全文获取类型
收费全文 | 279篇 |
免费 | 16篇 |
国内免费 | 2篇 |
专业分类
儿科学 | 4篇 |
基础医学 | 86篇 |
临床医学 | 6篇 |
内科学 | 60篇 |
皮肤病学 | 12篇 |
神经病学 | 9篇 |
特种医学 | 18篇 |
外科学 | 27篇 |
综合类 | 3篇 |
一般理论 | 1篇 |
预防医学 | 14篇 |
药学 | 37篇 |
中国医学 | 2篇 |
肿瘤学 | 18篇 |
出版年
2024年 | 1篇 |
2023年 | 4篇 |
2021年 | 12篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 3篇 |
2017年 | 8篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2014年 | 9篇 |
2013年 | 14篇 |
2012年 | 16篇 |
2011年 | 29篇 |
2010年 | 3篇 |
2009年 | 9篇 |
2008年 | 13篇 |
2007年 | 23篇 |
2006年 | 11篇 |
2005年 | 10篇 |
2004年 | 18篇 |
2003年 | 22篇 |
2002年 | 21篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1995年 | 1篇 |
1993年 | 2篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1975年 | 3篇 |
排序方式: 共有297条查询结果,搜索用时 31 毫秒
1.
We have developed a method for obtaining pneumococcal lipoteichoic acid (LTA) with none, one, or two acyl chains. Anion-exchange chromatography at pH 9.5 yields pneumococcal LTA (labeled LTA-9.5) that has a mass spectrum identical to that of pre-ion-exchange LTA and loses 500 mass units after deacylation by alkali hydrolysis. Anion exchange at pH 10.5 produces LTA (labeled LTA-10.5) with mass peaks that are 264 mass units lower than those of pre-ion-exchange LTA, and deacylation of LTA-10.5 by alkali hydrolysis reduces the mass by only 239 mass units. This result indicates that LTA-10.5 has lost one of the two acyl chains, whereas LTA-9.5 has both acyl chains. When the biological properties of LTA-9.5 and LTA-10.5 are examined with mouse cells, only LTA-9.5 (and not LTA-10.5) is able to stimulate mouse cells to produce tumor necrosis factor alpha, interleukin-1beta, and nitric oxide. In contrast, both LTA-9.5 and LTA-10.5 can stimulate human cells. LTA became inactive when both acyl chains were removed. Thus, acyl chains are critical for LTA function, and small variations in acyl chains can alter biological properties of LTA. 相似文献
2.
Uffe A. Brodthagen Knud NØrregaard Hansen Jens Bjerre Knudsen Robert Jordal Ole Kristensen Poul -Erik Paulev 《European journal of applied physiology》1985,53(4):334-338
Summary 20 male elite long distance runners were compared to a control group of blood donors to determine the effect of training on red blood cells. The acute effects of exercise on red cells were investigated in 11 of the runners following a race of 15–30 km. The runners had elevated resting values of red cell 2,3-DPG (P<0.05) and mean cell volume (P<0.01); blood Hb and ATP were not different from concentrations in the control group. The red cell status of the athletes may be explained by an increased proportion of young erythrocytes in runners. No statistically significant changes in red cell 2,3-DPG, ATP, mean cell volume or blood Hb were found post exercise. 相似文献
3.
4.
Torsten B. Rasmussen Johan Palmfeldt Peter H. Nissen Raffaela Magnoni Søren Dalager Uffe B. Jensen Won Y. Kim Lene Heickendorff Henning Mølgaard Henrik K. Jensen Ulrik T. Baandrup Peter Bross Jens Mogensen 《Human mutation》2013,34(5):697-705
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a hereditary cardiac condition associated with ventricular arrhythmias, heart failure, and sudden death. The most frequent ARVC genes encode desmosomal proteins of which mutations in desmoglein‐2 (DSG2), account for 10%–20% of cases. This study aimed to investigate how DSG2 mutations contribute to the pathogenesis of ARVC. Initial mutation analysis of DSG2 in 71 probands identified the first family reported with recessively inherited ARVC due to a missense mutation. In addition, three recognized DSG2 mutations were identified in 12 families. These results and further mutation analyses of four additional desmosomal genes indicated that ARVC caused by DSG2 mutations is often transmitted by recessive or digenic inheritance. Because desmosomal proteins are also expressed in skin tissue, keratinocytes served as a cell model to investigate DSG2 protein expression by Western blotting, 2D‐PAGE, and liquid chromatography–mass spectrometry. The results showed that heterozygous mutation carriers expressed both mutated and wild‐type DSG2 proteins. These findings were consistent with the results obtained by immunohistochemistry of endomyocardial biopsies and epidermal tissue of mutation carriers, which indicated a normal cellular distribution of DSG2. The results suggested a dominant‐negative effect of the mutated DSG2 proteins because they were incorporated into the desmosomes. 相似文献
5.
