全文获取类型
收费全文 | 2771篇 |
免费 | 193篇 |
国内免费 | 45篇 |
专业分类
耳鼻咽喉 | 44篇 |
儿科学 | 120篇 |
妇产科学 | 33篇 |
基础医学 | 349篇 |
口腔科学 | 95篇 |
临床医学 | 354篇 |
内科学 | 445篇 |
皮肤病学 | 48篇 |
神经病学 | 97篇 |
特种医学 | 297篇 |
外科学 | 365篇 |
综合类 | 205篇 |
一般理论 | 1篇 |
预防医学 | 199篇 |
眼科学 | 25篇 |
药学 | 142篇 |
2篇 | |
中国医学 | 32篇 |
肿瘤学 | 156篇 |
出版年
2022年 | 32篇 |
2021年 | 37篇 |
2020年 | 35篇 |
2018年 | 33篇 |
2017年 | 26篇 |
2016年 | 29篇 |
2015年 | 53篇 |
2014年 | 66篇 |
2013年 | 101篇 |
2012年 | 105篇 |
2011年 | 104篇 |
2010年 | 120篇 |
2009年 | 117篇 |
2008年 | 90篇 |
2007年 | 97篇 |
2006年 | 102篇 |
2005年 | 76篇 |
2004年 | 81篇 |
2003年 | 82篇 |
2002年 | 75篇 |
2001年 | 69篇 |
2000年 | 62篇 |
1999年 | 65篇 |
1998年 | 95篇 |
1997年 | 93篇 |
1996年 | 80篇 |
1995年 | 80篇 |
1994年 | 49篇 |
1993年 | 67篇 |
1992年 | 43篇 |
1991年 | 47篇 |
1990年 | 37篇 |
1989年 | 50篇 |
1988年 | 61篇 |
1987年 | 53篇 |
1986年 | 47篇 |
1985年 | 42篇 |
1984年 | 27篇 |
1983年 | 34篇 |
1982年 | 19篇 |
1980年 | 20篇 |
1977年 | 19篇 |
1976年 | 17篇 |
1963年 | 18篇 |
1959年 | 22篇 |
1958年 | 29篇 |
1957年 | 19篇 |
1956年 | 30篇 |
1955年 | 42篇 |
1954年 | 35篇 |
排序方式: 共有3009条查询结果,搜索用时 15 毫秒
81.
Li G Hu Y Yang W Jiang Y Wang J Xiao J Hu Z Pan X Howard BV Bennett PH;DA Qing IGT Diabetes Study 《Diabetes research and clinical practice》2002,58(3):193-200
OBJECTIVE: To investigate the effects of insulin resistance (IR) and insulin secretion (IS) on the development of diabetes mellitus in individuals with impaired glucose tolerance (IGT) who underwent lifestyle interventions. METHODS: 284 out of 577 individuals with IGT identified by population-based screening in Da Qing, China, who were randomized to undergo diet change and/or increased physical activity had baseline fasting and 2 h post-load insulin determinations. They were followed for 6 years for the development of diabetes. IR and IS were assessed using calculated indices based on fasting plasma insulin and glucose. The interactions of IR, IS, obesity and plasma glucose and the effects of the lifestyle interventions were evaluated using Cox Proportional Hazards analysis. RESULTS: Both IR and IS were significantly associated with the development of diabetes. Lifestyle interventions were more effective in those with lower IT and higher IS at baseline. Diet plus exercise interventions resulted in significantly lower incidence of diabetes, even after controlling for IR, IS, BMI and 2hrPG. CONCLUSION: Both IR and beta-cell function were predictors of diabetes in Chinese with IGT. Lifestyle intervention reduced the incidence of DM and these interventions were more effective in those with less IR. 相似文献
82.
