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51.
Oxidative stress is an important factor for aging. The antioxidative enzymes glutathione peroxidase (GPx), glutathione reductase (GRd) and superoxide dismutase (SOD) play a crucial role protecting the organism against the age-dependent oxidative stress. Glutathione (GSH) is present in nearly all living cells. GSH is one of the main antioxidants in the cell and it serves several physiological functions. Our purpose was to evaluate the age-related changes in mitochondrial GPx, GRd and SOD activities, and mitochondrial GSH pool in the brains of young (3months) and aged rats (24months). We also investigated whether melatonin administration influences these brain mitochondrial enzyme activities and GSH levels in young and aged rats. The results showed that GPx activity increased with age, whereas melatonin treatment decreased GPx activity in the aged rats at levels similar to those in young and young+melatonin groups. The activities of GRd and SOD, however, did not change with age. But, melatonin treatment increased SOD activity in the aged rats. GSH levels, which also increased with age, were not modified by melatonin treatment. The reduction in the SOD/GPx and GR/GPx ratios with age was prevented by melatonin administration. Together, our results suggest that the age-related oxidative stress in rat brain mitochondria is more apparent when the antioxidant enzyme ratios are analyzed instead of their absolute values. The antioxidative effects of melatonin were also supported by the recovery of the enzyme ratios during aging.  相似文献   
52.
An 83‐year‐old male patient presented to the outpatient clinic with complaint of swelling at right antecubital area. Ultrasonographic examination of the right upper extremity revealed a mass lesion within the right cephalic vein, which was consistent with thrombus. A computed tomography (CT) venography showed contrast enhancement in cephalic vein at distal arm and an aneurysmatic thrombus area displaying regular borders with a size of 28*30 mm; there was no contrast enhancement at more proximal levels at the cephalic vein.  相似文献   
53.
Celiac disease (CD) is a disease having the characteristic pathology of the mucosa of the small intestine. The prevalence of CD in the Turkish population has not been investigated previously. The present study was designed to determine the prevalence of CD in healthy blood donors. Serum samples of 2000 healthy blood donors presenting to Hacettepe University Faculty of Medicine Hospital Blood Bank were tested for tissue transglutaminase (tTG) IgA and IgG antibodies with enzyme-linked immunosorbent assay (ELISA; Euroimmune, Germany). The histopathological findings for the cases with positive serology were evaluated. The distribution of sex was 95.7% male, and 4.3% female. The mean age was 33 +/- 9. Among 2000 donors, 23 (1.15%) were positive for tTG IgA antibody and 3 (0.15%) were positive for tTG IgG antibody. None of the samples was positive for both antibodies. Serum total IgA was measured in two cases with only tTG IgG positivity and was found to be low in one case. Twelve subjects positive for tTG agreed to endoscopy and biopsy. Histopathological examination revealed changes classified as Marsh III-II in one, Marsh II in two, Marsh I in seven, and Marsh 0 in two donors. This was the first study conducted to determine the prevalence of tTG positivity in the Turkish population. The tTG antibody positivity prevalence in healthy blood donors was as high as 1.3%. This study shows that the prevalence of CD in the Turkish population is relatively high in comparison to that in the Western world.  相似文献   
54.
A 56 year old patient who developed acute pancreatitis following intrabiliary rupture of a hydatic cyst of the liver is reported herein. Hepatic hydatic disease is a very rare cause of acute pancreatitis for which the surgical treatment consists of evacuation of the cyst material and biliary drainage. Cystoenteric drainage is not mandatory.  相似文献   
55.
Guided tissue regeneration is based on preventing the more rapidly proliferating epithelium from growing into the periodontal defect after surgical procedures incorporating barrier membranes. The aim of this study was to compare the proliferative activity of gingival epithelium using proliferating cell nuclear antigen (PCNA) as a marker of cell proliferation after surgical treatments with bioactive glass graft material and bioabsorbable membrane. Using split mouth design, 20 intrabony defects were randomly assigned treatments with bioactive glass (BG group) or bioabsorbable membrane (BM group). Gingival biopsies were taken at preoperative and postoperative 12 weeks. After histological processing, the number of the inflammatory cells was measured in hematoxylin and eosin-stained sections; PCNA expression was determined in immunohistochemically-stained sections. At postoperative 12 weeks, the number of the inflammatory cells was significantly decreased (p < 0.01), PCNA expression was significantly increased (p < 0.001) in both treatment groups compared to baseline data. There was no significant difference in PCNA expression between baseline values of two groups (p > 0.05), while at postoperative 12 weeks, increase in BG group was significantly greater than that in BM group (p < 0.001). These results suggest that epithelial cell proliferation is more prominent after treatment of intrabony defects with bioactive glass compared to the treatment with bioabsorbable membrane.  相似文献   
56.
