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   601篇
  免费   19篇
  国内免费   2篇
耳鼻咽喉   21篇
儿科学   25篇
妇产科学   47篇
基础医学   69篇
口腔科学   1篇
临床医学   55篇
内科学   112篇
神经病学   71篇
特种医学   11篇
外科学   36篇
综合类   8篇
预防医学   45篇
眼科学   44篇
药学   65篇
中国医学   1篇
肿瘤学   11篇
  2021年   1篇
  2020年   4篇
  2019年   5篇
  2018年   12篇
  2017年   15篇
  2016年   9篇
  2015年   11篇
  2014年   25篇
  2013年   27篇
  2012年   41篇
  2011年   54篇
  2010年   24篇
  2009年   8篇
  2008年   40篇
  2007年   56篇
  2006年   70篇
  2005年   51篇
  2004年   54篇
  2003年   61篇
  2002年   28篇
  2001年   1篇
  2000年   1篇
  1998年   1篇
  1997年   1篇
  1992年   1篇
  1991年   2篇
  1990年   2篇
  1988年   1篇
  1983年   2篇
  1982年   5篇
  1981年   2篇
  1980年   1篇
  1978年   1篇
  1976年   1篇
  1969年   1篇
  1966年   1篇
  1963年   1篇
  1962年   1篇
排序方式: 共有622条查询结果,搜索用时 93 毫秒
91.
Diuretic-resistant congestive heart failure in the form of type 2 cardiorenal syndrome is a problem of growing significance in everyday clinical practice because of high morbidity and mortality. There has been scant progress in the treatment of overhydration, the main cause of symptoms in this group of patients. The aim of our review is to present recent advances in the ultrafiltration therapy of congestive heart failure, with special attention to the new dedicated device for extracorporeal isolated ultrafiltration, as well as modifications of peritoneal dialysis in the form of peritoneal ultrafiltration with icodextrin solution and incremental peritoneal dialysis. Technical and clinical features, costs and potential risks of available devices for isolated ultrafiltration are presented. This method should be reserved for patients with true diuretic resistance as part of a more complex strategy aiming at the adequate control of fluid retention. Peritoneal ultrafiltration is presented as a viable alternative to extracorporeal ultrafiltration because of medical and psychosocial benefits of home-based therapy, lower costs and more effective daily ultrafiltration. In conclusion, large, properly randomized and controlled clinical trials with long-term follow-up will be essential in assessing the logistics and cost-effectiveness of both methods. Most importantly, however, they should be able to evaluate the impact of both methods on preservation of renal function and delaying the progression of heart failure by interrupting the vicious circle of cardiorenal syndrome. Our review is supplemented with the case report of the use of peritoneal ultrafiltration with a single 12-hour nighttime icodextrin exchange as a life-saving procedure in a patient with congestive heart failure resistant to pharmacological treatment.
  相似文献   
92.
In this paper, an antimycobacterial component of extracellular metabolites of a gut bacterium Raoultella ornithinolytica from D. veneta earthworms was isolated and its antimycobacterial action was tested using Mycobacterium smegmatis. After incubation with the complex obtained, formation of pores and furrows in cell walls was observed using microscopic techniques. The cells lost their shape, stuck together and formed clusters. Surface‐enhanced Raman spectroscopy analysis showed that, after incubation, the complex was attached to the cell walls of the Mycobacterium. Analyses of the component performed with Fourier transform infrared spectroscopy demonstrated high similarity to a bacteriocin nisin, but energy dispersive X‐ray spectroscopy analysis revealed differences in the elemental composition of this antimicrobial peptide. The component with antimycobacterial activity was identified using mass spectrometry techniques as a glycolipid–peptide complex. As it exhibits no cytotoxicity on normal human fibroblasts, the glycolipid–peptide complex appears to be a promising compound for investigations of its activity against pathogenic mycobacteria.  相似文献   
93.
This study reports the first case of abducens nerve duplication along its entire intracranial course, ending within the orbit. A distinct abducens nerve duplication reaching the common tendinous ring (annulus of Zinn), as well as another split within the intraconal segment of the nerve have been revealed. Additionally, two groups (superior and inferior) of abducens nerve sub-branches to the lateral rectus muscle were visualised using Sihler’s stain. The analysed anatomical variation has never been reported before and it seems to be in the middle of the spectrum between the cases of duplication occurring only within the intracranial segments of the abducens nerve found in the literature and those continuing throughout the whole course of the nerve. Abducens nerve duplication may be treated as a relic of early stages of ontogenesis. Such a variant might result from alternative developmental pathways in which axons of the abducens nerve, specific for a given segment of the lateral rectus muscle, run separately at some stage, instead of forming a single stem.  相似文献   
94.
The function of 76 patellofemoral knee joints afer replacement with Kinemax condylar prostheses (Howmedica, UK) were evaluated. The indications for arthroplasty were knee destruction caused by rheumatoid arthritis (RA) in 33 cases and osteoarthritis in 35 patients. The average period of observation was 2.5 years. Anterior knee pain was recorded in 15 cases. In 2 cases it was caused by deep infection. In two other knees, the cause of the complaints was subluxation of the prosthetised patellae. In the other 11 cases, pain came from an active rheumatoid process and was less intense than before operation. Disorders of the patellar tracking were recorded in 13 joints even though only 2 were painful. Loosening of the patellar component was not recorded. Evaluation of knee function confirms the need to resurface the patella, especially in patients suffering from RA, and the necessity to be precise in arthroplasty procedure. Received: 11 August 2000; Accepted: 4 October 2000  相似文献   
95.
Background

Peritoneal dialysis (PD) related infections are associated with technique failure and mortality. The aim of this multicentre study was to examine epidemiology, treatment and outcomes of PD-related infections in Poland as well as practice patterns for prevention of these complications in the context of current ISPD recommendations.

