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101.
Potential of wastewater treatment in car industry and groundwater contamination by volatile organic compounds include perchloroethylene (PCE), trichloroethylene (TCE) and dichloromethane (DCM) near car industry was conducted in this study. Samples were collected in September through December 2011 from automobile industry. Head-space Gas chromatography with FID detector is used for analysis. Mean PCE levels in groundwater ranged from 0 to 63.56 μg L?1 with maximum level of 89.1 μg L?1. Mean TCE from 0 to 76.63 μg L?1 with maximum level of 112 μg L?1. Due to the data obtained from pre treatment of car staining site and conventional wastewater treatment in car factory, the most of TCE, PCE and DCM removed by pre aeration. Therefor this materials entry from liquid phase to air phase and by precipitation leak out to the groundwater. As a consequence these pollutants have a many negative health effect on the workers by air and groundwater.  相似文献   
102.
The aim of this study was to investigate the magnitude of mandibular incisor retraction to be expected during full fixed appliance mechanotherapy in Class II Division 1 malocclusions treated with premolar extractions when mandibular incisor retraction was not part of the treatment plan. The material consisted of pretreatment and posttreatment cephalometric films and dental casts of 70 Class II Division 1 malocclusion patients (33 males and 37 females) treated with the preadjusted edgewise appliances. The mandibular first premolars were extracted in 31 subjects, and the mandibular second premolars were extracted in 39. The pretreatment factors that suggested a basis for the extraction choice in the mandibular arch in these patients were found to include the ratio between posterior and anterior facial heights, the maxillary-mandibular plane angle, and the residual space in the mandibular arch. The mandibular incisors were retracted in only 65% of the patients. On average, the mandibular incisors were retracted by 1.02 mm relative to the nasion-pogonion line; there was no significant difference between the 2 extraction groups. Multiple regression analysis showed that the change in the mandibular incisor position is significantly correlated with the residual space in the mandibular arch, the initial distance between the mandibular incisor and the nasion-pogonion line, maxillary-mandibular angle, and the duration of crown labial torque in the mandibular incisors. In combination, these 4 factors could explain 61% of the change in the mandibular incisor position.  相似文献   
103.
The purpose of this study was to investigate the effects of oral administration of misoprostol, a prostaglandin E1 analog, on orthodontic tooth movement and root resorption in rats. Sixty-four male Sprague-Dawley rats that initially weighed 250 +/- 20 g were used in this study. The animals were randomly assigned to 1 of 6 experimental and 2 control (nonappliance and appliance) groups. The experimental groups received 2.5, 5.0, 10.0, 25.0, 50.0, and 100.0 microg/kg misoprostol by gastric lavage every 24 hours for 2 weeks. A fixed orthodontic appliance consisting of a nickel-titanium closed-coil spring, 5.0 mm long was ligated between the maxillary right incisor and the maxillary right first molar. The initial activating force was 60 g. For analysis of root resorption, 99 maxillary right and left first molars from 61 animals were chosen. Serial histologic sections of the mesial root of the maxillary first molars were made, and histologic analysis of root resorption on the mesial and distal surfaces was performed. The results showed that oral misoprostol did increase the amount of orthodontic tooth movement in all the experimental groups compared with the appliance control group. This increase was statistically significant in doses of 10.0, 25.0, 50.0, and 100.0 microg/kg (P <.001). However, there were no statistically significant differences among these 4 different doses. There were no statistically significant differences in the amount of root resorption among the groups. However, a trend toward more root resorption was registered. On the basis of these findings, oral misoprostol can be used to enhance orthodontic tooth movement with minimal root resorption.  相似文献   
104.
105.
PURPOSE: Chronic ischemia has been shown to alter bladder contractility. We studied the roles of cyclooxygenase (COX) and lipoxygenase products in ischemia induced bladder overactivity in the rabbit. MATERIALS AND METHODS: A total of 28 male New Zealand White rabbits were divided into 2 groups. In group 1 atherosclerotic occlusion of the iliac arteries was induced by balloon endothelial injury, followed by a short period of a high cholesterol diet. Group 2 received a regular diet alone. After 12 weeks blood flow measurements and cystometry were performed. Bladder tissues were processed for enzyme immunoassay of leukotrienes and prostaglandins (PGs), Western blotting of COX and lipoxygenase, isometric tension measurement and histology. RESULTS: Atherosclerotic occlusion of the iliac arteries significantly decreased bladder blood flow. Moderate ischemia caused bladder overactivity, while severe ischemia inhibited bladder contractions. Ischemia increased leukotriene B4, E4 and C4 release by 141%, 132% and 254%, and increased PG F2alpha and thromboxane A2 release by 95% and 93%, respectively, although it did not alter PG E2 release. Western blotting showed increased 5-lipoxygenase, COX-1 and COX-2 protein levels in ischemic bladder tissues. Moderate ischemia increased bladder smooth muscle contraction in response to carbachol and electrical field stimulation. Tissue treatment with the COX inhibitor indomethacin significantly increased control tissue contraction but had no effect on ischemic tissues. Treatment with the 5-lipoxygenase inhibitor REV5901 abolished this effect of indomethacin in control tissues. Treatment with REV5901 significantly decreased the contraction of ischemic tissues but had no significant effect on control tissues. The effect of indomethacin plus REV5901 was similar to the effect of REV5901 alone. Histology showed urothelial thickening and mild fibrosis in the moderately ischemic bladder. CONCLUSIONS: Chronic ischemia increased bladder 5-lipoxygenase, and COX-1 and COX-2 protein expression, and altered leukotriene and PG production. Treatment with COX and lipoxygenase inhibitors produced completely different effects in the ischemic bladder compared with the control bladder. Functional changes in the ischemic bladder were concurrent with structural changes in the urothelium. PGs modulate smooth muscle contractility in the healthy bladder. However, under ischemic conditions leukotrienes dominate bladder tone and appear to have a leading role in increased smooth muscle contraction and bladder overactivity.  相似文献   
106.
107.

