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ObjectivesTo compare the effect of use of laser, casein phosphopeptide–amorphous calcium phosphate (CPP–ACP), and their combination on prevention of enamel demineralization using polarized light microscopy to assess lesion depth.Materials and MethodsEighty premolars were randomly allocated to four equal groups (n = 20): Group I: Control group, no preventive measures. Group II: CPP–ACP. Group III: Er,Cr:YSGG laser. Group IV: Er,Cr:YSGG laser followed by CPP–ACP. Specimens were subjected to thermocycling and brushing protocols equivalent to 1 year intraorally. Then, all teeth were subjected to acid challenge. Teeth were then sectioned longitudinally and examined under a polarized light microscope and lesion depth was measured.ResultsGroup IV resulted in the least lesion depth with a significant difference between it and all other groups. CPP–ACP alone and laser alone also showed a significant difference in white spot lesion (WSL) depth compared to the control group; however, no significant difference was found between them.ConclusionsThe combined use of laser and CPP–ACP showed the best prevention against WSL development. The use of CPP–ACP or laser alone also resulted in a significant reduction in lesion depth but was significantly less than their combined use, with no significant difference between them.  相似文献   
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OBJECTIVES: In this study, we sought the proper cutoff level for quantitative ultrasonography (QUS) of the heel in identifying bone mineral density (BMD) categories as determined by dual-energy x-ray absorptiometry (DXA) in postmenopausal women. METHODS: With the use of DXA, BMD categories of the lumbar spine and different areas of the left femur of 420 healthy women according to World Health Organization definitions were determined. Quantitative ultrasonography of the heel was also performed in each subject. Receiver operating characteristic curves were plotted, and sensitivity and specificity of QUS to diagnose osteoporosis were examined at different points to identify the best cutoff level. The diagnostic agreement between the two techniques in identifying osteoporosis was assessed with kappa scores. RESULTS: The kappa scores were 0.31 for the lumbar region and 0.5 for the femoral neck region. On the receiver operating characteristic study, a score of -1 was found to be the appropriate cutoff point for QUS studies, in which the sensitivity of QUS to diagnose BMD osteoporosis varied between 78% and 87.5% depending on the site of the DXA study. With the proposed cutoff point (-1), sensitivity and specificity of QUS in detecting osteoporosis at the lumbar spine were 83.9% and 51%, respectively, and at the femoral neck were 84% and 50%, respectively. CONCLUSIONS: Insufficient agreement between QUS and DXA led to uncertainty on expected BMD in people tested by QUS. The proposed cutoff value could achieve higher sensitivity but only by accepting higher rates of false-positive results.  相似文献   
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Clinical features of systemic lupus erythematosus (SLE) have been described from different geographical regions in the world. However, data from many Middle East countries, including Iran, are scarce. This study aims to demonstrate the demographic, clinical, and laboratory characteristics in Iranian patients with SLE. In this prospective study, all the patients referring to Shiraz educational hospitals (Nemazi-Hafez) with SLE (American College of Rheumatology criteria) during a 5-year period (2001 to 2006) were included. A complete history was taken; physical examination and routine hematological, serological, and immunological tests were done for each patient. There were 356 women and 54 men with an average age of 30.27 years at the onset of disease. Of the patients, 78% had hematological abnormalities, 65.5% had articular involvement, 54.5% had photosensitivity, and 60.5% had malar rash. Serositis occurred in 38% of patients of whom 12% had pericarditis and 26% had pleuritis. Nephritis was diagnosed in 48% of the cases and consisted always of glomerular nephritis. Biopsy-proven lupus nephritis was in most cases class IV(49.7% of all the biopsies). Oral ulcers were observed in 28% of patients. Neuropsychiatric manifestations, gastrointestinal involvement, and lymphadenopathy were observed in 31.5%, 8.3%, and 14.2% of patients, respectively. In all, 93% of patients were positive for antinuclear antibodies, whereas antidouble-stranded DNA was positive in 83% of patients. Coomb's positive hemolytic anemia appeared in 12.4% of the cases. Rheumatoid factor was detected in 9.7% of patients, and lupus erythematosus cell was seen in 32.5% of them. In all, 196 (47.8%) patients represented hypocomplementemia. Regarding hematological manifestations, 74.5% had microcytic hypochromic anemia, 64.6% had leukopenia, and 44.6% had thrombocytopenia; 18 (4.4%) patients died during the study period of which eight (2%) died because of cardiopulmonary involvement. Generally, there was more cutaneous, serositis, and neuropsychiatric involvement in our population than other Middle East countries. Serositis was associated with poorer prognosis, and the pattern of disease in these patients was much more sever than patients without serositis (P = 0.001). This is the first study of its kind in Iran. More multicenter studies should be undertaken in Iran to describe the pattern of SLE.  相似文献   
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Background: Selenium, like other trace elements and antioxidant enzymes, is known as an antioxidant and immunomodulator trace element. Due to recent evidence for selenium deficiency in Behcet’s syndrome, this study is to evaluate the correlation of serum selenium level with Behcet’s disease (BD). Materials: This case–control study was conducted on 46 BD patients and 46 healthy controls in a rheumatology research centre. The case and control groups were both age‐ and race‐matched. Serum selenium level was then measured by atomic absorption spectrometry Shimadzu AA‐680. Average serum levels of both groups were then compared and analyzed using t‐test. Results: Mean serum selenium levels of patients appeared to be 66.4 ± 15.38 μg/L which was significantly lower than that in the healthy controls (86.87 ± 17.18 μg/L) (P < 0.005). Taking physician global assessment of disease activity into account, significant difference was detected between the patients with active disease (66.57 ± 15.21 μg/L) and those in the inactive state (65.83 ± 14.75 μg/L). Regardless of the findings mentioned above, serum selenium level was meaningfully elevated among the patients with ocular involvement (P < 0.001). Conclusions: These findings demonstrated that selenium serum level among BD patients was lower than that in healthy controls, whereas among the patients with ocular involvement it was higher than those not involved.  相似文献   
57.
Purpose: To describe the clinical experience with retinal vasculitis at 4 Egyptian tertiary eye centers.

