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   9056篇
  免费   445篇
  国内免费   97篇
耳鼻咽喉   39篇
儿科学   138篇
妇产科学   214篇
基础医学   1483篇
口腔科学   247篇
临床医学   880篇
内科学   1656篇
皮肤病学   112篇
神经病学   983篇
特种医学   391篇
外国民族医学   1篇
外科学   897篇
综合类   334篇
预防医学   642篇
眼科学   90篇
药学   608篇
  1篇
中国医学   104篇
肿瘤学   778篇
  2023年   587篇
  2022年   765篇
  2021年   667篇
  2020年   792篇
  2019年   419篇
  2018年   305篇
  2017年   349篇
  2016年   463篇
  2015年   402篇
  2014年   780篇
  2013年   458篇
  2012年   293篇
  2011年   206篇
  2010年   382篇
  2009年   388篇
  2008年   141篇
  2007年   173篇
  2006年   143篇
  2005年   107篇
  2004年   90篇
  2003年   92篇
  2002年   114篇
  2001年   108篇
  2000年   84篇
  1999年   110篇
  1998年   135篇
  1997年   110篇
  1996年   133篇
  1995年   51篇
  1994年   47篇
  1993年   33篇
  1992年   46篇
  1991年   55篇
  1990年   56篇
  1989年   41篇
  1988年   32篇
  1987年   29篇
  1986年   37篇
  1985年   43篇
  1984年   43篇
  1983年   35篇
  1982年   36篇
  1981年   24篇
  1980年   27篇
  1979年   22篇
  1978年   18篇
  1977年   12篇
  1976年   17篇
  1975年   10篇
  1974年   16篇
排序方式: 共有9598条查询结果,搜索用时 31 毫秒
1.
AimGenomic-based ancillary assays including immunohistochemistry (IHC) for BRCA-1 associated protein-1 (BAP1) and methylthioadenosine phosphorylase (MTAP), and fluorescence in situ hybridization (FISH) for CDKN2A are effective for differentiating pleural mesothelioma (PM) from reactive mesothelial proliferations. We previously reported a combination of MTAP and BAP1 IHC effectively distinguishes sarcomatoid PM from fibrous pleuritis (FP). Nevertheless, cases of sarcomatoid PM with desmoplastic features (desmoPM) are encountered where the IHC assessment is unclear.Methods and resultsWe evaluated assessment of MTAP IHC, BAP1 IHC, and CDKN2A FISH in 20 desmoPM compared to 24 FP. MTAP and BAP1 IHC could not be assessed in 11 (55 %) and 10 (50 %) cases, respectively, due to loss or faint immunoreactivity of internal positive control cells, while CDKN2A FISH could be evaluated in all cases. The sensitivities for MTAP loss, BAP1 loss, and CDKN2A homozygous deletion in desmoPM were 40 %, 10 %, and 100 %. A combination of MTAP loss and BAP1 loss yielded 45 % of sensitivity.ConclusionsMTAP IHC is a useful surrogate diagnostic marker in differentiating ordinary sarcomatoid PM from FP, but its effectiveness is limited in desmoPM. CDKN2A FISH is the most effective diagnostic assays with 100 % sensitivity and specificity in discriminating desmoPM from FP in the facilities where the FISH assay is available.  相似文献   
2.
Autoantibodies against 3?hydroxy-3-methylglutaryl-CoA reductase (HMGCR) and the signal recognition particle (SRP) are representative antibodies causing immune-mediated necrotizing myopathies (IMNM), called as anti-HMGCR and anti-SRP myopathies, respectively. Here, we analyzed the differences in routine blood test results between 56 anti-HMGCR and 77 anti-SRP myopathy patients. A higher alanine transaminase (ALT) level and a lower aspartate transaminase (AST)/ALT ratio were observed in anti-HMGCR myopathy patients [ALT, 265.7 ± 213.3 U/L (mean ± standard deviation); AST/ALT ratio, 0.88 ± 0.32] than in anti-SRP-myopathy patients (ALT, 179.3 ± 111.2 U/L, p < 0.05; AST/ALT ratio, 1.28 ± 0.40, p < 0.01). In the active phase, anti-HMGCR myopathy often showed ALT predominance, whereas anti-SRP myopathy often showed AST predominance. In addition, there were differences in erythrocyte sedimentation rate (ESR), total cholesterol (TChol) level, and high-density lipoprotein (HDL) level between anti-HMGCR and anti-SRP myopathies (ESR: HMGCR, 24.4 ± 20.8 mm/1 h; SRP, 35.7 ± 26.7 mm/1 h, p = 0.0334; TChol: HMGCR, 226.7 ± 36.6 mg/dL; SRP, 207.6 ± 40.8 mg/dL, p = 0.0163; HDL: HMGCR, 58.4 ± 13.9 mg/dL; SRP, 46.2 ± 17.3 mg/dL, p < 0.01). Additional studies on the differences in routine blood test results may further reveal the pathomechanisms of IMNM.  相似文献   
3.
