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91.
Protozoal infections of the gastrointestinal tract occur worldwide and have substantial morbidity and mortality. Prevalence is higher in the economically deprived regions of the world, especially the developing countries. Infections like amoebiasis and giardiasis have a worldwide distribution, being endemic in India. Apart from producing GI symptoms, growth and development of children is also impaired. It is seen that protozoa multiply rapidly in their hosts and as there is a lack of effective vaccines, chemotherapy has been the only practiced way to treat individuals and reduce transmission. The current treatment modalities for protozoal diarrhoea include 5-nitrosoimidazoles, iodoquinol, diloxanide furoate, paromomycin, chloroquine, and trimethoprim-sulphamethoxazole.  相似文献   
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Combined liver and kidney transplantation is the ideal treatment for patients with end-stage renal failure secondary to primary hyperoxaluria and systemic oxalosis, with a functioning liver providing replacement of the deficient enzyme and a functioning kidney providing the route of excretion for the oxalate crystals. Pancytopenia from bone marrow infiltration of oxalate crystals is a rare complication of primary hyperoxaluria, and its reversal following transplant has not been described. We report the first case of pancytopenia from marrow infiltration by oxalate crystals reversing following a successful kidney transplant alone. Although kidney alone transplants do not provide the best chance of survival or quality of life as compared to a combined kidney and liver transplant, a well functioning kidney transplant is able to take care of the systemic oxalate load and ameliorate, at least for a period of time, the systemic complications of oxalosis.  相似文献   
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This study tested the hypothesis that dietary arginine supplementation increases endothelial tetrahydrobiopterin (BH(4)) availability for nitric oxide (NO) synthesis in diabetic rats. Streptozotocin-induced diabetic rats either were given unrestricted access to a casein-based diet (Expt. 1) or were pair-fed the diet on the basis of the food intake per kg of body weight of nondiabetic rats (Expt. 2). Beginning 1 d after vehicle or streptozotocin injection, arginine-HCl (1.51%) or alanine (isonitrogenous control, 2.55%) was added daily to the drinking water for nondiabetic rats, whereas concentrations were adjusted (0.43% arginine-HCl and 0.73% alanine) in the drinking water for diabetic rats (which consumed more water) to ensure isonitrogenous provision. At 2 wk after the initiation of arginine supplementation, coronary endothelial cells and plasma were obtained for the measurement of NO synthesis and metabolites. In both experiments, plasma and endothelial concentrations of N(G)-monomethylarginine, asymmetric dimethylarginine, and symmetric dimethylarginine increased, but those of arginine as well as endothelial BH(4) availability and NO synthesis decreased in diabetic rats, compared with nondiabetic rats. In both diabetic and nondiabetic rats, arginine supplementation increased plasma concentrations of arginine and insulin, endothelial concentrations of arginine and BH(4), and endothelial NO synthesis, but did not affect plasma and endothelial concentrations of methylarginines or plasma concentrations of homocysteine. Dietary arginine supplementation or provision of a BH(4) precursor normalized endothelial NO synthesis in diabetic rats. Arginine supplementation did not affect plasma glucose levels in nondiabetic rats, but reduced body weight loss and plasma glucose levels in diabetic rats. Thus, dietary L-arginine supplementation stimulates endothelial NO synthesis by increasing BH(4) provision, which is beneficial for vascular function and glucose homeostasis in diabetic subjects.  相似文献   
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In September 2001, a waterborne outbreak of gastroenteritis occurred in eastern France. Of 31 fecal samples from symptomatic individuals, 19 tested positive for Cryptosporidium with two PCRs targeting the Hsp70 and the 18S rRNA genes of CRYPTOSPORIDIUM: Sequencing of the PCR fragments produced sequences identical to that of Cryptosporidium parvum genotype 1.  相似文献   
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BACKGROUND: This is a retrospective study of left ventricle (LV) aneurysm repair done at the Escorts Heart Institute and Research Centre, New Delhi, since October 1988. Two methods of LV aneurysm repair are practiced: double breasting (DB) and Dor's repair. The method varies with location, size, and extent of aneurysm and quality of the fibrotic wall of the aneurysm. METHODS: Between October 1988 and May 2001, 129 patients underwent LV aneurysm repair using one of the two techniques; 78 patients had Dor's repair while 51 patients had DB repair. RESULTS: Overall mortality was 2.3% (three patients). One patient died in the DB group, and two patients died in the Dor's repair group. Mean preoperative ejection fraction (EF) after surgery in DB was 31% while in Dor's repair it was 29.2%. EF showed improvement after surgery to 48.5% in DB and 46.6% in Dor's repair. Decrease in end-diastolic volume (EDV) in DB was from 146 to 91.4 cm3/m2, and in Dor's repair it was from 156 cm3/m2 to 88.6 cm3/m2. Decrease in end-systolic volume was from 101 cm3/m2 to 60.2 cm3/m2 in DB and from 109 cm3/m2 to 64.5 cm3/m2 in Dor's group. All of these values showed statistically significant improvement. At six months postoperatively, 83 patients (74.1%) out of 112 patients who were preoperatively in New York Heart Association (NYHA) Functional Classes III and IV improved to class II while 7 patients (6.3%) improved to class I. CONCLUSION: In our experience Dor's repair is indicated for anteroseptal and apical isolated posterior aneurysm to restore LV volume and geometry while DB is indicated for apical, anterolateral, and lateral aneurysms where septal involvement is less. These two techniques have definite indications and advantages with good results.  相似文献   
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The object of our study is to project the impact of a prophylactic vaccine against persistent human papillomavirus (HPV)-16/18 infection on age-specific incidence of invasive cervical cancer. We developed a computer-based mathematical model of the natural history of cervical carcinogenesis to incorporate the underlying type-specific HPV distribution within precancerous lesions and invasive cancer. After defining plausible ranges for each parameter based on a comprehensive literature review, the model was calibrated to the best available population-based data. We projected the age-specific reduction in cervical cancer that would occur with a vaccine that reduced the probability of acquiring persistent infection with HPV 16/18, and explored the impact of alternative assumptions about vaccine efficacy and coverage, waning immunity and competing risks associated with non-16/18 HPV types in vaccinated women. The model predicted a peak age-specific cancer incidence of 90 per 100,000 in the 6th decade, a lifetime cancer risk of 3.7% and a reproducible representation of type-specific HPV within low and high-grade cervical precancerous lesions and cervical cancer. A vaccine that prevented 98% of persistent HPV 16/18 was associated with an approximate equivalent reduction in 16/18-associated cancer and a 51% reduction in total cervical cancer; the effect on total cancer was attenuated due to the competing risks associated with other oncogenic non-16/18 types. A vaccine that prevented 75% of persistent HPV 16/18 was associated with a 70% to 83% reduction in HPV-16/18 cancer cases. Similar effects were observed with high-grade squamous intraepithelial lesions (HSIL) although the impact of vaccination on the overall prevalence of HPV and low-grade squamous intraepithelial lesions (LSIL) was minimal. In conclusion, a prophylactic vaccine that prevents persistent HPV-16/18 infection can be expected to significantly reduce HPV-16/18-associated LSIL, HSIL and cervical cancer. The impact on overall prevalence of HPV or LSIL, however, may be minimal. Based on the relative importance of different parameters in the model, several priorities for future research were identified. These include a better understanding of the heterogeneity of vaccine response, the effect of type-specific vaccination on other HPV types and the degree to which vaccination effect persists over time.  相似文献   
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