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61.
The fungi Trichophyton mentagrophytes and T interdigitale account for significant amount of dermatophytosis cases worldwide. These two dermatophytes form a species complex and have a number of ribosomal internal transcribed spacer (ITS) region genotypes, allowing simultaneous species identification and strain typing. Our aim was to describe the geographic distribution of T mentagrophytes/T interdigitale ITS region genotypes and find an association between the genotypes and clinical presentations of respective infections. We performed rDNA ITS region sequencing in 397 Iranian T mentagrophytes/T interdigitale isolates and analysed all available in GenBank entries with sequences of this kind. For the study, 515 clinical annotations were available. Statistical analysis was performed by chi‐squared test and Spearman rank correlation analysis. A total of 971 sequences belonged to genotypes with at least 10 geographic annotations and were classified on the basis of exclusive occurrence in a particular region or high relative contribution to a regional sample. We discerned Asian and Oceanian (“ KU496915 ” Type V, “ KT192500 ” Type VIII, “ KU315316 ”), European (“ FM986750 ” Type III, “ MF926358 ” Type III*, “ KT285210 ” Type VI) and cosmopolitan (“ FM986691 ” Type I, “ JX122216 ” Type II, “ KP132819 ” Type II* and “ AF170453 ” Type XXIV) genotypes. There was statistically significant difference in the ITS genotype distribution between different affected body sites. Trichophyton mentagrophytes “ KT192500 ” Type VIII correlated with tinea cruris, T mentagrophytes “ KU496915 ” Type V correlated with tinea corporis, T interdigitale “ JX122216 ” Type II correlated with tinea pedis and onychomycosis. Trichophyton mentagrophytes and T interdigitale genotypes can be associated with distinct geographic locations and particular clinical presentations.  相似文献   
62.
63.
Estrogen receptor-?? (ER??) positive breast cancer frequently responds to inhibitors of ER?? activity, such as tamoxifen, and/or to aromatase inhibitors that block estrogen biosynthesis. However, many patients become resistant to these agents through mechanisms that remain unclear. Previous studies have shown that expression of ER?? in ER??-negative breast cancer cell lines frequently inhibits their growth. In order to determine the consequence of ER?? over-expression in ER??-positive breast cancer cells, we over-expressed ER?? in the MCF-7 breast cancer cell line using adenovirus gene transduction. ER?? over-expression led to ligand-independent expression of the estrogen-regulated genes pS2 and PR and growth in the absence of estrogen. Interestingly, prolonged culturing of these cells in estrogen-free conditions led to the outgrowth of cells capable of growth in cultures from ER?? transduced, but not in control cultures. From these cultures a line, MLET5, was established which remained ER??-positive, but grew in an estrogen-independent manner. Moreover, MLET5 cells were inhibited by anti-estrogens showing that ER?? remains important for their growth. Gene expression microarray analysis comparing MCF-7 cells with MLET5 highlighted apoptosis as a major functional grouping that is altered in MLET5 cells, such that cell survival would be favoured. This conclusion was further substantiated by the demonstration that MLET5 show resistance to etoposide-induced apoptosis. As the gene expression microarray analysis also shows that the apoptosis gene set differentially expressed in MLET5 is enriched for estrogen-regulated genes, our findings suggest that transient over-expression of ER?? could lead to increased cell survival and the development of estrogen-independent growth, thereby contributing to resistance to endocrine therapies in breast cancer patients.  相似文献   
64.

PURPOSE

Heat of composite polymerization (HP) indicates setting efficacy and temperature increase of composite in clinical procedures. The purpose of this in vitro experimental study was to evaluate the effects of 5 temperatures on HP of two new composites.

MATERIALS AND METHODS

From each material (Core Max II [CM] and King Dental [KD]), 5 groups of 5 specimens each were prepared and their total HPs (J/gr) were measured and recorded, at one of the constant temperatures 0℃, 15℃, 23℃, 37℃ and 60℃ (2 × 5 × 5 specimens) using a differential scanning calorimetry (DSC) analyzer. The data were analyzed using a two-way ANOVA, a Tukey''s test, an independent-samples t-test, and a linear regression analysis (α=0.05).

