首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2803篇
  免费   143篇
  国内免费   20篇
耳鼻咽喉   15篇
儿科学   20篇
妇产科学   19篇
基础医学   461篇
口腔科学   50篇
临床医学   273篇
内科学   476篇
皮肤病学   47篇
神经病学   187篇
特种医学   203篇
外科学   497篇
综合类   23篇
预防医学   125篇
眼科学   30篇
药学   287篇
中国医学   30篇
肿瘤学   223篇
  2024年   3篇
  2023年   25篇
  2022年   76篇
  2021年   108篇
  2020年   38篇
  2019年   78篇
  2018年   86篇
  2017年   61篇
  2016年   92篇
  2015年   137篇
  2014年   175篇
  2013年   180篇
  2012年   267篇
  2011年   242篇
  2010年   143篇
  2009年   112篇
  2008年   184篇
  2007年   142篇
  2006年   139篇
  2005年   129篇
  2004年   100篇
  2003年   83篇
  2002年   57篇
  2001年   42篇
  2000年   51篇
  1999年   40篇
  1998年   14篇
  1997年   16篇
  1996年   22篇
  1995年   6篇
  1994年   4篇
  1992年   7篇
  1991年   15篇
  1990年   9篇
  1989年   3篇
  1988年   3篇
  1987年   6篇
  1986年   5篇
  1985年   9篇
  1984年   6篇
  1983年   3篇
  1981年   3篇
  1979年   10篇
  1978年   5篇
  1977年   3篇
  1975年   3篇
  1973年   3篇
  1968年   2篇
  1967年   3篇
  1965年   2篇
排序方式: 共有2966条查询结果,搜索用时 0 毫秒
21.
We retrospectively investigated the incidence, risk factors, and outcomes of SOS (sinusoidal obstruction syndrome; previously veno-occlusive disease [VOD]) after allogeneic hematopoietic stem cell transplantation (alloHSCT) in aplastic anemia. Two hundred and sixty patients were included in the analysis. SOS developed in 7.3% (n = 19/260) of patients. Classical Cy (200 mg/m2)-ATG was the most common conditioning regimen (84.2%) in the SOS group. The SOS mortality rate was 4/19 (21.1%). Univariate analyses revealed that Cy 200 mg/m2 conditioning (p = 0.035), classical Cy-ATG conditioning (p = 0.007), and horse ATG conditioning (p < 0.001) were significant risk factors for developing SOS. Multivariate analysis revealed that only horse ATG conditioning was a poor prognostic factor (HR = 3.484; 95% CI 1.226–9.904; p = 0.002). Rabbit ATG (HR 12.719; 95% CI 2.332–69.373; p = 0.003) and weight gain > 10% (HR 35.655; 95% CI 2.208–575.805; p = 0.012) were risk factors in the overall SOS group. Both rabbit ATG conditioning and weight gain of more than 10% were associated with poor overall survival with a median of 1.2 months (5Y survival rate, any risk factor vs. none: 74.6% vs. 0.0%; p < 0.001; Fig. 2) in the SOS group.  相似文献   
22.
Objectives:This study aimed to analyze the associations of income, marital status, and health behaviors with hypertension in male and female over 40 years of age in the Korea.Methods:The data were derived from the Korean Genome and Epidemiology Study (KoGES; 4851-302) which included 211 576 participants. To analyze the relationships of income, marital status, and health behaviors with hypertension in male and female over 40 years of age, multiple logistic regression was conducted with adjustments for these variables.Results:The prevalence of hypertension increased linearly as income decreased. The odds ratio for developing hypertension in people with an income of <0.5 million Korean won (KRW) compared to ≥6.0 million KRW was 1.55 (95% confidence interval [CI], 1.25 to 1.93) in the total population, 1.58 (95% CI, 1.27 to 1.98) in male, and 1.07 (95% CI, 0.35 to 3.28) in female. The combined effect of income level and marital status on hypertension was significant. According to income level and marital status, in male, low income and divorce were most associated with hypertension (1.76 times; 95% CI, 1.01 to 3.08). However, in female, the low-income, married group was most associated with hypertension (1.83 times; 95% CI, 1.71 to 1.97).Conclusions:The results of this study show that it is necessary to approach male and female marital status separately according to income in health policies to address inequalities in the prevalence of hypertension.  相似文献   
23.
Progressive brain atrophy is a key neuropathological hallmark of Alzheimer''s disease (AD) dementia. However, atrophy patterns along the progression of AD dementia are diffuse and variable and are often missed by univariate methods. Consequently, identifying the major regional atrophy patterns underlying AD dementia progression is challenging. In the current study, we propose a method that evaluates the degree to which specific regional atrophy patterns are predictive of AD dementia progression, while holding all other atrophy changes constant using a total sample of 334 subjects. We first trained a dense convolutional neural network model to differentiate individuals with mild cognitive impairment (MCI) who progress to AD dementia versus those with a stable MCI diagnosis. Then, we retested the model multiple times, each time occluding different regions of interest (ROIs) from the model''s testing set''s input. We also validated this approach by occluding ROIs based on Braak''s staging scheme. We found that the hippocampus, fusiform, and inferior temporal gyri were the strongest predictors of AD dementia progression, in agreement with established staging models. We also found that occlusion of limbic ROIs defined according to Braak stage III had the largest impact on the performance of the model. Our predictive model reveals the major regional patterns of atrophy predictive of AD dementia progression. These results highlight the potential for early diagnosis and stratification of individuals with prodromal AD dementia based on patterns of cortical atrophy, prior to interventional clinical trials.  相似文献   
24.
