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11.
This paper describes patterns of infestation with Tunga penetrans (L., 1758) within the poor community of Araruama municipality, State of Rio de Janeiro, Brazil, assessed by the number of persons and domestic animals parasitized. The overall prevalence of infestation was 49.2% (211 parasitized hosts) of the 429 examined. Humans (p < 0.01) and dogs (p < 0.01) were the most important hosts with 62.6% and 35.6% respectively. Dogs were considered as the potential infestation source to humans. Considering sex and age groups, both measures showed a significant difference (p < 0.01): female (62.2% infested of 143 examined) and male (43.9% infested of 98 examined). All age classes were found infested with significant difference (G = 42.5; p < 0.01) and most of the infestation occurred in children in the 0-9-year old category (27.3%). In contrast and based on mean of chigoe burden per person, the parasitic intensity was significantly higher on male than on female in all age categories, except for the 50+ (H = 27.1; p < 0.01) and decreasing with the increase of age (chi2 = 69.7, A = -124.6, p < 0.01). Growing urbanization, improved housing and sewage systems, use of appropriate footwear, examination of the feet principally in young children, antitetanus prophylaxis and reduction of stray dogs population are the major prophylactic methods recommended.  相似文献   
12.
The pBR322 plasmid containing the sequence encoding β-lactamase, the enzyme conferring resistance to ampicillin, was encapsulated in liposomes of different phospholipid composition and incubated with synchronized cells. In mitotic cells as compared to cells synchronized in G1, twice as many exogeneous DNA molecules were found associated with the cell nuclear DNA, when fluid, neutral liposomes were used. These liposomes are taken up by the cells mainly via endocytosis. When fluid, negatively charged liposomes were used as carriers about the same number of exogeneous DNA molecules were found associated with the nuclear DNA both in mitotic and in G1-synchronized cells. The efficiency for gene transfer of liposomes entering the cells by different mechanisms was further studied and expressed both by the fraction of the radioactive plasmid associated with the nuclear DNA and by the level of the β-lactamase activity detected in the transfected cells. It appears that liposomes entering the cells mainly via an energy-dependent mechanism are more efficient for this type of DNA transfer.  相似文献   
13.
Metabolic studies were done with 14C-Viprostol (I) administered by various routes (I.V., oral and topical) to six animal species and to man. Total radioactivity and metabolic profiles were analyzed in plasma, tissues and excreta. The main metabolites were isolated and identified by capillary GC/MS.Plasma and urinary metabolic profiles were qualitatively similar across species, with two major metabolic reactions being predominant: rapid hydrolysis to the pharmacologically active free acid (II)_ and oxidation of the alpha-chain to dinor and tetranor acids (III, IV). In the monkey and man, reduction of the 9-keto group lead to PGF2 type metabolites (VI–VIII). In the rat, omega oxidation of the beta-chain occurred as well, resulting in the formation of dicarboxylic acids (V).  相似文献   
14.
A common photosensitive polymeric material used in semiconductor microlithography (diazo-naphto-quinone/novolak resist) was pattern-exposed with near-UV light to create carboxylic-rich areas on the polymer surface. The patterned surfaces were further functionalised via: (1) the anchorage of peptides for specific cell-attachment or cell-detachment functions; or (2) the diffusion of silicon rich chemical species to achieve the cell detachment. Pairs of antagonistic surface characteristics controlled the cell attachment: (1) amino-rich or carboxylic-rich surfaces; and (2) hydrophilic or hydrophobic surfaces; in which the former promoted the adhesion. It was found that common microlithographic materials and techniques can be upgraded to allow an effective control of the lateral organisation of the artificial arrays of neuronal and glia cells.  相似文献   
15.
The study was set up to evaluate the impact of two commercial larvicide formulations, Bacillus thuringiensis serovar israelensis base (Bti) at 15 ppm/1 min and temephos at 0.03 ppm of active ingredient, used to control Simulium pertinax populations, on associated non-target entomofauna occupying the same breeding sites. The experiments were carried out on the Pedra Branca and Muricana rivers, on the slopes of Serra do Mar massif, municipality of Paraty, state of Rio de Janeiro, Brazil. Bti was applied to the river Pedra Branca and temephosto theriver Muricana. On both rivers, treatment and control sections were labeled as such, each one with two observation posts: slow moving water and fast water regions respectively. Artificial substrata was used to evaluate the abundance of associated entomofauna. Attached immature stages of arthropods were removed from both of its surfaces fortnightly. Were collected, from the two rivers, 28 477 specimens of the entomofauna associated with S. pertinax. The families Hydropsychidae, Chironomidae, Bactidae, Simuliidae, Blephariceridae and Megapodagrionidae were represented. These was an impact of temephos on the entomofauna associated with S. pertinax only in Simuliidae and Chironomidae, and to Bti only in Simuliidae. However, the reduction in their numbers was not statistically significant.  相似文献   
16.
