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31.
Interleukin 6 (IL-6) has been shown to be related to the pathogenesis of systemic lupus erythematosus (SLE). In the present study, the relationship between two polymorphisms in the promoter region of IL-6 gene at positions −572 G/C and −174 G/C and disease susceptibility in 401 Iranian patients with SLE was investigated using polymerase chain reaction–restriction fragment length polymorphism method. The genotype distribution and allele frequencies of IL-6 gene polymorphism at −174 position showed no significant difference between SLE patients and controls. In contrary, both allelic and genotypic frequencies at the −572 position significantly differed in SLE patients and controls. At this position, GG genotype was observed in 77.9% of patients compared to 68.9% in the control group (p < 0.014). The frequency of −572 G allele in patients (87.3%) was also higher than in controls (83.2%; p = 0.034). The haplotype study showed no significant difference between patients and healthy subjects. Study of the relationship between these polymorphisms and clinical manifestations and laboratory parameters showed an association between −174 polymorphism and the presence of antinuclear antibodies in all patients and rash and hematuria in male patients (p < 0.04). At −572 polymorphism, a significant difference with regard to photosensitivity in male patients (p = 0.04) was found. In conclusion, results of this study showed that −572 polymorphism plays an important role in susceptibility to SLE and that −174 polymorphism could influence the presence of antinuclear antibodies in the patients.  相似文献   
32.
ObjectiveTo guide for selection of plants with antibacterial activity for further phytochemical works on the isolation and identification of the active compounds.MethodsEthanolic extracts of 3 species from Malvaceae family were evaluated by agar disc diffusion method for antibacterial activity against some gram-positive and gram-negative bacteria (Pseudomonas aeruginosa, Listeria monocytogenes, Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella pneumoniae, Salmonella typhi, Bacillus cereus, Bacillus anthracis, Escherichia coli Streptococcus pyogenes). The extracts were obtained from aerial parts of Hibiscus rosa (H. rosa)-sinensis (leaf and flower), Alcea rosea (A. rosea) L. (leaf and flower) and Malva neglecta (M. neglecta) Wallr (flower).ResultsThese extracts had inhibitory effects at different concentrations (0.05, 0.10, 0.20 and 0.40 g/mL) against above mentioned bacteria. Escherichia coli was the most resistant strain. The highest inhibitory zone was showed by ethanolic extract of M. neglecta against Staphylococcus epidermidis (22 mm) and followed by ethanolic extract from flower of H. rosa against Staphylococcus epidermidis and Staphylococcus aureus (20 mm). The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values against Staphylococcus epidermidis were equal (MIC=MBC=5 mg/mL for M. neglecta extract and for H. rosa extract MIC=MBC=20 mg/mL).ConclusionsThese findings suggest that these native plants have good antibacterial properties that can be used for infection control and treatment and could also be as new source for antibiotics discovery and infection treatment.  相似文献   
33.
Classifying brain white matter fibers into bundles is of growing interest in neuroscience. Quantification of diffusion characteristics inside a fiber bundle provides new insights for disease evolutions, therapy effects, and surgical interventions. In this paper, we present a novel method for segmenting fiber bundles using spherical harmonic coefficients (SHC) that describe diffusion signal obtained from High Angular Resolution Diffusion Imaging (HARDI) protocols. Based on SHC, we define a similarity measure and use it as a speed function term in level set framework. We show advantages of the proposed measure over similarity measures based on Diffusion Tensor Imaging (DTI) indices. Without any assumptions about diffusion model, we deal with diffusion signal instead of orientation distribution function (ODF) calculated using complicated mathematics, inaccurate simplifications, and time-consuming implementation. By applying the proposed algorithm on synthetic data, its superior accuracy and robustness in low SNR conditions are shown. Application of the proposed method on real HARDI MRI data also illustrates its superior performance, especially in heterogeneous diffusion areas with low traditional diffusion anisotropies.  相似文献   
34.
AIM: To study the clinical and laboratory characteristics of autoimmune hepatitis (AIH), and compare them with International Autoimmune Hepatitis Group (IAHG) criteria. METHODS: Sixty consecutive patients with AIH attended the University Clinic at Tabriz University of Medical Sciences, Iran for a 12mo period and were assessed in a case series study. Serological and biochemical evaluations were carried out in all patients. Autoantibodies, such as antinuclear antibody (ANA), anti-smooth muscle antibody (ASMA), anti-liver-kidney microsomal antibody (ALKM-1) type 1, and perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA) were evaluated in these patients. A liver biopsy was performed after diagnosis of the disease. Patients were evaluated in terms of their signs and symptoms, and laboratory results and the degree to which they corresponded with the diagnostic criteria of IAHG. In this study, both a comprehensive diagnostic scoring system and a simplified diagnostic scoring system were employed for AIH.RESULTS: Sixty patients, 2-0 male, 40 female, mean age 39.45 ± 17.50 years, participated in the study. Treatment began immediately after enrolment into the study. The percent distribution of the study population into definite and probable did not change after the treatment. The most common symptoms in descending order were fatigue (100%), icter (66.7%), abdominal discomfort (33.3%), abdominal distension (2-8.3%), dark urine (2-3.3%), edema (2-3.3%), hematemesis (2-0.0%), pruritus (2-0.0%), melena (11.7%) and pale stool (10.0%). At the physical examination, splenomegaly, ascites, hepatomegaly, epigastric tenderness and an abdominal mass were found in 50.0%, 16.7%, 13.3%, 5.0% and 3.3% of patients, respectively. Hypergammaglobulinemia was detected in 95.0% of cases. ALKM-1, P-ANCA, ANA and ASMA were positive in 71.4%, 66.7%, 42-.4% and 19.4% of cases, respectively. Portal hypertensive gastropathy (45.0%), esophageal varices (41.7%) and cirrhosis (40.0%) were the most prevalent complications of AIH, and there was  相似文献   
35.

