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51.
The present study was conducted to compare the effect of naloxone, an opiate receptor antagonist, with catecholamines on acid-base status and survival in dogs subjected to hemorrhagic shock. Arterial lactic acid concentration which had increased during hemorrhage, decreased significantly (P less than 0.05) in naloxone treated animals but increased further in catecholamine treated dogs. Blood bicarbonate concentration and PCO2 which had markedly decreased 1 hr after hemorrhage recovered significantly (P less than 0.05) in naloxone group of animals. On the other hand bicarbonate and pH declined further in noradrenaline group and remained unchanged in dopamine group. These results as well as better survival rate observed in naloxone treated animals suggest the superiority of naloxone over dopamine and noradrenaline, as an adjunct to blood transfusion in the treatment of hemorrhagic shock.  相似文献   
52.
Expression of the insulin-like growth factor-binding protein 5 (IGFBP-5) gene in vascular smooth muscle cells is up-regulated by IGF-I through an IGF-I receptor-mediated mechanism. In this study, we studied the possible involvement of the mitogen-activated protein kinase (MAPK) and PI 3-kinase signaling pathways in mediating IGF-I-regulated IGFBP-5 gene expression. The addition of Des(1-3)IGF-I, an IGF analog with reduced affinity to IGFBPs, resulted in a transient activation of p44 and p42 MAPK. Inhibition of the MAPK activation by PD98059, however, did not affect IGF-I-stimulated IGFBP-5 expression. Des(1-3)IGF-I treatment also strongly activated PI 3-kinase. This activation was probably mediated through IRS-1, because IGF-I stimulation resulted in a significant increase in IRS-1- but not IRS-2-associated PI 3-kinase activity. This activation occurred within 5 min and was sustained at high levels for over 6 h. Likewise, Des(1-3)IGF-I caused a long lasting activation of PKB/Akt and p70(s6k). When LY294002 and wortmannin, two specific inhibitors of PI 3-kinase, were added with Des(1-3)IGF-I, the IGF-I-regulated IGFBP-5 expression was negated. The addition of rapamycin, which inhibits IGF-I-induced p70(s6k) activation, significantly inhibited IGF-I-regulated IGFBP-5 gene expression. These results suggest that the action of IGF-I on IGFBP-5 gene expression requires the activation of the PI 3-kinase-PKB/Akt-p70(s6k) pathway but not the MAPK pathway in vascular smooth muscle cells.  相似文献   
53.
54.

Background

Mortality prediction models generally require clinical data or are derived from information coded at discharge, limiting adjustment for presenting severity of illness in observational studies using administrative data.

Objectives

To develop and validate a mortality prediction model using administrative data available in the first 2 hospital days.

Research Design

After dividing the dataset into derivation and validation sets, we created a hierarchical generalized linear mortality model that included patient demographics, comorbidities, medications, therapies, and diagnostic tests administered in the first 2 hospital days. We then applied the model to the validation set.

Subjects

Patients aged ≥18 years admitted with pneumonia between July 2007 and June 2010 to 347 hospitals in Premier, Inc.’s Perspective database.

Measures

In hospital mortality.

Results

The derivation cohort included 200,870 patients and the validation cohort had 50,037. Mortality was 7.2%. In the multivariable model, 3 demographic factors, 25 comorbidities, 41 medications, 7 diagnostic tests, and 9 treatments were associated with mortality. Factors that were most strongly associated with mortality included receipt of vasopressors, non-invasive ventilation, and bicarbonate. The model had a c-statistic of 0.85 in both cohorts. In the validation cohort, deciles of predicted risk ranged from 0.3% to 34.3% with observed risk over the same deciles from 0.1% to 33.7%.

Conclusions

A mortality model based on detailed administrative data available in the first 2 hospital days had good discrimination and calibration. The model compares favorably to clinically based prediction models and may be useful in observational studies when clinical data are not available.  相似文献   
55.

Background

Peer influence and social networking can change female adolescent and young adult behavior. Peer influence on preferences for male human papillomavirus (HPV) vaccination has not been documented. The primary aim of this study was to determine if women had preferences about male sexual partner HPV vaccination receipt.

Methods and Findings

A prospective survey of women 18–26 years of age was conducted at an urban university student health clinic. Education about the two HPV vaccines, cervical cancer and genital warts was provided. Women self-reported their demographic and medical history data, as well as their own preferences for HPV vaccine and their preferences for their male partner HPV vaccine using a 5 point Likert scale. 601 women, mean age of 21.5 years (SD 2.4), participated between 2011 and 2012. Nearly 95% of respondents were heterosexual; condoms and contraceptives were used in over half of the population. Regardless of the woman''s vaccination status, women had significantly higher (strongly agree/agree) preferences for the male partner being vaccinated with HPV4 than not caring if he was vaccinated (63.6% vs. 13.1%, p<0.001). This preference was repeated for sexual risk factors and past reproductive medical history. Women who received HPV4 compared to those choosing HPV2 had a significantly lower proportion of preferences for not caring if the male partner was vaccinated (13% vs. 22%, p = 0.015).

