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91.

Background

The ministry of health and medical education of Iran and many other countries advice physicians to use this guideline for diagnosis and treatment of acute otitis media (AOM), but there is not any evaluation of effectiveness and obedience of this guideline, so the aim of this study was to evaluate the attitude of pediatricians, the most important group that interfere with these patients in treatment of acute otitis media.

Methods

A total of 120 anonymous surveys were mailed to 120 pediatrician in Tehran (Iran) to evaluate pattern of diagnosis and treatment of AOM in these physicians. Age, gender, place of work, attitude of diagnosis and treatment were asked by anonymous survey.

Results

Sixty-two completed surveys were received, for a response rate of 51%. There was no significant difference between responders in these survey and scenarios, according to sex, age, practice setting, graduation year or the number of AOM patients visiting each month.

Conclusion

Our study seems to add new insights to the previous literature on management of AOM according to guideline. We can assess the impact of guidelines on the usual practice of practitioners in evidenced-based management of AOM.  相似文献   
92.
The R6/2 mouse is the most frequently used model for experimental and preclinical drug trials in Huntington's disease (HD). When the R6/2 mouse was first developed, it carried exon 1 of the huntingtin gene with ~150 cytosine-adenine-guanine (CAG) repeats. The model presented with a rapid and aggressive phenotype that shared many features with the human condition and was particularly similar to juvenile HD. However, instability in the CAG repeat length due to different breeding practices has led to both decreases and increases in average CAG repeat lengths among colonies. Given the inverse relationship in human HD between CAG repeat length and age at onset and to a degree, the direct relationship with severity of disease, we have investigated the effect of altered CAG repeat length. Four lines, carrying ~110, ~160, ~210, and ~310 CAG repeats, were examined using a battery of tests designed to assess the basic R6/2 phenotype. These included electrophysiological properties of striatal medium-sized spiny neurons, motor activity, inclusion formation, and protein expression. The results showed an unpredicted, inverted "U-shaped" relationship between CAG repeat length and phenotype; increasing the CAG repeat length from 110 to 160 exacerbated the R6/2 phenotype, whereas further increases to 210 and 310 CAG repeats greatly ameliorated the phenotype. These findings demonstrate that the expected relationship between CAG repeat length and disease severity observed in humans is lost in the R6/2 mouse model and highlight the importance of CAG repeat-length determination in preclinical drug trials that use this model.  相似文献   
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In the pursuit of novel antibacterial agents with the 2-thiazolylimino-4-thiazolidinone as a core structure, a series of 5-nitro-heteroarylidene and 5-(2-oxoindolin-3-ylidene) analogs of 2-thiazolylimino-5-arylidene-4-thiazolidinone were synthesized and their antibacterial activities were evaluated against some strains of Gram-positive and Gram-negative bacteria, as well as Helicobacter pylori strains. Biological data indicated that 5-nitrofuran analog 5a and 5-nitroimidazole analog 7a containing no substitutions on the thiazole ring were the most potent compounds.  相似文献   
95.
BackgroundPatients with polycystic ovary syndrome (PCOS) have an increased prevalence of thrombophilia, leading to higher rates of pregnancy loss. The aim of this study was to determine the association between thrombophilia and recurrent pregnancy loss (RPL) in patients with and without PCOS.MethodsIn this comparative case–control study, we included 60 patients with RPL (≥3 consecutive pregnancy losses at <20 weeks of gestation) and PCOS (Group 1), 60 patients with PCOS and without RPL (Group 2), 60 patients with RPL and without PCOS (Group 3), and 60 healthy individuals (Group 4). These four study groups were compared regarding serum levels of testosterone, fasting insulin, homocysteine (Hcy), plasminogen activator inhibitor activity (PAI-Fx), protein C, protein S, antithrombin III, activated protein C ratio (APCR), factor V Leiden, prothrombin G20210A, and methylene tetrahydrofolate reductase gene mutations.ResultsPatients in Group 1 had significantly higher levels of testosterone (p = 0.026), dehydroepiandrosterone sulfate (p = 0.035), fasting insulin (p = 0.015), Hcy (p = 0.036), and PAI-Fx (p = 0.008) compared to Group 3. They also had higher proportions of APCR (p = 0.009) and a higher prevalence of factor V Leiden mutations compared to Group 3 (p = 0.001). However, there was no significant difference in protein C (p = 0.088), protein S (p = 0.514), or antithrombin III (p = 0.627) between the four study groups.ConclusionHyperinsulinemia, hyperandrogenemia, hypofibrinolysis, and hyperhomocysteinemia as well as APCR and factor V Leiden mutations are associated with RPL in patients with PCOS.  相似文献   
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97.
Few studies have reported neuropsychiatric symptoms (NPS) in primary progressive aphasia (PPA), a neurodegenerative disorder that primarily affects the left hemisphere. Depression is associated with left-sided stroke, but it remains unclear whether depression and other NPS are also associated with PPA. The authors compared the frequency of neuropsychiatric symptoms in 55 cases of PPA with 110 cognitively normal persons matched for age, sex, and education. Depression, apathy, agitation, anxiety, appetite change, and irritability are associated with PPA. Hallucinations, delusions, and night-time behavior were not associated with PPA.  相似文献   
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Emad A  Emad Y 《Respiratory medicine》2007,101(4):786-792
