年 | 73篇 |
2016年 | 83篇 |
2015年 | 103篇 |
2014年 | 104篇 |
2013年 | 137篇 |
2012年 | 191篇 |
2011年 | 212篇 |
2010年 | 126篇 |
2009年 | 89篇 |
2008年 | 171篇 |
2007年 | 157篇 |
2006年 | 137篇 |
2005年 | 138篇 |
2004年 | 96篇 |
2003年 | 92篇 |
2002年 | 65篇 |
2001年 | 50篇 |
2000年 | 36篇 |
1999年 | 41篇 |
1998年 | 16篇 |
1997年 | 24篇 |
1996年 | 9篇 |
1995年 | 12篇 |
1994年 | 9篇 |
1993年 | 7篇 |
1992年 | 22篇 |
1991年 | 13篇 |
1990年 | 17篇 |
1989年 | 17篇 |
1988年 | 11篇 |
1987年 | 13篇 |
1986年 | 11篇 |
1984年 | 10篇 |
1983年 | 10篇 |
1982年 | 7篇 |
1978年 | 9篇 |
1977年 | 6篇 |
1976年 | 10篇 |
1975年 | 6篇 |
1974年 | 9篇 |
1972年 | 11篇 |
1971年 | 7篇 |
1970年 | 6篇 |
1969年 | 6篇 |
排序方式: 共有2750条查询结果,搜索用时 0 毫秒
1.
Family-centered care (FCC) for sick newborns is emerging as a paradigmatic shift in the practice of facility-based newborn care. It seeks to transforming a provider-centered model into a client-centered one and thus build a new therapeutic alliance. FCC is the cornerstone of continuum of care, imparting caregiving competencies to parents/caregivers both within institutions as well as after the discharge. This has potential gains for the newborn, family members, and facility-level staff. The initial model piloted in tertiary-care settings is now undergoing translation at five sites across the country; the outcomes are keenly awaited. 相似文献
2.
3.
The antiproliferative, cytotoxic and apoptogenic activities of Bufo melanostictus (Indian common toad) skin extract (TSE) on U937 and K562 leukemic cell line has been investigated. TSE significantly (P<0.001) reduced the time-dependent cell proliferation and decreased MTT values in U937 and K562 cells. TSE (IC50 doses) suppressed the proliferating cell nuclear antigen expression in both the cells. It was demonstrated that, TSE (IC50 doses) primarily arrested the U937 and K562 cells at G1 phase of the cell cycle. Confocal microscopy showed the altered fragmented nuclei and apoptotic bodies formation in TSE (IC50 doses) treated U937 and K562 cells. Membrane blebbing, cell surface shrinkage and perforation were observed through scanning electron microscope. TSE-induced DNA fragmentation in U937 and K562 cells was reflected in single-cell gel electrophoresis. TSE significantly (P<0.001) increase the length-width ratio of DNA mass as compared to control in comet assay. The flow cytometric analysis of annexin-V binding to the cancer cells further supported the apoptotogenic activity of TSE. The effect of TSE on normal human peripheral blood mononuclear cells viability and cytotoxicity was studied in culture and found to be less cytotoxic than on the U937 and K562 cells. The findings from the present study suggested that TSE might possess potent antineoplastic agent having antiproliferative, cytotoxic and apoptogenic activity against U937 and K562 myeloid leukemic cells. 相似文献
4.
5.
Shyamal K Das Tapas K Banerjee Atanu Biswas Trishit Roy Deepak K Raut Arijit Chaudhuri Abhijit Hazra 《Movement disorders》2007,22(14):2031-2036
An epidemiological study on dystonia has not been reported from India. As part of a major study to find out the prevalence of major neurological disorders in the large urban city of Kolkata, Eastern India, we planned to determine the prevalence of primary dystonia. The study design was a cross-sectional study of a sample population obtained through stratified random selection and conducted in a two-stage procedure of screening by a nonprofessional team followed by confirmation of screened positive cases by the study neurologist. A total population of 52,377 was screened, and 29 subjects with dystonia were diagnosed. Out of them 23 subjects had primary dystonias [crude prevalence rate (CPR), 43.91/100,000; 95% confidence interval (CI), 28.41-64.81; age-standardized rates to world standard population, 49.06 (95% CI,31.74-72.41)] and all cases were focal type and predominantly of limb dystonia variety. Mean onset of dystonias were earlier in women (43.5 years) as compared to men (46.6 years). Thus our study on primary dystonia shows higher prevalence when compared with that of many studies globally, predominantly of focal type, earlier onset among women, and more cases of limb dystonias when compared with more prominent blepharospasm and cervical dystonias in western reports. 相似文献
6.