Conclusions

Women preferred a HPV vaccinated male partner. Peer messaging might change the male HPV vaccination uptake.  相似文献   
56.
The World Health Organization has called for an effort to eliminate Lymphatic Filariasis (LF) around the world. In regions where the disease is endemic, local production and distribution of medicated salt dosed with diethylcarbamazine (DEC) has been an effective method for eradicating LF. A partner of the Notre Dame Haiti program, Group SPES in Port-au-Prince, Haiti, produces a medicated salt called Bon Sel. Coarse salt is pre-washed and sprayed with a solution of DEC citrate and potassium iodate. Iodine levels are routinely monitored on site by a titrimetric method. However, the factory had no method for monitoring DEC. Critical analytical issues include 1) determining whether the amount of DEC in each lot of Bon Sel is within safe and therapeutically useful limits, 2) monitoring variability within and between production runs, and 3) determining the effect of a common local practice (washing salt before use) on the availability of DEC. This paper describes a novel titrimetric method for analysis of DEC citrate in medicated salt. The analysis needs no electrical power and requires only a balance, volumetric glassware, and burets that most salt production programs have on hand for monitoring iodine levels. The staff of the factory used this analysis method on site to detect underloading of DEC on the salt by their sprayer and to test a process change that fixed the problem.  相似文献   
57.
Nonalcoholic fatty liver disease (NAFLD) is associated with obesity and insulin resistance. It is also a predisposing factor for type 2 diabetes. Dietary factors are believed to contribute to all three diseases. NAFLD is characterized by increased intrahepatic fat and mitochondrial dysfunction, and its etiology may be attributed to excessive fructose intake. Consumption of high fructose corn syrup‐55 (HFCS‐55) stands at up to 15% of the average total daily energy intake in the United States, and is linked to weight gain and obesity. The aim of this study was to establish whether HFCS‐55 could contribute to the pathogenesis of NAFLD, by examining the effects of HFCS‐55 on hepatocyte lipogenesis, insulin signaling, and cellular function, in vitro and in vivo. Exposure of hepatocytes to HFCS‐55 caused a significant increase in hepatocellular triglyceride (TG) and lipogenic proteins. Basal production of reactive oxygen metabolite (ROM) was increased, together with a decreased capacity to respond to an oxidative challenge. HFCS‐55 induced a downregulation of the insulin signaling pathway, as indicated by attenuated ser473phosphorylation of AKT1. The c‐Jun amino‐terminal kinase (JNK), which is intimately linked to insulin resistance, was also activated; and this was accompanied by an increase in endoplasmic reticulum (ER) stress and intracellular free calcium perturbation. Hepatocytes exposed to HFCS‐55 exhibited mitochondrial dysfunction and released cytochrome C (CytC) into the cytosol. Hepatic steatosis and mitochondrial disruption was induced in vivo by a diet enriched with 20% HFCS 55; accompanied by hypoadiponectinemia and elevated fasting serum insulin and retinol‐binding protein‐4 (RBP4) levels. Taken together our findings indicate a potential mechanism by which HFCS‐55 may contribute to the pathogenesis of NAFLD.  相似文献   
58.
A recombinant glycosylated avidin (recGAvi) with an acidic isoelectric point was expressed and secreted by the methylotrophic yeast Pichia pastoris. The coding sequence for recGAvi was de novo synthesized based on the codon usage of P. pastoris. RecGAvi is secreted at approximately 330mg/L of culture supernatant. RecGAvi monomer displays a molecular weight of 16.5kDa, as assessed by ESI mass spectrometry. N-terminal amino acid sequencing indicates the presence of three additional amino acids (E-A-E), which contribute to further lowering the isoelectric point to 5.4. The data presented here demonstrate that the P. pastoris system is suitable for the production of recGAvi and that the recombinant avidin displays biotin-binding properties similar to those of the hen-egg white protein.  相似文献   
59.
C-banding and Ag staining were applied to Cacopsylla sorbi and C. mali. The aim was to discover some additional cytological markers to follow the pathways of the sex determination system transformation in the evolution of the species. Of three karyotype patterns so far described in the literature for these species--a type A (XO), B (neoXY) and C (neoX1X2Y), only the last two types (B and C) were found. All 6 studied Cacopsylla sorbi from Finland had a karyotype of type B (2n = 20 + XY), while C. mali had both types. Type B (2n = 22 + XY) was observed in 31 males, whereas type C (2n = 20 + neoX1X2Y) in the remaining four. The karyotype of C. sorbi was found to be characterized by a very small amount of C-positive material, localized in a telomere of the Y chromosome. The karyotype of C. mali was also characterized by a very small amount of C-banded material. Both the sex chromosomes and the autosomes displayed a marked polymorphism of C-positive bands within different individuals and even the same individual. In both species the nucleolus was located in the telomere of a middle sized autosomal till diplotene inclusive. The C-banding and Ag staining in the studied Cacopsylla species did not provide any additional cytological markers for an understanding of the pathways of sex determination system transformation in the evolution of the species.  相似文献   
60.
Karyotypes of males of cicadas Tibicen bihamatus (Motschulski) and Platypleura kuroiwae Matsumura were studied using C-banding technique. In Tibicen bihamatus two types of C-band distribution were observed. Two chromosome pairs have C-bands at one of the chromosome ends, while in the other, including the sex chromosome, C-heterochromatin blocks occurred at both ends. Platypleura kuroiwae has a smaller amount of C-heterochromatin located as small subterminal blocks. The intercalar C-bands were seen in the early spermatogonial metaphase chromosomes.  相似文献   
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