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101.

INTRODUCTION

The present study aimed to determine the impact of an extended infection control training programme, which was conducted for all interns posted to the Department of Paediatrics, on the incidence of paediatric intensive care unit (PICU)-acquired bloodstream infections (BSIs) in University Malaya Medical Centre, Malaysia.

METHODS

The development of nosocomial BSIs during the baseline period (1 January–31 October 2008) and intervention period (1 November–31 December 2009) was monitored. During the intervention period, all paediatric interns underwent training in hand hygiene and aseptic techniques for accessing vascular catheters.

RESULTS

A total of 25 patients had PICU-acquired BSIs during the baseline period, while 18 patients had PICU-acquired BSIs during the intervention period (i.e. infection rate of 88 per 1,000 and 41 per 1,000 admissions, respectively). The infections were related to central venous catheters (CVCs) in 22 of the 25 patients who had PICU-acquired BSIs during the baseline period and 11 of the 18 patients who had PICU-acquired BSIs during the intervention period. Thus, the incidence rates of catheter-related BSIs were 25.2 per 1,000 CVC-days and 9.3 per 1,000 CVC-days, respectively (p < 0.05). The Paediatric Risk of Standardised Mortality III score was an independent risk factor for PICU-acquired BSIs and the intervention significantly reduced this risk.

CONCLUSION

The education of medical interns on infection control, a relatively low-cost intervention, resulted in a substantial reduction in the incidence of PICU-acquired BSIs.  相似文献   
102.
103.
104.
This research work focuses on the synthesis and performance evaluation of NaFexCr1−X(SO4)2 (X = 0, 0.8 and 1.0) cathode materials in sodium ion batteries (SIBs). The novel materials having a primary particle size of around 100–200 nm were synthesized through a sol–gel process by reacting stoichiometric amounts of the precursor materials. The structural analysis confirms the formation of crystalline, phase pure materials that adopt a monoclinic crystal structure. Thermal analysis indicates the superior thermal stability of NaFe0.8Cr0.2(SO4)2 when compared to NaFe(SO4)2 and NaCr(SO4)2. Galvanostatic charge/discharge analysis indicates that the intercalation/de-intercalation of a sodium ion (Na+) into/from NaFe(SO4)2 ensues at about 3.2 V due to the Fe2+/Fe3+ active redox couple. Moreover, ex situ XRD analysis confirms that the insertion/de-insertion of sodium into/from the host structure during charging/discharging is accompanied by a reversible single-phase reaction rather than a biphasic reaction. A similar sodium intercalation/de-intercalation mechanism has been noticed in NaFe0.8Cr0.2(SO4)2which has not been reported earlier. The galvanostatic measurements and X-ray photoelectron spectroscopy (XPS) analysis confirm that the Cr2+/Cr3+ redox couple is inactive in NaFexCr1−X(SO4)2 (X = 0, 0.8) and thus does not contribute to capacity augmentation. However, suitable carbon coating may lead to activation of the Cr2+/Cr3+ redox couple in these inactive materials.

This research work focuses on the synthesis and performance evaluation of NaFexCr1−X(SO4)2 (X = 0, 0.8 and 1.0) cathode materials in sodium ion batteries (SIBs).  相似文献   
105.

Background

Gadolinium (Gd) Extracellular volume fraction (ECV) by Cardiovascular Magnetic Resonance (CMR) has been proposed as a non-invasive method for assessment of diffuse myocardial fibrosis. Yet only few studies used 3 T CMR to measure ECV, and the accuracy of ECV measurements at 3 T has not been established. Therefore the aims of the present study were to validate measurement of ECV by MOLLI T1 mapping by 3 T CMR against fibrosis measured by histopathology. We also evaluated the recently proposed hypothesis that native-T1 mapping without contrast injection would be sufficient to detect fibrosis.

Methods

31 patients (age = 58 ± 17 years, 77 % men) with either severe aortic stenosis (n = 12) severe aortic regurgitation (n = 9) or severe mitral regurgitation (n = 10), all free of coronary artery disease, underwent 3 T-CMR with late gadolinium enhancement (LGE) and pre- and post-contrast MOLLI T1 mapping and ECV computation, prior to valve surgery. LV biopsies were performed at the time of surgery, a median 13 [1–30] days later, and stained with picrosirius red. Pre-, and post-contrast T1 values, ECV, and amount of LGE were compared against magnitude of fibrosis by histopathology by Pearson correlation coefficients.

Results

The average amount of interstitial fibrosis by picrosirius red staining in biopsy samples was 6.1 ± 4.3 %. ECV computed from pre-post contrast MOLLI T1 time changes was 28.9 ± 5.5 %, and correlated (r = 0.78, p < 0.001) strongly with the magnitude of histological fibrosis. By opposition, neither amount of LGE (r = 0.17, p = 0.36) nor native pre-contrast myocardial T1 time (r = −0.18, p = 0.32) correlated with fibrosis by histopathology.

Conclusions

ECV determined by 3 T CMR T1 MOLLI images closely correlates with histologically determined diffuse interstitial fibrosis, providing a non-invasive estimation for quantification of interstitial fibrosis in patients with valve diseases. By opposition, neither non-contrast T1 times nor the amount of LGE were indicative of the magnitude of diffuse interstitial fibrosis measured by histopathology.  相似文献   
106.
Background

Pakistan has a high maternal mortality ratio and a low rate of skilled birth attendants (SBAs). To address these two important issues, the Pakistan Maternal Newborn and Child Health (MNCH) programme launched the community midwives (CMW) initiative in 2007. CMWs are supposed to conduct deliveries at community level outside health facilities. The purpose of the current study is to document perceptions about CMWs and preferences for birthing place.

