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71.
Experimental findings suggest a protective role for cyclic nucleotides against induction of oxidative stress in saliva. Oxidative stress is a major contributor to the pathogenesis of inflammatory diseases. This study was conducted to evaluate salivary oxidative stress along with cGMP and cAMP levels in periodontitis subjects. cAMP and cGMP are second messengers that have important roles in salivary gland functions. Unstimulated whole saliva samples were obtained from periodontitis patients and age- and sex-matched healthy individuals. Saliva samples were analyzed for thiobarbituric reactive substances (TBARS) as a marker of lipid peroxidation, ferric reducing ability (total antioxidant power, TAP), and levels of cAMP and cGMP. Concentrations of cAMP and cGMP were reduced in the saliva of patients with moderate and severe periodontitis. Saliva of patients with severe periodontitis had higher TBARS and lower TAP than control subjects. The presence of oxidative stress and lower levels of salivary cGMP and cAMP in periodontitis are in association with disease severity.  相似文献   
72.
Clinical use of morphine in pain management is a controversial issue. Both nicotine and morphine are widely abused. So, investigating the interaction between nicotinic and opioid receptors is of great interest to both basic mechanistic and clinical view. We investigated the influence of repeated administration of nicotine on the development of morphine tolerance and dependence. Adult male albino mice were rendered dependent on morphine by subcutaneous (s.c.) injections three times daily for 3 days. Repeated intraperitoneal (i.p.) injection of nicotine (0.001-2 mg/kg) or saline (1 ml/kg) was performed 15 min prior to each morphine injection. Maximal possible effect (MPE%) of morphine (50 mg/kg; s.c.) was used on the fourth day as an index for the development of tolerance. Likewise, to assess the occurrence of dependence in drug-treated mice, naloxone (5 mg/kg; i.p.) was injected 2 h after the last dose of morphine. Repeated nicotine administration significantly attenuated the development of tolerance in a dose-dependent manner whereas it significantly decreased withdrawal jumping behavior in a biphasic profile (V-shape) manner. Furthermore, the central nicotinic receptor antagonist mecamylamine (0.01-0.1 mg/kg; i.p.) neither the peripheral nicotinic receptor antagonist hexamethonium (0.01 and 0.1 mg/kg; i.p.) nor the muscarinic receptor antagonist atropine (2.5-10 mg/kg; i.p.), dose-dependently antagonized both the inhibition of withdrawal jumping as well as increase in MPE% which was produced by repeated nicotine administration (0.1 mg/kg; i.p.). On the other hand, 3 days of solely nicotine treatment resulted in significant jumping behavior precipitated by naloxone after single morphine injection on the test day. The data suggests that the inhibitory effect of nicotine on the morphine tolerance and dependence is mediated by central nicotinic receptors and there is a cross-dependence between nicotine and morphine.  相似文献   
73.
Annals of Nuclear Medicine - Hepatotoxicity remains amongst the restricting factors of Methotrexate (MTX)-associated cancer therapy, especially in high doses of chemo-drugs or prolonged treatment....  相似文献   
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Bacterial biofilms are aggregates of bacterial cells embedded in a self-produced extracellular polymeric matrix. Biofilm formation has always been considered a major challenge for sensors used in underwater measurements, and is a primary source of measurement error, especially when it comes to long-term in situ monitoring. We demonstrate the utility of lytic bacteriophages (bacterial viruses) as a non-invasive strategy for removing bacterial biofilms formed on the gas permeable membrane of electrochemical dissolved oxygen sensors. Our results show that a 4 day Pseudomonas aeruginosa biofilm with a fully developed matrix significantly affected the sensor signal and response time, decreasing the signal by 32% and increasing the response time by 94%. In addition, measurements with the biofouled membrane had a very low signal to nose ratio compared to a clean sensor membrane. A single dose of overnight phage treatment effectively removed the biofilm (as indicated by scanning electron micrographs and fluorescence images of the membrane), without the need for repeated treatments. Furthermore, the sensor signal that had plummeted by 32% for a fully biofouled membrane, was returned to the original value (7.96 ± 0.27 mg L−1) after phage treatment and the signal to noise ratio (calculated as the ratio of mean to standard deviation) increased 8 folds for a phage-treated membrane compared to a biofouled membrane. Our data indicate near complete regeneration and signal recovery for the dissolved oxygen sensor, making the biofouled sensor reusable without the use of harsh chemicals that could destroy the fragile sensor membrane.

Lytic bacteriophages can be utilized as a non-invasive method for removing bacterial biofilms formed on the surface of gas permeable membranes of dissolved oxygen sensors.  相似文献   
76.
From July to December 2003, four categories of diarrhoeagenic Escherichia coli were investigated in Tehranian children with acute diarrhoea. Stool specimens of children under 5 years of age with diarrhoea (n=200) and matched controls (n=200) without diarrhoea were studied for the presence of entero-aggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC) and Shiga toxin-producing (STEC) E. coli by PCR identification of six different genes of diarrhoeagenic E. coli. STEC isolates were typed by O157 and H7 antisera. EAEC was the most prevalent category and was found in 24% of patients with diarrhoea and 8% of controls (p<0.0001). ETEC was isolated in 15.5% of patients with diarrhoea but not in any controls ( p<0.0001), STEC in 15% of patients and 2% of controls (p<0.0001) and EPEC in 6% of patients and 5% of controls. Of 30 STEC isolates from patients with diarrhoea, seven were O157:H7 and 23 were non-O157:H7.  相似文献   
77.
This study aimed to investigate the association between self-rated mental health (SRMH) and current health status of an Iranian population. A cross-sectional study was conducted on 3400 individuals selected through random sampling in Shiraz, Iran between January 2014 and March 2015. Data were gathered through face-to-face interviews. Statistical analyses were performed using the SPSS 19.0, and R.3.1.2 software was used for SCAD penalized logistic regression. The mean age of the participants was 38.5 (±?14.1 years). There were significant relationships between better SRMH and younger ages (p?<?0.001), and between better SRMH and better self-rated physical health (p?<?0.001). Individuals with poor SRMH were more likely to have signs and symptoms of medical diseases. SRMH, a component of self-rated health, was related to a variety of health problems in our study population. Therefore, paying attention to SRMH and mental well-being could be useful in making decision about implementation of preventive measures.  相似文献   
78.

Background/Objective

Genital warts are caused by human papilloma virus (HPV) and usually have no promising cure. Garlic (Allium sativum) belongs to Liliaceae family, which has a long history of medicinal use. The garlic extract had antiviral and anticarcinogenic effects and can be effective on complete resolution of cutaneous wart. The aim of this clinical study was to compare the garlic extract effect with cryotherapy in the treatment of male genital wart.

Methods

35 male patients aged 20–54 years old with clinically diagnosed genital warts who had more than two warts on both sides of genital region enrolled in the study. Cryotherapy with liquid nitrogen (?196 °C temperature) was performed for all right sided warts and 10% garlic extract was applied on all left-sided warts for 2 months.

Results

Regarding response to treatment, at the end of weeks 2, 4, 6 and 8 there was no significant difference between two groups (P > 0.05). 69.7% and 78.8% of patients showed complete clearing of the lesions in the garlic and cryotherapy groups respectively (P value, 0.39).

Conclusions

The present study revealed 10% garlic extract after 2 months duration therapy on the male genital warts had the similar effect in compare to cryotherapy.  相似文献   
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