Methods

A survey on PD practices in relation to infectious complications was conducted in 11 large Polish PD centres. Epidemiology of peritonitis and exit-site infections (ESI) was examined in all patients treated in these units over a 2 year period.

Results

The study included data on 559 PD patients with 62.4% on CAPD. Practice patterns for prevention of infectious complications are presented. The rate of peritonitis was 0.29 episodes per year at risk, with Gram positive microorganisms responsible for more than 50% of infections and 85.8% effectively treated. Diagnosis and treatment followed ISPD guidelines however most units did not provide an anti-fungal prophylaxis. Although neither of the centres reported routine topical mupirocin on catheter exit-site, the rate of ESI was low (0.1 episodes per year at risk), with Staphylococcus aureus as most common pathogen and full recovery in 78.3% of cases.

Conclusion

The study shows rewarding outcomes in prevention and treatment of PD-associated infections, mainly due to a thorough compliance with the current ISPD guidelines, although some deviations from the recommendations in terms of practice patterns have been observed. More studies are needed in large numbers of patients to differentiate the importance of specific recommendations and further support the guidelines.

  相似文献   
96.
A series of new pentabromobenzylisothioureas [ZKK-1-ZKK-5; (ZKKs)] carrying additional substituents on nitrogen atoms has been synthesized. The ZKKs were found to induce apoptosis in HL-60 (human promyleocytic leukemia) and K-562 (human chronic erythromyeloblastoid leukemia) cell lines in a concentration-dependent manner at low micromolar concentrations. ZKK-3 [(N,N'-dimethyl-S-2,3,4,5,6-pentabromobenzyl)isothiouronium bromide] showed the highest proapoptotic activity in HL-60 cells, whereas ZKK-2 [N-methyl-S-(2,3,4,5,6-pentabromobenzyl)isothiouronium bromide] was most effective in this respect in K-562 cells. During the ZKKs-induced apoptosis, an 85?kDa fragment of cleaved PARP (caspase-3 and caspase-7 substrate) was detected in both cell lines tested. The studied compounds also decreased mitochondrial transmembrane potential in both these cell lines and caused the cells to accumulate in G(1) and at the G(1)/S border of the cell cycle in a concentration-dependent manner. These results show promise for their study as new compounds in the treatment of leukemia, after an appropriate preclinical toxicity profile.  相似文献   
97.

Introduction

Single nucleotide polymorphism in the 3’ untranslated region of the vesicle-associated membrane protein gene (VAMP-8) has been associated with increased risk of early-onset myocardial infarction (MI). In this study the risk of early onset MI conferred by VAMP-8 gene polymorphism was investigated in a group of 171 male subjects.

Material and methods

Male patients with a history of MI who underwent coronary angiography were enrolled and divided into early (incident < 55 years of age) and late (incident ≥ 55 years of age) MI onset groups. Apart from the RFLP-PCR based analysis of the VAMP-8 variant, history of hypertension, lipid abnormalities, smoking and body mass index were recorded. In statistical analyses odds ratios and relative risk were used as a measure of genotype-MI association while logistic regression was implemented for evaluation of MI risk factor strength.

Results

VAMP-8 A allele frequency proved to be significantly higher in the early-onset MI group and conferred higher relative risk of early MI in the investigated cohort, when calculated for the individual A allele (p = 0.029). In logistic regression analyses no association between risk genotypes and traditional risk factors was observed.

Conclusions

In this study VAMP-8 A variant was identified as a risk allele for early MI in male subjects.  相似文献   
98.
99.
Coronary artery fistulas are infrequent congenital malformations. We present the case of a patient with acute coronary syndrome and fistula between the proximal left anterior descending artery (LAD) and the pulmonary artery. The fistula was diagnosed during coronary angiography. Its presence and morphology was confirmed by a 64-slice computer tomography scan. The patient underwent a successful coronary artery bypass grafting procedure with surgical closure of the fistula.  相似文献   
100.
In contrast to the occurrence of brain metastases advanced malignant tumours in adult cancer patients, the dissemination of solid tumours to the brains of paediatric cancer patients is very uncommon. We present a neuro-pathological and clinical study of a group of children and adolescents with brain metastases (BM) from extracranial solid malignancies. The analysed patients were diagnosed with soft tissue sarcomas (three), germ cell tumours (three), or osteosarcoma, neuroblastoma, clear cell sarcoma of the kidney, or pleuropulmonary blastoma (one each). In our series, BM frequently coexisted with pulmonary metastases. Three different metastatic patterns were discernible: a solitary tumour, multiple lesions and diffuse parenchymal dissemination. Two cases showed haemorrhagic presentation. Most of the children died due to BM progression, while children with germ cell tumours showed the best prognosis. The histopathological pictures of BM can be different from the primary tumour, showing dedifferentiation or a diverse neoplastic component. The autopsy examination can still be helpful in the final diagnosis of certain cases with atypical clinical presentations.  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