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51.
There is a great deal of indirect, nonexperimental evidence that a pattern of earlier-stage disease at diagnosis has a better outcome. Increased early detection activities can change, these stage patterns while various biases and the question of generalizability need to be kept in mind in their interpretation. The indirect evidences of possible benefit from early detection activities includes an increase in the number of cases detected, a pattern of more early- and less advanced-stage cases, an increase in the overall site-specific survival rate, and a decrease in the case fatality rate. Unless these intermediate markers are favorable, it is unlikely that early detection will reduce mortality. In addition, one should also differentiate a reduced incidence or a change in treatment as a cause for reduced mortality. 相似文献
52.
嗅神经母细胞瘤的临床病理及超微结构观察 总被引:2,自引:0,他引:2
本文报道了12例嗅神经母细胞瘤的临床病理及其中2例的超微结构特点。光镜观察结果,12例均可见细胞之间由细胞突起形成的嗜酸性背景,有4例可见Flexner菊形团、7例见Homer-Wright菊形团(其中3例同时存在Flexner菊形团);电镜观察结果,细胞具有轴突样和树突样突起,胞体及突起内含微管、神经细丝及神经分泌颗粒,细胞突起之间见突触样的连接。作者并对该瘤的诊断问题进行了探讨。 相似文献
53.
The role of various subfamilies of rat hepatic cytochrome P450 in the oxidation of ethosuximide was evaluated by comparing ethosuximide clearance in control rats and those pretreated with relatively selective P450 inducers and/or inhibitors. Clotrimazole pretreatment increased ethosuximide clearance threefold (p less than 0.005). Dexamethasone increased ethosuximide clearance twofold (p less than 0.001), and the dexamethasone effect was completely abolished by a single dose of triacetyloleandomycin. These results suggest a prominent role for cytochrome P450IIIA in ethosuximide metabolism in the rat. Isoniazid increased ethosuximide clearance twofold (p less than 0.001), and this effect was abolished by a single dose of diallylsulfide, suggesting that ethosuximide is also processed by cytochrome P450IIE1 in rats. Phenobarbital pretreatment increased ethosuximide clearance 2-2.7 fold (p less than 0.001); an effect that was only partially reversed by orphenadrine, an inhibitor of cytochrome P450IIB/IIC enzymes. This suggests a quantitatively less important role for the IIB/IIC subfamilies in processing ethosuximide, since phenobarbital is an inducer of P450 subfamilies IIB, IIC, IIE, and IIIA. Neither the cytochrome P450IA inducer, beta-naphthoflavone, nor the inhibitor, alpha-naphthoflavone altered ethosuximide clearance. Ajmaline, an inhibitor of cytochrome P450IID, had no effect on ethosuximide clearance. Together, these findings suggest that ethosuximide is principally oxidized by cytochrome P450IIIA, and that cytochrome P450IIE may play an important role. Cytochromes P450IIB/C play less prominent roles in ethosuximide oxidation, and neither cytochrome P450IA nor cytochrome P450IID is involved. 相似文献
54.
I Chu D C Villeneuve V E Secours R Otson V E Valli 《Journal of toxicology and environmental health》1991,33(3):317-326
The present study was conducted to determine the dermal toxicity of coal coprocessing products and to assess their potential health hazards. Groups of 10 male and 10 female Sprague-Dawley rats were administered dermally coal coprocessing products (light gas oil, LGO; heavy gas oil I, HGOI; heavy gas oil II, HGOII) at 1 g/kg body weight/d for 14 d. The control and positive control groups received normal saline and a coal liquefaction product (CLP) at the same dose level, respectively. Treatment with either the three fractions of coprocessing products or CLP caused decreased growth rate and food consumption in animals of both sexes. Liver enlargement occurred in groups treated with HGOI, HGOII, and CLP. Decreased serum glucose was observed in animals of both sexes treated with the three fractions and CLP. Treatment with HGOI and CLP caused an elevation of hepatic microsomal ethoxyresorufin deethylase activity in the rat of both sexes. The three fractions and CLP caused mild anemia. Mild treatment-related histological changes were observed in the liver, spleen, thyroid, bone marrow, and kidney. All three fractions of coprocessing products were tested for their mutagenicity in five strains of Salmonella typhimurium: TA98, TA100, TA1535, TA1537, and TA1538. HGOI, after metabolic activation, was found to be mutagenic in the strains of TA98, TA100, and TA1538. In contrast, HGOII was mutagenic in the five strains with or without metabolic activation. These data indicate that HGOI and HGOII are more toxic than LGO, and should be subjected to further studies to determine their long-term effects. 相似文献
55.
本文报告了经手术病理证实的53例甲状腺肿瘤,均作了甲状腺造影和B超检查.通过比较分析,我们认为造影对确定肿瘤的良、恶性以及延伸到胸骨后的异位甲状腺肿瘤有其优越性,是一项有效的检查方法;超声则能准确地判断肿瘤的囊、实性,适合碘过敏患者的检查.两种检查各有特点,配合使用有利于对甲状腺肿瘤的诊断和治疗. 相似文献
56.
