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   4297篇
  免费   400篇
  国内免费   9篇
耳鼻咽喉   126篇
儿科学   310篇
妇产科学   187篇
基础医学   322篇
口腔科学   314篇
临床医学   430篇
内科学   908篇
皮肤病学   84篇
神经病学   326篇
特种医学   246篇
外科学   758篇
综合类   44篇
一般理论   1篇
预防医学   134篇
眼科学   139篇
药学   257篇
中国医学   5篇
肿瘤学   115篇
  2024年   11篇
  2023年   103篇
  2022年   69篇
  2021年   195篇
  2020年   130篇
  2019年   185篇
  2018年   261篇
  2017年   199篇
  2016年   276篇
  2015年   248篇
  2014年   318篇
  2013年   477篇
  2012年   257篇
  2011年   253篇
  2010年   214篇
  2009年   143篇
  2008年   179篇
  2007年   137篇
  2006年   159篇
  2005年   174篇
  2004年   96篇
  2003年   76篇
  2002年   76篇
  2001年   55篇
  2000年   69篇
  1999年   56篇
  1998年   53篇
  1997年   50篇
  1996年   46篇
  1995年   34篇
  1994年   24篇
  1993年   25篇
  1992年   8篇
  1991年   13篇
  1990年   10篇
  1989年   6篇
  1988年   3篇
  1985年   1篇
  1984年   2篇
  1983年   1篇
  1982年   3篇
  1980年   1篇
  1978年   3篇
  1974年   2篇
  1972年   1篇
  1962年   1篇
  1960年   1篇
  1947年   1篇
  1935年   1篇
排序方式: 共有4706条查询结果,搜索用时 15 毫秒
101.
Objective: The aim of this study was to compare maternal and fetal serum copeptin concentrations in pregnancies complicated by isolated fetal growth restriction (FGR), and uncomplicated pregnancies, and to investigate relationships between copeptin levels and clinical parameters.

Methods: Maternal and fetal serum copeptin levels were measured in 21 women with pregnancies complicated by isolated FGR and 20 women with normal pregnancies (control group). Doppler assessment of the uterine and umbilical arteries was performed in each patient.

Results: Maternal serum copeptin levels were significantly higher in women with isolated FGR compared to controls (p?=?0.042). In addition, maternal copeptin levels were inversely correlated with the uterine artery pulsatility and resistance indices and positively correlated with neonatal birth weight. Umbilical vein copeptin levels were significantly increased in neonates with adverse outcomes (p?=?0.001).

Conclusions: Increased maternal copeptin concentration may reflect a response to stress, thus serving as a compensatory mechanism in pregnancies complicated by FGR.  相似文献   

102.
103.

Background

Haematological cancer (HC) patients are increasingly requiring intensive care (ICUs). The aim of this study was to investigate the outcome of HC patients in our ICU and evaluate 5 days-full support as a breakpoint for patients’ re-assessment for support.

Methods

Retrospective study enrolling 112 consecutive HC adults, requiring ICU in January-December 2015. Patients’ data were collected from medical records and Infection Control Committee surveillance reports. Logistic regression analysis was performed to identify independent risk factors for ICU mortality.

Results

Sixty-one were neutropenic, and 99 (88%) had infection at ICU admission. Acute myeloid leukaemia was diagnosed in 43%. Thirty-five (31%) were hematopoietic stem cell transplant recipients. Only 17 (15%) were in remission. Eighty-nine underwent mechanical ventilation on admission. Fifty-three patients acquired ICU-infection (35 bacteremia) being gram negative bacteria (Klebsiella pneumoniae and non-fermenters) the top pathogens. However, ICU-acquired infection had no impact on mortality. The overall ICU and 1-year survival rate was 27% (30 patients) and 7% (8 patients), respectively. Moreover, only 2/62 patients survived with APACHE II score ≥25. The median time for death was 4 days. APACHE II score ≥25 [OR:35.20], septic shock [OR:8.71] and respiratory failure on admission [OR:10.55] were independent risk factors for mortality in multivariate analysis. APACHE II score ≥25 was a strong indicator for poor outcome (ROC under curve 0.889).