Circulating xanthine oxidoreductase (XOR) activity may contribute to the pathogenesis of obesity-related adverse cardiometabolic profiles. This pilot study aimed to examine the cross-sectional associations between plasma XOR activity and cardiometabolic risk (CMR) markers in overweight and obese men. In 64 overweight and obese Japanese men (aged 31–63 years), plasma XOR activity and several CMR markers, such as homeostasis model assessment of insulin resistance (HOMA-IR), and clustered CMR score were measured in each participant. Clustered CMR score was constructed based on waist circumference, triglyceride, blood pressure, fasting plasma glucose, and high-density lipoprotein cholesterol. Plasma XOR activity in overweight and obese men was positively associated with the body mass index, waist circumference, visceral fat area, body fat mass, hemoglobin A1c, serum 8-hydroxy-2''-deoxyguanosine, HOMA-IR, and clustered CMR score and was inversely associated with handgrip strength and high-density lipoprotein cholesterol. Multiple linear regression analysis further demonstrated that the associations of plasma XOR activity with HOMA-IR and the clustered CMR score remained significant after adjustment for covariates including uric acid. Our data demonstrate that circulating XOR activity was independently associated, albeit modestly, with HOMA-IR and the clustered CMR score. These preliminary findings suggest that circulating XOR activity can potentially be one of the preventive targets and biomarkers of cardiometabolic disorders in over­weight and obese men.  相似文献   
25.
Background:The purpose of this study was to investigate the effects of the meditation-based intervention on obsessive-compulsive disorder (OCD).Methods:The following databases were searched up to April 2021: the Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE, Medline (via PubMed), PsycARTICLES, 4 Korean databases (Korean Medical Database [KMbase], Koreanstudies Information Service System [KISS], National Digital Science Library [NDSL], and Oriental Medicine Advanced Searching Integrated System [OASIS]), and China National Knowledge Infrastructure (CNKI). The search terms related to meditation-based intervention and OCD were used. This systematic review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The selected articles were evaluated using the Cochrane risk of bias tool. The Review Manager (RevMan) 5.4 was used to perform the meta-analysis.Results:In all, 16 randomized controlled trials were selected. The meta-analysis showed that the group receiving the treatment combining medication and meditation-based intervention for OCD showed a more significant post-treatment improvement in Yale-Brown obsessive compulsive scale than the group receiving medication only. Compared with other non-medication interventions that are known to be effective in treating OCD, the Yale-Brown obsessive compulsive scale showed a significant improvement immediately after the meditation-based intervention. However, no significant difference was found in the follow-up monitoring data across all examined cases.Conclusion:This study was conducted to verify the effects of meditation-based intervention on OCD. The results suggested that combined treatment with medication and meditation-based intervention was more effective in treating OCD than medication alone; the positive effects of meditation-based intervention may be greater than the effects of other non-medication interventions. However, the lack of significant difference in the follow-up indicates that long-term effect of meditation-based interventions is unclear.Trial registration number:PROSPERO CRD42021244408  相似文献   
26.
The aim the study was to determine the effect of SonoPrep? on the delivery and analgesic effects of EMLA? cream prior to intravenous (iv) cannulation in a tertiary pediatric emergency department. Children aged between 5 and 10?years were enrolled. Patients were randomized to receive either sonophoresis with SonoPrep? or sham sonophoresis followed by application of EMLA? cream for 5?min prior to iv cannulation. The primary outcome measurement was the child's rating of pain immediately after iv placement, using a 10-cm visual analog scale (VAS). Parents or guardians and blinded researchers were additionally asked to rate their perception of the child's pain using the 10-cm VAS and the Wong-Baker Face scale. A total of 42 patients completed the study (21 in the study group, 21 in the control group). The baseline characteristics between the groups were similar. The VAS pain score was significantly lower in children treated with sonophoresis compared with the sham sonophoresis (median (percentiles 25th-75th), 20.0 (10.0-22.5) vs. 60.0 (31.0-87.5); p?相似文献   
27.