Methods: A multicenter retrospective chart review of all patients with retinal vasculitis encountered at 4 ocular inflammation referral clinics in Egypt between February 2013 and February 2018.

Results: The study included 618 patients (327 males and 291 females). Of these, 284 patients had isolated retinal vasculitis, whereas 233 patients had an associated systemic inflammatory disease, the most frequent being Behçet’s disease, followed by sarcoidosis. In 101 patients, retinal vasculitis could be attributed to an infectious etiology, and among this category, the most common was tuberculosis, followed by toxoplasmosis.

Conclusion: In our Egyptian cohort, more than half the patients had their retinal vasculitis as part of a serious systemic disease, or as part of an infectious process, as tuberculosis. And in view of the significant potential morbidity of these conditions, the local ophthalmologists need to be aware of these entities when faced with patients presenting with retinal vasculitis.  相似文献   
58.
Picropodophyllin (PPP) is an anticancer drug undergoing clinical development in NSCLC. PPP has been shown to suppress IGF-1R signaling and to induce a G2/M cell cycle phase arrest but the exact mechanisms remain to be elucidated.The present study identified an IGF-1-independent mechanism of PPP leading to pro-metaphase arrest. The mitotic block was induced in human cancer cell lines and in an A549 xenograft mouse but did not occur in normal hepatocytes/mouse tissues.Cell cycle arrest by PPP occurred in vitro and in vivo accompanied by prominent CDK1 activation, and was IGF-1R-independent since it occurred also in IGF-1R-depleted and null cells. The tumor cells were not arrested in G2/M but in mitosis. Centrosome separation was prevented during mitotic entry, resulting in a monopolar mitotic spindle with subsequent prometaphase-arrest, independent of Plk1/Aurora A or Eg5, and leading to cell features of mitotic catastrophe. PPP also increased soluble tubulin and decreased spindle-associated tubulin within minutes, indicating that it interfered with microtubule dynamics.These results provide a novel IGF-1R-independent mechanism of antitumor effects of PPP.  相似文献   
59.
The repair and management of full-thickness skin defects resulting from burns and chronic wounds remain a significant unmet clinical challenge. For those skin defects exceeding 50%-60% of total body surface area, it is impractical to treat with autologous skin transplants because of the shortage of donor sites. The possibility of using tissue-engineered skin grafts for full-thickness wound repair is a promising approach. The primary goal of tissue-engineered skin grafts is to restore lost barrier function, but regeneration of appendages, such as hair follicles, has to be yet achieved. The successful regeneration of hair follicles in immunodeficient mice suggests that creating human hair follicles in tissue-engineered skin grafts is feasible. However, many limitations still need to be explored, particularly enriching isolated cells with trichogenic capacity, maintaining this ability during processing, and providing the cells with proper environmental cues. Current advances in hair follicle regeneration, in vitro and in vivo, are concisely summarized in this report, and key requirements to bioengineer a hair follicle are proposed, with emphasis on a three-dimensional approach.  相似文献   
60.

Background

Radiology plays an important role in evaluation of a trauma patient. Although chest radiography is recommended for initial evaluation of the trauma patient by the Advanced Trauma Life Support course, we hypothesized that precise physical examinations and history taking accurately identify those blunt trauma patients at low risk for chest injury, making routine radiographs unnecessary. Thus, this study was performed to investigate the role of chest radiography in initial evaluation of those trauma patients with normal physical examination.

Methods

In this prospective cross-sectional study, all the hemodynamically stable blunt trauma patients with negative physical examination result referred to our trauma center during a 4-month period (March-June 2009) were included. Chest radiographies were performed and reviewed for abnormalities.

Results

During the study period, 5091 blunt trauma patients referred to our center, out of which, 1008 were hemodynamically stable and had negative physical examination result. Only 1 (0.1%) patient had abnormal chest radiography that showed perihilar lymphadenopathy, unrelated to trauma.

Conclusion

Performing routine chest radiography in stable blunt trauma patients is of low clinical value. Thus, decision making for performing chest radiography in blunt trauma patients based on clinical findings would be efficacious and resource saving.  相似文献   
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