OBJECTIVE: In an attempt to understand better the potential role of the T cell in the pathogenesis of pulmonary fibrosis (PF) due to sulfur mustard gas inhalation, this study was designed to analyze bronchoalveolar lavage (BAL) lymphocyte subsets and to determine the ratio of CD4 to CD8 lymphocytes in BAL fluid. SETTING: University hospital. PATIENTS: Twenty-one veterans with mustard gas-induced pulmonary fibrosis and 20 normal veterans as control group. INTERVENTION: Chest roentgenograms, pulmonary function tests (PFTs), tests for carbon monoxide diffusing capacity of the lung (DLCO), high-resolution CT scans of the chest, BAL via fiberoptic bronchoscopy, analyses of BAL fluids for cellular and Flow-cytometric analysis of the phenotype of bronchoalveolar cells were performed in all cases. A transbronchial lung biopsy was done in all patients following BAL. RESULTS: Neutrophilic alveolitis was the predominant feature. Neutrophils (P<0.0001) and eosinophils (P=0.0006) were the predominant cell types in the BAL fluid of patients with PF. CD8 lymphocytes expressed as percentage or absolute number were significantly higher in patients with PF than in healthy controls (22.96+/-7.48% vs. 14.16+/-7.73%, respectively; P=0.0006; and 2.28+/-0.84 vs. 1.10+/-0.55 x 10(3) cells/ml, respectively; P<0.0001). The CD4/CD8 ratio was significantly lower in patients with PF than in healthy controls (0.73+/-0.25 vs. 1.58+/-0.67; P<0.0001). Except for the percentage and the absolute number of the BAL fluid neutrophils (r=0.70, P=0.001: r=-0.62, P=0.005; respectively), no correlation was found between DLCO% and the other BAL cells. A significant negative correlation was observed between the percentage of DLCO and both the percentage and the absolute number of CD8 lymphocytes in BAL fluid in patients with PF (r=-0.81, P=0.0003; r=-0.61, P=0.006; respectively). A significant correlation was also seen between the percentage of DLCO and the CD4/CD8 ratio (r=-0.60, P=0.006) in our patients. CONCLUSION: CD8 T cells in BAL fluid were significantly elevated in patients with pulmonary fibrosis. Patients with higher grades of pulmonary fibrosis expressed as percentage of DLCO, revealed higher percentages and the absolute number of CD8 T cells and a lower CD4/CD8 ratio.  相似文献   
100.
Profound bone loss at weight bearing sites is a primary effect of long-duration spaceflight. Moreover, a significant increase in estimated fracture risk remains even 1 year after returning to Earth; hence, it is important to define how quickly bone integrity can recover following prolonged disuse. This study characterized the loss and recovery dynamics of bone following a period of rodent hindlimb unloading in three anatomic sites. We hypothesized that the rat femoral neck would exhibit a discordant recovery dynamic most similar to that observed in astronauts' proximal femur; that is, bone mineral content (absolute mass) at this site would recover faster and more completely than would bone density and cortical area, and they will all recover before bone strength does. We characterized loss and long-term recovery of densitometric properties at the femoral neck, proximal tibia metaphysis, and tibia diaphysis, and also mechanical properties at the femoral neck and tibia diaphysis for which mechanical testing is amenable. We assessed the relationship between calculated strength indices and measured mechanical properties.Adult male Sprague–Dawley rats (6 months) were assigned to baseline, age-matched control (AC), and hindlimb unloaded (HU) groups. The HU group was unloaded for 28 days and then returned to normal cage activity for 84 days of weight bearing recovery (3 times the duration of HU). Fifteen animals were euthanized from each of the HU and AC groups on days 28, 56, 84, and 112 of the study. At baseline and then every 28 days in vivo longitudinal pQCT scans were taken at proximal tibia metaphysis (PTM) and tibia diaphysis (TD); ex vivo pQCT scans were taken later at the femoral neck (FN). TD and FN were tested to failure to measure mechanical properties.The hypothesis that the femoral neck in rats will exhibit a discordant recovery dynamic most similar to that observed in astronauts' proximal femurs was not supported by our data. At the femoral neck, densitometric and geometric variables (total BMC, total vBMD, cancellous vBMD, and cortical area) recovered to age-matched control levels after a recovery period twice the duration of unloading. Contrary to our hypothesis, changes in densitometric variables at the PTM provided a better model for changes in the human femoral neck with prolonged weightlessness. Following 28 days of HU, PTM total BMC recovered to age-matched control levels after roughly two times the duration of unloading; however, total vBMD did not recover even after three recovery periods. Cortical thinning occurred at the PTM following HU likely due to inhibition of periosteal growth; cortical shell thickness did not recover even after three recovery periods. Calculated strength indices suggested a loss in strength at the tibial diaphysis, which was not confirmed with direct testing of mechanical properties. HU had no effect on maximum fracture force at mid-tibia diaphysis; however, femoral neck experienced a significant loss of maximum force due to unloading that fully recovered after 28 days. Estimated strength indices for the femoral neck suggested a recovery period of 56 days in contrast to the 28-day recovery that was observed with mechanical testing. However, the inaccuracy of strength indices vs. directly measured mechanical properties highlights the continued importance of ground based animal models and mechanical testing. Our results demonstrate that the PTM in the rat better matches loss and recovery dynamics observed in astronauts' proximal femur than does the rat FN, at least in terms of densitometric variables. More complete utility of the rat PTM as a model in this case, however, depends upon meaningful characterization of changes in mechanical properties as well.  相似文献   
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