Conclusions

APACHE II score ≥25 and septic shock were criteria of ICU futility. Our findings support the full support of patients for 5 days and the need to implement a therapeutic limitations protocol.  相似文献   
104.
105.
106.

Purpose

The aim of our study is to research the role and efficacy of cerebral oximetry in predicting neurologic prognosis when applied during TTM to patients experiencing coma after CA.

Methods

This study was performed on surviving adult comatose patients after CA treated with TTM. The average scores of rSO2 was measured at 6 h intervals for the first 2 days and once a day for the following 3 days with a NIRS device during TTM. The CPC scale was used to define the neurologic outcomes of patients. We compared the correlations of rSO2 values between good (CPC 1–2) and poor (CPC 3–5) neurologic outcomes in CA patients.

Results

There was no statistically significant difference identified between the prognosis groups in terms of rSO2, CPR durations, hemoglobin values and admission body temperature (p > 0.05). When the variation in rSO2 values over time is investigated, though there was no significant difference between the good and poor prognosis groups, it appeared to fall in the first 6 h in both prognosis groups. The median NT-proBNP and lactate values were observed to be higher in the poor prognosis group.

Conclusion

There is no significant correlation between rSO2 values and neurologic outcomes. Multimodal monitoring methods may be useful and further studies with a larger patient population are necessary in this area.  相似文献   
107.
108.

AIM

To investigate the association of serum glucocorticoid kinase gene-1 (SGK-1) DNA variants with chronic central serous chorioretinopathy (CSC).

METHODS

We enrolled 32 eyes of 32 patients who were diagnosed with chronic CSC and composed 32 normal eyes as a control group. Peripheral blood was used for DNA extraction and polymerase chain reaction (PCR) amplification. SGK1 gene was sequenced by using BigDye® Terminator v3.1 cycle sequencing KIT (Applied Biosystems, Foster City, CA, USA). The SGK1 gene and its variants were investigated in CSC patient group and control group.

RESULTS

We identified a new polymorphism M32V in two person in the patient group (Minor allele frequency (MAF)=0.009) on the region of 1-60 amino acids. The rs1057293 was located in the encoder region of the SGK 1 gene but not associated with CSC (P=0.68). An intrinsic rs1743966 is also not associated (P=0.28).

CONCLUSIONS

The new polymorphism M32V is located on the region of 1-60 amino acids which is necessary for localization to the mitochondria in CSC patient. This mutation is probably important for the energy metabolism and plays an important role in the cellular response to hyperosmotic stress and other stress stimuli. Both rs1057293 and rs1743966 are not associated with CSC.  相似文献   
109.
110.

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by arterial and/ or venous thrombosis accompanied by persistently elevated levels of antiphospholipid antibodies (aPLs). The aim of this study is to evaluate the pulmonary manifestations of APS and compare the levels of aPLs in patients with and without pulmonary involvement. We retrospectively reviewed the files of patients with the diagnosis of APS between October 2010 and May 2017. Demographic data, clinical, radiological and laboratory findings were recorded. The study included 67 patients (56 female/11 male) with a mean age of 39?±?13 years. Pulmonary manifestations such as parenchymal and/or vascular involvement were seen in 12 (17.9%) patients. The patients with and without pulmonary manifestations were not significantly different in terms of age (p?=?0.46), comorbidities (p?=?0.48) and APS duration (p?=?0.66). Acute pulmonary thromboembolism (PE) was determined in 11 (16.4%), alveolar hemorrhage in 2 (3%) patients. Four patients with acute PE (36%) developed chronic thromboembolic pulmonary hypertension (CTEPH). One patient developed both CTEPH and diffuse alveolar hemorrhage after acute PE during follow up. Antiphosholipid antibody IgM was highly positive in patients with PE compared to patients without PE (p?=?0.005). Other antibodies and lupus anticoagulant were not significantly different in patients with and without PE. None of the patients were deceased due to pulmonary manifestations of APS. PE was the most common pulmonary manifestation of APS. The development of CTEPH was high among APS patients. Patients with APS should be closely followed for the onset of PE and CTEPH.

  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