OBJECTIVE: In recent years, platelet-rich plasma combined with graft materials has been used for periodontal regeneration. The individual role of blood products with guided tissue regeneration in periodontal regenerative therapy is unclear and needs to be elucidated. The purpose of this study was to compare the clinical and radiological effectiveness of platelet pellet/guided tissue regeneration (PP/GTR) and bioactive glass/GTR (BG/GTR) treatments in patients with periodontal disease. MATERIAL AND METHODS: Using a split mouth design, 15 chronic periodontitis patients with pocket depths > or = 6 mm following periodontal initial therapy were randomly assigned to treatment with a combination of PP/GTR or BG/GTR in contralateral dentition areas. An absorbable membrane of polylactic acid was used GTR. The criteria for the comparative study were preoperative and postoperative 6 months pocket depth, clinical attachment level, and radiological alveolar bone level. RESULTS: Both treatment modalities resulted in significant pocket depth reduction and gain in clinical attachment and alveolar bone level compared to the preoperative values (p < 0.01). Reduction in pocket depth, gain in clinical attachment and alveolar bone level were 4(3-6), 4.1+/-0.7, 4.9+/-1.4 mm in the PP/GTR group and 4(3-7), 4.1+/-1.2, 5.9+/-1.7 mm in the BG/GTR group, respectively. The differences between the two groups were not statistically significant (p > 0.05). CONCLUSIONS: Within the limits of this study, it was concluded that PP may be effective as a bioactive glass graft material and used as a graft material for treating intrabony defects. PP thus appears to be a suitable alternative in the regenerative treatment of intrabony periodontal defects.  相似文献   
57.
The histopathological effects of cholesterol and the protective effects of vitamin E and selenium (Se) on renal histology were examined in Sprague-Dawley rats. Light-microscopic evaluation of the renal cortex revealed: glomerular fibrosis, cellular and mesangial proliferation, capillary obliteration and cholesterol crystals in the tubular lumina of the cholesterol-fed group. These results suggest that oxidated LDL (O-LDL) is a cytotoxic factor which stimulates mesangial cell and matrix proliferation. Ultrastructurally, small and large lipid vacuolization in intracapillary lumina, adhesion of epithelial foot processes, mesangial foam cells and polymorphonuclear leukocytes were seen in the cholesterol-fed group. In the groups fed cholesterol + vitamin E, cholesterol + Se and cholesterol + vitamin E + Se, morphological improvements were observed. It appeared that an excess in O-LDL, reactive oxygen species and growth factors might play an important role in the pathogenesis of glomerulosclerosis. In addition, it was concluded that antioxidant therapy may prevent LDL oxidation and generation of free radicals.  相似文献   
58.
PURPOSEThis study evaluated single-center results of endovascular treatment in renal angiomyolipoma (AML) to determine whether there is clinical relevance of adding proximal coil embolization to distal particle embolization in terms of safety, efficacy, and retreatment rates.METHODSA retrospective analysis was performed to evaluate patients undergoing transarterial embolization for renal AMLs from January 2007 to October 2020. Parameters regarding patient and tumor characteristics, embolization technique, treatment outcome, and complications were recorded. Patients were divided into 2 groups as A (only particle group) and B (particle + coil group) based on the type of embolic agent used for treatment. Comparative analysis was performed between the 2 groups in terms of tumor size reduction, retreatment, and complication rates. RESULTSIn this study, 42 patients (37 (88.1%) females and 5 (11.9%) males) harboring 48 AMLs were included. The mean age was 43.46 (range, 20-78). The technical success rate was 95.8% (46 of 48 procedures). The mean size reduction was 1.94 ± 1 cm (P  < .001) after treatments; however, no significant difference was seen between groups in terms of tumor size reduction. Retreatment rates were 3.1% (1 of 32 cases) in group A and 14.3% (2 of 14 cases) in group B (P  = .21). No significant difference was found between groups in terms of bleeding and complication rates during the perioperative period. Mean follow-up duration was 26.48 ± 25.71 (range, 2-102) months.CONCLUSIONIn this study, no clear supplementary benefit was observed in terms of safety and efficacy with the adjunction of coils to distal particle embolization in the management of AMLs.

