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191.
192.
Water is a necessity for life. Currently, because of different contaminations in tap water, most people prefer using bottled mineral waters. Pesticides (e.g., organophophorous, carbamates, etc.) are among the most dangerous chemicals that may be found in drinking waters, which can cause long- and short-term complications. Because all people consume at least 2?L of water per day, water-quality monitoring is vital. In this study, we determined the concentration of three pesticides (aldicarb, parathion, and thiobencarb) in 13 tap-water samples collected from 13 different urban areas and 10 samples of bottled mineral water in Mashhad, a major city in northeast Iran. Samples were analyzed by gas chromatography coupled with a pulsed flame photometric detector after solid-phase extraction. Results showed that 2 of 13 tap-water samples and 2 of 10 bottled mineral water trademarks were contaminated either by parathion or by thiobencarb or both, with concentrations ranging between 0.6 and 0.8 ppb. According to the defined guideline values, determined concentrations of pesticides are below the permissible World Health Organization level for these toxic agents, and it is considered that drinking these tap waters and bottled mineral waters are safe for human consumption.  相似文献   
193.
The aim of this study was to prepare spray dried inhalable powders containing isoniazid-loaded chitosan/tripolyphosphate (TPP) nanoparticles for sustained delivery of the drug to the lung. Nanoparticles were prepared by ionic gelation method. In-vitro drug release study indicated that the rate of drug release from nanoparticles was decreased by increasing the amount of chitosan. Entrapment of isoniazid into chitosan/TPP nanoparticles decreased minimum inhibitory concentrations (MIC) of the drug against mycobacterium avium intracellulare. Nanoparticles were spray dried using excipients such as lactose, mannitol and maltodextrin alone or with leucine. Results showed that the obtained powders had different aerosolization property. It was observed that by adding leucine, the particle size of microparticles deceased and the process yield and fine particle fraction (FPF) increased significantly. The in-vitro deposition data indicated that spray drying of isoniazid-loaded nanoparticles with lactose in the presence of leucine resulted in the production of inhalable powders with the highest FPF (45%).  相似文献   
194.
BackgroundRestless legs syndrome (RLS) is a common disorder in hemodialysis patients that leads to insomnia and impaired quality of life. Because high oxidative stress has been implicated in the pathogenesis of RLS, we sought to evaluate the efficacy of vitamins C and E and their combination in reducing the severity of RLS symptoms in hemodialysis patients in this randomized, double-blind, placebo-controlled, four-arm parallel trial.MethodsSixty stable hemodialysis patients who had all four diagnostic criteria for RLS developed by the International Restless Legs Syndrome Group with no acute illness or history of renal stone were randomly allocated to four fifteen-patient parallel groups to receive vitamin C (200 mg) and vitamin E (400 mg), vitamin C (200 mg) and placebo, vitamin E (400 mg) and placebo, and double placebo daily for eight weeks. International Restless Legs Scale (IRLS) scores were measured for all patients at baseline and at the end of treatment phase. The primary outcome was absolute change in IRLS sum score from baseline to the end of treatment phase.ResultsMeans of IRLS sum score decreased significantly in the vitamins C and E (10.3 ± 5.3, 95% CI: 7.4–13.3), vitamin C and placebo (10 ± 3.5, 95% CI: 8.1–11.9), and vitamin E and placebo groups (10.1 ± 6, 95% CI: 6.8–13.5) compared with the double placebo group (3.1 ± 3, 95% CI: 1.5–4.8), (P < 0.001); however, no differences were observed between these treatment groups.ConclusionsVitamins C and E and their combination are safe and effective treatments for reducing the severity of RLS in hemodialysis patients over the short-term.  相似文献   
195.
We prepared different neutral and positively charged niosomal formulations containing sorbitan esters for entrapment of caffeine. Drug entrapment reduced following the incorporation of positively charged molecule. Furthermore, the span 60-containing niosomes showed the highest drug encapsulation efficiency due to solid-state nature of this surfactant's bilayers. There was a regular relationship between lipophilicity (HLB values) of surfactants and mean particle sizes; increasing the HLB value resulted in larger niosomes. By means of diffusion experiments with Franz diffusion cells, the effects of different vesicular components and that of the positive charge on the release of caffeine from various vesicle formulations were studied. Obtained results indicate that a combined erosion-diffusion mechanism regulates the permeation of caffeine through cellulose acetate membranes. High encapsulation efficiency, appropriate size distribution, and good vesicular stability, especially in solid state niosomes, make this type of vesicular systems a good alternative to liposomes for topical delivery of caffeine.  相似文献   
196.

Background

Cardiovascular disease (CVD) is one of the most important causes of death in developing countries. The current study evaluates the serum 25-hydroxyvitamin D (25OHD), phosphate and calcium levels in patients with angiographically-defined coronary artery disease (CAD) and healthy subjects in a sample population in northeastern Iran.

Methods

There were 566 subjects aged between 20–80 years out of whom283 subjects with CAD were divided into two study groups based on their angiogram results; those with?>?50% stenosis of one or more coronary arteries and those with?≤?50% stenosis. Serum 25OHD levels and anthropometric parameters were measured for all subjects.

Results

There were approximately 53% (n?=?303) males and 47% (n?=?269) females in the population sample. We found that crude serum 25OHD concentrations were significantly higher in both the Angio? (21.6?±?11.8?ng/ml) and Angio+ (21.3?±?10.2?ng/ml) groups compared to the control subjects (16.4?±?9.5?ng/ml) (P?<?0.001).

Conclusion

The findings show that 25OHD state could be a risk factor for CAD, although this would need to be explored further, taking the potential confounding effects of diet into account in future studies.  相似文献   
197.
Pregnant women suffering chronic illness or obstetric complications such as obesity are prone to severe pneumonia and COVID‐19. Obesity in pregnancy is associated with many complications for both mother and fetus. Here, we report the death of an obese mother with COVID‐19.  相似文献   
198.
A 34‐year‐old female patient presented with recurrent bilateral hypopigmented macules on the labia majora. The lesions were treated with topical steroids, which led to mild improvement, but erosive plaques developed after discontinuing the treatment. Histopathological findings were compatible with extramammary Paget disease (EMPD), which was treated with radical vulvectomy with no recurrence in the next months of follow‐up.  相似文献   
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