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   395篇
  免费   38篇
  国内免费   2篇
耳鼻咽喉   1篇
儿科学   10篇
妇产科学   4篇
基础医学   39篇
口腔科学   15篇
临床医学   40篇
内科学   107篇
皮肤病学   9篇
神经病学   30篇
特种医学   10篇
外科学   46篇
综合类   3篇
预防医学   23篇
眼科学   8篇
药学   26篇
中国医学   1篇
肿瘤学   63篇
  2023年   13篇
  2022年   23篇
  2021年   35篇
  2020年   22篇
  2019年   23篇
  2018年   27篇
  2017年   18篇
  2016年   20篇
  2015年   25篇
  2014年   19篇
  2013年   28篇
  2012年   30篇
  2011年   46篇
  2010年   13篇
  2009年   12篇
  2008年   15篇
  2007年   8篇
  2006年   18篇
  2005年   11篇
  2004年   6篇
  2003年   11篇
  2002年   9篇
  1999年   1篇
  1983年   1篇
  1967年   1篇
排序方式: 共有435条查询结果,搜索用时 15 毫秒
1.
2.
Aims/IntroductionDiabetes mellitus is reported as a risk factor for increased coronavirus disease 2019 (COVID‐19) severity and mortality, but there have been few reports from Japan. Associations between diabetes mellitus and COVID‐19 severity and mortality were investigated in a single Japanese hospital.Materials and MethodsPatients aged ≥20 years admitted to Osaka City General Hospital for COVID‐19 treatment between April 2020 and March 2021 were included in this retrospective, observational study. Multivariable logistic regression analysis was carried out to examine whether diabetes mellitus contributes to COVID‐19‐related death and severity.ResultsOf the 262 patients included, 108 (41.2%) required invasive ventilation, and 34 (13.0%) died in hospital. The diabetes group (n = 92) was significantly older, more obese, had longer hospital stays, more severe illness and higher mortality than the non‐diabetes group (n = 170). On multivariable logistic regression analysis, age (odds ratio [OR] 1.054, 95% confidence interval [CI] 1.023–1.086), body mass index (OR 1.111, 95% CI 1.028–1.201), history of diabetes mellitus (OR 2.429, 95% CI 1.152–5.123), neutrophil count (OR 1.222, 95% CI 1.077–1.385), C‐reactive protein (OR 1.096, 95% CI 1.030–1.166) and Krebs von den Lungen‐6 (OR 1.002, 95% CI 1.000–1.003) were predictors for COVID‐19 severity (R 2 = 0.468). Meanwhile, age (OR 1.104, 95% CI 1.037–1.175) and Krebs von den Lungen‐6 (OR 1.003, 95% CI 1.001–1.005) were predictors for COVID‐19‐related death (R 2 = 0.475).ConclusionsDiabetes mellitus was a definite risk factor for COVID‐19 severity in a single Japanese hospital treating moderately‐to‐severely ill patients.  相似文献   
3.

Background

Prediction of prognosis is important for patients so that they can make the most of the rest of their lives. Oncologists could predict survival, but the accuracy of such predictions is unclear.

Methods

In this observational prospective cohort study, 14 oncologists treating 9 major adult solid malignancies were asked to complete questionnaires predicting survival based on performance status, oral intake, and other clinical factors when patients experienced progressive disease after standard chemotherapies. Clinically predicted survival (cps) was calculated by the oncologists from the date of progressive disease to the predicted date of death. Actual survival (as) was compared with cps using Kaplan–Meier survival curves, and factors affecting inaccurate prediction were determined by logistic regression analysis. The prediction of survival time was considered accurate when the cps/as ratio was between 0.67 and 1.33.

Results

The study cohort consisted of 75 patients. Median cps was 120 days (interquartile range: 60–180 days), and median as was 121 days (interquartile range: 40–234 days). The participating oncologists accurately predicted as within a 33% range 36% of the time; the survival time was overestimated 36% of time and underestimated 28% of the time. The factors affecting the accuracy of the survival estimate were the experience of the oncologist, patient age, and information given about the palliative care unit.

