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71.
The regulation of erythropoiesis is primarily controlled by erythropoietin (Ep). Recently, however, other factors that both stimulate and inhibit erythropoiesis have been reported. Using an in vitro liquid culture of bone marrow cells, a factor in normal mouse serum was demonstrated that markedly stimulated heme synthesis by marrow erythroid cells. In this study, the role of this heme synthesis stimulating factor (HSF) and Ep in the erythropoietic suppression caused by endotoxin administration to mice was examined. Although HSF levels did not alter appreciably after endotoxin injection, marrow erythroid cells from these animals became unresponsive to the factor. This could be reversed if Ep was added to the culture in vitro or if the hormone was injected into the mice 18 hr prior to harvesting the marrow. This marrow erythroid cell response is identical to that seen in animals in whom Ep levels are markedly reduced, such as that found in exhypoxic polycythemia, and suggest a decrease in the hormone following endotoxin administration. Additional studies demonstrated that when Ep was injected into mice 6 hr after endotoxin administration, an increase in femoral erythroid colony-forming units (CFU-E), proerythroblast number, and 59 Fe incorporation into femoral marrow cells could be demonstrated. These findings, together with the marrow erythroid cell response to the hormone, suggest that the mechanism for suppression of erythropoiesis after endotoxin injection is a reduction in the level of circulating Ep. 相似文献
72.
ProMACE/CytaBOM方案治疗难治性或复发性非霍奇金淋巴瘤的疗效观察 总被引:5,自引:0,他引:5
目的:探讨ProMACE/CytaBOM方案治疗难治性和(或)复发性非霍奇金淋巴瘤(NHL)的疗效。方法:采用ProMACE/CytaBOM方案治疗18例难治性和(或)复发性NHL患者,其中难治性NHL患者8例,复发性NHL患者10例。结果:5例难治性和(或)复发性NHL患者达到完全缓解(CR率为27.8%),4例达部分缓解(PR率为22.2%),总有效率为50.0%;目前12例仍生存,其中生存最长者26个月(2例),仍处于CR期。毒副作用主要为消化道症状、轻度肝功能异常以及骨髓抑制。结论:ProMACE/CytaBOM方案对部分难治性和(或)复发性NHL患者仍有效,毒副作用较轻,可用于治疗对其他化疗方案无效的难治性和(或)复发性NHL。 相似文献
73.
An’Nita C. Moore-Hebron Shavon Darden Darlene V. Hinds-Jackson 《The Journal for Nurse Practitioners》2018,14(10):e217-e225
With adolescents and young adults constituting a large percentage of sexually transmitted infection cases in the United States, providers serving this population are often required to manage suspected and confirmed cases. Unique presentations may prove challenging when considering empiric treatment, possible diagnostic culprits, and management of patients at risk for loss to follow-up. Additionally, concerns regarding the appropriateness of human immunodeficiency virus pre-exposure or postexposure prophylaxis can confound care strategies. This case describes an atypical encounter involving a college student. It highlights the importance of prompt and effective care of genitourinary complaints in college health settings. 相似文献
74.