Ethnopharmacological relevance

According to the Chinese, European, Iranian and Indian traditional medicines, oleo gum resin of Ferula assa-foetida (asafoetida) has therapeutic effects on different kinds of diseases. Some of these effects are related to the diseases of nervous system such as hysteresis and convulsion. In recent studies, some anti-epileptic and neuroprotective roles were also considered for it and we examined its possible role on treatment of peripheral neuropathy.

Material and methods

in vitro studies were carried out to identify the response of isolated sciatic nerves to different concentrations of oleo gum resin of asafoetida solved in Lock?s solution. Then, in vivo studies were conducted to evaluate its effect on amelioration of peripheral neuropathy in mice. Peripheral neuropathy was induced by intraperiotoneal injection of high doses of pyridoxine in adult Balb/c male mice. Tail flick tests were performed to identify the incidence of neuropathy in animals. After 10 days treatment with asafoetida, the efficiency of treatment was assessed by behavioral, electrophysiological and histological studies.

Results

in vitro experiments confirmed that incubating the nerves in aqueous extract of oleo gum rein of asafoetida increased the amplitude and decreased the latent period of nerve compound action potential (CAP). Nerve conduction velocity (NCV) and amplitude of CAP also improved in asafoetida treated animals. Histological and behavioral studies showed that asafoetida was able to facilitate the healing process in peripheral nerves.

