全文获取类型
收费全文 | 378篇 |
免费 | 26篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 24篇 |
妇产科学 | 8篇 |
基础医学 | 53篇 |
口腔科学 | 4篇 |
临床医学 | 36篇 |
内科学 | 114篇 |
皮肤病学 | 5篇 |
神经病学 | 20篇 |
特种医学 | 35篇 |
外科学 | 31篇 |
综合类 | 6篇 |
预防医学 | 25篇 |
眼科学 | 13篇 |
药学 | 19篇 |
中国医学 | 1篇 |
肿瘤学 | 18篇 |
出版年
2023年 | 1篇 |
2022年 | 9篇 |
2021年 | 8篇 |
2020年 | 3篇 |
2019年 | 8篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 8篇 |
2015年 | 7篇 |
2014年 | 11篇 |
2013年 | 13篇 |
2012年 | 18篇 |
2011年 | 13篇 |
2010年 | 10篇 |
2009年 | 16篇 |
2008年 | 21篇 |
2007年 | 22篇 |
2006年 | 18篇 |
2005年 | 21篇 |
2004年 | 17篇 |
2003年 | 10篇 |
2002年 | 16篇 |
2001年 | 12篇 |
2000年 | 16篇 |
1999年 | 9篇 |
1998年 | 13篇 |
1997年 | 10篇 |
1996年 | 6篇 |
1995年 | 6篇 |
1994年 | 10篇 |
1993年 | 10篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 4篇 |
1989年 | 9篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 6篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 6篇 |
1975年 | 2篇 |
1968年 | 1篇 |
1875年 | 1篇 |
排序方式: 共有414条查询结果,搜索用时 15 毫秒
1.
2.
Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement. 相似文献
3.
4.
A functional survey of the enhancer activity of conserved non-coding sequences from vertebrate Iroquois cluster gene deserts 总被引:7,自引:4,他引:7
de la Calle-Mustienes E Feijóo CG Manzanares M Tena JJ Rodríguez-Seguel E Letizia A Allende ML Gómez-Skarmeta JL 《Genome research》2005,15(8):1061-1072
Recent studies of the genome architecture of vertebrates have uncovered two unforeseen aspects of its organization. First, large regions of the genome, called gene deserts, are devoid of protein-coding sequences and have no obvious biological role. Second, comparative genomics has highlighted the existence of an array of highly conserved non-coding regions (HCNRs) in all vertebrates. Most surprisingly, these structural features are strongly associated with genes that have essential functions during development. Among these, the vertebrate Iroquois (Irx) genes stand out on both fronts. Mammalian Irx genes are organized in two clusters (IrxA and IrxB) that span >1 Mb each with no other genes interspersed. Additionally, a large number of HCNRs exist within Irx clusters. We have systematically examined the enhancer activity of HCNRs from the IrxB cluster using transgenic Xenopus and zebrafish embryos. Most of these HCNRs are active in subdomains of endogenous Irx expression, and some are candidates to contain shared enhancers of neighboring genes, which could explain the evolutionary conservation of Irx clusters. Furthermore, HCNRs present in tetrapod IrxB but not in fish may be responsible for novel Irx expression domains that appeared after their divergence. Finally, we have performed a more detailed analysis on two IrxB ultraconserved non-coding regions (UCRs) duplicated in IrxA clusters in similar relative positions. These four regions share a core region highly conserved among all of them and drive expression in similar domains. However, inter-species conserved sequences surrounding the core, specific for each of these UCRs, are able to modulate their expression. 相似文献
5.
Renal gluconeogenesis and increased glucose utilization in shock 总被引:1,自引:0,他引:1
6.
M. I. Queipo-Ortuño F. Tena J. D. Colmenero P. Morata 《European journal of clinical microbiology & infectious diseases》2008,27(2):109-114
We compared the relative recovery of extraction of bacterial DNA from serum using seven commercial kits (UltraClean DNA BloodSpin
Kit, Puregene DNA Purification System, Wizard Genomic DNA Purification Kit, High Pure PCR Template Preparation Kit, GFX™ Genomic
Blood DNA Purification Kit, NucleoSpin Tissue Kit, and QIAamp DNA Blood Mini Kit). Human serum samples were spiked with known
concentrations of Brucella melitensis Rev 1; the DNA was extracted and tested in genus-specific LightCycler polymerase chain reaction (PCR). The UltraClean DNA
BloodSpin Kit proved to be as sensitive as the QIAamp DNA Blood Mini Kit isolation method and could detect down to 100 fg
of DNA, though only the former had no contamination. All the other procedures yielded DNA isolation results that were less
sensitive and were always contaminated. Our results show that the UltraClean DNA Blood Spin Kit was the commercially available
assay tested that yielded the best sensitivity, purity, and lack of contamination for Brucella DNA isolation from serum. 相似文献
7.
