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991.
Child Psychiatry & Human Development - Recent studies have attempted to measure several biomarkers to understand the complex interactions of the anatomic systems that may be involved in autism...  相似文献   
992.
993.
PURPOSE: The purpose of this study is to propose a doctors' service orientation (DSO) scale and uses it to compare the services received in public, private and foreign hospitals in a developing country from the patient's perspective. DESIGN/METHODOLOGY/APPROACH: The scale was derived from the service quality literature and qualitative research. A questionnaire was designed next. Data were collected from patients who had used the services of doctors in a hospital. FINDINGS: The scale demonstrated appropriate psychometric properties. Two clear patterns emerge from the study results: on 10 out of 12 measures of doctors' service orientation, there was no significant difference in their perceived behaviors between public and private hospitals and foreign doctors were "always" rated significantly higher. RESEARCH LIMITATIONS/IMPLICATIONS: This study focused on one major city because of time and resource constraints. The findings are thus not generalizable to hospitals across the country. Also, because of translation and retranslation issues, the scale ought to be further tested for wider use. ORIGINALITY/VALUE: The scale may be used periodically in a comprehensive quality assurance program to exhort doctors to become more service oriented and to improve their performance over time.  相似文献   
994.
OBJECTIVE: To examine the impact of important weight loss on insulin inhibition of its own secretion during experimentally induced hyperinsulinemia under euglycemic conditions. DESIGN: Longitudinal, clinical intervention study--bariatric surgery (vertical banded gastroplasty--gastric bypass--Capella technique), re-evaluation after 4 and 14 months. SUBJECTS: Nine obese patients class III (BMI=54.6+/-2.6 kg/m2) and nine lean subjects (BMI=22.7+/-0.7 kg/m2). MEASUREMENTS: Euglycemic hyperinsulinemic clamp (insulin infusion: 40 mU/min m2), C-peptide plasma levels, electrical bioimpedance methodology, and oral glucose tolerance test (OGTT). RESULTS: BMI was reduced in the follow-up: 44.5+/-2.2 and 33.9+/-1.5 kg/m2 at 4 and 14 months. Insulin-induced glucose uptake was markedly reduced in obese patients (19.5+/-1.9 micromol/min kg FFM) and improved with weight loss, but in the third study, it was still lower than that observed in controls (35.9+/-4.0 vs 52.9+/-2.2 micromol/min kg FFM). Insulin-induced inhibition of its own secretion was blunted in obese patients (19.9+/-5.7%, relative to fasting values), and completely reversed to values similar to that of lean ones in the second and third studies (-60.8+/-4.2 and -54.0+/-6.1%, respectively).CONCLUSION: Weight loss in severe obesity improved insulin-induced glucose uptake, and completely normalized the insulin inhibition on its own secretion.  相似文献   
995.
An in vitro perfusion biofilm model, derived from tongue-scrape microflora removed from one individual, was employed to study sulfide biogenesis and the effects of repeated exposure to chlorhexidine (CHX). Volatile sulfur compounds (VSC) were measured using a carbon veil electrode within the biofilm and a halimeter for liquid and gas phase levels, respectively. The microflora of the perfusate and the biofilm were assessed by microbiological techniques and polymerase chain reaction (PCR) to estimate diversity. Biofilms treated with a 1 mL pulse of 0.1% CHX twice a day for three days showed (1) a large reduction in viable count (>90% kill), (2) a (slow) reduction in the VSC production rate, consistent with the reduction in microbes rather than direct inhibitory effects on the biotransformation steps, and (3) a preferential reduction of strict anaerobes. Treated biofilms allowed to recover over 3-5 days showed a nominal amount of regrowth in some experiments, although population numbers were still well below those found in untreated controls. The microbiological composition of biofilms treated but allowed to recover was markedly different from the controls, with proportionally fewer strict anaerobes. Thus, CHX treatment caused detectable ecological shifts with consequent long-term effects on the response of the biofilm in terms of VSC generation, consistent with clinical observations. The model appears highly suited for testing the efficacy of putative anti-malodour or antimicrobial agents.  相似文献   
996.
