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51.
Protein-energy malnutrition (PEM) is a serious disease responsible for the high morbidity and mortality rates among children in developing countries. The damaging effects of PEM on their immune system may persist for long throughout their lives. In this study, the levels of the proinflammatory cytokines; Granulocyte-Macrophage colony stimulating factor (GM-CSF), interleukin-8 (IL-8) and interleukin-6 (IL-6) were measured in culture supernates of peripheral blood mononuclear cells (PBMCs) isolated from 46 PEM children before and after stimulation with lipopolysaccharide (LPS). The PEM children were classified into four groups; under weight (u.wt= 15), marasmus (M= 11), marasmic kwashiorkor (MK=10), and kwashiorkor (K=10). Results were compared with those of a control group composed of ten healthy well-nourished age-matching children (C=10). Before LPS stimulation, GM-CSF levels of M, MK and K groups were lower than those of the control group, while IL-8 and IL-6 levels were higher in all PEM groups than in the controls. After LPS stimulation, GM-CSF, IL-8 and IL-6 levels were lower in all PEM groups than controls. The three cytokines' levels were elevated in control and PEM groups after LPS stimulation than before. Before and after LPS stimulation, the highest level of the GM-CSF, IL-8 and IL-6 within PEM children were detected in the u.wt group followed by M, MK and K groups respectively. The disturbance in the production of GM-CSF, IL-8 and IL-6 by PBMCs of PEM children under study and the decreased stimulatory responses of these cells denoted to severely impaired inflammatory response associated with PEM status in addition to several immunological processes in which these cytokines are involved.  相似文献   
52.

Aims:

The aim of the study was to report the incidence of retinopathy of prematurity (ROP) and severe ROP and identify the risk factors for their development in a large nursery in Kuwait.

Materials and Methods:

This was a retrospective, interventional, non-comparative, hospital-based study. Retrospective review of ROP records of premature babies having either birth weight of less than 1501 g or gestational age at birth of 34 weeks or less and born between January 2001 and August 2003.

Statistical Analysis:

By univariate and multivariate logistic regression analysis.

Results:

Out of the 599 babies studied, 38.9% developed ROP and 7.8% needed treatment for severe ROP. Multivariate analysis showed low birth weight (OR 13.753, 95% CI 3.66-51.54; (P < 0.001), gestational age (OR 13.75, 95% CI 3.66-51.54; P < 0.001), surfactant (OR 1.72, 95% CI 1.04-2.83; P = 0.032) and stay in the intensive care unit for longer than 15 days (OR 2.25, 95% CI 1.05-4.85; P = 0.033) to be significant for the development of any ROP. Low birth weight (OR 22.86, 95% CI 3.86-134.82; P = 0.001), bacterial sepsis (OR 3.27, 95% CI 1.51-7.05; P = 0.002) and need for surfactant (OR 4.41, 95% CI 0.94 -20.56; P = 0.059) were found to be the risk factors for severe ROP needing laser treatment.

Conclusion:

The incidence of both any ROP and ROP needing treatment are comparable to other studies. Low birth weight is the most important risk factor for both any ROP and severe ROP.  相似文献   
53.
Human Papillomavirus (HPV) infection is one of the most common sexually transmitted infections and oncogenic HPV is the main cause of cervical cancer. However, HPV vaccination is already available as the primary preventive method against cervical cancer. The objective of this study was to determine the level of knowledge, attitude and practice of HPV vaccination among Universiti Kebangsaan Malaysia (UKM) and Universiti Malaya (UM) students. This study was conducted from March until August 2009. Pre-tested and validated questionnaires were filled by the third year UKM (n=156) and UM (n=149) students from medical, dentistry and pharmacy faculties. The results showed that the overall level of knowledge on HPV infection, cervical cancer and its prevention among respondents was high and the majority of them had positive attitude towards HPV vaccination. Medical students had the highest level of knowledge (p<0.05). Very few students (3.6%) had already taken the vaccine with no significant difference between the two Universities (p=0.399). In conclusion, the knowledge and attitude of the respondents were high and positive, respectively. Only few students took HPV vaccination. Thus, more awareness campaigns and HPV vaccination services should be provided at universities' campuses with the price of the HPV vaccine reduced for the students.  相似文献   
54.
PURPOSE: The purpose of this paper is to show that, although there has been some research to identify the dimensions on which healthcare quality and in-patient satisfaction should be measured, the confirmation of constructs and indicators that constitute an overall care quality and satisfaction remains unclear. The objective is to present several models of service quality and satisfaction in healthcare for discharged patients; and to test those models in a sample of discharged patients in public hospitals in the United Arab Emirates. DESIGN/METHODOLOGY/APPROACH: A detailed in-patient survey (using interviews) was used. Data were collected with questionnaires from adult discharges (n = 244) in public hospitals in the UAE. Several structures are proposed and tested. Confirmatory Factor Analysis (CFA) and LISREL SIMPLIS using maximum likelihood estimation were used to estimate and test the parameters of the hypothesized models derived deductively from the previous literature. FINDINGS: Several models (with one, two, three and four constructs) with different structures were tested using CFA. The final recommended model is based on three constructs--quality of care, process and administration, and information. The goodness-of-fit statistics supported the basic solution of the healthcare quality-satisfaction model. ORIGINALITY/VALUE: The model has been found to capture attributes that characterize healthcare quality in a developing country such as the UAE and could represent other modern healthcare systems. It can be used as a basis for evaluation in healthcare practices from discharges (in-patients) point of view. The study highlights the importance of patients' satisfaction with care as predictors of quality of care. The results also confirm the construct validity of the previously discussed healthcare quality scales.  相似文献   
55.
The development of medical implants is an ongoing process pursued by many studies in the biomedical field. The focus is on enhancing the structure of the implants to improve their biomechanical properties, thus reducing the imperfections for the patient and increasing the lifespan of the prosthesis. The purpose of this study was to investigate the effects of different lattice structures under laboratory conditions and in a numerical manner to choose the best unit cell design, able to generate a structure as close to that of human bone as possible. Four types of unit cell were designed using the ANSYS software and investigated through comparison between the results of laboratory compression tests and those of the finite element simulation. Three samples of each unit cell type were 3D printed, using direct metal laser sintering technology, and tested according to the ISO standards. Ti6Al4V was selected as the material for the samples. Stress–strain characteristics were determined, and the effective Young’s modulus was calculated. Detailed comparative analysis was conducted between the laboratory and the numerical results. The average Young’s modulus values were 11 GPa, 9 GPa, and 8 GPa for the Octahedral lattice type, both the 3D lattice infill type and the double-pyramid lattice and face diagonals type, and the double-pyramid lattice with cross type, respectively. The deviation between the lab results and the simulated ones was up to 10%. Our results show how each type of unit cell structure is suitable for each specific type of human bone.  相似文献   
56.
BackgroundBoth psoas compartment block and fascia iliaca compartment block have been shown to be reliable blocks for postoperative pain relief for procedures involving the hip joint. This study evaluated the efficacy of continuous psoas compartment block with continuous fascia iliaca block for postoperative analgesia after hip surgery.MethodsIn randomized blinded study Forty, ASA I–III patients aged 30–75 years, with BMI less than 40, scheduled for hip surgery, were divided to one of two groups. Group P: continuous psoas compartment block (n = 18) and group F: continuous fascia iliaca block (n = 19). Standard general anesthesia was induced after finishing the block technique. After recovery 30 ml of 0.125% levobupivacaine was injected through the catheter to all patients. Postoperative 24 h meperidine consumption, patient satisfaction, visual analogue scale pain scores at (1, 6, 12, 18, and 24 h) postoperative, postoperative hemodynamics (HR and MAp), evidence of sensory and motor blockades, and incidence of adverse effects were recorded.ResultsThere was no significant difference between the two groups in 24 h postoperative meperidine requirements, postoperative VAS, patient satisfaction, postoperative hemodynamics, and distribution of sensory and motor block of (femoral, lateral femoral cutaneous, and obturator nerves). The epidural anesthesia occurred in two patients in psoas group (11%).ConclusionBoth continuous fascia iliaca block and continuous psoas compartment block were comparable in providing safe and effective analgesia after hip surgery.  相似文献   
57.
We sought to determine whether TDZD-8, the inhibitor of the glycogen synthase kinase-3β (GSK3β), can protect the synovial membrane of the knee joint against injuries induced by collagen type II immunization (CIA) possibly via the downregulation of synovial leukocyte infiltration, endoplasmic reticulum stress (ERS), and autophagy. The model group of rats (CIA) were immunized over a period of 3 weeks with collagen type II, whereas the treated group of rats (CIA + TDZD-8) were treated with TDZD-8 (1 mg/kg) for 21 days after the completion of the immunization regimen. All rats were then killed at week 6. Harvested synovial tissues were prepared for immunohistochemistry staining, and synovial homogenates were assayed for biomarkers of ERS, autophagy, apoptosis, and cell survival and proliferation. In addition, blood samples were assayed for biomarkers of arthritis. Synovial tissue images showed that CIA enhanced leukocyte recruitment as demonstrated by an increased CD45+ (leukocyte common antigen) immunostaining, which was markedly decreased by TDZD-8. TDZD-8 also significantly (P < .05) inhibited collagen-induced autophagy biomarkers Beclin-1 and LC3II, the ERS biomarkers GRP-78, IRE1-α, XBPIs, and eIF2a, and the survival protein Bcl-2. Whereas, the collagen-induced proliferative biomarkers Akt and mTOR were not inhibited by TDZD-8, and CIA inhibited the apoptotic proteins CHOP and cleaved caspase-3, which were augmented by TDZD-8. We further demonstrated a significant (P < .05) correlation between autoantibodies generated during the course of arthritis and biomarkers of ERS and autophagy. We conclude that TDZD-8 inhibits CIA and decreases synovial leukocyte infiltration, ERS, and autophagy, which is independent of Akt/mTOR signalling.  相似文献   
58.
Inorganic metallic halide perovskites and cesium lead triiodide, CsPbI3, in particular, have gained enormous attention recently due to their unique photovoltaic properties and low processing temperatures. However, their structural stability and phase transition still need an in-depth investigation to better optimize their optoelectronic properties. For sake of time and cost, Classical Molecular Dynamics (CMD) and first principles calculations are being used to predict the structure stability and phase transition of CsPbI3. The major challenge of CMD is the choice of proper interatomic potential functions. In this paper, a new hybrid force field is being introduced, which integrates the embedded atomic potentials of Cs–Cs and Pb–Pb with Buckingham–Coulomb potentials. The Buckingham–Coulomb interatomic potential was solely employed as well. The outputs from both force fields were reported and compared to the experimental values. In fact, the new Hybrid Embedded Atomic Buckingham–Coulomb (EABC) potential reproduces, with a great degree of accuracy (within 2.5%), the structural properties, such as the radial distribution functions, interatomic separation distances, and the density. Also, it detects the phase transformation from an orthorhombic into a cubic crystal structure and the melting temperature at 594 K and 750 K respectively which agrees with the experimental values to within 1%. The new proposed hybrid potential proved to be accurate so it could potentially be used to infer the structure stability and the mechanical and thermal properties of the pure inorganic halide perovskites and the mixed halide perovskites as well which are used in various applications.