Lower extremity revascularization (LER) for peripheral artery disease in elderly patients is associated with a high risk of perioperative morbidity and mortality. This study aimed to a conduct retrospective review and propensity score matching analysis to determine whether the use of regional anesthesia (RA) instead of general anesthesia (GA) in geriatric patients undergoing LER for peripheral artery disease results in improved short-term mortality and health outcomes. We reviewed medical records of 1271 patients aged >65 years who underwent LER at our center between May 1998 and February 2016. According to the anesthesia method, patients were grouped in the GA and RA groups. The primary outcome was short-term mortality (7-day and 30-day). The secondary outcomes were 5-year survival rate, intraoperative events, postoperative morbidity, and postoperative length of stay. A propensity score-matched cohort design was used to control for potentially confounding factors including patient demographics, comorbidities, American Society of Anesthesiologists physical status, and preoperative medications. After propensity score matching, 722 patients that received LER under GA (n = 269) or RA (n = 453) were identified. Patients from the GA group showed significantly higher 7-day mortality than those from the RA group (5.6% vs 2.7% P = .048); however, there was no significant difference in 30-day mortality between the groups (GA vs RA: 6.3% vs 3.6%, P = .083). The 5-year survival rate and incidence of arterial and central venous catheter placement or intraoperative dopamine and epinephrine use were significantly higher in the GA group than in the RA group (P < .05). In addition, the frequency of immediate postoperative oxygen therapy or mechanical ventilation support was higher in the GA group (P < .05). However, there was no difference in the postoperative cardiopulmonary and cerebral complications between the 2 groups. These results suggest that RA can reduce intraoperative hemodynamic support and provide immediate postoperative respiratory intensive care. In addition, the use of RA may be associated with better short-term and 5-year survival rates in geriatric patients undergoing LER.  相似文献   
28.
29.
PurposeThe estimated glomerular filtration rate (eGFR) at 6 months after donation (eGFR6m) is strongly associated with the risk of end-stage renal disease in living kidney donors. This study aimed to investigate the incidence of eGFR6m <60 mL/min/1.73 m2 (eGFR6m <60) and identify the risk factors that can predict the occurrence of eGFR6m <60 in living kidney donors.Materials and MethodsLiving kidney donors who underwent nephrectomy at Severance Hospital between January 2009 and December 2019 were identified. We excluded 94 of 1233 donors whose creatinine values at 6 months after donation were missing. The risk factors for eGFR6m <60 were assessed using multivariate regression analysis. The optimal cutoff points for candidate risk factors for predicting eGFR6m <60 occurrence were determined using the Youden index.ResultsThe eGFR6m <60 occurred in 17.3% of the participants. Older age (≥44 years), history of hypertension, lower preoperative eGFR (<101 mL/min/1.73 m2), and degree of increase in creatinine levels on postoperative day 2 compared to those before surgery (ΔCr2_pre) (≥0.39 mg/dL) increased the risk of eGFR6m <60. The addition of ΔCr2_pre to preoperative eGFR yielded a higher predictive accuracy for predicting eGFR6m <60 than that with preoperative eGFR alone {area under the receiver operating characteristic curve=0.886 [95% confidence interval (CI), 0.863–0.908] vs. 0.862 (95% CI, 0.838–0.887), p<0.001}.ConclusionThe incidence of eGFR6m <60 was 17.3%. Older age, lower preoperative eGFR, history of hypertension, and greater ΔCr2_pre were associated with the occurrence of eGFR6m <60 after living donor nephrectomy. The combination of preoperative eGFR and ΔCr2_pre showed the highest predictive power for eGFR6m <60.  相似文献   
30.
Background and PurposeAmyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease. Selective deficiency of edited adenosine deaminase acting on RNA 2 (ADAR2), a key molecule in the acquisition of Ca2+ resistance in motor neurons, has been reported in sporadic ALS (sALS) spinal motor neurons. Since ADAR2 activity is positively regulated by prolyl isomerase Protein never in mitosis gene A interacting-1 (Pin1), a known phosphorylation-dependent peptidyl-prolyl cis/trans isomerase, we investigated Pin1 expression in spinal motor neurons in sALS.MethodsSpecimens of the spinal cord were obtained from the lumbar region in eight sALS patients and age-matched five controls after postmortem examinations. The specimens were double stained with anti-Pin1 and anti-TAR DNA-binding protein of 43 kDa (TDP-43) antibodies, and examined under a fluorescence microscope.ResultsThis study analyzed 254 and 422 spinal motor neurons from 8 sALS patients and 5 control subjects, respectively. The frequency of motor neurons with high cytoplasmic Pin1 expression from the spinal cord did not differ significantly between sALS specimens without cytoplasmic TDP-43 inclusions and control specimens. However, in sALS specimens, neurons for which the Pin1 immunoluminescence intensity in the cytoplasm was at least twice that in the background were more common in specimens with cytoplasmic TDP-43 inclusions (p<0.05 in χ2 test).ConclusionsIn sALS, neurons with higher expression levels of Pin1 levels had more TDP-43 inclusions. Despite the feedback mechanism between Pin1 and ADAR2 being unclear, since Pin1 positively regulates ADAR2, our results suggest that higher Pin1 expression levels in motor neurons with TDP-43 pathology from sALS patients represent a compensatory mechanism.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号