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Opiate abuse has been a matter of serious concern in male adolescents. This study investigates the effects of chronic morphine administration on serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone levels, testicular histology, and body and testes weight in developing male rats. Animals were subcutaneously injected with morphine (5 mg/kg) or saline (1 mL/kg) twice daily for 30 days. Body weight determinations and injections were carried out under light ether anesthesia. At the end of the experiments, the rats were decapitated and blood samples were collected. Serum levels of LH and FSH were measured. Chronic morphine administration significantly decreased decreased serum testosterone (p < .02) and LH (p < .01) levels, but not FSH release compared to controls. Morphine exposure reduced body weight (p < .01), but had no significant effect on the testicular weight. When the testicular tissue was histologically examined, structural features of the seminiferous tubules and Leydig cells were similar in both saline and morphine-treated animals. The results suggest that opiates affect testosterone release through the hypothalamo-hypophyseal-gonadal axis rather than by a local testicular mechanism. Chronic morphine exposure during sexual maturation may have long-term endocrine disturbances in male rats.  相似文献   
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Background

To examine the psychotropic medication utilization and compare adherence to treatment regimens in pediatric bipolar depression patients.

Methods

2003–2007 MAX data from four geographically diverse states were used. According to the regimen received by the patients (6–18 years) in the first month after the index bipolar depression diagnosis, patients were categorized into six mutually exclusive groups. The month to month change of treatment regimen in each group was then assessed during the 6 month post-index bipolar depression diagnosis. Adherence to each regimen was measured as continuation of the initial regimen, switch to a new regimen, augmentation with medication from a different therapeutic category, and discontinuation of all pharmacotherapies. Repeated measure analysis was conducted to compare the trend of each adherence measure across the study groups.

Results

Of the 5,460 subjects identified, 15.39% received antipsychotic monotherapy, 9.43% received mood stabilizer monotherapy, 5.77% received antidepressant monotherapy, 26.48% received mood stabilizer–antipsychotic polytherapy, 22.51% received antidepressant polytherapy, and 19.89% received antipsychotic–mood stabilizer–antidepressant polytherapy. At the end of the follow-up period, over 50% of the 1st month polytherapy users and less than 50% of the monotherapy users were continuing their initial regimen. Repeated measure analysis using antipsychotic monotherapy as the reference group suggested differences in trend slopes (p<0.05).

Limitations

In absence of structured clinical evaluation, bipolar disorder diagnoses cannot be ascertained in this study.

Conclusions

Bipolar depression patients were predominantly treated with combinations of psychotropic drugs. Potentially questionable practice, such as antidepressant monotherapy was used only in a small fraction of patients. Combination regimens had better adherence as compared to monotherapies.  相似文献   
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Sucrose-free milk chocolates containing different types of bulk (isomalt, xylitol and maltitol) and high intensity (Stevia) sweeteners were produced by using a ball mill. The main quality characteristics of the formulated chocolates were evaluated and compared with those of the conventional sample containing sucrose. The Casson model was the best fitting model for the rheological data. Casson viscosity and Casson yield stress were significantly affected by the type of bulking agent in chocolates formulated with xylitol (p < 0.05). However xylitol notably improved the overall acceptability according to the sensory analysis results. Chocolates containing the sucrose replacers demonstrated lower Tonset values and higher enthalpy than the control sample. Sucrose-free chocolates illustrated a higher degree of particle agglomeration. Bulk sweeteners meanwhile seem to have high potential for milk chocolate production with low calorie values by using the ball mill technique. Industrial applications: the production of sucrose-free chocolates with conventional methods requires a lot of time and energy. Recently, using alternative methods for chocolate production has been raising interest in many small industries. This study proposed a ball mill method for the preparation of sucrose-free milk chocolates with physiochemical properties almost ranging in the standard limit defined for chocolate. Although using the ball mill method presents a more cost-effective technique for chocolate production and provides shorter processing times for small chocolate industries, it seems to be less efficient in evaporating moisture than the conventional processing. Challenges are still ahead for upgrading this alternative technique to be efficient in evaporating more moisture during operation ending in a high quality product.

