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131.

Background

The street-food industry lacks legal recognition, it operates in unstable and precarious conditions, involving women and men with minimal or no knowledge of hygienic food handling practices. Infective eggs, bacteria, toxins and cysts of faecal orally transmissible parasites are common agents responsible for food contamination in developing countries.

Objective

To determine the incidence of digestive faecal-oral parasites among street-food vendors in Buea, South-west region of Cameroon,

Methods

From March to May 2009, physical and laboratory analysis of stool samples of 150 randomly selected street-food vendors, residing in four different zones in the municipality were carried out. Information on environmental and personal hygiene was also collected.

Results

Results revealed that 56.7% of the sampled population was infected with faecal-oral parasites. The major faecal-oral parasites detected in stool samples were: Entamoeba coli (14.0%), Entamoeba histolytica (12.67%), Ascaris lumbricoides (11.33%), Ankylostoma duodenalis (10.67%). Childcare activities, lack of deworming, poor personal hygiene, poor sanitary and toilet facilities, were factors promoting the spread of faecal-oral infections.

Conclusion

Food vendors should be educated on personal hygiene and safe food handling measures. Regulatory procedures on environmental hygiene and regular medical and paramedical follow up of food vendors should be enforced.  相似文献   
132.

Background

Pain is a common and major problem among nursing home residents. The prevalence of pain in elderly nursing home people is 40–80%, showing that they are at great risk of experiencing pain. Since assessment of pain is an important step towards the treatment of pain, there is a need for manageable, valid and reliable tools to assess pain in elderly people with dementia.

Methods

This systematic review identifies pain assessment scales for elderly people with severe dementia and evaluates the psychometric properties and clinical utility of these instruments. Relevant publications in English, German, French or Dutch, from 1988 to 2005, were identified by means of an extensive search strategy in Medline, Psychinfo and CINAHL, supplemented by screening citations and references. Quality judgement criteria were formulated and used to evaluate the psychometric aspects of the scales.

Results

Twenty-nine publications reporting on behavioural pain assessment instruments were selected for this review. Twelve observational pain assessment scales (DOLOPLUS2; ECPA; ECS; Observational Pain Behavior Tool; CNPI; PACSLAC; PAINAD; PADE; RaPID; Abbey Pain Scale; NOPPAIN; Pain assessment scale for use with cognitively impaired adults) were identified. Findings indicate that most observational scales are under development and show moderate psychometric qualities.