N T Huong B D Duong N V Co H T Quy L B Tung J F Broekmans M C Bosman C Verhage N Kalisvaart M W Borgdorff F G Cobelens 《The international journal of tuberculosis and lung disease》2006,10(9):963-969
SETTING: Six provinces in Vietnam where the DOTS strategy was introduced in 1989. OBJECTIVE: To assess the impact of improved tuberculosis (TB) control on TB epidemiology in Vietnam. METHODS: Data from the surveillance system in the period 1990-2003 were analysed to assess trends of notification rates and the mean ages of notified cases. Data from repeated tuberculin surveys in the period 1986-2002 were estimated to assess the prevalence of TB infection, the annual risk of infection and its trend using various cut-off points in those with and without bacille Calmette-Guérin (BCG) scar. RESULTS: Age-standardised notification rates in the period 1996-2003 declined significantly, by 2.6% to 5.9% per year, in five provinces. However, in four provinces notification rates in the age group 15-24 years increased significantly, by 4.5% to 13.6% per year, during this period. The mean age of newly diagnosed patients with smear-positive TB increased up to 1995 but decreased thereafter. The annual risk of TB infection showed a significant annual decrease (4.9% per year) in one province in surveys performed between 1986 and 1997, and in two provinces (6.6% and 4.7%) in surveys conducted between 1993 and 2002. CONCLUSION: These data suggest limited impact to date of the DOTS strategy in Vietnam. 相似文献
83.
Renata Boldrini Roberto Biselli Filippo M. Santorelli Cesare Bosman 《Ultrastructural pathology》2013,37(1):51-57
The term "neuronal ceroid lipofuscinosis" (NCL) describes a complex of inherited neurodegenerative conditions associated with storage of lipopigments in brain tissue. In 1989 Dyken proposed a classification of NCL based on the age, clinical symptoms, and ultrastructural aspects of the lipopigments. At the ultrastructural level it is possible to distinguish 5 different patterns of osmiophilic lipopigments: usual lipofuscin, fingerprint deposits, granular profiles, curvilinear bodies, and microtubular aggregates. The concept that each ultrastructural pattern was the counterpart of a specific clinical type has been proved not to be true. Advances in molecular genetic techniques have allowed the identification of defective genes and their protein products in several NCL clinical forms. Ceroid lipofuscin deposits may be ultrastructurally observed not only in neuronal cells, but also in several other sites, such as trophoblastic cells, thus permitting prenatal diagnosis. In spite of recent advances in immunohistochemical identification of biochemical markers, the ultrastructural identification of lipofuscinic pigments remains the gold standard to identify NCL, together with clinical aspects and respective gene defects. This study describes the ultrastructural aspects observed in 8 cases of NCL syndromes (3 juvenile, 3 infantile, 1 late infantile, and 1 congenital clinical form). In these patients, genetic analysis was also performed. 相似文献
84.
Interleukin-11 stimulates multilineage progenitors, but not stem cells, in murine and human long-term marrow cultures 总被引:3,自引:0,他引:3
Interleukin-11 (IL-11) is a bone marrow microenvironment-derived growth factor with pleiotropic effects on a variety of hematopoietic cells. To more accurately assess the effects of IL-11 on stem and progenitor compartments within the hematopoietic microenvironment (HM), we added recombinant human (rh) IL-11 to human and murine long-term bone marrow cultures (LTMC) and analyzed primitive (high proliferative potential- colony forming cells [HPP-CFC], long-term culture-initiating cells [LTC- IC], and long-term reconstituting stem cells) and progenitor (day 12 colony forming unit-spleen [CFU-S12], colony forming unit-megakaryocyte [CFU-Mk] and colony forming unit-granulocyte/macrophage [CFU-GM]) compartments throughout the duration of the cultures. rhIL-11 (100 ng/mL) added twice weekly resulted in significantly increased nonadherent (NA) cellularity, CFU-GM, and CFU-Mk production in human LTMC. Addition of rhIL-11 to murine LTMC was associated with a 5- to 40- fold increase in CFU-GM and a four- to 20-fold increase in day 12 CFU-S in NA cells. However, IL-11 had no significant effect on total HPP-CFC concentration and decreased the size of the more primitive stem/progenitor compartment as evidenced by both decreased LTC-IC frequency in human LTMC and decreased frequency of long-term reconstituting stem cells in murine LTMC. These data suggest that IL-11 may increase commitment of stem cells into a multipotential progenitor compartment. 相似文献
85.
