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41.
Kabir Z 《International journal of epidemiology》2002,31(5):1075; author reply 1075-1075; author reply 1076
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42.
Chronic arsenic poisoning remains a public health crisis in Bangladesh. As arsenic has been shown to bind to human hemoglobin (Hb), hematologic mechanisms may play a role in the pathway through which arsenic exerts its toxicity. Two separate studies, a case-control and a cohort, were conducted to investigate the role of Hb in the development of arsenic-induced skin lesions. In the first, conditional logistic regression was used to investigate the effect of Hb on skin lesions among 900 case-control pairs from Pabna, Bangladesh, in which individuals were matched on gender, age, and location. In the second, mixed linear regression models were used to examine the association between toenail arsenic, urinary arsenic, and Hb within a cohort of 184 individuals from 50 families in the same region who did not have arsenic-induced skin lesions. Hb was significantly associated with skin lesions but this association was gender specific. In males, a 40% reduction in the odds of skin lesions occurred for every 1 g/dL increase in Hb (odds ratio, 0.60; 95% confidence interval, 0.49-0.73). No effect was observed for females (odds ratio, 1.16; 95% confidence interval, 0.92-1.46). In the cohort of 184 individuals, no associations between toenail arsenic or urinary arsenic species and Hb levels were observed. Low Hb levels may exacerbate the detrimental health effects of chronic arsenic poisoning. Whereas providing clean water remains the optimal solution to Bangladesh's problem of arsenic poisoning, improving nutrition and reducing iron-deficiency anemia may ameliorate negative health effects, such as skin lesions in individuals who have been exposed.  相似文献   
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It is common practice in therapeutic trials in Acute Lymphoblastic Leukaemia (ALL) to treat chemotherapy induced toxicities. In this study, 50 newly diagnosed ALL patients were enrolled and the median age was 14.5 years. 32 patients were male and 18 female. Prognostic factors were analysed. Remission induction, consolidation and maintenance therapy with conventional combination chemotherapy and CNS prophylaxis with intrathecal methotrexate and radiotherapy were instituted to all patients for long term event free survival. Results of induction therapy and overall outcomes of treatment were observed. Chemotherapy induced toxicities were also detected and treated accordingly. These toxicities were described in 4 groups depending on the frequency of their development in chemotherapy received patients. Haematological and gastrointestinal side effects and alopecia were expected i.e., developed in >75% of patients. Prednisolone and vincristine induced toxicities were common i.e., observed in >25% of patients. Hepatic complications and anthracycline induced tachycardia were occasional i.e., occurred in <25% and localized phlebitis and/ or soft tissue necrosis were rare and accidental i.e., developed in 5% of patients.  相似文献   
46.
The early events in lipopolysaccharide (LPS)-induced B-cell activation were investigated by studying the binding of 14C-labeled LPS to murine lymphocytes in vitro. In these studies we utilized intrinsically labeled 14C-labeled LPS from Salmonella minnesota or the 14C-labeled glycolipid derived from the Re mutant of S. minnesota (R595). Bone marrow-derived (B) lymphocytes bound more LPS than did thymus-derived (T) lymphocytes. Binding of LPS to murine spleen lymphocytes from strain C3H/HeN was compared with the binding to spleen lymphocytes from strain C3H/HeJ, a strain resistant to certain biological activities of LPS including mitogenesis. Spleen cells from both strains bound LPS equally well, suggesting that unresponsiveness of C3H/HeJ mice to LPS is due to factors other than a defect in binding of LPS. LPS binding to cells appeared to be due to a nonspecific interaction between the lipid moiety of LPS and the lipid components of the cell membrane. Thus, the highly lipophilic, polysaccharide-deficient glycolipid from R595 bound at least 20 times better than did LPS. Furthermore, partial removal of cell surface proteins with trypsin or sialic acids with neuraminidase enhanced glycolipid binding, suggesting that binding is not through a protein- or sialic acid-containing receptor. The binding of glycolipid to lymphocytes was only partially specific since unlabeled glycolipid R595, lipid A, and LPS did not completely inhibit the uptake of 14C-labeled glycolipid R595. In addition, binding could be inhibited by a nonmitogenic phospholipid (phosphatidyl ethanolamine), which also is consistent with a nonspecific lipid-lipid interaction. Experiments were performed to determine the relationship of LPS binding to lymphocyte activation in the lymphocytes. The process of activation of lymphocytes by LPS was a slow one, since LPS was required to be present in culture for at least 24 h in order to obtain significant lymphocyte activation, suggesting that the amounts of LPS bound earlier are either quantitatively or qualitatively insufficient to irreversibly activate the cell.  相似文献   
47.
Two cases of Burkitt lymphoma are reported who presented atypically with acute renal failure and significant proteinuria as initial features of the lymphoma. The cases underscore the need for high index of suspicion for Burkitt lymphoma in any child with rapidly enlarging kidneys and acute renal failure of obscured origin in parts of the world where Burkitt lymphoma is endemic.  相似文献   
48.
A 39-year-old housewife sustained inadvertent trauma to the right index finger about 6 years ago, whilst stitching clothes. A couple of weeks later, the site of trauma became hard and gritty. Ever since, it has progressed slowly, without any appreciable outward sign. It was not associated with any discomfort/pain. Consequent on an opinion from a surgeon, it was decided to operate on the right index finger. During the operation, under local anesthesia, a hard and gritty material was removed. The material was subjected to histopathologic study. Several stitches were applied to the wound. It failed to respond to antimicrobial therapy over a 4-week period, prompting the patient to seek another opinion. Examination of the skin surface revealed a plaque with an irregular configuration on and around the distal interphalangeal joint of the right index finger. It was erythematous and pigmented. The top of the plaque was irregular and had alternating elevations and depressions ( Fig. 1 ). Diascopy was negative for apple jelly nodule. A bacillus Calmette–Guérin (BCG) vaccination scar was identified on the left deltoid. There was no regional lymphadenopathy or systemic abnormality. Mantoux test with intradermal injection of 0.1 mL SPAN's tuberculin (purified protein derivative/5 tuberculin units/0.1 mL) (Span Diagnostic Ltd., Murat, India) was negative after 72 h. Investigations, including total and differential leukocyte count, erythrocyte sedimentation rate, serum biochemistry, and renal and liver function tests, were within the normal range, as was a chest X-ray.
Figure 1 Open in figure viewer PowerPoint Tuberculosis verrucosa cutis before (a) and after (b) antitubercular therapy (ATT)  相似文献   
49.
A 9-month-old boy presented with the complaints of loose motion, vomiting and difficulty in breathing. His scalp hairs were thin, brittle, and sparse and were of differing lengths with twisted appearance. Hair shaft microscopy revealed alternate light and dark segments and twisting of the hair shafts by 180 degrees along the axis. Serum copper levels were normal. The audiological testing revealed bilateral sensorineural hearing loss. Child was diagnosed as a case of Bjornstad Syndrome.  相似文献   
50.
Thoracic actinomycosis represents about one-fourth of all cases of the disease. Isolated pleural effusion due to Actinomycosis is rare. We report a case of right sided pleural effusion with discharging sinus in the right anterior chest wall. Actinomycosis was suspected and confirmed by microscopic identification of "sulfur granules" in the discharge of the sinus tract and also identification of gram-positive filamentous bacteria in the specimen of discharging sinus. The patient improved clinically and radiologically after treatment with intravenous penicillin G followed by oral penicillin and aspiration of pleural fluid.  相似文献   
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