Background

This study aimed to assess the socioeconomic inequality and determinants of screen time (ST) frequency in Iranian children and adolescents.

Methods

This nationwide study was conducted as part of a national school-based surveillance program among 36,486 students consisting of 50.79% boys and 74.23% urban inhabitants, aged 6–18 years, living in urban and rural areas of 30 provinces of Iran. Socioeconomic inequality in ST, including the time spent for ST, watching TV and leisure-time working with computer, was assessed across quintiles of SES using concentration index (C) and slope index of inequality (SII).

Results

Overall, 36,486 students completed the study (response rate 91.25%). Their mean (SD) age was 12.14 (3.36) years. The national estimation of frequency of ST was 31.66% (95% CI 31.16–32.17) with ascending change from 20.80% (95% CI 19.81–21.82) to 36.66% (95% CI 35.47–37.87) from the first to the last quintal of SES. Estimated C value at national level was positive (0.08), which indicate inequality was in favor of low SES groups. Considering the SII values, at national level [? 0.16 (? 0.39, 0.06)], the absolute difference in ST frequency between the bottom and top of the socioeconomic groups had descending trends. In multivariate logistic regression model, family history of obesity, generalized obesity and age were the main significant determinants of prolonged ST, watching TV, and computer working (P < 0.001).

Conclusions

Socioeconomic inequality in ST frequency was in favor of low SES groups. These findings are useful for health policies, better programming and future complementary analyses.
  相似文献   
36.
37.
Platelet-rich fibrin (PRF) as a rich source of effective growth factors has been used as a scaffold in tissue regeneration. It is known that PRF exhibits rapid degradability against enzymes, which should be decreased using crosslinking agents to reduce the release rate of growth factors and increase the effectiveness of tissue regeneration. In this study, a carbodiimide crosslinker with different concentrations (0.01%, 0.05%, 1%, and 2%) was used to modify and improve the properties of PRF gel. The crosslinked gels were evaluated with analyses such as SEM, swelling, degradability, mechanical strength, release test, cytotoxicity, and cell adhesion. The results showed that with increasing crosslinker concentration, the morphology of the fiber structure changes drastically, the swelling rate decreases from 300% (control) to 160% for the crosslinked gel, the degradation time for the control sample increases from 8 days to more than two weeks for the crosslinked gel, and the Young''s modulus increases from 0.15 MPa (control) to 0.61 MPa for the crosslinked samples. Growth factors also showed lower release with increasing crosslinking ratio. Cytotoxicity assays demonstrated that by increasing the crosslinker concentration to 1% w/v, no cytotoxicity was observed. Cellular studies with DAPI staining showed that the cells penetrated well into the gels and were well distributed, especially in gels with lower crosslinker concentrations. In addition, the modified PRF gel can be used as a scaffold for tissue regeneration.

