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21.
The University of Oklahoma Medical Center has a comprehensive program of pediatric training, research and patient care. Establishment of the Oklahoma Health Center and its Children's Medical Center on the University campus will provide expanded opportunities for training and research in cooperation with other organizations concerned with child health and development.  相似文献   
22.
We studied the interaction between paracetamol (acetaminophenU.S.P.) and enflurane. Sixteen rats were assigned to four groups(n=4) to receive: paracetamol 7.5 mg/100 g body weight; paracetamolplus 1% enflurane; 1% enflurane alone, or no treatment (controls).Animals were killed 6 h later. A second series of 16 were treatedidentically, but were killed after 24 h. Measurements were madeof fluoride concentrations in serum, liver and urine (indicatorsof biotransformation of enflurane), paracetamol concentrationsin urine, pathological changes in liver samples, and concentrationsof the enzymes aspartate aminotransferase (AST) and alanineaminotransferase (ALT) in serum. Pretreatment with paracetamolsignificantly decreased urinary fluoride at 6 and 24 h afterexposure to enflurane, but decreased fluoride concentrationsin serum and liver only at 6 h after exposure to enflurane.Paracetamol concentrations in urine did not change after exposureto enflurane. Exposure to paracetamol alone increased AST andALT. At 24 h after exposure to enflurane, serum concentrationsof enzymes in rats pretreated with paracetamol were similarto those of control rats. Pretreatment with paracetamol maytherefore inhibit metabolism of enflurane. Although no hepaticdamage was observed, the increased in AST and AL T suggestedsubclinical liver damage in rats given only paracetamol.  相似文献   
23.
24.
The ramification of the portal vein at the porta hepatis was studied by anatomic dissection performed in 32 formalin fixed human livers. In all the specimens there were branches which ran towards the caudate lobe, arising from the portal vein and either from the left or the right portal branches. Tri-and quadrifurcation of the portal vein was observed. In 5 cases (16%) there were branches arising from left portal branch or portal vein and directed anteriorly to the quadrate lobe or to the region of the gall-bladder sulcus. These branches ranged from 1.0 to 6.0 mm in diameter. The portal caudate branches were divided into 3 groups.Group 1: Branches to the papillary process; 1 or 2 branches in 26 cases (82%), 3 or 5 branches in 3 cases (9%) and no branches in 3 cases (9%);  相似文献   
25.
Using mechanical and chemical dissection methods, fibrous sheath was isolated both from normal ejaculated human spermatozoa and from rabbit cauda epididymal spermatozoa. The same techniques did not produce a pure preparation of fibrous sheath from ejaculated rabbit spermatozoa, suggesting that further cross-linking and stabilization of sperm structures occurs in response to components of the seminal plasma. The isolation procedures were monitored by phase contrast microscopy and the purity of the fibrous sheath was verified by electron microscopy. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) of isolated human fibrous sheath revealed at least 14 protein bands of which the most intensely stained were of molecular weight 84, 72, 66.2, 57, 32 and 28.5 kDa. The rabbit fibrous sheath revealed at least 10 protein bands, of which the most intensely stained were 35.2, 32.7 and 28.5 kDa. The amino acid composition of the purified fibrous sheath from human and rabbit spermatozoa was similar, being high in aspartic acid and/or asparagine and glutamic acid and/or glutamine, serine, alanine, leucine, lysine and glycine, but low in histidine, tyrosine and isoleucine. This composition is similar to that reported for the rat and suggests that mammalian sperm tail fibrous sheaths are composed of similar types of proteins, although there are apparent differences in protein components between species.   相似文献   
26.