Acquired immune hemolytic anemia associated with IgA erythrocyte coating: investigation of hemolytic mechanisms 总被引:1,自引:0,他引:1
We have investigated the hemolytic mechanisms in a patient with acquired immune hemolytic anemia whose red cells appeared to be coated with IgA alone. The clinical course was similar to that of patients with hemolytic anemia mediated by warm-reacting IgG antibody. Splenic sequestration of red cells was demonstrated, and marked reduction of hemolysis occurred after corticosteroid therapy. Antibody was eluted from the patient's red cells and used to sensitize normal red cells in vitro. These sensitized red cells were not lysed by fresh autologous serum, nor did they fix detectable amounts of C3. However, red cells sensitized by eluted antibody were lysed by normal human peripheral blood monocytes in a system designed to demonstrate antibody-dependent cell-mediated cytotoxicity. Monocyte-mediated hemolysis of sensitized red cells was inhibited by the addition of low concentrations of normal serum IgA to the system, but not by IgG. The ability of the eluate to induce monocyte-mediated hemolysis was abolished by its adsorption on Sepharose-bound anti-IgA, but not by preincubation with Sepharose-bound anti-IgG. In addition, normal human monocytes were demonstrated to ingest eluate-sensitized red cells. These data demonstrate an in vitro interaction of IgA-sensitized red cells with leukocytes and suggest a possible mechanism for the patient's hemolysis. 相似文献
86.
Purpose
There is currently a paucity of published literature focused on the treatment of infections caused by NDM-producing organisms.Methods
We describe a case of a bacteraemia caused by an extensively drug-resistant (XDR) New Delhi metallo-β-lactamase (NDM)-producing Serratia marcescens and review the treatment options for XDR NDM-producing Enterobacteriaceae.Results
Infections caused by New Delhi beta-lactamase (NDM)-producing Enterobacteriaceae are becoming increasingly prevalent worldwide. The presence of the enzyme results in multidrug-resistant and extensively drug-resistant phenotypes which often pose a treatment challenge. Despite this challenge, case reports and series have demonstrated good clinical outcomes with numerous treatment options in comparison to infections due to KPC-producing Enterobacteriaceae.Conclusions
Further good-quality research focused on the treatment of NDM-producing Enterobacteriaceae is warranted.87.
目的对比高黏度与低黏度骨水泥经皮椎体后凸成形术(PKP)治疗骨质疏松性椎体压缩性骨折(OVCF)的疗效差异。方法将2013年3月至2014年9月高要市人民医院收治的60例OVCF患者采用随机抽签法分为低黏度组(低黏度骨水泥PKP治疗)和高黏度组(高黏度骨水泥PKP治疗),每组各30例。对比两组手术前后伤椎椎体高度和后凸Cobb角;采用视觉模拟量表(VAS)评分、Oswestry功能障碍指数(ODI)、36项健康调查简表(SF-36)评分对患者疼痛程度、功能障碍和生活质量等主观感受进行评价;统计骨水泥渗漏、近期肺栓塞等并发症发生情况。结果低黏度组和高黏度组骨水泥注入量分别为(3.1±0.6)m L和(3.6±0.8)m L,两组比较,差异有统计学意义(P0.05)。术后随访3~6个月(平均4个月),两组术后1 d、3个月VAS评分、ODI、SF-36评分、伤椎椎体高度和后凸Cobb角均优于术前(P0.05),其中高黏度组术后1 d、3个月上述指标均优于低黏度组(P0.05)。低黏度组和高黏度组术后发生骨水泥渗漏、近期肺栓塞分别为6、2例和1、0例,两组并发症发生率比较,差异有统计学意义(P0.05)。结论与低黏度骨水泥比较,高黏度骨水泥PKP治疗OVCF近期疗效更为理想,骨水泥渗漏、近期肺栓塞等并发症发生率相对较低,值得临床推广应用。 相似文献
88.
