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91.
We interviewed 108 sickle cell anaemia patients aged 5 years older on priapism, and 113 healthy subjects in a control group. They were recruited in the out-patient consultation of the two sickle cell anemia care units of the Fann teaching hospital in Dakar. Ten cases of priapism were identified, all in the group of sickle cell patients (the difference is significant, p = 0.004). Prevalence of priapism was 9.3%. Actuarial probability of having priapism was 8.3% by 10 years of age, and 38.9% +/- 5.7 by 20 years of age. Before the interview, only 10.2% of the sickle cell patients and 8% in the control group knew about priapism, and most of them were unaware of its association with sickle cell disease (75% of sickle cell anaemia patients and 80% of control subjects). This lack of information should be improved by an educational program.  相似文献   
92.
Epidemiological and clinical features of HIV-2 infection in Dakar   总被引:1,自引:0,他引:1  
OBJECTIVE: The aim of this article was to describe the epidemiological and clinical aspects of HIV-2 infection in Dakar. DESIGN AND METHODS: This retrospective study was made on 217 HIV-2 infected patients hospitalized between 1986 and 2003; the epidemiological, clinical, and paraclinical data was collected and analyzed using the Epi-Info software version 6.04. RESULTS: The mean age was 40 years+/-9.6 and the male to female sex ratio was 1.33. The mode of transmission was primarily heterosexual. Some risk factors (travel abroad, heterosexual multi-partners, and unprotected sexual intercourse) were more frequently observed in men while others (blood transfusion, HIV positive partners) were noted among HIV-2 infected women. The most frequent symptoms were weight loss (88%), diarrhea (77%), fever (72.4%), asthenia (70.5%), chronic cough, and dermatosis (50.7%). The main opportunistic infections were oral candidiasis (61.8%), tuberculosis (26.3%), intestinal parasitosis (20.3%). The lethality rate was 33.2% and it was correlated with a low CD4 rate. Meningoencephalitis and bacterial infections were associated with a high lethality rate. CONCLUSIONS: The epidemiological and clinical aspects of HIV-2 infection were the same as in HIV-1 infected patients. However the lethality rate remained high among patients hospitalized with a low CD4 cell count. Early HIV testing and improving the diagnostic approach for opportunistic infections remains a high priority.  相似文献   
93.
94.
A group of 110 individuals with Schistosoma mansoni infection was investigated. Patients were allocated to one of three treatment groups and given artesunate or praziquantel alone or both in combination. Combined artesunate-praziquantel significantly increased the number of individuals cured at 5 weeks post-treatment, but at 12 weeks was only better than artesunate alone and at 24 weeks there was no statistically significant difference between the three groups. Egg count reduction rate was similar to the rate obtained with praziquantel used alone.  相似文献   
95.
96.
OBJECTIVE: To evaluate the presence of histones and nucleosomes in cell lysates of freshly isolated peripheral blood mononuclear cells (PBMC), fully activated lymphoblasts, or lymphoblasts after induction of apoptosis. METHODS: Each histone class (H1, H2A, H2B, H3, and H4) was detected by western blot analysis with specific antibodies. Annexin V/propidium iodide (PI) staining was performed for each treatment to distinguish viable, early, and late apoptotic, and necrotic cells. DNA degradation was evaluated by PI staining in a hypotonic buffer. RESULTS: All five histones were detected in cell lysates of activated lymphoblasts in higher concentrations than in lysates of PBMC. An additional significant increase of H2A, H2B, H3, H4, and complete nucleosomes in cell lysates of lymphoblasts was found during interleukin (IL)2 deprivation for 8 or 24 hours. The content of these histones or nucleosomes in cell lysates decreased after delayed IL2 readdition. H1 content in cell lysates was not affected by IL2 deprivation or addition. Quantities of H2A, H2B, H3, and H4 in cell lysates correlated significantly with signs of early apoptosis. UV-B light exposure or etoposide treatment of lymphoblasts resulted in a distinct increase for each histone class in cell lysates compared with standard curves. No bands for post-translationally modified histones were detected in cell lysates in contrast with signals in nuclear preparations. CONCLUSION: Extranuclear accumulation of histones and nucleosomes is an early event of apoptosis in human lymphoblasts. Dysregulation of early apoptosis might support the induction of autoimmunity against nuclear components.  相似文献   
97.
98.

Objective

We compared and evaluated the differences between two models for treating bilateral breast cancer (BBC): (i) dose–volume-based intensity-modulated radiation treatment (DV plan), and (ii) dose–volume-based intensity-modulated radiotherapy with generalised equivalent uniform dose-based optimisation (DV-gEUD plan).