Conclusions

Prediction of cps was accurate for just slightly more than one third of all patients in this study. Additional investigation of putative prognostic factors with a larger sample size is warranted.  相似文献   
4.
The novel coronavirus-19 (COVID-19) pandemic has considerably impacted children’s lives. The aim of this study was to determine whether the pandemic affected mealtime regularity among preschool children and whether maintaining regular mealtimes or changes in mealtime regularity during the pandemic were related to dietary balance, including chronological relationships. This online cross-sectional survey involving individuals registered with a company that provides meals to children aged 2−6 years was conducted in February 2021. Using a 40-point scale, a healthy diet score (HDS) was developed to evaluate children’s dietary balance. The participants were divided into four groups based on their responses, and multiple regression analyses were performed with the HDS as the dependent variable. Maintaining regular mealtimes was associated with practices such as waking and going to bed earlier, less snacking, and eating breakfast every day. Even after adjusting for basic attributes, lifestyle habits, household circumstances, and other factors, regular mealtimes were still positively correlated with the HDS. These findings indicate that maintaining regular mealtimes is associated with higher HDS scores and better lifestyle habits. Furthermore, as the changed HDS was higher in the group whose mealtimes became regular during the pandemic, adopting regular mealtimes may lead to a more balanced diet.  相似文献   
5.
6.
The purpose of the current study was to investigate the mutation status of KIT in feline mast cell tumours (MCTs) and to examine the effects of tyrosine kinase inhibition on the phosphorylation of mutant kit in vitro and in clinical cases of cats. Sequence analysis of KIT identified mutations in 42/62 MCTs (67·7%). The vast majority of the mutations were distributed in exons 8 and 9, both of which encode the fifth immunoglobulin-like domain (IgD) of kit. All five types of kit with a mutation in the fifth IgD were then expressed in 293 cells and examined for phosphorylation status. The mutant kit proteins showed ligand-independent phosphorylation. The tyrosine kinase inhibitor imatinib mesylate suppressed the phosphorylation of these mutant kit proteins in transfectant cells. In a clinical study of 10 cats with MCTs, beneficial response to imatinib mesylate was observed in 7/8 cats that had a mutation in the fifth IgD of kit in tumour cells. Mutations in the fifth IgD of kit thus appear to be common and potentially sensitive to imatinib mesylate in feline MCTs. These data provide an in vivo model for paediatric mastocytosis where mutations in the fifth IgD of kit also occur.  相似文献   
7.
BackgroundClinical significance of left atrial (LA) function and geometry in patients with dilated cardiomyopathy (DCM) remains uncertain.HypothesisLA geometric parameters assessed by cardiac magnetic resonance (CMR) predict the prognosis in patients with DCM.MethodsThe present study included patients with DCM and sinus rhythm who underwent CMR between December 2007 and April 2018. LA volume was measured using CMR. LA sphericity index was computed as the ratio of the measured maximum LA volume by the volume of a sphere with maximum LA length diameter.ResultsWe included 255 patients in this study. During the mean follow‐up of 3.92 years, hospitalization for HF occurred in 37 patients. The LA sphericity index was significantly higher in patients with hospitalization for HF than in those without (0.78 ± 0.35 vs. 0.58 ± 0.18, p < .001). Multivariable Cox regression analysis identified a higher LA sphericity index as an independent predictor of hospitalization for HF. Patients were categorized based on the median of LA sphericity index. The Kaplan–Meier curve showed that patients with a high LA sphericity index (≥0.57) had a significantly higher risk of hospitalization for HF than those with a low LA sphericity index (<0.57).ConclusionLA sphericity index was an independent predictor of hospitalization for HF. Assessment of LA geometric parameters might be useful for risk stratification in patients with DCM.  相似文献   
8.
X-ray radiotherapy activates tumor antigen-specific T-cell responses, and increases in the serum levels of high mobility group box 1 (HMGB1) induced by X-ray irradiation play a pivotal role in activating anti-tumor immunity. Here, we examined whether carbon-ion beams, as well as X-rays, can induce HMGB1 release from human cancer cell lines. The study examined five human cancer cell lines: TE2, KYSE70, A549, NCI-H460 and WiDr. The proportion of cells surviving X- or carbon-ion beam irradiation was assessed in a clonogenic assay. The D10, the dose at which 10% of cells survive, was calculated using a linear–quadratic model. HMGB1 levels in the culture supernatants were assessed by an ELISA. The D10 dose for X-rays in TE2, KYSE70, A549, NCI-H460 and WiDr cells was 2.1, 6.7, 8.0, 4.8 and 7.1 Gy, respectively, whereas that for carbon-ion beams was 0.9, 2.5, 2.7, 1.8 and 3.5 Gy, respectively. X-rays and carbon-ion beams significantly increased HMGB1 levels in the culture supernatants of A549, NCI-H460 and WiDr cells at 72 h post-irradiation with a D10 dose. Furthermore, irradiation with X-rays or carbon-ion beams significantly increased HMGB1 levels in the culture supernatants of all five cell lines at 96 h post-irradiation. There was no significant difference in the amount of HMGB1 induced by X-rays and carbon-ion beams at any time-point (except at 96 h for NCI-H460 cells); thus we conclude that comparable levels of HMGB1 were detected after irradiation with iso-survival doses of X-rays and carbon-ion beams.  相似文献   
9.
Lymphangioma of the mesocolon is very rare. We report two cases of surgically resected and histologically proven mesocolic lymphangioma in adults. In both cases, ultrasound revealed a large cystic mass with multiple thin septa in the lower abdomen. A peculiar finding was the large craniocaudal sliding movement of the mass synchronized with the patient's respiration, which was a clue to the diagnosis of mesenteric lymphangioma. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46 :78–81, 2018;  相似文献   
10.
A 44-year-old man diagnosed with idiopathic dilated cardiomyopathy was admitted to our hospital with acute decompensated heart failure. Seven years before this admission, the first introduction of medication resulted in left ventricular (LV) recovery, which was sustained for several years. However, the patient stopped taking his medication, resulting in worsening of the LV function. Despite the second introduction of medication, the LV function did not improve. We performed cardiac magnetic resonance imaging and an endomyocardial biopsy, which revealed the significant development of cardiac fibrosis that had not been present at the time of the initial diagnosis.  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