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991.

Background:

Parasitological investigations on paramphistomosis were carried out over a 12-month period in the southeast of Iran to determine the prevalence and intensity of this disease.

Methods:

A total of 1000 cattle, Sistani breed (n= 450) and Brahman breed (n= 550) of all sex and age groups were inspected at random for the presence of paramphistomidae flukes in Zabol slaughterhouse from December 2012 to October 2013.

Results:

Paramphistomes were found in 369 of 1000 necropsied cows (36.9%; 95% CI: 30.1–41.9%), with significant higher prevalence of infection in Brahman breed than in Sistani breed (51% vs 19.3%). No significant correlation between prevalence, intensity of infection, sex and age of cattle was noted. Despite the difference in the seasonal variations of prevalence, and the relation between the intensity of infection and season, these were not statistically significant. The mean intensity of infection in Brahman breed was higher (652.66 ± 281.5) than Sistani breed (123.32 ± 32.2). The identification of stained trematodes to the species revealed 40, 20, 20, 15 and 5% Gastrothylax crumenifer, Cotylophoron cotylophorom, Paramphistomum cervi, Carmyerius spatiosus, Explanatum explanatum, respectively.

Conclusion:

The present results will contribute to our understanding of the epidemiology of paramphistomumosis in southeastern Iran.  相似文献   
992.

Background:

Parasitic intestinal infections are still among socioeconomic problems in the world, especially in developing countries like Iran. Food-handlers that directly deal with production and distribution of foods between societies are one of the most important sources to transmit parasitic infections to humans. The aim of this study was to determine the prevalence of intestinal parasitic infections among food-handlers in Shiraz, Iran.

Methods:

In this cross-sectional study, 1021 feces samples were randomly collected from food-handlers in Shiraz, central Iran from August to September 2013. Two different methods, routine direct fecal examination and Formalin –Ethyl acetate concentration as a complementary technique, were done to detect parasites.

Results:

The prevalence of parasitic organisms was 10.4% in the food-handlers. The most species of the protozoan parasites were G. lamblia, E. coli and B. hominis; meanwhile, only one infection by H. nana (0.1%) was detected in this group. Mixed infections were observed in 13.2% (n=14/106) of positive cases. The majority of participants were male (57%); however, data analysis showed significant statistical difference in the rate of infection between females 11.9% (n=53/444) and males 9% (n=52/577) (P=0. 024). There was no significant statistical difference in the rate of infection among different educational and occupation groups.

Conclusion:

Although decreasing of helminthic infections is distinct, but infecting with protozoan parasites is still important in food-handlers. Concentration technique is more useful than direct smear technique, especially for detection parasites in low number. High level of education in our study showed that training courses in this group could be effective in the implementation of control and prevention programs.  相似文献   
993.

Background:

Dense granules are immunodominant proteins for the standardization of immunodiagnostic procedures to detect neosporosis. In the presented study different fragment of a dense-granule protein was evaluated for serodiagnosis of Neospora caninum in cattle and water buffalo.

Methods:

NcGRA7, from N. caninum tachyzoites was amplified. PCR product and pMAL-c2X plasmid were digested with EcoR1 restriction enzyme and expressed in Escherichia coli to evaluate its competence for detection of anti- N. caninum antibodies with ELISA in comparison with commercial IDEXX ELISA. Furthermore, 230 sera of presumably healthy cattle and water buffaloes (108 cattle and 122 water buffaloes) were analyzed by both tests to determine the agreement of these two procedures.

Results:

Sensitivities and specificities of NcGRA7-based ELISA were 94.64% and 90.38% respectively using sera of cattle, but were 98.57% and 86.54% in the case of buffaloes respectively. A good correlation between the results of IDEXX ELISA and ELISA based on recombinant NcGRA7 for detecting N. caninum antibodies was appeared. Analyzing by Mc Nemar′s showed that NcGRA7-based ELISA has acceptable capability to differentiate the positive results in comparison with IDEXX ELISA.