The new hybrid potential of CsPbI3 accurately reproduces the density, structure and phase transformation from orthorhombic to cubic crystal structure.  相似文献   
59.
60.
To simplify transmitral volume flow determination by Doppler echocardiography, a formula for calculating mean mitral valve orifice area using M-mode echocardiography without any 2-dimensional measurements was developed and evaluated in this study. The maximal mitral orifice area was assumed to be circular and its diameter was calculated from the maximal M-mode mitral leaflet separation. The maximal area was multiplied by the mean to maximal anterior mitral leaflet excursion ratio to correct for phasic changes in flow orifice area during ventricular filling. This measurement had a high correlation (r = 0.97, standard error of the estimate + 0.26 cm2) with mean mitral valve orifice area calculated from frame-by-frame analysis of short-axis 2-dimensional echoes in a select group of 10 normal volunteers and 10 patients with cardiomyopathy who had very high quality images of the mitral valve leaflet tips. Cardiac output calculated using the new method for orifice area estimation combined with apex view mitral valve Doppler velocities was then validated in 48 consecutive patients undergoing thermodilution cardiac output determinations with a close correlation between Doppler and thermodilution cardiac output (2.3 to 6.1 liter/min, r = 0.93, standard error of the estimate = 362 ml). The correlation improved when 12 patients with mild mitral insufficiency were excluded (r = 0.95). The M-mode echocardiogram-derived mitral valve orifice method combined with Doppler mitral valve velocities is accurate, easy to perform, has a high success rate and should increase the applicability of Doppler echocardiography for estimation of cardiac output.  相似文献   
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