Methods

A mixed-methods study was conducted covering four provinces. For the quantitative survey, households were selected through a multistage sampling technique from rural districts. In 1,450 rural households, preferences of respondents about CMW-conducted deliveries were recorded. Qualitative data were obtained through focus group discussions (FGDs) and in-depth interviews (IDIs) with women, community elders, CMWs, and MNCH programme personnel in the same areas where the quantitative study was carried out. In both studies, preferences and the reasons behind particular respondent preferences were recorded. Frequencies of responses were analysed for the quantitative study. Narration and quotes from various types of participants were used to present findings from FGDs and IDIs.

Results

In the quantitative study, 42% of respondents expressed a preference for birthing stations, i.e. a place where CMWs conduct deliveries; 22% preferred home deliveries. Birthing stations were favoured because of the availability of space and equipment and the proximity to women’s homes. These findings were largely supported by the qualitative component, although a range of views about where a CMW should conduct deliveries were expressed.

Conclusion

Insights into where CMWs might provide delivery services were obtained through this study. Birthing stations may be an option as a preferred location for delivery care and should be considered as part of Pakistan’s national CMW programme.

  相似文献   
107.
This research study was conducted to evaluate the efficacy of chronic cyanidin‐3‐glucoside (C3G) on alleviation of learning and memory deficits in diabetic rats as a result of the observed antidiabetic and antioxidant activity of C3G. Male Wistar rats were divided into control, diabetic, C3G‐treated‐control and ‐diabetic groups. The C3G was administered i.p. at a dose of 10 mg/kg on alternate days for eight weeks. For evaluation of learning and memory, initial latency (IL) and step‐through latency (STL) were determined at the end of study using passive avoidance test. Meanwhile, spatial recognition memory was assessed as alternation in the Y‐maze task. Oxidative stress markers in brain tissue were also measured. It was found that the alternation score of the diabetic rats was lower than that of control (p < 0.01) and C3G‐treated diabetic rats showed a higher alternation score as compared to diabetic group (p < 0.05). Diabetic rats also developed a significant impairment in retention and recall in passive avoidance test (p < 0.01) and C3G treatment of diabetic rats did not produce any significant improvement. Meanwhile, increased level of malondialdehyde (MDA) in diabetic rats was significantly reduced following C3G treatment (p < 0.05). Taken together, chronic C3G could improve short‐term spatial recognition memory disturbance in the Y‐maze test but not retention and recall capability in passive avoidance test in STZ‐diabetic rats. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
108.
Pleiotropic anti-restenotic properties of drugs that are eluted from coated stents are critical for efficacy and safety. Little is known about comparative drug properties in appropriate human coronary target cell lines for the two compounds that are utilized on FDA-approved drug-eluting stent (DES) platforms, paclitaxel (PTX) and sirolimus (SRL). Target cell lines that play a pivotal role for the pathogenesis of restenosis and vascular healing include human coronary artery smooth muscle (CASMC) and endothelial cells (CAEC). PTX and SRL inhibited CASMC and CAEC proliferation and migration efficiently. However, there was a differential effect on proliferation and migration in CAEC with a more profound inhibition of both parameters by PTX, even at low dosages. Induction of cytotoxicity and apoptosis was pronounced in PTX- and very modest in SRL-treated CASMC and CAEC. PTX increased eNOS activity and nitric oxide (NO) release from CAEC. Neutrophilic leukocyte activation and transmigration, which should be avoided since it may precipitate adverse coronary events such as restenosis and stent thrombosis, was suppressed by SRL, whereas PTX tended to increase neutrophilic leucocyte activity. Therefore, although the primary drug target, inhibition of mitogen-mediated CASMC proliferation, is effectively accomplished by both drugs, auxiliary pharmacological properties that are crucial for the anti-restenotic drug effect and vascular healing are considerably different between PTX and SRL. In comparison with PTX, SRL shows minor interference with endothelial cell proliferation and migration, lower levels of cytotoxicity and apoptosis, a broader therapeutic range and distinctive immunosuppressive properties.  相似文献   
109.
OBJECTIVE: There is a well-documented association between obesity and heart failure although the mechanistic basis for this correlation is unclear. Both extracellular matrix remodeling and left ventricular hypertrophy are well-defined components of remodeling in heart failure, and here we further investigate the role of leptin, the obese gene product, on these parameters. METHODS: We used primary human pediatric ventricular cardiomyocytes combined with gelatin zymography, quantitative PCR analysis, proline and leucine incorporation assays, and investigation of kinase activation by Western blotting. RESULTS: We show using gelatin zymography that leptin dose-dependently (0-60 nM) increased proteolytic activity at approximately 72 kDa. Accordingly, upon quantitative PCR analysis we found that leptin increased expression of matrix metalloproteinase-2 (MMP-2). Leptin also caused an increase in collagen type III and IV mRNA expression and a decrease in collagen type I mRNA expression. This was reflected in no significant change in total collagen synthesis, measured by [3H]proline incorporation, in response to leptin. A statistically significant increase in cell size, [3H]leucine incorporation, and expression of well-characterized markers of cardiac hypertrophy, namely cardiac alpha-actin and myosin light chain, were observed in response to leptin. We demonstrate activation of Janus-activated kinase and mitogen-activated protein kinase pathways by leptin, and using pharmacological inhibitors we show that these signaling pathways play a role in mediating the effects of leptin. CONCLUSIONS: Our findings show that leptin regulates cell size, stimulates MMP-2 expression, and alters the profile, but not the total content, of collagen in human cardiomyocytes. This indicates the potential for altered leptin sensitivity to directly regulate cardiac remodeling in obesity.  相似文献   
110.
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