全文获取类型
收费全文 | 594篇 |
免费 | 75篇 |
国内免费 | 22篇 |
专业分类
儿科学 | 73篇 |
妇产科学 | 14篇 |
基础医学 | 148篇 |
口腔科学 | 9篇 |
临床医学 | 68篇 |
内科学 | 134篇 |
皮肤病学 | 4篇 |
神经病学 | 13篇 |
特种医学 | 75篇 |
外科学 | 30篇 |
综合类 | 18篇 |
一般理论 | 1篇 |
预防医学 | 42篇 |
眼科学 | 1篇 |
药学 | 25篇 |
中国医学 | 6篇 |
肿瘤学 | 30篇 |
出版年
2021年 | 6篇 |
2018年 | 5篇 |
2015年 | 8篇 |
2014年 | 8篇 |
2013年 | 18篇 |
2012年 | 6篇 |
2011年 | 14篇 |
2010年 | 17篇 |
2009年 | 8篇 |
2008年 | 22篇 |
2007年 | 34篇 |
2006年 | 28篇 |
2005年 | 19篇 |
2004年 | 12篇 |
2003年 | 8篇 |
2002年 | 17篇 |
2001年 | 5篇 |
2000年 | 7篇 |
1999年 | 14篇 |
1998年 | 20篇 |
1997年 | 25篇 |
1996年 | 15篇 |
1995年 | 17篇 |
1994年 | 12篇 |
1993年 | 13篇 |
1992年 | 7篇 |
1991年 | 8篇 |
1990年 | 11篇 |
1989年 | 22篇 |
1988年 | 17篇 |
1987年 | 11篇 |
1986年 | 26篇 |
1985年 | 9篇 |
1984年 | 9篇 |
1983年 | 13篇 |
1982年 | 11篇 |
1981年 | 8篇 |
1980年 | 9篇 |
1979年 | 8篇 |
1978年 | 19篇 |
1977年 | 17篇 |
1976年 | 11篇 |
1975年 | 10篇 |
1974年 | 13篇 |
1973年 | 12篇 |
1972年 | 14篇 |
1971年 | 11篇 |
1970年 | 11篇 |
1969年 | 9篇 |
1967年 | 8篇 |
排序方式: 共有691条查询结果,搜索用时 619 毫秒
81.
Orho-Melander M Melander O Guiducci C Perez-Martinez P Corella D Roos C Tewhey R Rieder MJ Hall J Abecasis G Tai ES Welch C Arnett DK Lyssenko V Lindholm E Saxena R de Bakker PI Burtt N Voight BF Hirschhorn JN Tucker KL Hedner T Tuomi T Isomaa B Eriksson KF Taskinen MR Wahlstrand B Hughes TE Parnell LD Lai CQ Berglund G Peltonen L Vartiainen E Jousilahti P Havulinna AS Salomaa V Nilsson P Groop L Altshuler D Ordovas JM Kathiresan S 《Diabetes》2008,57(11):3112-3121
OBJECTIVE—Using the genome-wide association approach, we recently identified the glucokinase regulatory protein gene (GCKR, rs780094) region as a novel quantitative trait locus for plasma triglyceride concentration in Europeans. Here, we sought to study the association of GCKR variants with metabolic phenotypes, including measures of glucose homeostasis, to evaluate the GCKR locus in samples of non-European ancestry and to fine- map across the associated genomic interval.RESEARCH DESIGN AND METHODS—We performed association studies in 12 independent cohorts comprising >45,000 individuals representing several ancestral groups (whites from Northern and Southern Europe, whites from the U.S., African Americans from the U.S., Hispanics of Caribbean origin, and Chinese, Malays, and Asian Indians from Singapore). We conducted genetic fine-mapping across the ∼417-kb region of linkage disequilibrium spanning GCKR and 16 other genes on chromosome 2p23 by imputing untyped HapMap single nucleotide polymorphisms (SNPs) and genotyping 104 SNPs across the associated genomic interval.RESULTS—We provide comprehensive evidence that GCKR rs780094 is associated with opposite effects on fasting plasma triglyceride (Pmeta = 3 × 10−56) and glucose (Pmeta = 1 × 10−13) concentrations. In addition, we confirmed recent reports that the same SNP is associated with C-reactive protein (CRP) level (P = 5 × 10−5). Both fine-mapping approaches revealed a common missense GCKR variant (rs1260326, Pro446Leu, 34% frequency, r2 = 0.93 with rs780094) as the strongest association signal in the region.CONCLUSIONS—These findings point to a molecular mechanism in humans by which higher triglycerides and CRP can be coupled with lower plasma glucose concentrations and position GCKR in central pathways regulating both hepatic triglyceride and glucose metabolism.Recently, in the genome-wide association Diabetes Genetics Initiative (DGI) Study for 19 traits, including plasma lipids, we provided evidence that the glucokinase (GCK) regulatory protein gene (GCKR) region was a novel quantitative trait locus associated with plasma triglyceride concentration (1). Of all single nucleotide polymorphisms (SNPs) tested, an intronic SNP at GCKR (rs780094) explained the greatest proportion of interindividual variability in plasma triglycerides (1).GCKR regulates GCK, which functions as a glucose sensor responsible for glucose phosphorylation in the first step of glycolysis. The discoveries that inactivating mutations in GCK cause maturity onset diabetes of the young type 2 (2) and activating GCK mutations lead to permanent hyperinsulinemic hypoglycemia (3) emphasize that GCK plays a major role in glucose metabolism. GCKR-deficient