全文获取类型
收费全文 | 8317篇 |
免费 | 326篇 |
国内免费 | 50篇 |
学科分类
医药卫生 | 8693篇 |
出版年
2024年 | 2篇 |
2023年 | 70篇 |
2022年 | 68篇 |
2021年 | 240篇 |
2020年 | 136篇 |
2019年 | 167篇 |
2018年 | 204篇 |
2017年 | 179篇 |
2016年 | 276篇 |
2015年 | 318篇 |
2014年 | 433篇 |
2013年 | 509篇 |
2012年 | 644篇 |
2011年 | 596篇 |
2010年 | 407篇 |
2009年 | 417篇 |
2008年 | 606篇 |
2007年 | 671篇 |
2006年 | 589篇 |
2005年 | 596篇 |
2004年 | 505篇 |
2003年 | 432篇 |
2002年 | 339篇 |
2001年 | 48篇 |
2000年 | 25篇 |
1999年 | 24篇 |
1998年 | 41篇 |
1997年 | 27篇 |
1996年 | 32篇 |
1995年 | 23篇 |
1994年 | 12篇 |
1993年 | 9篇 |
1992年 | 12篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1980年 | 2篇 |
1974年 | 1篇 |
1970年 | 3篇 |
1966年 | 1篇 |
排序方式: 共有8693条查询结果,搜索用时 437 毫秒
91.
Ozkara A Cetin G Mert M Akinci O Erdem CC Suzer K 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2005,32(2):151-153
We report a case of successful reoperation for aortic arch dissection with use of the "arch-first" technique in a patient who had Marfan syndrome. Extracorporeal circulation was initiated via right subclavian artery cannulation, and the chest was entered through a clamshell incision for the best exposure. When the patient was cooled to 18 degrees C, the perfusion was stopped. After the 1st aortic arch anastomosis to a 30-mm Dacron graft, cerebral perfusion was reestablished via the right subclavian artery. The aortic repair was then completed. The cerebral ischemic time was 18 minutes, the aortic cross-clamp time was 69 minutes, and the total extracorporeal circulation time was 334 minutes. The patient was discharged from the hospital on postoperative day 10 with no neurologic impairment. The arch-first technique shortens the duration of brain ischemia. When combined with a clamshell incision, the technique is particularly helpful for reoperation of the aortic arch and thoracic aorta. 相似文献
92.
Mehmet?DoganEmail authorView authors OrcID profile Tolga?Han?Efe Tolga?Cimen Cem?Ozisler Mehmet?Ali?Felekoglu Ahmet?Goktug?Ertem Mehmet?Erat Omer?Yiginer Murat?Tulmac 《Lung》2018,196(2):173-178
Objectives
Systemic sclerosis (SSc) is a chronic, inflammatory, and autoimmune connective tissue disease that is associated with vascular lesions, and fibrosis of the skin and visceral organs. Cardiac complications may occur as a secondary effect of SSc as a result of pulmonary arterial hypertension and interstitial lung disease. The objective of this study was to assess whether the pulmonary pulse transit time (pPTT) could serve as a diagnostic marker for pulmonary arterial alterations in patients with SSc, prior to development of pulmonary hypertension.Methods
Twenty-five SSc patients as a study group and 25 age- and sex-matched healthy volunteers for the control group were recruited to the study. Right ventricle function parameters, such as tricuspid annular plane systolic excursion (TAPSE), estimated pulmonary artery systolic pressure (ePASP), right ventricular dimensions, right ventricle fractional area changes, and myocardial perfusion index (MPI) were measured and calculated. Pulmonary pulse transit time was defined as the time interval between the R-wave peak in the ECG and the corresponding peak late systolic pulmonary vein flow velocity.Results
Right ventricle myocardial performance index (RVMPI) and eSPAP were significantly higher in the SSc group than the controls (p?=?0.032, p?=?0.012, respectively). Pulmonary pulse transit time and TAPSE was shorter in the patients with SSc (p?=?0.006, p?=?0.015, respectively). In correlation analysis, pPTT was inversely correlated with RVMPI (r?=???0.435, p?=?0.003), eSPAP (r?=???0.434, p?=?0.003), and disease duration (r?=???0.595, p?=?0.003). Conversely, it positively correlated with TAPSE (r?=?0.345, p?=?0.022).Conclusion
pPTT was found to be shorter in SSc patients. pPTT might serve as a surrogate marker of pulmonary hemodynamics in patients with SSc, even prior to the development of pulmonary hypertension.93.