Protein patterns were printed using conventional microlithographic materials in a bilayer arrangement and unconventional exposure tools. The bilayer resist stack consisted of a lower poly(tert-butyl methacrylate) layer and an upper diazonaphtoquinone/novolak layer. The protein features were printed in either 'contact printing', or 'step and repeat' mode. The latter printing mode can be managed in a flow-cell consisting of a standard microscope slide and cover slip, spaced apart by about 20 microm, as follows: (i) the exposure step is carried out in the cell using focused 488 nm beam of a confocal laser scanning microscope; (ii) the development step is performed by flowing the photoresist developer through the cell; (iii) the selective deposition of the protein (FITC-labelled avidin) is achieved via the flow of the protein solution through the cell until a desired contrast has been reached; (iv) the control of the process is assured using on-line monitoring of the photo-activated red fluorescence of the developing resist layer, and of the green fluorescence of the FITC-protein patterns, respectively. The protein printing technique uses equipment routinely available in biological laboratory. The 'step and repeat' patterning yields high and controllable resolution. The process can be applied in the fabrication of medical microanalysis devices.  相似文献   
17.
Chaouat M  Levan P  Lalanne B  Buisson T  Nicolau P  Mimoun M 《Plastic and reconstructive surgery》2000,106(7):1614-8; discussion 1619-23
A retrospective study was done on a population of 258 women who had undergone surgery for abdominal dermolipectomy between January of 1991 and May of 1996. The postoperative complications and flaws seen at long-term follow-up are discussed. The surgical techniques used, with or without lipoaspiration, were the infraumbilical plasty and full plasties with horizontal or inverted T scars. Six types of postoperative complications were noted: hemorrhage in 1.2 percent, lymphorrhea in 10.9 percent, infection in 7 percent, skin necrosis in 6.6 percent, secondary dehiscence of the scar in 2.3 percent, and thromboembolic accidents in 1.2 percent. No significant difference was found in the rate of necrosis development between patients who did and did not undergo lipoaspiration. However, a statistically significant difference was seen in the rate of skin necrosis between the T-type plasty (35.5 percent) and the other two procedures (1.43 percent for infraumbilical plasties and 4.60 percent for full plasties with horizontal scar). With regard to the flaws found at long-term follow-up, the rate of above-scar fat folds and/or dog-ears was 27.9 percent, and the rate of defective scars was 26 percent. No significant difference was found with regard to the rate of flaws. The rate of all secondary surgical procedures was 29.1 percent, but performance of secondary procedures depended on the willingness of the patient and on the surgeon's judgment. Abdominoplasty procedures involve a high risk of early complications. The rate of skin necrosis is clearly augmented in cases of T-type plasty. The need for secondary surgical correction is frequent, and the patient should be reminded of this possibility during preoperative consultation.  相似文献   
18.
Transient expression of liposome-encapsulated DNA in liver after intravenous injection to rats and mice has raised questions concerning the intracellular fate of this DNA. Electron microscope autoradiography shows that at 10 min after injection the highest concentration of liposomal DNA which is taken up by the liver is associated with lysosomes and vesicles. The proportion of DNA associated with the mitochondria steadily increases for 1 h after injection, up to 48% of the exogenous DNA found in the tissue. Part of this DNA follows the subcellular fractionation profile of the mitochondrial matrix marker, malate dehydrogenase. In contrast, 14% of the liposomal DNA taken up by the liver is found in the nuclei at 3 min after injection, and this percentage decreases over a period of 1 h. These results permit us to establish the distribution of liposome-encapsulated DNA among subcellular organelles in liver at different times after injection.  相似文献   
19.
Non‐enzymatic glycosylation, a post translational protein modification may be implicated in the diabetes complications. Calmodulin is an important calcium binding protein that complexed with Ca2+ may be implicated in salivary gland secretory process. Glycated calmodulin has shown to be less effective in binding calcium. The aim of this study was to determine whether the concentration of glycated‐calmodulin may be elevated in the submandibular salivary glands of streptozotocin‐induced diabetic rats. Diabetes was induced by an intraperitoneal injection of spreptozotocin, and hyperglycemia was confirmed 72 h after injection using a glucosimeter. Thirty days after the induction of diabetes, submandibular salivary glands were used for the analysis of glycated and non‐glycated calmodulin, using a glycogel B columns for separation. Glycated and non‐glycated calmodulin were assayed by an enzymatic method and by ELISA. The overall concentration of CaM (non‐glycated + glycated) in induced diabetic rats was significantly lower than in controls (p < 0.05). The concentration of non‐glycated CaM in controls was significantly higher than in experimental group (p < 0.05), while the concentration of glycated calmodulin between these groups was statistically similar (p > 0.05). Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
20.