RESULTS

No polymerization reactions occurred at 0℃; then this temperature was excluded from statistical analyses. The mean HP of the remaining 20 KD specimens was 20.5 ± 14.9 J/gr, while it was 40.7 ± 12.9 J/gr for CM. The independent-samples t-test showed that there were significant differences between the HP of the two materials at the temperatures 15℃ (P=.0001), 23℃ (P=.0163), 37℃ (P=.0039), and 60℃ (P=.0106). Linear regression analysis showed statistically significant correlations between environment temperatures and HP of CM (R2=0.777).

CONCLUSION

Using CM is advantageous over conventional composite because of its better polymerization capacity. However due to its high HP, further studies should assess its temperature increase in vivo. Preheating KD is recommended. Refrigerating composites can negatively affect their polymerization potential.  相似文献   
65.
Objective: Systemic lupus erythematosus (SLE) as a chronic autoimmune disease has a worldwide distribution. There is a wide variation in the natural history of SLE among different ethnic and geographic groups. The aim of this study was to show the manifestations of SLE in Iranian patients. Methods: The study was on manifestations of SLE according to the database of the Rheumatology Research Center (RRC), Tehran, Iran, on registered patients during the period of 1976 to 2009. Results: A total of 2280 SLE patients (2052 female and 228 male) were studied. The female : male ratio was 9 : 1 and the mean age at presentation was 24.4 ± 10.4 years. Prevalence of manifestations included: musculoskeletal (83.2%), cutaneous (81.1%), renal (65.4%), neuropsychiatric (23.4%), pulmonary (21.5%), cardiac (17.2%), and hematologic (66.4%) symptoms. There was positive antinuclear antibodies in 86.4% and anti‐DNA in 82.3% of patients. Overlap syndrome and positive family history with other autoimmune diseases were detected in 7.6% and 3.4% of patients, respectively. Conclusion: In our patients the prevalence of cutaneous involvement was similar to those of nearby countries (with similar climate). Renal involvement was seen more than some other countries especially more than European countries, while other manifestations (such as hematologic and joint involvement) were similar to European countries (with similar ethnicity). We may conclude that genetic and/or climatic factors may lead to different presentations of lupus.  相似文献   
66.
Objective: To identify the clinical picture of Behcet’s disease in a large cohort of patients (6500) in Iran, over a period of 35 years, and compare them with other large series from around the world. Methods: Patients with Behcet’s disease from all over Iran were seen in the Behcet’s Disease Research Unit by a multidisciplinary team (rheumatologists, dermatologists, and ophthalmologists). Diagnosis was based on ‘expert opinion’. Data were collected on a standardized data sheet (105 items), and stored in an electronic database. Data were updated at each follow‐up. Results: Male to female ratio was 1.22 : 1.00. The mean age at onset was 26 years ± 11.3. The frequency of symptoms were: oral aphthosis 97.3%, genital aphthosis 64.6%, skin manifestations 64.9% (pseudofolliculitis 54.5%, erythema nodosum 22.5%, other lesions 7%), pathergy phenomenon 52.5%, ophthalmologic manifes‐tations 56.8% (anterior uveitis 41.2%, posterior uveitis 44.9%, retinal vasculitis 32.1%), joint manifestations 37.4% (arthralgia 17.2%, monoarticular arthritis 7.6%, oligoarthritis 16.8%, ankylosing spondylitis 2%), neurological manifestations 3.8% (central manifestations 3.5%, mononeuritis multiplex 0.3%), gastrointestinal manifestations 7.4%, vascular involvement 8.3% (phlebitis 5.7%, superficial phlebitis 2.2%, large vein thrombosis 1.1%, arterial thrombosis 0.154%, aneurysm 0.5%), epididymitis 4.7%, cardiac involvement 0.6%, and pulmonary involvement 0.9%. Sedimentation rate was normal in 46.5% of patients. Abnormal urine sediment was detected in 12.2%. HLA‐B5 was present in 53.3% and HLA‐B51 in 47.9% of patients. Conclusion: Behcet’s disease is mainly seen in young people. The most frequent symptoms are mucocutaneous, ocular and joint manifestations. Comparison with large series did not show major differences.  相似文献   
67.

