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Some 4- and 2-(nitrobenzyloxycarbonyl)-1, 2-bis(methylsulfonyl)-1-(2-chloroethyl)hydrazines (4, 6, and 7) were synthesized and evaluated for their ability to exert preferential toxicity to hypoxic EMT6 mammary carcinoma cells using a colony-forming assay. Of these, the 4,5-dimethoxy-2-nitro analogue 6 (50 microM, 1-h exposure) caused greater than 3 logs of kill of hypoxic cells, with relatively minor toxicity to corresponding aerobic cells. The ability of 4-nitro (4) and 4,5-dimethoxy-2-nitro (6) analogues to reach and kill hypoxic cells of solid tumors was also demonstrated using intradermally implanted EMT6 solid tumors in mice. In addition, a possible source of toxicity to normal tissue, i. e., the activation of the 4-nitrobenzyl derivative 4 by glutathione S-transferase-catalyzed thiolysis, was essentially eliminated by replacing one of the benzylic methylene protons by a methyl group. The 4-nitro (4) and 4,5-dimethoxy-2-nitro (6) analogues also appear to be reduced more easily under acidic conditions (pH 6.0) than under neutral conditions, as measured by differential pulse polarography. Since the pH in hypoxic regions is often lower than that in adjacent aerobic regions, this property should aid in the cytotoxic action of these agents against hypoxic cells of solid tumors.  相似文献   
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Weaning and food supplementation practices were examined in a 12-month prospective study of 200 mother-infant pairs from a rural area of Sewagram, India. Only 2 mothers (1%) began weaning before 4 months of age. Between 4 and 6 months, 76 (38%) mothers initiated weaning; at 6 months, this rate was 61%. Illiterate women and mothers with a primary school education, multiparas, and those living in joint families were most likely to defer weaning until after 6 months. Health education campaigns focused on the importance of exclusive breast feeding for the first 4-6 months, followed by the introduction of semisolid foods, are recommended.  相似文献   
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Hanging is one of the most common methods of suicide in India in which death of the individual occurs instantaneously. However, a few cases have been reported in literature in which death has occurred after a certain period of time or the patient has survived after prolonged resuscitative measures. A case of a 20-year-old female is described who survived for nine days after hanging, remaining unconscious throughout in the hospital. She died due to cerebral damage caused by cerebral anoxia.  相似文献   
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Growth rate of non‐vestibular intracranial schwannomas A group of nine patients with non‐vestibular intracranial neuromas (four jugular, four facial, one trigeminal) underwent an interval scanning management policy, with serial annual magnetic resonance (MR) imaging. Tumour volume was assessed by manual measurement of the tumour area by MR imaging. Tumour volume was assessed by manual measurement of the tumour area on MR imaging axial cuts. The mean tumour size at presentation was 4.6 cm3 (range 0.7–17.8 cm3). During a mean follow‐up of 36 months (range 22–50 months), five out of nine tumours grew significantly at a rate of more than 5% of their initial volume per year. Only those tumours growing at a rate of more than 20% initial volume per year exhibited symptom progression. During a 36‐month period of interval scanning, just over 50% of non‐vestibular intracranial neuromas exhibited significant growth. Symptom progression was found to be a strong indicator of a high growth rate. This proportion exhibiting growth is higher than that demonstrated by unilateral sporadic vestibular schwannomas, but less than in patients with neurofibromatosis II. Early treatment of non‐vestibular intracranial neuromas should therefore be considered.  相似文献   
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Indian Journal of Pediatrics - To evaluate effect of one year exercise intervention program on bone mineral accrual in children and adolescent with cystic fibrosis (CF). Fifty-two CF children (mean...  相似文献   
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Introduction  Liver disease and the development of hepatic fibrosis are complications associated with total parenteral nutrition (TPN). Patients developing cirrhosis and portal hypertension in the setting of intestinal failure have a high mortality and may require combined liver and intestinal transplantation which carries much higher morbidity and mortality than isolated intestinal transplantation. Discussion  Recently, regression of hepatic fibrosis in patients with TPN liver disease has been described following intestinal transplantation. To date, there has been no demonstration of the reversal of established cirrhosis due to long-term TPN injury. Herein, we describe a patient with intestinal failure who developed cirrhosis from long-standing TPN injury and underwent isolated intestinal transplantation. He had no overt clinical stigmata of portal hypertension and had preserved liver function. Serial liver biopsies were reviewed and assessed with standard histology and quantitation of fibrosis using image analysis. Dramatic regression of fibrosis and reversal of cirrhosis were observed 17 months posttransplantation. Image analysis demonstrated a 14% total decrease in the percentage area of fibrosis. Conclusions  Cirrhosis related to TPN may be rapidly reversible after isolated intestinal transplantation. Such patients may be able to undergo isolated intestinal transplantation if they do not have hepatic synthetic compromise or clinical stigmata of portal hypertension.  相似文献   
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