Conclusion:

NcGRA7-based ELISA considering utilized new fragment of genomic DNA is a good tool for serodiagnosis of anti- N. caninum antibodies for screening and epidemiological purposes on cattle herd and water buffaloes as well.  相似文献   
994.

Background:

This study was undertaken to evaluate the viability, infectivity and immunity of Toxoplasma gondii tachyzoites exposed to 2-(naphthalene-2-ylthio)-1H-indole.

Methods:

Tachyzoites of RH strain were incubated in various concentrations of 2-(naphthalene-2-ylthio)-1H-indole (25–800 μM) for 1.5 hours. Then, they were stained by PI and analyzed by Fluorescence-activated cell sorting (FACS). To evaluate the infectivity, the tachyzoites exposed to the different concentrations of the compound were inoculated to 10 BALB/c mice groups. For Control, parasites exposed to DMSO (0.2% v/v) were also intraperitoneally inoculated into two groups of mice. The immunity of the exposed tachyzoites was evaluated by inoculation of the naïve parasite to the survived mice.

Results:

The LD50 of 2-(naphthalene-2-ylthio)-1H-indole was 57 μmol. The longevity of mice was dose dependent. Five mice out of group 400μmol and 3 out of group 800μmol showed immunization to the parasite.

Conclusion:

Our findings demonstrated the toxoplasmocidal activity of the compound. The presence of a well-organized transporter mechanism for indole compounds within the parasite in conjunction with several effective mechanisms of these compounds on Toxoplasma viability would open a window for production of new drugs and vaccines.  相似文献   
995.
The initial and long-term benefits of coronary artery bypass grafting depend upon maintaining the coronary blood flow supplied by the graft. In order to devise a scoring system for predicting graft patency, we evaluated presumptive correlations between saphenous vein graft patency and the characteristics of saphenous veins that were used as conduits in coronary revascularization.We prospectively evaluated 1,000 saphenous vein segments that were implanted in 403 consecutive patients who underwent on-pump coronary artery bypass grafting at our hospital from January 2006 through February 2009. Branches, varicosity, diameter, and wall thickness were evaluated, and a scoring system was created in order to obtain a value for each characteristic. The patients were postoperatively monitored for 1 year, and graft patency was then evaluated with the use of 64-slice multidetector computed tomography.Lesions were found in 12.3% of the grafts. All of the evaluated characteristics of the grafts had a significant correlation with saphenous vein graft flow (P <0.0001). Using the venous characteristics in our statistical analysis, we devised a formula to obtain a score (range, 4-12) to predict the patency of each graft. A cutoff score of 7 yielded 87.8% sensitivity and 82.8% specificity.Our scoring system has good prognostic value. We believe that it can assist surgeons in choosing the most appropriate conduit and target vessel for coronary artery bypass grafting, especially in high-risk patients who are particularly dependent on blood flow through saphenous vein grafts.  相似文献   
996.

Background and Aims

Determining the stage of liver fibrosis and the grade of necroinflammation is important in predicting the prognosis and treatment response of patients with chronic viral hepatitis. Liver biopsy is associated with several technical problems and complications; therefore, its repetitive performance as a procedure in evaluating treatment response and in following up patients is not recommended. This study was performed to determine the correlation of serum hyaluronic acid (HA) levels with the stage and grade of histopathologic liver changes in patients with chronic hepatitis B and C.

Methods

This analytical cross-sectional study was performed on 69 patients with chronic hepatitis B or C in Mashhad, Iran, who were referred to our clinic and underwent liver biopsy and blood sampling simultaneously in 2006-2007. None of the patients were on medication that would affect the serum levels of (HA) and patients with signs of arthropathy were excluded from the study.