Background

To evaluate the predictive value of carotid atherosclerotic disease (CAD) and intima-media thickness (IMT) on incident cardiovascular disease and mortality in hemodialysis patients.

Methods

Multicenter, observational, prospective study including 110 patients, followed-up to 6 years. Carotid doppler ultrasonographic findings were classified in 4 degrees of severity: 1) IMT <0.9 mm, 2) IMT >0.9 mm, 3) carotid plaque with stenosis <50% and 4) plaque with stenosis >50%. The associations between IMT and CAD and cardiovascular events, total and cardiovascular mortality were assessed.

Results

83% of the patients had atherosclerotic plaques (CAD degrees 3-4). During follow-up, 29.1% of patients experienced cardiovascular events, and 28.2% died, 38.7% of cardiovascular origin. The presence of plaques was associated with cardiovascular events (p = 0.03) while calcified plaques were associated with both cardiovascular events (p = 0.01), cardiovascular mortality (p = 0.03) and non-significantly with overall mortality (p = 0.08) in the survival analysis. Carotid IMT was not associated with outcomes. Cardiovascular events correlated with CAD severity (HR 2.27, 95% CI 1.13-4.54), age (HR 1.04, 1.01-1.06), previous cardiovascular disease (HR 1.75, 1.05-4.42), dyslipidemia (HR 2.25, 1.11-4.53), lipoprotein (a) (HR 1.01, 1.00-1.02), troponin I (HR 3.89, 1.07-14.18), fibrinogen levels (HR 1.38, 0.98-1.94) and antiplatelet therapy (HR 2.14, 1.04-4.4). In an age-adjusted multivariate model, cardiovascular events were independently associated with previous coronary artery disease (HR 3.29, 1.52-7.15) and lipoprotein (a) (HR 1.01, 1.00-1.02).

Conclusions

The presence of carotid plaques and, especially, calcified plaques, are predictors of new cardiovascular events and cardiovascular mortality in hemodialysis patients, while IMT was not. The prognostic value of calcified plaques should be confirmed in future studies.  相似文献   
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