mice have reduced GCK expression but maintain nearly normal GCK activity and show impaired glucose clearance (4). Furthermore, adenoviral-mediated overexpression of GCKR in mouse liver increased GCK activity and lowered fasting blood glucose (5) and overexpression of GCK in liver led to lowered blood glucose and increased triglyceride concentrations (6,7). Thus, experimental evidence suggests that perturbation of the GCKR pathway has opposing effects of triglyceride and glucose metabolism.In our original report, SNP rs780094 in GCKR was associated with fasting triglyceride levels in two independent samples, each of Northern European ancestry (P = 3.7 × 10−8 and 8.7 × 10−8, respectively) (1). After initial identification and replication of a chromosomal region associated with a trait, key next steps include extension of the association finding to related phenotypes, validation of the association finding in different ethnicities, and fine- mapping to identify the putative causal variant. Recently, our initial finding was replicated in a Danish study in which a strong association was found between the rs780094 T allele and elevated fasting triglyceride levels but also lower insulin levels, better insulin sensitivity, and a moderately decreased risk of type 2 diabetes (8). In addition, recent genome-wide association studies identified an association between the same GCKR intronic SNP and C-reactive protein (CRP) levels (9,10).Hereby, we sought to examine the effect of SNP rs780094 on triglycerides and related metabolic traits, including fasting glucose concentrations, in 12 samples representing a range of ancestral groups and including a large prospective study with a mean follow-up time of 23 years. In addition, we performed fine-mapping in one of these samples to identify the strongest association signal in the region. 相似文献
82.
Olutobi A. Sanuade MPHIL PhD Boni M. Ale MD MSc MPH Abigail S. Baldridge MS Ikechukwu A. Orji MBBS MPH PhD Gabriel L. Shedul MD MPH Tunde M. Ojo MD MSc Grace Shedul PharmD Eugenia N. Ugwuneji MSc FPCPharm Nonye Egenti MD MPH Kasarachi Omitiran MBBS FWACP Rosemary Okoli PhD Helen Eze MBBS Ada Nwankwo MBBCh Lisa R. Hirschhorn MD MPH Aashima Chopra MPH Jiancheng Ye MS Priya Tripathi MS Bolanle Banigbe MD MPH DrPH Namratha R. Kandula MD MPH Mark D. Huffman MD MPH Dike B. Ojji MD PhD the Hypertension Treatment in Nigeria Program Investigators 《Journal of clinical hypertension (Greenwich, Conn.)》2023,25(2):127-136
Fixed-dose combination (FDC) therapy is recommended for hypertension management in Nigeria based on randomized trials at the individual level. This cluster-randomized trial evaluates effectiveness and safety of a treatment protocol that used two-drug FDC therapy as the second and third steps for hypertension control compared with a protocol that used free pill combinations. From January 2021 to June 2021, 60 primary healthcare centers in the Federal Capital Territory of Nigeria were randomized to a protocol using FDC therapy as second and third steps compared with a protocol that used the same medications in free pill combination therapy for these steps. Eligible patients were adults (≥18 years) with hypertension. The primary outcome was the odds of a patient being controlled at their last visit between baseline to 6-month follow-up in the FDC group compared to the free pill group. 4427 patients (mean [SD] age: 49.0 [12.4] years, 70.5% female) were registered with mean (SD) baseline systolic/diastolic blood pressure 155 (20.6)/96 (13.1) mm Hg. Baseline characteristics of groups were similar. After 6-months, hypertension control rate improved in the two treatment protocols, but there were no differences between the groups after adjustment (FDC = 53.9% versus free pill combination = 47.9%, cluster-adjusted p = .29). Adverse events were similarly low (<1%) in both groups. Both protocols improved hypertension control rates at 6-months in comparison to baseline, though no differences were observed between groups. Further work is needed to determine if upfront FDC therapy is more effective and efficient to improve hypertension control rates. 相似文献
83.