Jacques DA Ndawinz Xavier Anglaret Eric Delaporte Sinata Koulla-Shiro Delphine Gabillard Albert Minga Dominique Costagliola Virginie Supervie 《Bulletin of the World Health Organization》2015,93(8):521-528
Objective
To propose two new indicators for monitoring access to antiretroviral treatment (ART) for human immunodeficiency virus (HIV); (i) the time from HIV seroconversion to ART initiation, and (ii) the time from ART eligibility to initiation, referred to as delay in ART initiation. To estimate values of these indicators in Cameroon.Methods
We used linear regression to model the natural decline in CD4+ T-lymphocyte (CD4+ cell) numbers in HIV-infected individuals over time. The model was fitted using data from a cohort of 351 people in Côte d’Ivoire. We used the model to estimate the time from seroconversion to ART initiation and the delay in ART initiation in a representative sample of 4154 HIV-infected people who started ART in Cameroon between 2007 and 2010.Findings
In Cameroon, the median CD4+ cell counts at ART initiation increased from 140 cells/μl (interquartile range, IQR: 66 to 210) in 2007–2009 to 163 cells/μl (IQR: 73 to 260) in 2010. The estimated average time from seroconversion to ART initiation decreased from 10.4 years (95% confidence interval, CI: 10.3 to 10.5) to 9.8 years (95% CI: 9.6 to 10.0). Delay in ART initiation increased from 3.4 years (95% CI: 3.1 to 3.7) to 5.8 years (95% CI: 5.6 to 6.2).Conclusion
The estimated time to initiate ART and the delay in ART initiation indicate that progress in Cameroon is insufficient. These indicators should help monitor whether public health interventions to accelerate ART initiation are successful. 相似文献75.
Seelwan Sathitratanacheewin Ruth A. Engelberg Lois Downey Robert Y. Lee James A. Fausto Helene Starks Ben Dunlap James Sibley William Lober Elizabeth T. Loggers Nita Khandelwal J. Randall Curtis 《Journal of pain and symptom management》2018,55(1):75-81
Context
Recent analyses of Medicare data show decreases over time in intensity of end-of-life care. Few studies exist regarding trends in intensity of end-of-life care for those under 65 years of age.Objectives
To examine recent temporal trends in place of death, and both hospital and intensive care unit (ICU) utilization, for age-stratified decedents with chronic, life-limiting diagnoses (<65 vs. ≥65 years) who received care in a large healthcare system.Methods
Retrospective cohort using death certificates and electronic health records for 22,068 patients with chronic illnesses who died between 2010 and 2015. We examined utilization overall and stratified by age using multiple regression.Results
The proportion of deaths at home did not change, but hospital admissions in the last 30 days of life decreased significantly from 2010 to 2015 (hospital b = ?0.026; CI = ?0.041, ?0.012). ICU admissions in the last 30 days also declined over time for the full sample and for patients aged 65 years or older (overall b = ?0.023; CI = ?0.039, ?0.007), but was not significant for younger decedents. Length of stay (LOS) did not decrease for those using the hospital or ICU.Conclusion
From 2010 to 2015, we observed a decrease in hospital admissions for all age groups and in ICU admissions for those over 65 years. As there were no changes in the proportion of patients with chronic illness who died at home nor in hospital or ICU LOS in the last 30 days, hospital and ICU admissions in the last 30 days may be a more responsive quality metric than site of death or LOS for palliative care interventions. 相似文献76.
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
77.
ABSTRACTIntroduction: Treatment options for COPD have evolved rapidly in the last decade and inhaled bronchodilators have largely supplanted the use of oral bronchodilators because of their increased efficacy and excellent safety with topical delivery to the lung. Recently added to the therapeutic armamentarium are fixed-dose combinations (FDC) of two long acting bronchodilators. LAMAs (long acting muscarinic antagonists) and LABAs (long acting beta agonists) are the main classes available and use different pathways to effectively produce bronchial smooth muscle relaxation.Areas covered: The most recent inhaled FDC LAMA/LABA to come to market is Aclidinium Bromide and Formoterol Fumarate. We searched databases of PubMed, Cochrane Library, and manufacturers’ websites and retrieved all the randomized-controlled trials (RCTs) conducted with these drugs up to September 2019.Expert opinion: It is likely that FDCs will become the core of our COPD pharmacotherapy for all but the mildest COPD patients. These individual drugs have excellent efficacy and safety records for the maintenance treatment of COPD. Studies have demonstrated that twice daily treatment with aclidinium/formoterol resulted in significant improvement in lung function and an improved exercise tolerance when compared to placebo. Adverse effects are within the range of what is seen with other LAMA/LABA combinations. 相似文献
78.
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
79.
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
80.
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