Methods

The quality and performance of the DV plan and DV-gEUD plan using the Pinnacle3® system (Philips, Fitchburg, WI) were evaluated and compared in 10 patients with stage T2–T4 BBC. The plans were delivered on a Varian 21EX linear accelerator (Varian Medical Systems, Milpitas, CA) equipped with a Millennium 120 leaf multileaf collimator (Varian Medical Systems). The parameters analysed included the conformity index, homogeneity index, tumour control probability of the planning target volume (PTV), the volumes V20 Gy and V30 Gy of the organs at risk (OAR, including the heart and lungs), mean dose and the normal tissue complication probability.

Results

Both plans met the requirements for the coverage of PTV with similar conformity and homogeneity indices. However, the DV-gEUD plan had the advantage of dose sparing for OAR: the mean doses of the heart and lungs, lung V20 Gy, and heart V30 Gy in the DV-gEUD plan were lower than those in the DV plan (p<0.05).

Conclusions

A better result can be obtained by starting with a DV-generated plan and then improving it by adding gEUD-based improvements to reduce the number of iterations and to improve the optimum dose distribution.

Advances to knowledge

The DV-gEUD plan provided superior dosimetric results for treating BBC in terms of PTV coverage and OAR sparing than the DV plan, without sacrificing the homogeneity of dose distribution in the PTV.Breast cancer is the most common cancer and the leading cause of cancer deaths in females worldwide, with about 500 000 fatalities each year. In the USA and Europe, breast cancer constitutes, on average, one in four cancer cases among females [1,2]. Breast cancer among females in Asian countries mostly occurs between the ages of 40 and 50 years; however, in females in Western countries, it mostly occurs between the ages of 50 and 60 years [2,3].Bilateral breast cancer (BBC) is very rare, accounting for only 1–3% of all breast cancer cases [4-6]. Generally, no treatment guidelines exist for BBC. The treatment of BBC relies on surgery, chemotherapy and radiation therapy; additionally, BBC has previously demonstrated a poor prognosis. Current evidence indicates that the survival rate of patients with BBC is similar to that of patients with unilateral breast cancer [7,8]. The difficulty in treatment planning for BBC varies greatly, case by case, and is thus a great challenge for radiotherapy. Important issues have been raised concerning how to reduce the dose of radiation to normal tissues, how to maintain a certain tumour control probability (TCP) and how to improve the quality of life for patients with BBC.Most intensity-modulated radiotherapy (IMRT) planning systems apply dose–volume (DV)-based objective functions for dose optimisation, and an acceptable plan can be generated in most cases. For more complex plans, more iterations are required because many parameters need to be finely tuned. A successful improvement tool—the generalised equivalent uniform dose (gEUD)—was developed with fewer parameter settings [9-13] to improve the quality of plans. However, gEUD-based optimisation cannot demonstrate such advantages on the first run; more iterations are required to sculpt the dose distribution [14].To overcome the disadvantages mentioned above, we started with a DV-generated plan, and then improved it by adding gEUD-based improvements. The goal was to reduce the number of iterations and to improve the optimum dose distribution. This method first determined the approximate solutions for most of the treatment targets by DV-based optimisation, and then adjusted the DV histogram (DVH) by gEUD-based optimisation to obtain a superior solution. This study also compared and evaluated the differences between two different methods for the treatment of BBC—(i) a DV plan with DV-based optimisation (DV plan), and (ii) a DV-gEUD plan with mainly DV-based optimisation assisted by gEUD-based optimisation (DV-gEUD plan)—thus providing a quantitative indicator model for reference.  相似文献   
99.
Central nervous system toxicity of 5-FU could show various manifestations, such as decreased alertness, disorientation, and agitation. It is generally accepted that lesions of 5-FU encephalopathy are mainly in the deep cerebral white matter and corpus callosum on MR imaging. Here we describe a case of 5-FU encephalopathy in gastric cancer with an atypical reversible diffusion-restricted lesion on MR imaging, showing bilateral basal ganglia, thalami, and parasagittal frontal cortex involvement on diffusion and T2-weighted imaging.  相似文献   
100.
Since the few indirect markers available for assessing the development and the stage of intestinal schistosomiasis morbidity are weakly specific, endoscopy is still the only method able to detect severe forms of pathology. Therefore, we evaluated the isotype antibody response to the current schistosome antigen preparation (soluble egg antigens [SEA]) in 142 Senegalese patients infected with Schistosoma mansoni. They were stratified into three different stages of pathology according to ultrasonographic, endoscopic, and clinical parameters (stage 1 = no detectable pathology; stage 2 = moderate morbidity; stage 3 = severe forms of pathology). Only median specific IgG4, IgE, and IgA responses changed according to the stage of pathology. The IgA level was significantly higher in stages 2 and 3 compared with stage 1, and the IgE level was higher in stage 3 compared with stage 1. A high specific IgG4 level was observed only in stage 3 and was significantly different compared with stage 2. We show an association between the variability of the specific response to SEA and the degree of morbidity, and demonstrate that IgA and IgG4 responses could be combined markers to easily discriminate the different stages of pathology due to infection with S. mansoni.  相似文献   
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