Tsujino S Huie M Kanazawa N Sugie H Goto Y Kawai M Nonaka I Hirschhorn R Sakuragawa N 《Neuromuscular disorders : NMD》2000,10(8):599-603
We screened 22 Japanese patients with acid maltase deficiency (seven with the infantile type, eight with the juvenile type and seven with the adult type) for three previously described mutations, D645E, S529V and R672Q, and a novel mutation, R600C. Although D645E has been reported to be common in Chinese patients with the infantile type, only three of 44 alleles (two of 14 infantile type alleles) from Japanese patients harbored the D645E mutation. The S529V mutation was identified in six of 14 alleles from adult-onset patients. None of the infantile or juvenile patients harbored the S529V mutation. Therefore, S529V apparently results in the adult type disease and is common in Japanese adult-onset patients. R672Q was identified in two pairs of siblings with the juvenile type. A novel mutation, R600C, was identified in eight of 22 patients (nine of 44 alleles). Therefore, R600C is another common Japanese mutation occurring at a CpG dinucleotide “hot spot”. Homozygosity for this mutation apparently results in the infantile phenotype. Genetic diagnosis by detecting these four mutations might be feasible for most Japanese patients with acid maltase deficiency. 相似文献
84.
85.
冠状动脉搭桥术早期并发症及死亡率(附196例报告) 总被引:1,自引:0,他引:1
1985年1月~1987年12月作者于荷兰格罗宁根医学科学院心胸外科主做了196例冠状动脉搭桥术。术后早期死亡2例(1.0%)、内出血3例(1.5%)、胸骨裂开2例(1.0%)、心律紊乱40例(20.4%)、围手术期心肌梗塞5例(2.6%),本文就术后早期并发症进行了讨论。 相似文献
86.
The proximity of child's kidneys from the cutaneous surface allows a particularly sensitive exploration by doppler sonography, which in addition has the major advantage of being a non-invasive, non-irradiating and painless technique. However there are two limitations to this technique: the lack of cooperation of some children and the still limited availability of high quality equipment in intensive care units. Indeed most of the applications described in this paper (ie. pyelonephritis, renovascular hypertension, tumors, acute renal insufficiency and renal vein thrombosis) require, besides an experienced operator, expensive power doppler equipment including high frequency and high resolution probes. 相似文献
87.
Direct demonstration that autologous bone marrow transplantation for solid tumors can return a multiplicity of tumorigenic cells 总被引:5,自引:2,他引:5
Rill DR; Santana VM; Roberts WM; Nilson T; Bowman LC; Krance RA; Heslop HE; Moen RC; Ihle JN; Brenner MK 《Blood》1994,84(2):380-383
Patients with solid tumors are increasingly being treated by autologous bone marrow transplantation (BMT). Although response rates appear to be increased, disease recurrence is the commonest cause of treatment failure. Whether relapse is entirely due to residual disease in the patient or arises also from infiltrating malignant cells contained in the autologous marrow transplant has not been resolved. If the latter explanation is correct, then purging would be required as part of the transplantation procedure. We used retrovirally mediated transfer of the neomycin-resistance gene to mark BM harvested from eight patients with neuroblastoma in clinical remission. The marked marrow cells were subsequently reinfused as part of an autologous BMT. At relapse, we sought the marker gene in malignant cell populations. Three patients have relapsed, and in each the marker gene was detected by phenotypic and genetic analyses of resurgent malignant cells at medullary and extramedullary sites. Analysis of neuroblast DNA for discrete marker gene integration sites suggested that at least 200 malignant cells, each capable of tumor formation, were introduced with the autologous marrow transplant and contributed to relapse. Thus, autologous BMTs administered to patients with this solid tumor may contain a multiplicity of malignant cells that subsequently contribute to relapse. The marker-gene technique we describe should permit evaluation of the mechanisms of relapse and the efficacy of purging in patients receiving autologous marrow transplantation for other solid tumors that infiltrate the marrow. 相似文献
88.