Sucrose-free milk chocolates containing different types of bulk (isomalt, xylitol and maltitol) and high intensity (Stevia) sweeteners were produced by using a ball mill.  相似文献   
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Cartilage is avascular with limited to no regenerative capacity, so its loss could be a challenge for reconstructive surgery. Current treatment options for damaged cartilage are also limited. In this aspect there is a tremendous need to develop an ideal cartilage-mimicking biomaterial that could repair maxillofacial defects. Considering this fact in this study we have prepared twelve silicone-based materials (using Silicone 40, 60, and 80) reinforced with hydroxyapatite, tri-calcium phosphate, and titanium dioxide which itself has proven their efficacy in several studies and able to complement the shortcomings of using silicones. Among the mechanical properties (Young’s modulus, tensile strength, percent elongation, and hardness), hardness of Silicone-40 showed similarities with goat ear (P > .05). Silicone peaks have been detected in FTIR. Both AFM morphology and SEM images of the samples confirmed more roughed surfaces. All the materials were nonhemolytic in hemocompatibility tests, but among the twelve materials S2, S3, S5, and S6 showed the least hemolysis. For all tested bacterial strains, adherence was lower on each material than that grown on the plain industrial silicone material which was used as a positive control. S2, S3, S5, and S6 samples were selected as the best based on mechanical characterizations, surface characterizations, in vitro hemocompatibility tests and bacterial adherence activity. So, outcomes of this present study would be promising when developing ideal cartilage-mimicking biocomposites and their emerging applications to treat maxillofacial defects due to cartilage damage.  相似文献   
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Transcatheter therapy of intravisceral bleeding   总被引:1,自引:0,他引:1  
Intravisceral bleeding is a life-threatening situation demanding fast and active steps to control, unless it stops spontaneously as in a few lucky patients. A surgical approach is a major intervention with its associated procedural risks when the site is in organs other than the spleen. The transcatheter approach helps in precise location and embolization of the bleeding site; it is a more practical approach that has been known for the past 2 decades to be effective and provide good long-term results. However, the transcatheter approach has been reported in fewer than 200 cases in the literature. Our small series of 43 cases shows initial success of 95% and a fatal early recurrence of only 2.4%. Non-hemorrhagic etiology (sepsis, head injury, etc.) was the major cause of early death (14.6%) among the successfully embolized cases. Long-term follow-up shows recurrence (4.8%) only in the group of chronic etiology. Transcatheter embolization of intravisceral bleeding with Gel-Foam and/or poly-vinyl alcohol particles is a swift, effective and precise method of treatment without major operational hazards.  相似文献   
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Chronic alcohol abuse is characterized by impaired cognitive abilities with a more severe deficit in visual than in verbal functions. Neuropathologically, it is associated with widespread brain structural compromise marked by gray matter shrinkage, ventricular enlargement, and white matter degradation. The present study sought to increase current understanding of the impairment of visual processing abilities in alcohol-dependent subjects, and its correlation with white matter microstructural alterations, using diffusion tensor imaging (DTI). To that end, a DTI study was carried out on 35 alcohol-dependent subjects and 30 healthy male control subjects. Neuropsychological tests were assessed for visual processing skills and deficits were reported as raw dysfunction scores (rDyS). Reduced FA (fractional anisotropy) and increased MD (mean diffusivity) were observed bilaterally in inferior and superior fronto-occipital fasciculus (FOF) fiber bundles. A significant inverse correlation in rDyS and FA values was observed in these fiber tracts whereas a positive correlation of these scores was found with the MD values. Our results suggest that FOF fiber bundles linking the frontal lobe to occipital lobe might be related to visual processing skills. This is the first report of an alteration of the white matter microstructure of FOF fiber bundles that might have functional consequences for visual processing in alcohol-dependent subjects who exhibit no neurological complications.  相似文献   
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