Tugba Mandal Şenay Aydın Dilek Kanmaz Ahmet Levent Karasulu Gülfidan Aras Esin Tuncay 《Sleep & breathing》2016,20(3):1021-1027
Aim
Willis-Ekbom disease (RLS/WED) is common in chronic obstructive pulmonary disease (COPD). Patients with RLS/WED have poorer quality of sleep and more fatigue and depressive symptoms. The prevalence of RLS/WED in patients with COPD has been reported to vary between 29.1 and 36.8 %. However, during exacerbation, the prevalence can increase up to 54 %. These rates are higher than those seen in general population. We have not enough knowledge regarding the association between RLS and COPD. In this study, we aimed to determine the frequency of RLS in patients with stable COPD without comorbid conditions. In addition, we also aimed to determine possible related causative factors.Method
We included 80 COPD patients without comorbid conditions who presented to our outpatient clinic between April 2013 and September 2013 for RLS/WED evaluation. Three cases that have polyneuropathy and one case that refused undergoing electromyography (EMG) examination were excluded from the study. Demographic data, P-A chest X-rays, pulmonary function tests (PFT), biochemical parameters (including hemogram), and dyspnea scales were evaluated for each patient. In addition, the RLS/WED rating scale and Epworth Sleep Scale (ESS) were applied. Further, each patient diagnosed with RLS/WED underwent a detailed neurological examination (performed by a neurologist) and an EMG examination to rule out polyneuropathy.Results
Out of 76 COPD cases included in our study, 26.3 % (n?=?20) were diagnosed with RLS/WED (mean age 60.4?±?7.5 years, 20 males). The cases with RLS/WED had significantly lower body mass index (BMI) than cases without RLS/WED (p?=?0.009). There were no significant differences between cases with and without RLS/WED with respect to PFT, dyspnea scales, and arterial blood gas values. However, ESS was significantly different (p?=?0.016). There were no significant differences in RLS/WED scores and mean hs-CRP levels between COPD stages (p?=?0.424; p?=?0.518, respectively), while ESS was significantly different (p?=?0.016). ESS was significantly higher in stage B COPD than in stages A and D (p?=?0.005, p?=?0.008, respectively). Based on our model, we found that exacerbations and iron binding capacity (UIBC) were predictive factors for RLS/WED (p?<?0.100)Conclusion
RLS/WED is a common disease in cases with stable COPD. Despite our hypothesis suggesting that the prevalence of RLS/WED in COPD is related with systemic inflammation, we did not find a significant association between hs-CRP and COPD cases with RLS/WED. However, we did find that UIBC is a predictive factor for the development of RLS/WED. Nonetheless, further studies are needed to understand the relationships between UIBC, low BMI, and the development of RLS/WED in COPD.94.
Bulent Cakmak Ahmet Inanir Mehmet Can Nacar 《The journal of maternal-fetal & neonatal medicine》2015,28(7):819-822
Objective: To assess postural balance in females with pregnancies complicated by hyperemesis gravidarum (HG).Methods: In this observational study, postural balance during the first trimester was measured using the Biodex Balance System (BBS) in 41 pregnant females (20 females with pregnancies complicated by HG and 21 healthy controls). The overall stability index (OA), anterior-posterior stability index (APSI), medial-lateral stability index (MLSI) and fall risk test (FRT) scores were obtained from the mean scores of three trials on the BSS. The four measurements obtained from the BBS (OA, APSI, MLSI and FRT) were compared between healthy pregnant females and those with pregnancies complicated by HG (HG group).Results: The mean OA and APSI scores were significantly higher in the HG group compared to healthy pregnant controls (p?0.01). There was no significant difference in the MLSI between the two groups (p?>?0.05). The FRT scores of HG patients were higher than healthy pregnant females (p?=?0.001).Conclusions: Pregnant females with HG have poor postural stability/balance and high fall risk test scores. HG causes decreased postural equilibrium in the first trimester of pregnancy. 相似文献
95.
Novel oncogene and tumor suppressor mutations in KIT and PDGFRA wild type gastrointestinal stromal tumors revealed by next generation sequencing
下载免费PDF全文
![点击此处可从《Genes, chromosomes & cancer》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jaclyn Frances Hechtman Ahmet Zehir Talia Mitchell Laetitia Borsu Samuel Singer William Tap Alifya Oultache Marc Ladanyi Khedoudja Nafa 《Genes, chromosomes & cancer》2015,54(3):177-184
Among gastrointestinal stromal tumors (GISTs) of 10–15% are negative for KIT and PDGFRA, and most of these cases are SDH deficient. Recent studies have provided data on additional molecular alterations such as KRAS in KIT mutant GISTs. We aimed to assess the frequency and spectrum of somatic mutations in common oncogenes as well as copy number variations in GISTs negative for KIT and PDGFRA mutations. GISTs with wild type KIT/PDGFRA were tested via next generation sequencing for somatic mutations in 341 genes. SDHB immunohistochemistry to evaluate for SDH deficiency was also performed. Of 267 GISTs tested for KIT and PDGFRA mutations, 15 were wild type, of which eight cases had material available for further testing. All eight cases had loss of SDHB expression and had various molecular alterations involving ARID1A, TP53, and other genes. One case had a KRAS G12V (c.35G>T) mutation in both the primary gastric tumor and a post‐imatinib recurrence. This tumor had anaplastic features and was resistant to multiple tyrosine kinase inhibitors, ultimately resulting in cancer‐related mortality within 2 years of diagnosis. In conclusion, KRAS mutations occur in rare GISTs with wild type KIT and PDGFRA. These tumors may display immunohistochemical positivity for KIT and primary resistance to tyrosine kinase inhibitors. © 2014 Wiley Periodicals, Inc. 相似文献
96.