《Clinical breast cancer》2022,22(2):e232-e238
ObjectiveTo evaluate factors contributing to positive surgical margins associated with reflector guidance for patients undergoing breast conserving therapy for malignancy.Materials and MethodsA retrospective IRB-approved review of our institutional database was performed for malignant breast lesions preoperatively localized from January 1, 2018 to December 31, 2020. The following data was recorded using electronic medical records: lesion type and grade, lesion location, reflector and wire placement modality, use of intraoperative ultrasound, margin status, patient age, family history, BMI, and final pathology. Statistical analysis was performed with univariate summary statistics and logistic regression. P < .05 was significant.ResultsA total of 606 image-guided pre-surgical localizations were performed for lumpectomies of breast malignancies. A total of 352 of 606 (58%) wire localizations and 254 of 606 (42%) SCOUT reflector localizations were performed. Sixty out of 352 (17%) of wire-localized patients had positive surgical margins, whereas forty-eight out of 254 (19%) of reflector-localized patients had positive surgical margins. (OR = 1.12, P value: .59). For reflector guided cases, the use of intraoperative ultrasound (IOUS) was associated with decreased positive margin status (OR = 0 .28, 95% CI = [0.14, 0.58]) while in situ disease was associated with increased positive margin status (OR = 1.99, 95% CI = [1.05, 3.75]). No association between modality used for localization (mammography vs. ultrasound) and positive margin status was observed (OR = 0.63, 95% CI = [0.33, 1.19]). No association between positive margins and age, family history, tumor location and BMI was observed.ConclusionFor reflector guided surgeries, the use of IOUS was associated with decreased positive margins, by contrast the presence of ductal carcinoma in situ was associated with increased positive margins. There was no statistically significant difference in surgical outcomes for reflector-guided localization compared to wire localizations of the breast.  相似文献   
4.
5.
Inference of biogeographic origin is an important factor in clinical, population and forensic genetics. The information provided by AIMs (Ancestry Informative Markers) can allow the differentiation of major continental population groups, and several AIM panels have been developed for this purpose. However, from these major population groups, Eurasia covers a wide area between two continents that is difficult to differentiate genetically. These populations display a gradual genetic cline from West Europe to South Asia in terms of allele frequency distribution. Although differences have been reported between Europe and South Asia, Middle East populations continue to be a target of further investigations due to the lack of genetic variability, therefore hampering their genetic differentiation from neighboring populations. In the present study, a custom-built ancestry panel was developed to analyze North African and Middle Eastern populations, designated the ‘NAME’ panel. The NAME panel contains 111 SNPs that have patterns of allele frequency differentiation that can distinguish individuals originating in North Africa and the Middle East when combined with a previous set of 126 Global AIM-SNPs.  相似文献   
6.
7.
IntroductionPredicting pathological complete response (pCR) for patients receiving neoadjuvant chemotherapy (NAC) is crucial in establishing individualized treatment. Whole-slide images (WSIs) of tumor tissues reflect the histopathologic information of the tumor, which is important for therapeutic response effectiveness. In this study, we aimed to investigate whether predictive information for pCR could be detected from WSIs.Materials and methodsWe retrospectively collected data from four cohorts of 874 patients diagnosed with biopsy-proven breast cancer. A deep learning pathological model (DLPM) was constructed to predict pCR using biopsy WSIs in the primary cohort, and it was then validated in three external cohorts. The DLPM could generate a deep learning pathological score (DLPs) for each patient; stromal tumor-infiltrating lymphocytes (TILs) were selected for comparison with DLPs.ResultsThe WSI feature-based DLPM showed good predictive performance with the highest area under the curve (AUC) of 0.72 among the cohorts. Alternatively, the combination of the DLPM and clinical characteristics offered a better prediction performance (AUC >0.70) in all cohorts. We also evaluated the performance of DLPM in three different breast subtypes with the best prediction for the triple-negative breast cancer (TNBC) subtype (AUC: 0.73). Moreover, DLPM combined with clinical characteristics and stromal TILs achieved the highest AUC in the primary cohort (AUC: 0.82) and validation cohort 1 (AUC: 0.80).ConclusionOur study suggested that WSIs integrated with deep learning could potentially predict pCR to NAC in breast cancer. The predictive performance will be improved by combining clinical characteristics. DLPs from DLPM can provide more information compared to stromal TILs for pCR prediction.  相似文献   
8.
Abstract

Objective

The sex, age, medical history, treatment, tobacco use, race risk (SAMe-TT2R2) Score; the sex, age, medical history, treatment, tobacco use, genotype combination (SAMe-TT2G2) Score; and the so-called modified SAMe-TT2R2 scores have been proposed to predict the anticoagulation quality for patients with non-valvular atrial fibrillation (NVAF). The data from a prospective controlled study is used to validate the SAMe-TT2R2 and SAMe-TT2G2 scores in Chinese NVAF patients treated with warfarin and to evaluate the association of factors with time in therapeutic range (TTR) to predict the quality of oral anticoagulation control.  相似文献   
9.
《Ticks and Tick》2020,11(6):101540
Powassan virus (POWV) is a tickborne flavivirus discovered in Ontario, Canada in 1958 that causes long-term neurological sequelae in about half the reported cases and death in a little more than 10 % of cases. The incidence of POWV disease is rising in the United States but there is limited understanding of the scope and causes of recent changes in POWV epidemiology. We focus on quantifying the increase in human POWV disease incidence and infection prevalence in the United States. We also examine differences in the frequency of symptomatic cases and asymptomatic or mildly symptomatic cases, as well as limitations in national and state surveillance for POWV infection. We searched SCOPUS for all articles containing original POWV prevalence research, case studies, or literature reviews published in English. Case studies were supplemented by Morbidity and Mortality Weekly Report POWV data from the Centers for Disease Control and Prevention (CDC) and surveillance information from state health department websites. An increase in the number of POWV cases has been reported in the United States over the past 50 yr, and the geographic range of human POWV cases has expanded. The age distribution of symptomatic POWV cases has shifted, with significantly more individuals over 40 yr old being diagnosed after 1998. The emergence of POWV is due in large part to: (i) a change in transmission of POWV from a vector that rarely bites people (Ixodes cookei) to a new vector that often bites people (Ixodes scapularis) and has expanded its geographic range, (ii) enhanced surveillance efforts for arboviruses, and (iii) a greater awareness of POWV infection.  相似文献   
10.
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