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1.
Joseane Balan Da Silva Gleison Daion Piovezana Bossolani Camila Piva Greicy Brisa Malaquias Dias Jancarlo Gomes Ferreira Diogo Francisco Rossoni 《International journal of environmental health research》2016,26(5-6):578-588
The spatial distribution of enteroparasitosis in an indigenous village from Paraná was evaluated to identify areas of risk for these infections. A cross-sectional study (from November 2010 to June 2011) was performed using Three Faecal Test® and Kato &; Katz method and a questionnaire on housing and hygiene conditions was administered. Local geostatistical analyses were performed to determine the spatial distribution of intestinal parasitic infections. The overall prevalence of enteroparasites was 67.2?% (457/680), and the most prevalent taxa were Ascaris lumbricoides (48.8?%) and Trichuris trichiura (44.7?%). The prevalence of heavy infection by soil-transmitted helminths was 3.6?% and the families lived in houses with an average of 5.1 residents and < 2 bedrooms per household. The average number of species per individual present spatial heterogeneity with the highest values (≥0.8) in areas with high clustering of residences. The visualization of the spatial distribution of intestinal parasites in this indigenous village is an important contribution to determining health risk areas and planning decisions and services. 相似文献
2.
Multivariate survival data are frequently encountered in biomedical applications in the form of clustered failures (or recurrent events data). A popular way of analyzing such data is by using shared frailty models, which assume that the proportional hazards assumption holds conditional on an unobserved cluster-specific random effect. Such models are often incorporated in more complicated joint models in survival analysis. If the random effect distribution has finite expectation, then the conditional proportional hazards assumption does not carry over to the marginal models. It has been shown that, for univariate data, this makes it impossible to distinguish between the presence of unobserved heterogeneity (eg, due to missing covariates) and marginal nonproportional hazards. We show that time-dependent covariate effects may falsely appear as evidence in favor of a frailty model also in the case of clustered failures or recurrent events data, when the cluster size or number of recurrent events is small. When true unobserved heterogeneity is present, the presence of nonproportional hazards leads to overestimating the frailty effect. We show that this phenomenon is somewhat mitigated as the cluster size grows. We carry out a simulation study to assess the behavior of test statistics and estimators for frailty models in such contexts. The gamma, inverse Gaussian, and positive stable shared frailty models are contrasted using a novel software implementation for estimating semiparametric shared frailty models. Two main questions are addressed in the contexts of clustered failures and recurrent events: whether covariates with a time-dependent effect may appear as indication of unobserved heterogeneity and whether the additional presence of unobserved heterogeneity can be detected in this case. Finally, the practical implications are illustrated in a real-world data analysis example. 相似文献
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Elisa Faybush David C Mulligan Barry D Birch Joseph I Sirven Vijayan Balan 《Liver transplantation》2005,11(4):467-468
There are no published accounts of patients with ventriculoperitoneal shunts undergoing liver transplantation in the literature. Because patients with ventriculoperitoneal shunts are prone to infections, this may be a theoretical contraindication to transplantation. We present a case of a patient with cirrhosis who had a ventriculoperitoneal shunt placed many years prior to transplantation. The patient had no neurological complications and the shunt was intact and functioning. Prior to transplantation, the patient underwent a ventriculoperitoneal to ventriculopleural shunt conversion that was reversed posttransplantation. Apart from some minor complications, the patient has done remarkably well from a graft and neurological perspective. In conclusion, patients who have ventriculoperitoneal shunts may be considered for liver transplantation as the risk of infectious and neurological complications is low and there are no deleterious effects on graft survival. 相似文献
8.
This paper describes the tragic case of a young woman who died of cancer of
the colon after successfully donating eggs to her younger sister. Although
there is no direct link between her operation and the subsequent
development of bowel carcinoma, this case imparts a feeling of unease when
seen in conjunction with other cases reported during the last few years. It
is a reminder that little is known of the long-term consequences of some
aspects of assisted conception. Women undergoing ovarian stimulation for
themselves or a matched recipient have the right to be advised, in an
agreed format, that there is some concern about unproven potential risks
from the stimulatory drugs. The safety of egg donors must assume priority
over all other considerations, including lack of donors or any moral
position. The recent decision by the Human Fertilisation and Embryology
Authority (HFEA) to withdraw any form of payment or recompense to egg
donors does not seem to us to be based on a balance of scientific advances,
patient needs and the ethics of gamete supply. They state that the
intention to withdraw payments was implicit in the 1990 Human Fertilisation
and Embryology (HFE) Act. However the Act was based on the Warnock report
made 6 years earlier. Even in 1990 ovum donation was uncommon and fertility
drugs had not yet caused any unease. The Act provided the HFEA with
discretionary powers to issue directions so that the future policies would
be consistent with any emerging new medical evidence. It is imperative that
the HFEA provide convincing evidence on how the current policy of payment
to donors harms society, donors or recipients, and how in the UK the new
policy will improve medical practice in assisted conception. Successful
pilot studies must precede the implementation of any new policy. Failure to
do this could cause irreversible harm to the practice of assisted
conception using donor gametes, which will ultimately be against the basic
aims of the 1990 HFE Act.
相似文献
9.
Mutations in the Ca(2+)-sensing receptor gene cause autosomal dominant and sporadic hypoparathyroidism 总被引:3,自引:0,他引:3
Baron J; Winer KK; Yanovski JA; Cunningham AW; Laue L; Zimmerman D; Cutler GB Jr 《Human molecular genetics》1996,5(5):601-606
Parathyroid hormone secretion is negatively regulated by a 7- transmembrane
domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that
activating mutations in this receptor might cause autosomal dominant
hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified,
in two families with ADHP, heterozygous missense mutations in the
Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of
50 normal controls had either mutation. We also identified a de novo,
missense Ca(2+)-sensing receptor mutation in a child with severe sporadic
hypoparathyroidism. The amino acid substitution in one ADHP family affected
the N-terminal, extracellular domain of the receptor. The other mutations
involved the transmembrane region. Unlike patients with acquired
hypoparathyroidism, patients with these mutations had hypercalciuria even
at low serum calcium concentrations. Their greater hypercalciuria
presumably reflected activation of Ca(2+)-sensing receptors in kidney
cells, where the receptor negatively regulates calcium reabsorption. This
augmented hypercalciuria increases the risk of renal complications and thus
has implications for the choice of therapy.
相似文献
10.
Yang C Hillas P Tang J Balan J Notbohm H Polarek J 《Journal of biomedical materials research. Part B, Applied biomaterials》2004,69(1):18-24
Animal-tissue-derived collagen, containing mostly type I collagen with a minor amount of type III collagen, has been widely used in the production of hemostats for many decades, although it has been known for a long time that type III collagen is more likely to induce platelet aggregation in vitro. Because it is hard to purify type III from animal tissue, it has not been possible to correlate this finding with in vivo data. In this report, it is demonstrated that recombinant human collagen III fibrils are more capable of inducing platelet aggregation in vitro than those comprised of bovine collagen I, in agreement with previously published data on tissue-derived type III collagen. When formed into three-dimensional matrices, the use of type III collagen results in formulations with better mechanical integrity, larger surface area, and higher hemostatic activity in a rabbit spleen injury model as compared with commercially available hemostats formed from bovine type I collagen. 相似文献