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961.
Diazinon (DZN) is an organophosphate pesticide widely used in agricultural to control insects and in veterinary medicine to control ectoparasites. This study investigated the induction of oxidative stress in the brain, heart, and spleen of Wistar and Norway rats treated with acute doses of DZN. Female Wistar and Norway rats were treated with 25, 50, 100, and 200?mg/kg of DZN by intraperitoneal injection. The animals were sacrificed 24?h after treatment, and tissues were isolated and analyzed. The result of this study shows that DZN at higher doses increased the level of malondialdehyde, superoxide dismutase and glutathione S-transferase activities and decreased glutathione (GSH) level, lactate dehydrogenase, and cholinesterase activities in the brain, heart, and spleen of both rat strains. At these concentrations, DZN toxicity also lead to a significant decrease in catalase (CAT) activity in all tissues of Wistar rat and brain of Norway rat, while it increased heart CAT activity in Norway rat. However, the alteration of these parameters was observed at lower doses of DZN in Wistar rat. These results suggest that DZN at higher doses induces the production of free radicals and oxidative stress in rat tissues and strains by alteration of antioxidant enzyme activity, depletion of GSH, and increasing lipid peroxidation. Induction of oxidative stress in DZN-treated rats is in the order of brain > heart > spleen. Wistar rats appear to be more sensitive to the effects of DZN on oxidative stress induction compared to Norway rat.  相似文献   
962.
Background: Global estimates suggest there are 15.6 million people who inject drugs (PWID) of whom 17.8% are living with HIV.Few studies have characterized newly-onset injectors with long-term injectors and its association with injecting risk behaviors. Objectives: We examined the relationship between length of injection and risk behaviors among people who inject drugs (PWID) in Tehran, Iran. Methods: A cross-sectional study was conducted among PWID, from March to August 2016 in Tehran, Iran. PWID were recruited by convenience and snowball sampling from five Drop-in Centers (DIC) located in the south of Tehran. Our primary independent variable was length of injecting career, defined as the number of months since injecting initiation. Those defined as new injectors (were injecting for less than 18?months), and long-term injectors (as injecting drugs for more than 18?months). We reported the adjusted odds ratio (aOR) point estimate and 95% confidence interval (CI95%) as the effect measure. The level of significance used in multiple logistic regression model was 0.05. We used STATA v. 11 for all analyzes. Results: The analytical sample comprised of 500 participants (100% male). Mean (±SD) age of PWID with a length of injection history was 31.2?±?7.2?years. Overall, 270 (54%) (CI95%: 49.6%, 58.4%) of participants were long-term injectors. The average age of drug use initiation among long-term injectors group was lower as compared to new injectors group (31.2 vs. 29.4, p?<?0.001). The odds of distributive syringe sharing among new injectors were two times higher than long-term injectors (AOR = 2.1, 95% CI 1.4–4.7). The odds of receptive syringe sharing were lower among new injectors group (AOR = 0.7, CI95% 0.2–0.87), compared to long-term injectors. New injectors had higher odds of reusing their own syringes (OR = 2.8, 95% CI: 1.4–5.7; p?=?0.01). Conclusions: Improvements in harm reduction service provision can occur through taregted risk reduction education for new injectors focusing on reducing distributive syringe sharing among them.  相似文献   
963.
The main purpose of this investigation is increasing of the solubility and dissolution rate of Azithromycin by solid dispersion technique using Kolliphor P 237, Kolliphor P 338 and Kolliphor P 407. Kolliphor (P 237, P 338 and P 407) in various properties by weight {(1:0.5), (1:1), (1:1.5) and (1:2)}, utilizing solvent evaporation method. Dissolution studies carried out in phosphate buffer with pH 6.0 according to US pharmacopoeia method. The drug release profiles were studied, so we found that the dissolution rate of the drug (by calculating the dissolution parameters) was significantly increase compared to pure drug, also solubility of physical mixtures as well as solid dispersions increased compared to the intact drug. For example solubility of the drug increased from 85–753 μg mL?1 (for Kolliphor P 237; 8 times more). The best results were as follows: Kolliphor P 237 > Kolliphor P 338 > Kolliphor P 407. IR spectra revealed no chemical incompatibility between drug and polymer. Drug-polymer interactions were investigated using differential scanning calorimetry, powder X-ray diffraction and scanning election microscopy. The dissolution rate and solubility of Azithromycin solid dispersions was improved significantly using Kolliphor. In addition, the simplicity of this method is very effective and have been met the project objectives.  相似文献   
964.
IntroductionConversion in the metabolism of drugs occurs in diabetes mellitus. Considering the importance of metabolic enzymes’ activities on the efficacy and safety of medicines, the changes in liver enzymatic activity of CYP2D1 and its related hepatic clearance, by using Dextromethorphan as probe in the animal model of type I and type II diabetes, before and after treatment, was assessed in this study.MethodsMale Wistar rats were randomly divided into 6 groups. Seven days after induction of diabetes type I and type II, treatment groups were received insulin and metformin daily for 14 days, respectively. In day 21, rats were subjected to liver perfusion by Krebs-Henseleit buffer containing Dextromethorphan as CYP2D1 probe. Perfusate samples were analyzed by HPLC fluorescence method in order to evaluate any changes in CYP2D1 activity.ResultsThe average metabolic ratio of dextromethorphan and hepatic clearance were changed from 0.012 ± 0.004 and 6.3 ± 0.1 in the control group to 0.006 ± 0.0008 and 5.2 ± 0.2 in the untreated type I diabetic group, and 0.008 ± 0.003 and 5.0 ± 0.6 in the untreated type II diabetic rats. Finally, the mean metabolic ratio and hepatic clearance were changed to 0.008 ± 0.001 and 5.4 ± 0.1, and 0.013 ± 0.003 and 6.1 ± 0.4 in the treated groups with insulin and metformin, respectively.ConclusionIn type I diabetic rats, corresponding treatment could slightly improve enzyme activity, whereas the hepatic clearance and enzyme activity reached to the normal level in type II group. Graphical abstractOpen in a separate window.  相似文献   
965.