Aim/hypothesis Several epidemiological studies have suggested an association between chronic hyperinsulinaemia and insulin resistance. However, the causality of this relationship remains uncertain.Methods We performed chronic hyperinsulinaemic–euglycaemic clamps and delineated, by western blotting, an IR/IRSs/phosphatidylinositol 3-kinase(PI[3]K)/Akt pathway in insulin-responsive tissues of hyperinsulinaemic rats. IRS-1/2 serine phosphorylation, IR/protein tyrosine phosphatase 1B (PTP1B) association, and mammalian target of rapamycin (mTOR)/p70 ribosomal S6 kinase (p70 S6K) activity were also evaluated in the liver, skeletal muscle and white adipose tissue of hyperinsulinaemic animals.Results We found that chronic hyperinsulinaemic rats have insulin resistance and reduced levels of glycogen content in liver and muscle. In addition, we demonstrated an impairment of the insulin-induced IR/IRSs/PI(3)K/Akt pathway in liver and muscle of chronic hyperinsulinaemic rats that parallels increases in IRS1/2 serine phosphorylation, IR/PTP1B association and mTOR activity. Despite a higher association of IR/PTP1B, there was an increase in white adipose tissue of chronic hyperinsulinaemic rats in IRS-1/2 protein levels, tyrosine phosphorylation and IRSs/PI(3)K association, which led to an increase in basal Akt serine phosphorylation. No increases in IRS-1/2 serine phosphorylation and mTOR activity were observed in white adipose tissue. Rapamycin reversed the insulin resistance and the changes induced by hyperinsulinaemia in the three tissues studied.Conclusions/interpretation Our data provide evidence that chronic hyperinsulinaemia itself, imposed on normal rats, appears to have a dual effect, stimulating insulin signalling in white adipose tissue, whilst decreasing it in liver and muscle. The underlying mechanism of these differential effects may be related to the ability of hyperinsulinaemia to increase mTOR/p70 S6K pathway activity and IRS-1/2 serine phosphorylation in a tissue-specific fashion. In addition, we demonstrated that inhibition of the mTOR pathway with rapamycin can prevent insulin resistance caused by chronic hyperinsulinaemia in liver and muscle. These findings support the hypothesis that defective and tissue-selective insulin action contributes to the insulin resistance observed in hyperinsulinaemic states.  相似文献   
997.
Gastroesophageal reflux disease (GERD) is a condition commonly managed in the primary care setting. Patients with GERD may develop reflux esophagitis as the esophagus repeatedly is exposed to acidic gastric contents. Over time, untreated reflux esophagitis may lead to chronic complications such as esophageal stricture or the development of Barrett's esophagus. Barrett's esophagus is a premalignant metaplastic process that typically involves the distal esophagus. Its presence is suspected by endoscopic evaluation of the esophagus, but the diagnosis is confirmed by histologic analysis of endoscopically biopsied tissue. Risk factors for Barrett's esophagus include GERD, white or Hispanic race, male sex, advancing age, smoking, and obesity. Although Barrett's esophagus rarely progresses to adenocarcinoma, optimal management is a matter of debate. Current treatment guidelines include relieving GERD symptoms with medical or surgical measures (similar to the treatment of GERD that is not associated with Barrett's esophagus) and surveillance endoscopy. Guidelines for surveillance endoscopy have been published; however, no studies have verified that any specific treatment or management strategy has decreased the rate of mortality from adenocarcinoma.  相似文献   
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999.
Rapid diagnosis of Mycobacterium tuberculosis remains an obstacle for therapy of tuberculosis (TB). Adenosine deaminase isoform 2 (ADA2) is produced by activated macrophages and has been used for diagnosis of TB from extra-pulmonary sites. However, few studies adequately address whether serum ADA2 activity is useful for diagnosis of active pulmonary tuberculosis (PTB). We prospectively measured serum ADA2 activity in 110 patients with pulmonary disease (65 cases with active PTB and 45 cases with other respiratory diseases) and 78 healthy volunteers (eight with tuberculin skin test positive). The serum ADA2 for the diagnosis of PTB had the sensitivity of 36.9%, the specificity of 84.5%, the positive predictive value of 10.9% and the negative predictive value of 96.2%. We concluded that serum ADA2 activity is neither useful to diagnosis of active PTB nor to differentiate from other respiratory diseases.  相似文献   
1000.
New information was collected on cystic echinococcosis in livestock (camels, cattle and sheep) and humans in the central region of Sudan. The livestock data were collected in abattoir-based surveys in the towns of Omdurman, Tamboul and Wad Madani, between 1998 and 2001, and covered a total of 8205 animals. The highest prevalence of infection was found in the camels (44.6% of 242 infected), followed by the sheep (6.9% of 5595) and cattle (3.0% of 2368). Records were made of the sizes of the 1320 hydatid cysts detected in the livestock (907 in sheep, 71 in cattle, and 342 in camels), whether or not each cyst was fertile, and where it occurred in the body of the host. Cysts collected from cattle and camels where much more likely to be fertile (22% and 24%, respectively) than those from sheep (1%). Camels and cattle therefore appear to be the principal intermediate hosts for Echinococcus granulosus in central Sudan, whereas sheep apparently play a marginal role in transmission. In 2002, as a preliminary assessment of the public-health impact of the disease, 300 residents of a rural village 60 km west of Wad Madani were surveyed using a portable ultrasound scanner. Only one (0.33%) of the villagers investigated was found infected. The implications of these finding are discussed in terms of the various strains of E. granulosus and the role of each in human disease.  相似文献   
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