Conclusions

in vitro experiments showed that asafoetida is a nerve stimulant and its administration in neuropathic mice exerted neuroprotecting effects through stimulating axonal regeneration and remyelination and decrement of lymphocyte infiltration.  相似文献   
108.
Background: The major immuno-modulating effects of Ganoderma lucidum include mitogenicity and activation of immune effector cells such as T cells, macrophages and natural killer cells resulting in the production of cytokines. Objective: The purpose of this study was to evaluate the expression of CD40 and CD80 by G. lucidum-treated human peripheral blood mononuclear cells. Methods: Monocytes were isolated and incubated at 37°C and 5% CO2 for 24 h and 48 h in the presence or absence of different concentrations of G. lucidum. Cells were then incubated with labelled monoclonal antibodies against CD14, CD40 and B7-1(CD80) molecules utilizing standard protocols, and analyzed by flow cytometry. Results: The results showed that incubation of monocytes with G. lucidum led to marked enhancement of CD40 and B7-1 expression in a dose- and time- dependent manner (p<0.001). G. lucidum was more effective in enhancing the expression of CD80 and CD40 molecules of cells obtained from females than male donors (p<0.001). Conclusion: G. lucidum enhanced the expression of CD40 and CD80 molecules on peripheral blood monocytic cells derived from both sexes in a dose-dependent manner, with a preferential higher effect on cells obtained from female donors.  相似文献   
109.

Background

The aim of this study is to evaluate the prognostic factors of overall survival (OS) after haematopoietic stem cell transplant (HSCT) in acute lymphoblastic leukaemia (ALL) patients using accelerated failure time (AFT), Cox proportional hazard (PH), and Cox time-varying coefficient models.

Methods

206 patients were enrolled after HSCH in Shariati Hospital between 1993 and 2007. There was evidence of marked departures from the proportional hazards assumption with two prognostic factors, relapse and chronic graft-versus-host disease (cGVHD) (P < .001). Performance among AFT and Cox''s models was assessed using explained variation and goodness of fit methods. Discrimination among the exponential, Weibull, generalized gamma (GG), log-logistic, and lognormal distributions was done using maximum likelihood and Akaike information criteria.

Results

The 5-year OS was 52% (95%CI: 47.3–56.7). Peak mortality hazard occurred at months 6–7 after HSCT followed by a decreasing trend. In univariate analysis, the data was better fitted by GG distribution than by other distributions. Univariate analysis using GG distribution showed a positive association between OS with acute graft-versus-host disease (aGVHD) (P = .021), no relapse (P < .001), cGVHD (P < .001), neutrophil recovery (P < .001) and platelet recovery (P < .001). Based on Cox PH models; however cGVHD and relapse were the predictive factors of OS (P < .001). Multivariate analysis indicated that, OS is related to relapse (P < .001) and platelet recovery (P = .037), where predictive power of Weibull AFT models was superior to Cox PH model and Cox with time-varying coefficient (R2 = 0.46 for AFT, R2 = .21 for Cox PH and R2 = .34 for Cox time-varying coefficient). Cox-Snell residual shows Weibull AFT fitted to data better than other distributions in multivariate analysis.

Conclusion

We concluded that AFT distributions can be a useful tool for recognizing prognostic factors of OS in acute lymphoblastic leukemia patients.  相似文献   
110.
Background: Varicella–zoster virus (VZV) causes herpes zoster and varicella (Chicken-pox), usually a mild disease which is diagnosed clinically with few complications. However, in neonates and healthy adults it can have a severe presentation. Herpes zoster results from VZV reactivation later in life. Objective: To determine the seroprevalence of VZV in elementary school children aged 6-10 years in Shiraz, Iran. Methods: A cross-sectional seroprevalence survey was conducted on 270 healthy subjects. All serum samples were investigated for immunoglobulin G (IgG) antibody against VZV using a commercial enzyme linked immunosorbent assay (ELISA). Results: Among the studied population, 175 (64.8%) had no detectable antibody levels. The overall seroprevalence rate was 35.2%. A breakdown of seropositivity to VZV according to age was as follows; 10 years old, 50%, 9 years old, 48.2%, 8 years old, 27.3%, 7 years old, 32.1%, and 6 years old, 13.2%. Conclusion: As VZV susceptibility in the studied age groups was higher than the expected rate, therefore childhood VZV vaccination is recommended in our region.  相似文献   
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