Results

Out of the 69 patients i this study, 48 (69.6%) were male and 21 (30.4%) were female. The causative virus in 29 patients (42%) was hepatitis C and in the rest (n = 40, 58%) hepatitis B. The severity of liver fibrosis (stage) had a direct correlation (r = 0.25, P = 0.042) with the levels of (HA) and an inverse correlation with the platelet level (r = 0.37, P = 0.002). The degree of liver necroinflammation (grade) did not have a significant correlation with the levels of (HA) and alanine transaminase (r = -0.01, P = 0.9; r = 0.21, P = 0.09 respectively); instead, there was an inverse correlation with platelet levels (r = 0.36, P = 0.003).

Conclusions

Our study results correspond with those of other international studies; thus suggesting that the (HA) serum level is a useful marker in determining the severity of fibrosis in patients with chronic viral hepatitis. To form a definite conclusion, further studies on large groups should be performed.  相似文献   
997.
998.
ObjectiveTo determine the susceptibility of main malaria vector in Astra County, borderline of Iran and Republic of Azerbaijan for better control.MethodsSusceptibility of Anopheles maculipennis to diagnostic doses of DDT 4%, dieldrin 0.4%, malathion 5%, lambdacyhalothrin 0.1%, and delamethrin 0.025%, was tested according to method recommended by WHO. All the impregnated papers were provided by WHO.ResultsIt was shown that this species exhibited resistance to DDT, dieldrin, whereas susceptible to malathrion, lambdacyhalothrin and deltamethrin.ConclusionsFindings of susceptibility tests of this species provided a clue for control of malaria vector in the region.  相似文献   
999.
ObjectiveTo explore the antibacterial effect of the alcoholic extracts of aerial parts of Teucrium polium, native in Iran on some pathogenic bacteria.MethodsAntibacterial activity of ethanolic extract (50 to 400 mg/mL) and methanolic extract (400 and 600 mg/mL) was evaluated by disc diffusion method.ResultsThe ethanolic extract results showed that Bacillus anthracis was the most sensitive species, while Escherichia coli and Proteus mirabilis were more resistant than others. In the case of the methanolic extract, Bordetella bronchiseptica was the most sensitive and Proteus mirabilis and Arcanobacterium pyogenes were the most resistant species. The hydroalcoholic extract of Teucrium polium had a relatively satisfactory effect on Salmonella typhi. The minimal inhibitory concentration (MIC) of Staphylococcus aureus and Salmonella typhi was 40 mg/mL and Bordetella bronchiseptica and Bacillus anthracis was 10 mg/mL. The minimal bactericidal concentration (MBC) against Bacillus anthracis was 10 mg/mL while against other species were not found (>200 mg/mL). The methanolic extract had also synergistic effect with methicillin, vancomycin against Staphylococcus aureus and with novobiocin against Salmonella typhi.ConclusionsThese results suggest that this plant contains relatively good antibacterial activity and it can be used as a source of antiseptic compounds for medicinal uses.  相似文献   
1000.
ABSTRACT

Objective: Serine/arginine-rich splicing factor 2 (SRSF2) mutations were detected frequently in myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia (CMML) patients. However, its prognostic value has not yet been fully clarified.

Methods: In this meta-analysis, Hazard Ratio (HR) and 95% confidence interval (CI) for overall-survival (OS) were chosen to evaluate the prognostic impact of SRSF2 mutations and to compare SRSF2 mutations to those with wild-type.

Results: A total of 2056 patients from 12 studies were obtained. The pooled HRs for OSsuggested that patients with MDS had a poorer prognosis (HR?=?1.780, 95% CI (1.410–2.249)), while analysis on SRSF2 mutations revealed no significant effect on the prognosis of CMML patients (HR?=?1.091, 95% CI (0.925–1.286)). The frequency of SRSF2 mutations was found to be 11.5% and 39.8% in patients with MDS and CMML, respectively.

Discussion: This meta-analysis suggests that SRSF2 has a poor prognosis in patients with MDS, but no prognosis impact on patients with CMML.

Conclusion: In conclusion, SRSF2 mutations were significantly related to the shorter OS in patients with MDS which may consider as an adverse prognostic risk factor. Whereas, analysis did not show any prognostic effect on OS of CMML patients with SRSF2 mutations.  相似文献   
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