K E Rogers P Dasgupta U Gubler M Grillo Y S Khew-Goodall F L Margolis 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(6):1704-1708
cDNA clones corresponding to mRNA for rat olfactory marker protein (OMP) were isolated from a cDNA library. The library was constructed from olfactory mucosa poly(A)+ RNA enriched for OMP mRNA and cloned into a pBR322-derived plasmid, pMG5. OMP cDNA clones were detected by using a 17-base oligonucleotide probe that contained all 16 possible sequences coding for a known partial amino acid sequence of rat OMP. The identity of these clones was confirmed by hybrid-selected translation and nucleotide sequencing. The sequence of one clone was determined and contained the complete OMP coding region of 486 nucleotides followed by 1630 nucleotides of the 3' untranslated region. The 3' untranslated region included the polyadenylylation signal 16 nucleotides upstream of the poly(A) tail. No other ATG-initiated open reading frame larger than 20 codons was present in register. RNA blot analysis of olfactory mucosa poly(A)+ RNA using this clone as a probe indicated that the level of OMP mRNA, but not its size, declined significantly within a few days following olfactory bulbectomy. OMP mRNA was not detected in 14 nonolfactory rat tissues. Surprisingly, a small amount of OMP mRNA was observed in olfactory bulb. The presence of OMP mRNA in olfactory bulb was confirmed by in vitro translation and immunoprecipitation. These results suggest either that a previously undescribed population of neurons in the olfactory bulb synthesize OMP or that OMP mRNA is transported to the bulb by axonal transport. 相似文献
7.
8.
Competitive binding to a charged leucine motif represses transformation by a papillomavirus E6 oncoprotein 总被引:2,自引:0,他引:2
E6 oncoproteins from HPV-16 and bovine papillomavirus type 1 (BPV-1) bind to similar leucine-rich peptides termed charged leucine motifs found on the cellular focal adhesion protein paxillin and the E3 ubiquitin ligase E6AP. BPV-1 E6 (BE6) mutants that do not bind to paxillin are defective at inducing cellular transformation. It is possible, however, that BE6 mutants that do not bind paxillin are defective for transformation for an unrelated reason than the ability to bind to charged leucine motifs. To address the role of BE6 interaction with charged leucine motifs, we fused a BE6-binding charged leucine motif to the amino terminus of BE6, thereby creating an autoinhibitory binding domain. We found that the fusion protein failed to bind to paxillin or transform murine C127 cells. Mutation of the amino terminal binding motif in the fusion protein restored both interaction with paxillin and transformation. This demonstrates that BE6 transformation requires binding to charged leucine motifs on particular cellular proteins and that transformation by papillomavirus oncoproteins can be repressed by competitive interactions with charged leucine motifs. 相似文献
9.
Cystic duct and Heister's "valves" 总被引:2,自引:0,他引:2
The anatomy and physiology of the cystic duct have been relatively neglected by anatomists and the function of the spiral mucosal folds or "valves" of Heister, first described in 1732, remains obscure. The gross and microscopic anatomy of the cystic duct is reviewed together with results from laboratory investigations into the function of the cystic duct and its spirally arranged folds. The duct and spiral folds contain muscle fibers responsive to pharmacologic, hormonal, and neural stimuli. There is, however, no convincing evidence of a discrete muscular sphincter within the duct. Although the cystic duct is unlikely to play a major role in gallbladder filling and emptying, it appears to function as more than a passive conduit. Coordinated, graded muscular activity in the cystic duct in response to hormonal and neural stimuli may facilitate gallbladder emptying. The principal function of the internal spiral folds that are found in man and other animals may be to preserve patency of this narrow, tortuous tube rather than to regulate bile flow. 相似文献
10.
Mysorekar VV Dandekar CP Satyaprakash BS Sarkar A 《Indian journal of pathology & microbiology》2003,46(1):37-43
Endoscopic biopsies obtained from 275 patients (180 from the upper gastrointestinal tract and 95 from the lower gastrointestinal tract) were studied to compare the accuracy of biopsy imprint cytology and histology in the diagnosis of gastrointestinal lesions, and also to establish the degree of reliability of imprint cytology alone for an early diagnosis of malignancy. Biopsy histology results were found to be correct in 100% cases. Imprint cytology had an overall accuracy of 100%, 96.7%, 95.8% and 95.8% for the diagnosis of malignancies of the oesophagus, stomach, duodenum and colorectum respectively. False negative results were obtained with lymphomas. Regenerative cellular atypia was an important cause for false positive results. It was concluded that imprint cytology can serve as a useful and simple tool for an immediate diagnosis of malignancy. This should be subsequently correlated with histopathology which facilitates exact tumour typing and assessment of tumour invasion. 相似文献