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71.
Heike  A.  Bischoff-Ferrari  Waiter  C.  Willett  John  B.  Wong  苗峥 《美国医学会杂志》2006,25(4):248-248
背景:对于脊椎以外的骨折而言,补充口服维生素D的预防作用和用量仍无定论。 目的:评估补充维生素D在预防老年髋骨骨折和非脊椎骨折方面的效果。 数据来源:使用MEDLINE、Cochrance对照试验记录(1960~2005年)以及EMBASE(1991-2005年),对英文和非英文文章进行系统回顾。通过与临床专家接触,通过检索美国社会骨和骨矿研究协会提供的参考文献和摘要(1995~2004年).进一步寻找更多的研究。检索词包括随机对照试验(randomized controlled trial,RCT)、临床对照试验、随机分配、双盲法、维生素D3、维生素D2;25-羟基维生素D、骨折、人类、老年、摔倒和骨密度。 研究选取:纳入的研究仅限于口服补充维生素D(维生素D3、维生素D2、补钙或不补钙)与补钙或安慰剂比较的双盲RCTs。试验于检查髋部骨折或非脊椎骨折的老年人(年龄≥60岁)中进行。数据提取:两位作者根据预先规定独立提取相关数据,其中包括研究质量指标。 数据综合:所有的汇总分析均以随机效应模型为基础。5项有关髋部骨折的RCTs(n=9294)和7项有关非脊椎骨折危险的RCTs(n=9820)符合我们的纳入标准。所有试验均使用了维生素D3。对髋部和非脊椎骨折预防研究的异质性亦进行观察,用低剂量(400IU/d)和高剂量(700~800IU/d)分别合并RCTs后异质性消失。与补钙或安慰剂相比,每天服700~800IU的维生素D可使髋部骨折的相对危险(relative risk,aa)下降26%(3项RCTs共计5572人;RR,0.74;95%可信区间[confidence interval,CI],0.61~0.88),使非脊椎骨折的相对危险下降23%(5项RCTs共计6098人;RR,0.77;95%CI,0.68~0.87)。每天服400IU的维生素D(2项RCTs共计3722人;髋部骨折RR,1.15;95%CI,0.88~1.50;非脊椎骨折RR,1.03;95%CI,0.86—1.24)未见明显获益。 结论:口服补充维生素D(700~800IU/d)可以降低尚能活动的老人或慈善机构收容的老年人发生髋部骨折和脊椎以外骨折的危险,每天口服400IU维生素D并不足以预防骨折。  相似文献   
72.
Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
73.
背景:浴光疗同步治疗银屑病的有效性与UVB和死海盐的多靶点作用有关,同步治疗能够起到协同功效。目的:本回顾性研究的目的:①评价浴光疗同步治疗各种临床类型银屑病的有效性;②观察治疗反应有无不同;③获得更多数据以预测对不同类型银屑病的治疗效果,以便针对患者的类型选择治疗效果良好的方法。方法:根据Regensburg计划,患者接受了一个包括35次治疗的基础同步浴光疗疗程,随后又接受了一个包括25次治疗的维持治疗疗程。治疗中每周进行PASI评分以评价患者的皮肤状态。对373例按计划完成基础疗程的患者和其中78例完成维持疗程的患者的治疗…  相似文献   
74.
AIM: To evaluate whether the introduction of a strict protocol approach based on the systemic evaluation of critically ill pregnant women with complications of abortion affected outcome. SETTING: Indigent South Africans managed in the regional and tertiary hospitals of the Pretoria Academic Complex. METHOD: Since 1997 a standard definition of severe acute maternal morbidity (SAMM) has been used in the Pretoria Academic Complex. All cases of SAMM and maternal deaths were entered on the Maternal Morbidity and Mortality Audit System programme. A comparison of outcome of severely ill women who had complications of abortion was made between 1997-1998 (original protocol) and 2002-2004 (strict protocol). OUTCOME MEASURES: The mortality index and prevalence of organ system failure or dysfunction. RESULTS: In 1997-1998 there were 43 women with SAMM who survived and a further 10 maternal deaths due to complications of abortion, compared with 107 women with SAMM and 7 maternal deaths during 2002-2004. The mortality index declined from 18.9% in 1997-1998 to 6.1% in 2002-2004 (p = 0.02, odds ratio 0.28, 95% confidence limits 0.10 - 0.79). Significantly more women had hypovolaemic shock in 2002-2004 compared with 1997-1998 (54.4% v. 35.8%, p = 0.04), but fewer women had immune system failure including septic shock (18.4% v. 47.2%, p = 0.0002) and metabolic dysfunction (0 v. 5.7%, p = 0.03) and there was a trend to less renal failure (10.5% v. 22.6%, p = 0.06) and cardiac failure (4.4% v. 13.2%, p = 0.08). CONCLUSION: The strict protocol approach based on systemic evaluation in managing critically ill pregnant women with complications of abortion, coupled with an intensive, regular feedback mechanism, has been associated with a reduction in the mortality index.  相似文献   
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77.