High salt (sodium chloride) consumption is an important determinant of high blood pressure and cardiovascular risk. According to World Health Organisation (WHO) statistics, over 80% of cardiovascular disease (CVD) deaths take place in low-and middle-income countries, and elevated blood pressure levels were a major cause of these CVD deaths in those countries.1 Lifestyle factors such as unhealthy diet, physical inactivity, tobacco use and harmful use of alcohol have been considered the most important behavioural risk factors for heart disease and stroke.2Among dietary factors, high salt intake has been the most strongly associated with raised blood pressure and increased risk of stroke and CVD.3 Therefore dietary sodium restriction has been recommended as a non-pharmacological approach to blood pressure lowering,4-6 and for the prevention and control of non-communicable diseases at the population level.7,8Cumulative evidence has shown that even a modest reduction in salt intake was associated with blood pressure lowering and therefore with a significant reduction in incidence of cardiovascular events.9-12 Furthermore, data from the most recent systematic review and meta-analyses has shown the benefit of lowering sodium intake in apparently healthy adults and children,13 and in both hypertensive and normotensive individuals, irrespective of gender and ethnic group.9Since hypertension is associated with CVD worldwide, a public health intervention to reduce high blood pressure must target the role of lifestyle, particularly reduced sodium intake.7 Therefore, several countries have initiated strategies to reduce dietary salt intake in the general population by a combination of various procedures such as public education, food labelling, and collaboration with the food industry to reduce the salt content of processed food.14Among sub-Saharan African countries, only Nigeria and South Africa have developed dietary guidelines regarding salt intake.15 Recently, the South African government implemented important specific legislation towards decreasing salt intake in the population by reducing sodium content of processed foods by industries.16 Therefore, the current public health recommendation is that countries should launch national initiatives to reduce the over-consumption of salt as part of non-communicable disease prevention and healthy nutrition policies for limiting salt intake to less than 5 g/day for the general population including children.7 Despite of this guideline, however, high sodium intake remains prevalent around the world, with average daily salt intake varying from 5 to 18 g/day per person.17Although processed foods have been found to be the principal source of excessive dietary salt intake,18 sources of dietary sodium vary largely worldwide and may be influenced by cultural context and dietary habits of the population.19 In sub-Saharan African countries experiencing demographic and epidemiological transition, the rapid rise in prevalence of CVD (chiefly hypertension) has been attributed to lifestyle change, including high dietary sodium intake.20,21 However, consistent data from studies on risk factors are lacking for the majority of these countries.With regard to Angola, available data from a cross-sectional study reported a high prevalence of multiple cardiovascular risk factors, such as hypertension, sedentary lifestyle, electrocardiographic left ventricular hypertrophy,22 and high rate of the metabolic syndrome23 in an apparently healthy middle-aged population of university public employees living in urban and peri-urban areas.Determining the level of sodium intake in the population is crucial to establish intervention strategies and policy on reduction of sodium intake. For medical students in particular, it is very important to assess their awareness regarding dietary salt intake, since they are the future providers of healthcare information for the counselling of people about the need to reduce salt consumption. The aim of this study was to determine salt intake and to assess the knowledge, attitude and behaviour regarding dietary salt among medical students.  相似文献   
27.
Many of the current procedures for detecting coding regions on human DNA sequences combine a number of individual techniques such as discriminant analysis and neural net methods. Recent papers have used techniques from nonlinear systems identification, in particular, parallel cascade identification (PCI), as one means for classifying protein sequences into their structure/function groups. In the present paper, PCI is used in a pilot study to distinguish exon (coding) from intron (noncoding; interspersed within genes) human DNA sequences. Only the first exon and first intron sequences with known boundaries in genomic DNA from the T-cell receptor locus were used for training. Then, the parallel cascade classifiers were able to achieve classification rates of about 89% on novel sequences in a test set, and averaged about 82% when results of a blind test were included. In testing over a much wider range of human nucleotide sequences, PCI classifiers averaged 83.6% correct classifications. These results indicate that parallel cascade classifiers may be useful components in future coding region detection programs. © 2002 Biomedical Engineering Society. PAC2002: 8715Cc, 8714Gg, 8715Aa  相似文献   
28.
    