L Laval R Martin JN Natividad F Chain S Miquel C Desclée de Maredsous S Capronnier H Sokol EF Verdu JET van Hylckama Vlieg LG Bermúdez-Humarán T Smokvina P Langella 《Gut microbes》2015,6(1):1-9
Impaired gut barrier function has been reported in a wide range of diseases and syndromes and in some functional gastrointestinal disorders. In addition, there is increasing evidence that suggests the gut microbiota tightly regulates gut barrier function and recent studies demonstrate that probiotic bacteria can enhance barrier integrity. Here, we aimed to investigate the effects of Lactobacillus rhamnosus CNCM I-3690 on intestinal barrier function. In vitro results using a Caco-2 monolayer cells stimulated with TNF-α confirmed the anti-inflammatory nature of the strain CNCM I-3690 and pointed out a putative role for the protection of the epithelial function. Next, we tested the protective effects of L. rhamnosus CNCM I-3690 in a mouse model of increased colonic permeability. Most importantly, we compared its performance to that of the well-known beneficial human commensal bacterium Faecalibacterium prauznitzii A2-165. Increased colonic permeability was normalized by both strains to a similar degree. Modulation of apical tight junction proteins expression was then analyzed to decipher the mechanism underlying this effect. We showed that CNCM I-3690 partially restored the function of the intestinal barrier and increased the levels of tight junction proteins Occludin and E-cadherin. The results indicate L. rhamnosus CNCM I-3690 is as effective as the commensal anti-inflammatory bacterium F. prausnitzii to treat functional barrier abnormalities. 相似文献
89.
HIV/AIDS patients’ perspectives on adhering to regimens containing protease inhibitors 总被引:1,自引:2,他引:1
下载免费PDF全文
![点击此处可从《Journal of general internal medicine》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dr. Valerie E. Stone MD MPH Jennifer Clarke MD Joan Lovell Kathleen A. Steger RN MPH Lisa R. Hirschhorn MD MPH Stephen Boswell MD Alicia D. Monroe MD Michael D. Stein MD Tamra J. Tyree BA Kenneth H. Mayer MD 《Journal of general internal medicine》1998,13(9):586-593
OBJECTIVE: To gather qualitative data regarding HIV/AIDS patients’ perspectives about HIV-1 protease inhibitors (PIs), and about their
experiences taking and adhering to regimens containing PIs.
DESIGN: Six focus groups of persons under care for HIV were conducted between September and November 1996 regarding participants’
knowledge, awareness, experiences when taking, and adherence to antiretroviral regimens containing PIs. An identical discussion
guide was used to facilitate all six groups. Focus group proceedings were audiotaped, transcribed, coded for themes, and analyzed
qualitatively.
SETTING: HIV/AIDS practices of three teaching hospitals and two community health centers.
PATIENTS/PARTICIPANTS: Fifty-six patients with HIV disease: 28 men and 28 women.
MEASUREMENTS AND MAIN RESULTS: Knowledge and positive impressions of PIs were prevalent among this diverse group of persons with HIV, and did not differ
by race/ethnicity or gender. Most knew that these were new, potent medications for treating HIV/AIDS. Networks of persons
with HIV and medical providers were the most important information sources. Those taking PIs were aware that adherence to
the regimen is important, and most were using special strategies to maximize their own adherence, but expressed considerable
frustration about the central role these medication regimens had assumed in their life. A subset who did not believe they
would adhere to these regimens had declined treatment with them. Motivating factors for taking and adhering to these complex
regimens were improving CD4 counts and viral loads and the patient-provider relationship.
CONCLUSIONS: Among those with HIV/AIDS, awareness of PIs and their effectiveness is substantial, owing to the impact of informal networks
and medical providers. This early positive “reputation” of PIs may enhance motivation for adherence. Those who are taking
PIs invest substantial effort adhering to these complex regimens, but resent the need to make medications the focus of their
lives.
Preliminary findings of this study were presented at the Society of General Internal Medicine annual meeting on May 3, 1997,
and the National Conference on Women and HIV on May 6, 1997.
This research was supported by a Generalist Physician Faculty Scholar Award from the Robert Wood Johnson Foundation and a
grant from Merck and Co., Inc. 相似文献
90.
The inappropriate expression of c-myc in cells deprived of growth factors has recently been implicated in the activation of programmed cell death (apoptosis). The studies described here examine the ability of interleukin-3 (IL-3) or erythropoietin (Epo) to suppress apoptosis that occurs in association with enforced myc expression during cell cycle arrest of a murine IL-3-dependent myeloid progenitor cell line, 32D. G1 arrest was observed when culturing 32D cells to high density in medium supplemented with IL-3, or at subconfluent densities in medium supplemented with Epo. Under both conditions, endogenous c-myc expression was downregulated and viability was maintained. In clones of cells in which c-myc is constitutively expressed from a retroviral vector, enforced c-myc expression was associated with the activation of apoptosis at high cell densities. Similarly, enforced c-myc expression was deleterious to cell survival when these cells were cultured in Epo, as apoptosis was evident within 6 hours. The results support the concept that inappropriate c-myc expression activates apoptosis and that neither IL-3 nor Epo can suppress this program under these conditions. 相似文献