目的 探讨改良颈腮腺入路在高位咽旁间隙良性肿瘤手术中的应用疗效。 方法 7例咽旁间隙良性肿瘤患者,术前影像学检查提示为高位、肿瘤巨大、哑铃型且边界欠清,采用改良颈腮腺入路术式,解剖辨认面神经总干及颞面干后,于外耳道软骨前方、腮腺的后缘以及颞面干的上方间隙向深部分离至肿瘤上极,剥离子分离并下压肿瘤与下方常规颈部自下而上肿瘤游离会师后,从颌下区取出肿瘤。腮腺浅叶不切除,面神经分支不做过多解剖。 结果 所有患者均一次性完整切除肿瘤;术后病理示多形性腺瘤6例,神经鞘瘤1例;术中出血均少于300 mL;1例患者出现术后同侧眼睑轻度闭合障碍,两周后完全正常;所有患者面容美学保存理想。 结论 对于高位咽旁间隙良性肿瘤采用改良颈腮腺入路术式,不仅可以安全完整地切除肿瘤,同时由于减少了面神经及腮腺浅叶的处置,术后相关神经并发症及腮腺区凹陷性改变的发生率下降。 相似文献
89.
AP Mishreki E Lim P Cranefield S Pascoe S Jackson DA Stell 《Annals of the Royal College of Surgeons of England》2013,95(5):349-352
Introduction
The results of surgical resection and palliative chemotherapy use in hilar cholangiocarcinoma (HC) have been well publicised but the proportion of patients able to undergo these treatments and the comparative outcomes in a population of patients with HC are less well known.Methods
Patients with HC were identified by review of all patients undergoing percutaneous cholangiography over a nine-year period (2002–2010) in a tertiary facility. The treatment undertaken and outcomes were recorded.Results
Overall, 68 patients were identified (37 female) with a median age of 70 years. Forty-five (66%) were treated solely by insertion of a metal stent (median survival 4.73 months) and nine (13%) also received palliative chemotherapy (median survival 13.7 months). Persisting jaundice after stent insertion was noted in 18 of 35 patients (51%) tested within one month of death. Fourteen patients (21%) underwent surgical resection (median survival 20.2 months).Conclusions
Patients undergoing surgical resection had significantly longer survival than those receiving only a palliative stent but not compared with those also receiving palliative chemotherapy, with short-term follow-up. Only a third of patients, however, receive active treatment (surgery or chemotherapy) and improvements in long-term biliary palliation are needed. 相似文献90.
目的评价腹膜外切口单层缝合与常规分层缝合法在化脓性或坏疽性阑尾炎术后的临床疗效。方法计算机检索Co-chrane Library、PubMed、Embase、SCI、CNKI、CBM、VIP、WANFANG DATA,纳入腹膜外切口单层缝合与常规分层缝合法在化脓性或坏疽性阑尾炎术后疗效比较的随机对照试验,对纳入研究的方法学质量进行评价,用Cochrane协作网提供的RevMan 5.1软件对数据进行统计分析,并对统计结果进行系统评价。结果共纳入6个随机对照试验,共计1 885例患者。Meta分析结果显示:腹膜外切口单层缝合与常规分层缝合法在手术时间[MD=-17.09,95%CI(-19.32,-14.87)],术后切口感染率[RR=0.06,95%CI(0.03,0.12)],7 d内出院率[RR=1.17,95%CI(1.13,1.22)]方面差异均具有统计学意义,但两者在术后疼痛程度(需应用镇痛药物比率)[RR=1.05,95%CI(0.91,1.20)]方面的差异无统计学意义。结论目前研究表明,与常规分层缝合法相比,腹膜外切口单层缝合法能显著缩短化脓性或坏疽性阑尾炎患者的手术时间,降低术后切口感染率,提高7 d内出院率,但本研究纳入的样本量小且质量不高,因此,有必要开展更多高质量、多中心的随机盲法对照试验进一步予以证实其疗效。 相似文献