Objectives

The aim of the study was to evaluate the long‐term response to antiretroviral treatment (ART) based on atazanavir/ritonavir (ATZ/r)‐, darunavir/ritonavir (DRV/r)‐, and lopinavir/ritonavir (LPV/r)‐containing regimens.

Methods

Data were analysed for 5678 EuroSIDA‐enrolled patients starting a DRV/r‐, ATZ/r‐ or LPV/r‐containing regimen between 1 January 2000 and 30 June 2013. Separate analyses were performed for the following subgroups of patients: (1) ART‐naïve subjects (8%) at ritonavir‐boosted protease inhibitor (PI/r) initiation; (2) ART‐experienced individuals (44%) initiating the new PI/r with a viral load (VL) ≤500 HIV‐1 RNA copies/mL; and (3) ART‐experienced patients (48%) initiating the new PI/r with a VL >500 copies/mL. Virological failure (VF) was defined as two consecutive VL measurements >200 copies/mL ≥24 weeks after PI/r initiation. Kaplan–Meier and multivariable Cox models were used to compare risks of failure by PI/r‐based regimen. The main analysis was performed with intention‐to‐treat (ITT) ignoring treatment switches.

Results

The time to VF favoured DRV/r over ATZ/r, and both were superior to LPV/r (log‐rank test; P < 0.02) in all analyses. Nevertheless, the risk of VF in ART‐naïve patients was similar regardless of the PI/r initiated after controlling for potential confounders. The risk of VF in both treatment‐experienced groups was lower for DRV/r than for ATZ/r, which, in turn, was lower than for LPV/r‐based ART.

Conclusions

Although confounding by indication and calendar year cannot be completely ruled out, in ART‐experienced subjects the long‐term effectiveness of DRV/r‐containing regimens appears to be greater than that of ATZ/r and LPV/r.
  相似文献   
29.

Introduction

Continuous renal replacement therapy (CRRT) is a widely used but resource-intensive treatment. Despite its broad adoption in intensive care units (ICUs), it remains challenging to identify patients who would be most likely to achieve positive outcomes with this therapy and to provide realistic prognostic information to patients and families.

Methods

We analyzed a prospective cohort of all 863 ICU patients initiated on CRRT at an academic medical center from 2008 to 2011 with either new-onset acute kidney injury (AKI) or pre-admission end-stage renal disease (ESRD). We examined in-hospital and post-discharge mortality (for all patients), as well as renal recovery (for AKI patients). We identified prognostic factors for both in-hospital and post-discharge mortality separately in patients with AKI or ESRD.

Results

In-hospital mortality was 61% for AKI and 54% for ESRD. In patients with AKI (n = 725), independent risk factors for mortality included age over 60 (OR 1.9, 95% CI 1.3, 2.7), serum lactate over 4 mmol/L (OR 2.2, 95% CI 1.5, 3.1), serum creatinine over 3 mg/dL at time of CRRT initiation (OR 0.63, 95% CI 0.43, 0.92) and comorbid liver disease (OR 1.75, 95% CI 1.1, 2.9). Among patients with ESRD (n = 138), liver disease was associated with increased mortality (OR 3.4, 95% CI 1.1, 11.1) as was admission to a medical (vs surgical) ICU (OR 2.2, 95% CI 1.1, 4.7). Following discharge, advanced age became a predictor of mortality in both groups (AKI: HR 1.9, 95% CI 1.2, 3.0; ESRD: HR 4.1, 95% CI 1.5, 10.9). At the end of the study period, only 25% (n = 183) of patients with AKI achieved dialysis-free survival.

Conclusions

Among patients initiating CRRT, risk factors for mortality differ between patients with underlying ESRD or newly acquired AKI. Long-term dialysis-free survival in AKI is low. Providers should consider these factors when assessing prognosis or appropriateness of CRRT.  相似文献   
30.
Seventeen isolates of Borrelia burgdorferi sensu lato with an unclear genetic characteristic isolated in Russia from various species of Ixodes ticks (I. persulcatus, I. ricinus, and I. pavlovskyi) have been studied by multilocus sequencing analysis. According to the results of typing, these isolates were identified as B. bavariensis (n = 7), B. garinii (n = 6), B. finlandensis (n = 3), and B. spielmanii (n = 1), that is, species that can cause ixodid tick-borne borreliosis diseases in human beings. The allelic polymorphism of five genes (rrs, fla, groEL, recA, and ospA) and spacer rrfArrlB of B. bavariensis and B. garinii isolates was analyzed in comparison with their diversity in the International Nucleotide Sequence Database Collaboration.  相似文献   
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