Main points
  • Transarterial embolization is safe and effective in reducing lesion size and bleeding rates in the management of angiomyolipomas.
  • Lesion size reduction can be achieved with both techniques; solely microparticle embolization or distal microparticle embolization plus proximal coil embolization.
  • Proximal coil embolization does not provide an additional benefit with lesions having intratumoral microaneurysms ≥5 mm as the study showed no difference in complication and bleeding rates.
Renal angiomyolipoma (AML) is one of the most common benign tumors of the kidney, with an incidence of 0.4% in the general population.1,2 AMLs are seen in 2 forms; sporadic and tuberosclerosis (TSC) related. Sporadic form accounts for 80% of the AML cases. TSC-related AMLs tend to be bilateral, multifocal, larger with a faster growth rate and are more symptomatic than the sporadic type.3 AMLs have slow growth rates and rarely necessitate invasive treatment at all times.4 Historical data suggest that AMLs equal to or larger than 4 cm and those that have 5 mm or larger microaneurysms tend to be more symptomatic and prone to hemorrhage.5,6 Although a treatment indication based on tumor size larger than 4 cm is subject to dispute,7 treatment decisions are often made using these cut-off values in the literature. Treatment options consist of medical treatment, surgery, transarterial embolization (TAE), and thermal ablation with no definitive recommendation on the first-line treatment choice.8,9 However, because of its less-invasive nature, TAE is a favored choice in the management of AMLs over surgery. So far, various embolic agents (ethanol, microparticles, coils, gel foam, etc.) have been used in the management of patients with AML.10 Concerning the embolic materials, Patatas et al.11 compared solely coil embolization with solely microparticle embolization in transarterial embolization of AMLs. They found similar reduction rates on computed tomography (CT) follow-up between the 2 groups. Ewalt et al.12 showed that microparticle plus coil embolization is effective in terms of size reduction in large (>4 cm) and symptomatic and TSC-related AMLs. Although based on the literature, coils, microparticles, and microparticle + coil embolization are all safe and efficient, there are no clear data on the additional benefit of adding coil embolization to microparticle embolization in terms of treatment efficacy. Therefore, this study aimed to evaluate within single-center results whether there is clinical relevance of adding proximal coil embolization to distal microparticle embolization in terms of safety, efficacy, and retreatment rates.  相似文献   
59.
The hypothesis, a relationship between gingival tissue platelet activating factor (PAF) levels and healing after periodontal surgery, was tested by measuring PAF levels in gingival tissues collected from sites that had undergone flap surgery and guided tissue regeneration (GTR) or flap surgery alone. Using a split-mouth design, 20 intrabony defects were randomly assigned to treatment with flap surgery and GTR (group 1) or with flap surgery alone (group 2). Gingival tissue samples were obtained at surgery (baseline) and at 6-month follow-up evaluation visit. One half of each sample was used for analysis of PAF levels by high-performance liquid chromatography, and the other half of the sample was used for histomorphometric analysis that included measurements of number and diameter of blood vessels. PAF levels and diameter of blood vessels were significantly decreased (p < 0.01), and the number of blood vessels was significantly increased (p < 0.05) in both groups after 6 months compared to the baseline values. Postoperative number of blood vessels were significantly higher in group 1 (p < 0.05), whereas there was no significant difference in postoperative PAF levels between the two groups (p > 0.05). Based on the reported results, it is suggested that a decrease in gingival PAF levels might be found after conventional and regenerative periodontal surgery.  相似文献   
60.
The size of the final macular scar in subretinal neovascularisation (SRNV) is one of the most important determinants of final visual function in patients with subfoveal disease. We studied patients with bilateral macular scars from age-related subretinal neovascular membranes retrospectively in order to determine whether or not fellow eyes behave similarly. We found a significant correlation between eyes in terms of final scar size (r = 0.50, p less than 0.01). We found that 50% of fellow eyes with large macular scars (greater than 3 x 10(6) microns2) had similar sized lesions, while only 16% of fellow eyes with small macular scars (less than 0.5 x 10(6) microns2) had large scars (p less than 0.01). We discuss the significance of these findings in relation to the pathogenesis of subretinal neovascular membranes, and their implications for treatment.  相似文献   
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