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101.
Intragastric glucose inhibits gastric acid secretion and gastric emptying in man. To determine if these effects are mediated by somatostatin—a known inhibitor of gastric acid production, gastrin secretion, and gastric motility—the plasma somatostatin-like immunoreactivity (SLI) levels were determined in healthy human subjects after an intragastric load of 30% glucose solution. These findings were compared with results after an instillation of distilled water. Following the glucose load, the intragastric acid concentration, the acid output, and the fractional gastric emptying rate declined significantly (P<0.01) before either the plasma glucose or plasma insulin levels had increased. Neither the gastrin nor SLI plasma concentrations changed after the water or glucose load. These findings suggest that the suppression of gastric acid secretion and inhibition of the rate of gastric emptying that occur with intragastric glucose are mediated by factors other than changes in the peripheral circulating levels of SLI, gastrin, insulin, or glucose.  相似文献   
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103.
The European Study Group on diastolic heart failure requires objective evidence of abnormal left ventricular diastolic function to establish the diagnosis of diastolic heart failure, which is common in older people. Reference values for Doppler indices of transmitral flow, used to assess left ventricular diastolic function, have not been reported for people 70 years and over in Europe. The aim of this study was to establish reference values for these Doppler indices of transmitral flow in older people. A random sample of 355 subjects aged 70 and over, living in the community underwent clinical assessment and echocardiography. Asymptomatic subjects with no cardiovascular disease and cardiovascular risk factors were identified. Measurements of five commonly used Doppler indices of transmitral flow from these subjects were obtained and reference range expressed as mean+/-2 standard deviations and as percentiles. We have therefore generated reference Doppler values of transmitral flow for people aged over 70 in a British population.  相似文献   
104.
Haemodialysis patients are known to be at risk of infection of Hepatitis C Virus (HCV) through nosocomial spread. This paper presents the first part of a study on epidemiology and management of HCV, in a haemodialysis population, conducted by the EDTNA/ERCA Research Board. Data on HCV management and infection control procedures was collected from 136 European centres using an electronic questionnaire. The study identifies a number of possible risk factors for transmission of the virus: failing to disinfect devices between patients, sharing of single-use vials to prepare drugs or infusions for different patients, inadequate sterilisation or cleaning of machines between dialysis sessions, unsatisfactory environmental cleaning and distance less than one metre between chairs.  相似文献   
105.
106.
Laccase-mediated oligomerisation of 4-hydroxybenzoic acid (4-HBA) derivatives and simultaneous in situ surface modification has proven to be a cost-effective, easily applicable and eco-friendly strategy for preventing biofouling of poly(ethersulfone) (PES) water filtration membranes. Modification of the membrane surface has previously been hypothesised to occur through covalent bonding of enzymatically generated phenolic radicals to the polymeric membrane. The current study shows, however, that in situ formation of soluble phenolic oligomers does not result in covalent membrane modification. We studied in situ laccase-mediated oligomerisation of custom-synthesised positively charged and commercially available negatively charged monomeric phenols, and demonstrated that their mode of binding to PES is not covalent. In addition, soluble, non-soluble and on-resin PES model compounds were synthesised and used in the laccase-mediated oligomerisation of 4-HBA. Covalent bond formation between these model compounds and (oligomeric) 4-HBA could not be observed either. Furthermore, extensive washing of PES membranes modified through laccase-mediated oligomerisation of 4-HBA resulted in substantial discolouration of the membrane surface, showing that the layer of oligomerised phenolics could easily be removed. Altogether, it was concluded that laccase-assisted modification of PES membranes resulted from strong physical adsorption of phenolic oligomers and polymers rather than from covalent bonding of those.

The mechanism behind the laccase-mediated functionalisation of poly(ethersulfone) was studied using a multifaceted approach, which revealed that surface modification had occurred through strong physical adsorption, rather than through grafting of phenolic oligomers.  相似文献   
107.

Objective

Poor prognosis is difficult to impart, particularly across a cultural divide. This study compared prognostic communication with immigrants (with and without interpreters) versus native-born patients in audio-taped oncology consultations.

Methods

Ten oncologists, 78 patients (31 Australian-born, 47 immigrants) and 115 family members participated. The first two consultations after diagnosis of incurable disease were audiotaped, transcribed and coded. 142 consultations were included in the analysis.

Results

Fifty percent of doctor and 59% of patient prognostic speech units were not interpreted or interpreted non-equivalently when an interpreter was present. Immigrant status predicted few prognostic facts, and oncologist characteristics no prognostic facts, disclosed. Oncologists were significantly less likely to convey hope to immigrants (p = 0.0004), and more likely to use medical jargon (p = 0.009) than with Australian-born patients. Incurable disease status and a limited life span were commonly acknowledged, generally with no timeframe provided. Physical issues were discussed more commonly than emotional aspects.

Conclusions

While culture did not appear to influence doctor speech, interpreters filtered or blocked much prognostic communication.

Practice implications

Initiatives to empower all patients to attain needed information, optimise communication when an interpreter is present and train cancer health professionals in culturally appropriate care, are urgently required.  相似文献   
108.
109.
110.
Treacher Collins Syndrome (TCS) is the most common of the human mandibulofacial dysostosis disorders. Recently, a partial TCOF1 cDNA was identified and shown to contain mutations in TCS families. Here we present the entire exon/intron genomic structure and the complete coding sequence of TCOF1. TCOF1 encodes a low complexity protein of 1,411 amino acids, whose predicted protein structure reveals repeated motifs that mirror the organization of its exons. These motifs are shared with nucleolar trafficking proteins in other species and are predicted to be highly phosphorylated by casein kinase. Consistent with this, the full-length TCOF1 protein sequence also contains putative nuclear and nucleolar localization signals. Throughout the open reading frame, we detected an additional eight mutations in TCS families and several polymorphisms. We postulate that TCS results from defects in a nucleolar trafficking protein that is critically required during human craniofacial development.  相似文献   
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