Brain malformations such as agenesis and dysgenesis of corpus callosum, pituitary hypoplasia, hypothalamic hamartoma, mesial temporal periventricular heterotopia, and abnormally oriented and misshapen hippocampi have been described with SOX2 gene mutations. A neocortical malformation is presented here in association with SOX2 deletion that over time underwent spontaneous evolution and decrease in size. 相似文献
8.
Carmona L Hernández-García C Vadillo C Pato E Balsa A González-Alvaro I Belmonte MA Tena X Sanmartí R;EMECAR Study Group 《The Journal of rheumatology》2003,30(7):1436-1439
OBJECTIVE: To quantify the risk of tuberculosis (TB) in an unselected sample of patients with rheumatoid arthritis (RA) compared to the risk in the general population. METHODS: The incidence of TB in the general population of Spain was obtained from the National Network of Epidemiological Surveillance reports. The incidence of TB was ascertained from a cohort of 788 patients with RA selected randomly from the registries of 34 participating centers throughout Spain. A patient was considered a TB case only if information about disease symptoms, microorganism identification, and TB treatment were confirmed in the clinical records. The relative risk of TB in RA was calculated by dividing the standardized mean incidence of TB from 1990 to 2000 in the RA cohort by the mean incidence of TB in Spain during the same years. RESULTS: The mean incidence of TB in the general population of Spain from 1990 to 2000 was 23 cases per 100,000. Seven cases of TB were identified in the RA cohort, yielding a mean annual incidence (1990-2000) of 134/100,000 patients. The incidence risk ratio of pulmonary TB in patients with RA compared to the general population is 3.68 (95% CI 2.36-5.92). CONCLUSION: We found a 4-fold increased risk of TB infection in patients diagnosed with RA. These results might help to interpret the magnitude of the problem attributable to the introduction of new therapies in RA. 相似文献
9.
Lord BI; Woolford LB; Wood LM; Czaplewski LG; McCourt M; Hunter MG; Edwards RM 《Blood》1995,85(12):3412-3415
BB-10010 is a genetically engineered variant of human macrophage inflammatory protein-1 alpha with improved solution properties. We show here that it mobilizes stem cells into the peripheral blood. We investigated the mobilizing effects of BB-10010 on the numbers of circulating 8-day spleen colony-forming units (CFU-S8), CFU-S12, and progenitors with marrow repopulating ability (MRA). A single subcutaneous dose of BB-10010 caused a twofold increase in circulating numbers of CFU-S8, CFU-S12, and MRA 30 minutes after dosing. We also investigated the effects of granulocyte colony-stimulating factor (G- CSF) and the combination of G-CSF with BB-10010 on progenitor mobilization. Two days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA progenitors by 25.7-, 19.8-, and 27.7-fold. A single administration of BB-10010 after 2 days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA even further to 38-, 33-, and 100- fold. Splenectomy resulted in increased circulating progenitor numbers but did not change the pattern of mobilization. Two days of treatment with G-CSF then increased circulating CFU-S8, CFU-S12, and MRA by 64-, 69-, and 32-fold. A single BB-10010 administration after G-CSF treatment further increased them to 85-, 117-, and 140-fold, respectively, compared with control. We conclude that BB-10010 causes a rapid increase in the number of circulating hematopoietic progenitors and further enhances the numbers induced by pretreatment with G-CSF. BB- 10010 preferentially mobilized the more primitive progenitors with marrow repopulating activity, releasing four times the number achieved with G-CSF alone. Translated into a clinical setting, this improvement in progenitor cell mobilization may enhance the efficiency of harvest and the quality of grafts for peripheral blood stem cell transplantation. 相似文献
10.
Systematic Review of Quality Improvement Initiatives Related to Cue-Based Feeding in Preterm Infants