Background  

Attitudes towards intimate partner violence against women (IPVAW) has been suggested as one of the prominent predictor of IPVAW. In this study, we take a step back from individual-level variables and examine relationship between societal-level measures and sex differences in attitudes towards IPVAW.  相似文献   
68.
Hepatitis B virus (HBV) continues to be a major cause of morbidity and mortality worldwide. It is estimated that about 350 million people throughout the world are chronically infected with HBV. Some of these people will develop hepatic cirrhosis with decompensation and/or hepatocellular carcinoma. For such patients, liver transplantation may be the only hope for cure or real improvement in quality and quantity of life. Formerly, due to rapidity of recurrence of HBV infection after liver transplantation, usually rapidly progressive, liver transplantation was considered to be contraindicated. This changed dramatically following the demonstration that hepatitis B immune globulin (HBIG), could prevent recurrent HBV infection. HBIG has been the standard of care for the past two decades or so. Recently, with the advent of highly active inhibitors of the ribose nucleic acid polymerase of HBV (entecavir, tenofovir), there has been growing evidence that HBIG needs to be given for shorter lengths of time; indeed, it may no longer be necessary at all. In this review, we describe genetic variants of HBV and past, present, and future prophylaxis of HBV infection during and after liver transplantation. We have reviewed the extant medical literature on the subject of infection with the HBV, placing particular emphasis upon the prevention and treatment of recurrent HBV during and after liver transplantation. For the review, we searched PubMed for all papers on the subject of “hepatitis B virus AND liver transplantation”. We describe some of the more clinically relevant and important genetic variations in the HBV. We also describe current practices at our medical centers, provide a summary and analysis of comparative costs for alternative strategies for prevention of recurrent HBV, and pose important still unanswered questions that are in need of answers during the next decade or two. We conclude that it is now rational and cost-effective to decrease and, perhaps, cease altogether, the routine use of HBIG during and following liver transplantation for HBV infection. Here we propose an individualized prophylaxis regimen, based on an integrated approach and risk-assessment.  相似文献   
69.

Purpose

To compare proteomic profiles of spermatozoa from patients with varicocele and poor sperm quality before and after varicocelectomy.

Methods

This work was designed as a prospective and observational study. The study was based on 20 men with varicocele grade 3 and poor sperm quality undergoing varicocelectomy at the Fertility Unit of Royan institute in 2009. Two semen samples were collected, one before varicocelectomy and the other after surgery. Protein separation was done by two-dimensional protein electrophoresis, and analyzed by gel densitometry and mass spectrometry. Differential sperm protein expression levels were measured by gel densitometry.

Results

Comparison of the sperm parameters showed that sperm motility and concentration were increased after varicocelectomy. At the level of protein, a total of 3 protein spots were identified whose expression was significantly lower in sperm samples before varicocelectomy compared with after surgery including heat shock protein A5 (HSPA5), superoxide dismutase 1 (SOD1) and δ-subunit of the catalytic core of mitochondrial adenosine triphosphate synthase (ATP5D).

Conclusions

High grade varicocoele affects sperm protein expression presumably because of increasing testicular temperature. These proteins play essential roles in sperm production, DNA integrity protection, and sperm motility. This novel study demonstrates that varicocelectomy can improve both sperm quality and proteins expression.  相似文献   
70.
Oral lichen planus (OLP) is an immune-related disorder with unknown exact etiology but established prevalencein females. There are six clinical forms of OLP, ranging from asymptomatic white keratotic lesions to painful erosionsand ulcerations. The aim of the present report is to overview pathologic and therapeutic aspects. Peroxidation products,antioxidants, cortisol, and immunoglobulins are potential biomarkers to predict OLP occurrence. The risk of OLPdevelopment in patients with hepatitis B and C infection is 2-fold greater than in healthy individuals, while there is nosignificant relation with diabetes mellitus. Corticosteroids are common drugs to treat OLP and their combination withother agents can be most effective. Folic acid and variants of vitamin B are also potential treatments since they targethematological abnormalities.  相似文献   
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