Østergaard M Duer A Møller U Ejbjerg B 《Best Practice & Research: Clinical Rheumatology》2004,18(6):861-879
The need for better methods than the conventional clinical, biochemical and radiographical examinations in the management of inflammatory joint diseases is evident, since these methods are not sensitive or specific to early pathologies and subtle changes. Magnetic resonance imaging (MRI) offers improved sensitivity to early inflammatory and destructive changes in peripheral joints in rheumatoid arthritis (RA) and, even though less well documented, in other inflammatory joint diseases. Good evidence is available that MRI bone erosions represent true bone abnormalities and are predictors of radiographical outcome in RA. Similarly, there is solid evidence for MRI synovitis representing true synovial inflammation and being of considerable practical, clinical and radiological significance in RA. Describing the encouraging current knowledge regarding MRI for diagnosis, monitoring and prognosis, this chapter discusses the potential for the use of MRI in the clinical management of patients with suspected and diagnosed inflammatory joint diseases, as well as research priorities and clinical situations where the use of MRI could be suggested. 相似文献
6.
Dr. Lars S. JØrgensen M.D. Uffe Raundahl M.D. Lars L. Knudsen M.S. Karin AksglÆde M.D. Per SØgaard Ph.D. 《Diseases of the colon and rectum》1991,34(7):594-599
A new aseptic colon resection by an invagination technique is presented. The bowel to be resected is invaginated down into the healthy intestine, and the anastomosis is sutured in one layer of continuous suture before transection by a diathermy wire, placed in the intestinal lumen via the anus. Sections of bowel that cannot be invaginated,e.g.,because of a tumor, are first removed by transection between pairs of cable ties, which close the lumen. Twenty dogs were operated on without receiving prophylactic antibiotics. In 10, the intestine was transected between cable ties. An imprint, taken from the anastomosis and subcutis, was cultured. The bacterial count at the anastomosis exceeded 100 in only three cases; in the subcutis, this was the case in one dog. One wound infection developed. Serial barium enemas at 1, 2, 3, and 4 weeks revealed no anastomotic leakage. One early death because of a total anastomotic dehiscence was encountered, and two dogs were killed because of wound dehiscence and anastomotic stricture, respectively. It is concluded that, in dogs, the method is easily and safely performed, but further experimental studies are needed.This study was supported with grants from Fonden til Laegevidenskabens Fremme, Kraeftens Bekaempelse, Sygekassernes Helsefond, and Aarhus Universitets Forskningsfond. 相似文献
7.
8.
Gro G. Pløen Line Nederby Per Guldberg Maria Hansen Lene H. Ebbesen Uffe Birk Jensen Peter Hokland Anni Aggerholm 《British journal of haematology》2014,167(4):478-486
Mutations in DNMT3A, the gene encoding DNA methyltransferase 3 alpha, have been identified as molecular drivers in acute myeloid leukaemia (AML) with possible implications for minimal residual disease monitoring and prognosis. To further explore the utility of DNMT3A mutations as biomarkers for AML, we developed assays for sensitive detection of recurrent mutations affecting residue R882. Analysis of DNA from 298 diagnostic AML samples revealed DNMT3A mutations in 45 cases (15%), which coincided with mutations in NPM1, FLT3 and IDH1. DNMT3A mutations were stable in 12 of 13 patients presenting with relapse or secondary myelodysplastic syndrome, but were also present in remission samples from 14 patients (at allele frequencies of <1–50%) up to 8 years after initial AML diagnosis, despite the loss of all other molecular AML markers. The mutant DNMT3A allele burden was not related to the clinical course of disease. Cell sorting demonstrated the presence of DNMT3A mutations in leukaemic blasts, but also at lower allele frequencies in T and B‐cells from the same patients. Our data are consistent with the recent finding of preleukaemic stem cells in AML, which are resistant to chemotherapy. The persistence of DNMT3A mutations during remission may have important implications for the management of AML. 相似文献
9.
10.
Pedersen MØ Gang AO Poulsen TS Knudsen H Lauritzen AF Nielsen SL Gang UO Nørgaard P 《European journal of haematology》2012,89(1):63-71
Concurrent BCL2 and MYC translocations, so called double hit (DH), are a rare finding in large B-cell lymphoma (LBCL). Based on data from retrospective series, DH has been correlated with aggressive clinical behaviour and poor outcome. We conducted a consecutive study of DH incidence and correlation with pathologic and clinical characteristics, including response to Rituximab-containing chemotherapy and survival, in an unselected cohort of patients with LBCL. Translocations involving BCL2 and MYC loci were examined with fluorescent in situ hybridization (FISH) in 157 patients with diffuse large B-cell lymphoma (DLBCL) or B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma (BCLU). The incidence of DH was 11% in the total cohort, 7% of primary LBCL and 21% of transformed LBCL. DH lymphomas were all GCB immunophenotype and were more often BCLU. No clinical characteristics were correlated with the presence of DH, which also had no impact on overall response rate (ORR), relapse rate or overall survival (OS). However, sub-stratification of DH lymphomas by FISH indicated a possible inferior survival related to immunoglobulin MYC translocation partner gene. Screening of patients with BCLU and DLBCL of GCB type for DH BCL2/MYC translocation including MYC translocation partner gene may provide important prognostic information. 相似文献