OBJECTIVES: The aim of this study is to evaluate the effect of ZnSO(4) addition to a conventional glass ionomer and a resin-modified glass ionomer on solubility, flexural strength, zinc and fluoride (F) release, and Streptococcus mutans growth inhibition. METHODS: 5 or 10% ZnSO(4) was added to Vitremer and Ketac-Fil powders. Solubility test was performed based on ISO 7489. Flexural strength was determined by 3-point bending test based on ISO 4049. Zn release/uptake was determined by atomic emission spectrometry; F release/uptake was measured using a F-specific electrode. Both release measurements were performed for 15 d before and 15 d after recharging. Antibacterial test was conducted according to agar plate methods against S. mutans, by measuring the inhibition halos in 1-h and 15-d specimens. Data were analyzed by ANOVA. RESULTS: Solubility increased with higher ZnSO(4) content, but remained below the ISO 7489 limit. Flexural strength was not affected by ZnSO(4) addition, and Vitremer performed better than Ketac-Fil. The control materials released no zinc. Vitremer with 10% ZnSO(4) released the highest amount of zinc. Fluoride release was similar for Ketac-Fil and Vitremer. In both cases, the highest amounts were released in the first 24 h. The growth inhibition halo of S. mutans was similar for both materials with highest content of ZnSO(4) and occurred only with 1-h specimens. SIGNIFICANCE: Zinc addition decreased microorganisms growth and improved fluoride release, without significantly affecting the materials' flexural strength and solubility.  相似文献   
78.
Burkitt’s lymphoma is a high-grade, rapidly growing B-cell neoplasm. It is recognized by its aggressive course, brief median survival, and low rates of long-term survival. The authors discuss the case of a patient who acutely presented with intraabdominal complications from a new onset of Burkitt’s lymphoma. The clinical and pathological features, staging, treatment options, and survival data are reviewed. In addition, the role of surgical intervention is carefully analyzed.  相似文献   
79.
Glutathione-S-transferase (GST) genes encode a family of detoxification enzymes that offer protection against endogenous and exogenous sources of reactive oxygen species (ROS). Germline variations in GST genes may alter the catalytic efficiency of GST isoenzymes leading to a potential increase in susceptibility to the genotoxic effects of ROS and electrophilic substances. A nested case-control study design was used to examine the association between the polymorphic GST genes and prostate cancer risk among Finnish male smokers of the ATBC Cancer Prevention Study. A case-case analysis was used to determine the association between these genetic polymorphisms and prostate cancer progression. Germline DNA was obtained from 206 prostate cancer cases and 194 controls frequency matched on age, intervention group and study clinic. Cases and controls were genotyped for three GST genes using MALDI-TOF mass spectrometry or multiplex polymerase chain reaction (PCR). Relative to the wild-type genotype, we observed a 36% reduction in prostate cancer risk associated with the GST-M1-null genotype (odds ratio (OR) 0.64, 95% confidence interval (CI) 0.43, 0.95). Unlike GST-M1, GST-T1-null (OR 0.74, 95% CI 0.42, 1.33) and GST-P1*B (OR 1.10, 95% CI 0.72, 1.69) were not strongly associated with prostate cancer risk. We did not observe any significant associations between the selected polymorphic GST genes and tumour grade or stage. In conclusion, we did not observe a direct association between polymorphic GST-T1 or GST-P1 and prostate cancer risk. Our observation of a relatively strong inverse association between the GST-M1-null genotype and prostate cancer risk needs to be confirmed in larger association studies.  相似文献   
80.
We aimed to evaluate the potential of the cerebrospinal fluid (CSF) axonal damage biomarker NfH(SMI35) in the laboratory-supported differential diagnosis of parkinsonian syndromes. Patients with idiopathic Parkinson's disease (PD; n = 22), multiple-system atrophy (MSA; n = 21), progressive supranuclear palsy (PSP; n = 21), corticobasal degeneration (CBD; n = 6), and age-matched controls (n = 45) were included. CSF levels of NfH(SMI35) were measured using ELISA. Levels of CSF NfH(SMI35) were elevated in PSP compared to PD and controls (P < 0.05 each). They were also significantly higher in MSA than in PD and controls (P < 0.05 each). NfH(SMI35) differentiated PD from PSP with a sensitivity of 76.5% and a specificity of 94.4%. Axonal damage as measured by CSF NfH(SMI35) is most prominent in the more rapidly progressive syndromes PSP and MSA as compared to PD or CBD. CSF NfH(SMI35) may therefore be of some value for the laboratory-supported differential diagnosis of atypical parkinsonian syndromes.  相似文献   
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