Consistent copy number changes and recurrent PRKAR1A mutations distinguish Melanotic Schwannomas from Melanomas: SNP‐array and next generation sequencing analysis
下载免费PDF全文
![点击此处可从《Genes, chromosomes & cancer》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Lu Wang Ahmet Zehir Justyna Sadowska Nengyi Zhou Marc Rosenblum Klaus Busam Narasimhan Agaram William Travis Maria Arcila Snjezana Dogan Michael F. Berger Donavan T. Cheng Marc Ladanyi Khedoudja Nafa Meera Hameed 《Genes, chromosomes & cancer》2015,54(8):463-471
Melanotic Schwannomas (MS) are rare tumors that share histological features with melanocytic tumors and schwannomas. However, their genetics are poorly understood. To elucidate the genetic characteristics of MS, we performed genome‐wide studies in a series of cases. Twelve MS cases were available for the study. Genomic DNAs extracted from formalin‐fixed paraffin embedded tumor tissues were subjected to copy number (CN) and allelic imbalance (AI) analysis by Single Nucleotide Polymorphism (SNP)‐array and screened for mutations in coding exons of 341 key cancer‐associated genes using a hybrid capture‐based next‐generation sequencing (NGS) assay. Sanger sequencing was used to further verify recurrent mutations detected by NGS study. SNP‐array analysis revealed remarkably stereotypic chromosomal abnormalities in MS. Hypodiploidy was common, typically involving monosomies of chromosomes 1, 2, and 17. All 12 samples showed mutations in PRKAR1A gene, including 2 cases with 2 mutations each. The 14 mutations were scattered across PRKAR1A, and most were inactivating mutations. AI on 17q, presenting as loss of heterozygosity with or without CN losses, combined with a PRKAR1A mutation was observed in 9/12 MS cases. The remaining 3 cases included the two samples harboring two mutations in PRKAR1A. MS exhibits a stereotypic pattern of chromosomal losses. In contrast, melanomas are typically characterized by the presence of multiple CN aberrations, without demonstrable differences in the frequency of losses and gains. Inactivation of both alleles of PRKAR1A by “two hits” observed in almost all cases underscores the central role of PRKAR1A in the pathogenesis of this neoplasm. © 2015 Wiley Periodicals, Inc. 相似文献
97.
Mert İlker Hayıroğlu Muhammed Keskin Ahmet Okan Uzun Emrah Bozbeyoğlu Özlem Yıldırımtürk Ömer Kozan Seçkin Pehlivanoğlu 《The international journal of cardiovascular imaging》2018,34(3):329-336
SYNTAX Score II (SSII) connects clinical variables with coronary anatomy. We investigated the prognostic value of SSII in patients with ST segment elevated myocardial infarction (STEMI) complicated with cardiogenic shock treated with primary percutaneous coronary intervention (PPCI). In this retrospective analysis, we evaluated the in-hospital prognostic impact of SSII on 492 patients with STEMI complicated with cardiogenic shock treated with PPCI. Patients were stratified by tertiles of SSII, in-hospital clinical outcomes were compared between those groups. In-hospital univariate analysis revealed higher rates of in-hospital death for patients with SSII in tertile 3, as compared to patients with SSII in tertile 1 (OR 17.4, 95% CI 10.0–30.2, p?<?0.001). After adjustment for confounding baseline variables, SSII in tertile 3 was associated with 6.2-fold hazard of in-hospital death (OR 6.2, 95% CI 2.6–14.1, p?<?0.001). SSII in patients with STEMI complicated with cardiogenic shock treated with PPCI provide an independent prognostic marker of in-hospital outcomes. Our data suggests SSII to be a simple, feasible and clinically applicable tool for rapid risk stratification in patients with STEMI complicated with cardiogenic shock treated with PPCI. 相似文献
98.
99.
Is real‐time elastography helpful to differentiate acute from subacute deep venous thrombosis? A preliminary study
下载免费PDF全文
![点击此处可从《Journal of clinical ultrasound : JCU》网站下载免费的PDF全文](/ch/ext_images/free.gif)
100.