Background

There are contradictory reports on the relationship between acne vulgaris and cigarette smoking. The objective of this study was to examine the relation between acne and cigarette smoking in a case-control study.

Methods

A questionnaire on smoking habits was offered to 350 patients with acne vulgaris and 350 patients suffering from skin diseases other than acne, aged 15 – 40 years, attending in a skin clinic in Tehran, Iran. The patients completed the questionnaires anonymously in the waiting room.

Results

Two hundred and ninety-three patients with acne (response rate 83.7 %) and 301 patients with other skin diseases (response rate 86.0 %) completed the questionnaires. Twelve acne patients (4.1 %) and 27 control patients (9.0 %) were current smokers (odds ratio = 0.43, 95% confidence limits 0.22 – 0.87, p < 0.05). But after adjustment for sex, this difference was not significant (odds ratio: 0.61, 95% CI: 0.30–1.26, p > 0.05, Mantel-Haenszel test).

Conclusion

An association between acne and cigarette smoking was not found in this study.  相似文献   
966.
Purpose: This study evaluated the curing efficiency of light-emitting diode (LED) and halogen [quartz tungsten halogens (QTH)] lights through ceramic by determining the surface microhardness of a highly filled resin cement.
Materials and Methods: Resin cement specimens (Variolink Ultra; with and without catalyst) (5-mm diameter, 1-mm thick) were condensed in a Teflon mold. They were irradiated through a ceramic disc (IPS Empress 2, diameter 5 mm, thickness 2 mm) by high-power light-curing units as follows: (1) QTH for 40 seconds (continuous), (2) LED for 20 seconds, and (3) LED for 40 seconds (5-second ramp mode). The specimens in control groups were cured under a Mylar strip. Vickers microhardness was measured on the top and bottom surfaces by a microhardness tester. Data were analyzed using analysis of variance (ANOVA) and a post hoc Bonferroni test at a significance level of p < 0.05.
Results: The mean microhardness values of the top and bottom surfaces for the dual-cured cement polymerized beneath the ceramic by QTH or LED (40 seconds) were significantly higher than that of light-cured cement ( p < 0.05). The top and bottom surface microhardness of dual-cured cement polymerized beneath the ceramic did not show a statistically significant difference between the LED and QTH for 40 seconds ( p > 0.05).
Conclusions: The efficiency of high-power LED light in polymerization of the resin cement used in this study was comparable to the high-power QTH light only with a longer exposure time. A reduced curing time of 20 seconds with high-power LED light for photopolymerizing the dual-cured resin cement under ceramic restorations with a minimum 2-mm thickness is not recommended.  相似文献   
967.
968.
Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease that may also be transmitted through person-to-person transmission by exposure to infected body fluids. Despite its wide geographic distribution in animals, CCHF virus is rarely associated with recognized human diseases. We report the first case of CCHF in Kermanshah province, Iran. Clinical presentation was characterized by fever, myalgia, and hemorrhage. The levels of liver enzymes, creatinine phosphokinase, and lactate dehydrogenase were elevated, and bleeding markers were prolonged.  相似文献   
969.
970.
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