1-Ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC) as a crosslinker can improve the physical and mechanical properties of PRF gel by forming covalent bonds.  相似文献   
38.
Background: Insulitis is defined by the presence of immune cells infiltrating in the pancreatic islets that might progress into the complete β-cell loss. The immunomodulatory properties of bone marrow-derived mesenchymal stem cells(BM-MSCs) have attracted much attention. This study aimed to evaluate the possible immunomodulatory effects of rat BM-MSCs and MSCs-derived insulin-producing cells(IPCs) in a mouse model of pancreatic insulitis. Methods: Insulitis was induced in BALB/c mice using five consecuti ve doses of streptozotocin. MSCs or IPCs were directly injected into the pancreas of mice and their effects on the expression of Th subsetsrelated genes were evaluated. Results: Both BM-MSCs and IPCs significantly reduced the expression of pancreatic Th1-related IFN-γ( P 0.001 and P 0.05, respectively) and T-bet genes(both P 0.001). Moreover, the expression of IL-10 gene was significantly increased in IPC-treated compared to BM-MSC-or PBS-treated mice( P 0.001 both comparisons). Conclusions: BM-MSCs and IPCs could successfully suppress pathologic Th1 immune responses in the mouse model of insulitis. However, the marked increase in IL-10 gene expression by IPCs compared to BM-MSCs suggests that their simultaneous use at the initial phase of autoimmune diabetes might be a better option to reduce inflammation but these results need to be verified by further experiments.  相似文献   
39.
The occurrence of oxidative stress during the sperm freeze-thaw cycles affects the sperm parameters and eventually leads to a decrease in its reproductive potential. Sperm protection against oxidative reactions during freezing is done by antioxidants. Since the selection of a suitable sperm cryopreservation bank is effective in maintaining acceptable reproductive potential and motility of sperm during cryopreservation.This study aimed to evaluate the antioxidant effects of different doses of the extract of brown algae Sargassum on oxidative stress and frozen human sperm parameters.We conducted a randomized controlled trial on the semen samples from 11 healthy men in the age group of 25 to 36 years. The samples were collected by masturbation after 3 to 5 days of abstinence from ejaculation. The specimens were divided into 3 equal parts, including 1 control group and 2 experimental groups.The 2 experimental groups were frozen using the rapid solidification technique with Sargassum extract at doses of 250 and 500 μg/mL.Motility and morphology of sperms were measured using a computer system and CASA software and the amount of reactive oxygen species was determined using Oxisperm kit.Sargassum extract significantly decreased the amount of reactive oxygen species (P < 0.005) and at doses of 250 and 500 μg/mL, significantly increased the overall motility (P < 0.006) and progressive motility (P < 0.007) after solidification, but did not affect the normal morphology of sperms.The addition of ethanol extract of Sargassum prevents reactive oxygen species production during the solidification process and improves sperm motility at doses of 250 and 500 μg/mL.  相似文献   
40.
BackgroundCareful evaluation of the progression trend of the metabolic syndrome (MetS) in children and adolescents (C&A) is one of the important methods of studying the natural history of MetS in them. This study was performed to determine the trend of changes in the progression of MetS from its components.MethodsThis was a longitudinal study which was performed on data from 4 follow-up periods of Tehran Lipid and Glucose Study (TLGS) between 1999 and 2015. The research population consisted of 6-18-year-old children and adolescents creating 3895-person population. The criteria for the diagnosis of MetS was joint interim statement (JIS). The considered components were central adiposity, high blood pressure, insulin resistance, and dyslipidemia.ResultsIn this study, in the long term, the highest increase in the MetS’ incidence in boys occurred in obesity and in girls in dyslipidemia and in total mode, in obesity. But in the short term (3.6 year follow-up periods) in the first to fourth periods, in total mode, the highest incidence occurred in dyslipidemia, hyperglycemia, dyslipidemia, and obesity. In terms of trend, in total mode, the highest increase in MetS incidence was related to the obesity component. Also, the incidence of MetS from all components was declining in overall mode. Also, the most common components at the beginning and end of the study in all groups were dyslipidemia with a decreasing and obesity with an increasing trend, respectively.ConclusionIt seems that in Iranian C&As, obesity and dyslipidemia components play a more important role in the further development of the MetS than other components. This matter requires careful and serious attention in preventive and control planning.  相似文献   
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