Jen Te Hsu Chi Ming Chu Shih Tai Chang Hui Wen Cheng Nye Jan Cheng Wan-Ching Ho Chang Min Chung 《Circulation journal》2006,70(12):1611-1616
BACKGROUND: This study investigated the utility of the alveolar - arterial oxygen pressure difference (AaDO (2)) in predicting the short-term prognosis of acute pulmonary embolism (PE). METHODS AND RESULTS: This study retrospectively enrolled 114 consecutive patients with acute PE, diagnosed by either spiral computed tomography or high probability ventilation - perfusion lung scans. During the first 24 h of admission, all patients had initial artery blood gas collected under room air. Patient exclusion criteria were chronic lung disease, septic emboli, and moderate and low probability lung scans. Patients were assigned to 2 groups based on either 30-day death or a 30-day composite event. Receiver operating characteristic analyses was used to determine the AaDO(2) cut-off value for predicting primary and composite endpoints. Statistical analysis demonstrated significant differences in AaDO(2) between the 30-day composite endpoint group and the 30-day composite event-free survival group (p=0.012). The AaDO(2) had a strong trend between the 30-day death group and the survival group (p=0.062). The best cut-off value for AaDO(2) was 53 mmHg and using this, the positive predictive value for 30-day death was 25% and the negative predictive value was 92%. For the 30-day composite endpoint, the positive predictive value for AaDO(2) was 35%, and the negative predictive value was 84%. In this study, thrombocytopenia was also an indicator of poor prognosis for patients with acute PE. CONCLUSION: The AaDO(2) measurement is a highly useful and simple measurement for predicting short-term prognosis in patients with acute PE. It has high negative predictive value and moderate positive predictive value for 30-day death and 30-day composite event. Aggressive thrombolytic treatment strategies should be considered for patients with an initial poor prognostic parameter (ie, AaDO(2) >or=53 mmHg). 相似文献
57.
兔膀胱出口部分梗阻所致逼尿肌超微结构的改变 总被引:4,自引:0,他引:4
目的 观察兔膀胱出口部分梗阻后逼尿肌细胞超微结构的改变。 方法 建立雄性兔膀胱出口部分梗阻动物模型 ,利用透射电镜观察其逼尿肌细胞内超微结构 ,应用ImagineTool图像分析软件检测粗面内质网面积和线粒体密度。 结果 梗阻组逼尿肌细胞内单位面积平均 1 1 5 .2 8μm2 ,胞质中粗面内质网面积 (5 .377± 2 .31 8) μm2 ,较对照组的 (0 .476± 0 .31 9) μm2 明显扩大 ;线粒体相对密度为 1 .0 2 7± 0 .0 64 ,较对照组的 0 .830± 0 .0 58明显下降 ,P均 <0 .0 1。 结论 膀胱出口部分梗阻后逼尿肌细胞内质网扩张 ,提示其合成蛋白质功能增强 ,从而引起膀胱壁增厚 ;而线粒体水肿明显 ,密度下降 ,提示逼尿肌细胞能量代谢障碍 ,导致其收缩功能下降 相似文献
58.
目的 探讨计算机体层成像多平面重建(CTMPR)在评价椎间融合中的作用,寻找定量评价椎间融合的新方法.方法 13例行腰椎间融合的患者术后1周、3个月、6个月行CTMPR,行椎间融合器(Cage)内植骨CT值定量测量.结果 术后1周Cage内植骨CT值为(619.52±26.97)Hu,术后3个月为(628.69±42.60)Hu,术后6个月为(657.77±37.43)Hu.术后1周与术后3个月相比无显著性差异,与术后6个月相比有显著性差异.结论 CT值的测量在椎间融合的判断中具有高准确性. 相似文献
59.
一日,我接到一位女土的咨询电话,她希望我能解释一下为什么每次过性生活时,丈夫射精她没有感觉.这是一个有关提高夫妻性爱质量的问题. 一般来说,夫妻在做爱过程中,丈夫射精妻子都会有所感觉.要么妻子感到丈夫急促的喘气声,身体激烈地晃动,小腹有紧张感;要么妻子感到阴道中有一股液体暖流;要么妻子的阴道口出现收缩感,随之带来快感乃至达到性高潮妻子在丈夫射精时没感觉,一般表现为以下几种情况. 相似文献
60.
C-Y Chu 《Journal of the European Academy of Dermatology and Venereology》2007,21(4):484-490
BACKGROUND: Steroid-induced rosacea-like eruption is characterized by facial rosacea-like dermatitis in patients that have been treated with topical steroids for relatively long periods. OBJECTIVE: To evaluate the efficacy and tolerability of 1% pimecrolimus topical cream for steroid-induced rosacea-like eruption. METHODS: In an open-label pilot study, 40 patients were enrolled and instructed to apply 1% pimecrolimus cream twice daily for 6 weeks. Patients were evaluated by a rosacea clinical score, investigator's global assessment, overall erythema severity, and tolerability at weeks 0, 2, and 6. RESULTS: In 35 patients, the rosacea clinical score decreased significantly from 16.0+/-4.3 at baseline to 8.1+/-3.3 at week 2 and 4.2+/-2.5 at week 6 (P<0.0001). Investigator's global assessment was 4.1+/-1.1 (baseline), then decreased to 1.4+/-0.8 (week 2) and 0.5+/-0.6 (week 6) (P<0.0001). By week 6, 48.6% of the patients were clear. Overall erythema severity was 2.4+/-0.7 (baseline), 0.9+/-0.4 (week 2), and 0.3+/-0.4 (week 6) (P<0.0001). Cutaneous adverse events (local burning, stinging, and itching) occurred in 17.5%. CONCLUSION: Pimecrolimus cream might be efficacious, safe, and well tolerated for steroid-induced rosacea-like eruption. The small sample size and open label nature of this study is its limitation. Further double-blind, vehicle-controlled studies are needed. 相似文献