Conclusion

Based on the psychometric qualities and criteria regarding sensitivity and clinical utility, we conclude that PACSLAC and DOLOPLUS2 are the most appropriate scales currently available. Further research should focus on improving these scales by further testing their validity, reliability and clinical utility.  相似文献   
133.
134.
Chang  KL; Albujar  PF; Chen  YY; Johnson  RM; Weiss  LM 《Blood》1993,81(2):496-501
The Epstein-Barr virus (EBV) has been implicated in the pathogenesis of Hodgkin's disease (HD). This study was undertaken to determine whether the association of EBV with HD showed geographical variation, as in Burkitt's lymphoma. We studied 32 formalin-fixed, paraffin-embedded cases of HD occurring in Peru. EBV DNA-RNA in situ hybridization was performed using a 30-base biotinylated antisense oligonucleotide complementary to the EBER1 gene of EBV. EBV immunohistochemistry was also performed, using a monoclonal antibody (MoAb) to the latent membrane protein (LMP1) of EBV. Identification of the precise cellular subset staining with EBV was accomplished via double-labeling with MoAbs directed against Reed-Sternberg cells (LeuM1/CD15) and B cells (L26/CD20). EBV RNA was identified in all or virtually all of the Reed- Sternberg cells and variants in 30 of the 32 (94%) cases of HD by in situ hybridization. LMP1 expression was identified in 83% of the EBER1- positive cases. Double-labeling studies confirmed the localization of EBV RNA to CD15-expressing Hodgkin's cells. This study found an extremely high prevalence of EBV in Peruvian HD, in contrast to the much lower percentage of EBV-associated cases of HD occurring in "Western" patients.  相似文献   
135.
目的:探讨新型输送型球囊扩张导管(Fastunnel)在颅内动脉粥样硬化狭窄介入治疗中的应用效果。方法:2021年11月至2022年2月,我们使用新型输送型球囊扩张导管对10例颅内动脉粥样硬化狭窄的患者进行了球囊扩张+支架成形术。收集并分析了患者的基线情况、影像学特点、治疗情况及围手术期情况。结果:男6例,女性4例,平均年龄(62.7±6.7)岁。10例患者均成功接受手术治疗,手术时长为16~65(37.3±18.2)min,治疗过程所受辐射剂量为1381~4901(2643.7±1131.7)mGy,剂量面积乘积(DAP)值为5707~38112(17526.8±10809.5)μGym2围手术期无出血及缺血相关并发症。结论:输送型球囊扩张导管具有较好的安全性,能有效地简化手术步骤、缩短手术时间,对减少患者及医生所受射线剂量。  相似文献   
136.
137.
酵母苯丙氨酸tRNAphe反密码区域核苷修饰的几率和种类远超过T环和D环.在17个核苷酸的序列中,5种转录后的自然修饰在32,34,37,39和40位.为研究核苷修饰与结构和功能的关系,需建立一种研究方法和模型体系,从技术上,本方法和化学修饰核苷[1]、自动合成、色谱法纯化和定性分析[2]、热变性和热力学分析[3]、生化检测[4]5个不同学科相关.为探讨一种系统的方法,测定修饰核苷对酵母苯丙氨酸tRNAphe反密码环结构与功能的影响,从原子水平上区别和理解尿嘧啶和假尿嘧啶甲基化对结构与功能的影响,进行了以下的实验研究.  相似文献   
138.
用小鼠肝细胞核制备和肝微粒体制备,研究了化合物SY640对致癌剂苯并芘(BP)损伤肝细胞核的保护作用及与P450的关系。结果表明,SY640可显著抑制3HBP与小鼠肝细胞核的DNA共价结合。SY640连续po3d,可显著诱导小鼠肝微粒体细胞色素P450含量及氨基比林脱甲基酶活性;给药1次2h内却只抑制氨基比林脱甲基酶活性。体外温孵实验表明,SY640对小鼠肝微粒体氨基比林脱甲基酶活性也具有明显的抑制作用。差示光谱分析表明,SY640可与细胞色素P450形成络合物。提示该化合物对肝微粒体细胞色素P450酶系的影响与其对化学致癌剂BP所致肝细胞毒性的保护作用有关。  相似文献   
139.
Twenty children with acute lymphoblastic leukemia in second (18 patients) or third (two patients) complete remission after bone marrow relapse received allogeneic bone marrow transplants from histocompatible sibling donors. The preparative regimen for marrow transplantation consisted of 12 doses of 3,000 mg/m2 cytosine arabinoside twice daily for six days followed by 1,200 cGy total-body irradiation (six doses of 200 cGy twice daily for three days). The preparative regimen was well tolerated, and all patients showed marrow engraftment promptly. Twelve patients are alive in complete remission 12+ to 79+ months posttransplant; eight patients are over 48 months posttransplant. Six patients died 1 to 9 months posttransplant of nonleukemic causes: (two each of graft-v-host disease, interstitial pneumonitis, and infection). Two patients developed recurrent leukemia at 15 and 30 months posttransplant. Both have died at 19 and 36 months posttransplant. Life table analysis reveals an actuarial survival and event-free survival rate of 58% and a marrow relapse rate of 17%. These results suggest that high-dose cytosine arabinoside and fractionated total-body irradiation is a relatively nontoxic and highly effective preparative regimen for allogeneic bone marrow transplantation for acute lymphoblastic leukemia that deserves further evaluation.  相似文献   
140.
Nievelstein  PF; Sixma  JJ 《Blood》1988,72(1):82-88
Previous studies have indicated that activated blood platelets interact with fibronectin through binding of fibronectin to the glycoprotein IIb- IIIa complex (GPIIb-IIIa). The cell attachment site of fibronectin with its crucial arg-gly-asp(-ser) [RGD(S)]sequence is involved in these bindings. We studied the importance of these interactions for the fibronectin dependence of platelet adhesion under flow conditions. An RGDS-containing hexapeptide (GRGDSP) was compared with a nonreactive control peptide (GRGESP). The GRGDSP-peptide inhibited thrombin-induced aggregation and adhesion under static conditions at 0.1 mmol/L. This concentration had no effect on platelet adhesion to nonfibrillar collagen type I in flow. GRGDSP at 1 mmol/L had a significant inhibitory effect at 1,500 s-1, but not at the lower shear rates of 800 and 300 s-1 where platelet adhesion is also fibronectin dependent. On the matrix of cultured human umbilical vein endothelial cells, 1 mmol/L GRGDSP had no effect on platelet adhesion. The relation between GPIIb- IIIa and fibronectin dependence was investigated with platelets of a patient with Glanzmann's thrombasthenia and monoclonal antibodies to GPIIb-IIIa using endothelial cell matrix (ECM) as a surface. Platelets of normal controls or a patient with Glanzmann's thrombasthenia showed a similar inhibition of adhesion in the presence of fibronectin-free plasma after the ECMs had been preincubated with antifibronectin F(ab')2 fragments. Incubation of platelets with anti-GPIIb-IIIa showed inhibition of platelet adhesion at high shear rates. Dependence on fibronectin for platelet adhesion was still observed even though separate experiments had shown that these anti-GPIIb-IIIa antibodies could block binding of radiolabeled fibronectin to thrombin-activated platelets. These data suggest the existence of another binding system for the interaction of platelets with fibronectin that may only appear when fibronectin is present on a surface.  相似文献   
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