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211.
Human mandible is related to the anatomic skull in several positions among these; centric relation is a significant spatial position. It contributes not only as a reference position to build optimal occlusion in artificial dentition, but is also related to sound periodontal health and stomatognatic function. The purpose of this article is to critically discuss the historical and current definitions of centric relation, the different methods used for recording the same and its clinical implication in the restorative dental practice.  相似文献   
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INTRODUCTION: Population prevalence of chronic obstructive pulmonary disease (COPD) and its relationship with tobacco smoking, environmental tobacco smoke (ETS) exposure and other variables were studied in adult subjects of 35 years and above at four different centres in India. Question-items for the diagnosis of COPD were included in the questionnaire used for the field study on asthma epidemiology. METHODS: Field surveys were conducted in both the urban and the rural populations at Bangalore, Chandigarh, Delhi and Kanpur with the help of a structured and validated questionnaire for diagnosis of asthma and COPD. Separate sets of questions were used for the diagnoses of the two diseases. A two-stage stratified sample design was employed where a village or an urban locality formed the first stage unit and a household formed the second stage unit. A uniform methodology was used at all the four centres and the analyses were done at the central coordinating centre--Chandigarh. Chronic obstructive pulmonary disease, defined by chronic bronchitis (CB) criteria, was diagnosed from the presence of cough and expectoration on most of the days for at least three months in a year for two consecutive years or more. RESULTS: Chronic obstructive pulmonary disease was diagnosed in 4.1% of 35295 subjects, with a male to female ratio of 1.56:1 and a smoker to nonsmoker ratio of 2.65: 1. Prevalence among bidi and cigarette smokers was 8.2% and 5.9%, respectively. Odds ratio (OR) for COPD was higher for men, elderly individuals, lower socio-economic status and urban (or mixed) residence. Environmental tobacco smoke exposure among nonsmokers had an OR of 1.4(95% CI 1.21-1.61). Combined exposure to both ETS and solid fuel combustion had higher OR than for ETS exposure alone. CONCLUSIONS: Population prevalence of COPD is very high in India with some centre to centre differences. Smoking of both bidis and cigarettes, and ETS exposure among nonsmokers, were two important risk factors at all centres. It is important to employ uniform methodology for assessment of national burden and disease-surveillance programme.  相似文献   
214.
Purpose: An unusual complication following severe head trauma in two infants is described.

Method: 'Acute traumatic encephalocele' or 'extracalvarial herniation' is presented as an entity, different from 'growing skull fracture'.

Results: The acuteness of presentation and non-progressive calvarial fracture aperture, along with increasing size of herniated contents is the hall-mark of such pathology.

Conclusion: Repair of dural defect with a patch after excision of gliosed brain provides satisfactory outcome.  相似文献   
215.
CoNS are the major cause of nosocomial infection in last decade and methicillin resistant CoNS has emerged as a major clinical problem. The present study was to compare different phenotypic methods with genotypic method PCR, for the detection of methicillin resistance in CoNS. 100 CoNS isolates from different samples were studied for the detection of mecA gene. PCR was considered as "gold standard". Oxacillin and cefoxitin antibiotics were used for different phenotypic tests (DD, Agar dilution and MHOX). The sensitivities of oxacillin and cefoxitin disks for all CoNS were found to be 92.30% and 88.46% respectively and the specificities were 87.5% and 100% respectively. The sensitivities of the agar dilution test for oxacillin and cefoxitin were 86.53% and 80.76%, respectively, where as the specificities were 79.16% and 85.41%, respectively. The sensitivity of MHOX was observed to be 96.16% and specificity 72.91%. Cefoxitin D.D and oxacillin AD methods could be used as initial test for the determination of methicillin resistance in CoNS isolates. The result of MHOX shows that it could be the best single method for the evaluation of oxacillin resistance mediated by the mecA gene for all CoNS species.  相似文献   
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217.
Relatively few international comparisons of the incidence of influenza related to climate parameters have been performed, particularly in the Eastern hemisphere. In this study, the incidence of influenza and climate data such as temperature, relative humidity, and rainfall, from cities at different latitudes with contrasting climates: Singapore, Hong Kong (China), Ulaanbaatar (Mongolia), Vancouver (Canada), and three Australian cities (Brisbane, Melbourne and Sydney) were examined to determine whether there was any overall relationship between the incidence of influenza and climate. Applying time‐series analyses to the more comprehensive datasets, it was found that relative humidity was associated with the incidence of influenza A in Singapore, Hong Kong, Brisbane, and Vancouver. In the case of influenza B, the mean temperature was the key climate variable associated with the incidence of influenza in Hong Kong, Brisbane, Melbourne, and Vancouver. Rainfall was not significantly correlated with the incidence of influenza A or B in any of these cities. J. Med. Virol. 82:1958–1965, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
218.
The innate immune system protects against infection and tissue injury through the specialized organs of the reticuloendothelial system, including the lungs, liver, and spleen. The central nervous system regulates innate immune responses via the vagus nerve, a mechanism termed the cholinergic antiinflammatory pathway. Vagus nerve stimulation inhibits proinflammatory cytokine production by signaling through the alpha7 nicotinic acetylcholine receptor subunit. Previously, the functional relationship between the cholinergic antiinflammatory pathway and the reticuloendothelial system was unknown. Here we show that vagus nerve stimulation fails to inhibit tumor necrosis factor (TNF) production in splenectomized animals during lethal endotoxemia. Selective lesioning of the common celiac nerve abolishes TNF suppression by vagus nerve stimulation, suggesting that the cholinergic pathway is functionally hard wired to the spleen via this branch of the vagus nerve. Administration of nicotine, an alpha7 agonist that mimics vagus nerve stimulation, increases proinflammatory cytokine production and lethality from polymicrobial sepsis in splenectomized mice, indicating that the spleen is critical to the protective response of the cholinergic pathway. These results reveal a specific, physiological connection between the nervous and innate immune systems that may be exploited through either electrical vagus nerve stimulation or administration of alpha7 agonists to inhibit proinflammatory cytokine production during infection and tissue injury.  相似文献   
219.
CONTEXT: Adolescent hyperandrogenemia is considered a forerunner of adult polycystic ovary syndrome, but its etiology remains uncertain. OBJECTIVE: Our objective was to explore the hypothesis that peripubertal obesity is associated with hyperandrogenemia. DESIGN AND SETTING: We performed a cross-sectional analysis of data obtained at General Clinical Research Centers. SUBJECTS: Subjects were 41 obese [body mass index (BMI) for age, >or=95%] and 35 normal-weight (BMI for age, <95%) peripubertal girls. Intervention: We used pooled blood samples (approximately 0500-0700 h; n = 64) while fasting or single morning (fasting) samples (n = 12). MAIN OUTCOME MEASURES: We assessed adiposity and androgen concentrations. RESULTS: BMI correlated with total testosterone (T) (r(s) = 0.59), SHBG (r(s) = -0.69), and free T (r(s) = 0.69); free T was three times as great in obese girls compared with normal-weight girls (P < 0.0001 for all). BMI correlated with insulin (r(s) = 0.52); both insulin and LH correlated with free T (r(s) = 0.45 and 0.44, respectively; P < 0.001 for all). When analyzing early pubertal girls (pubertal stages 1-3; n = 36) alone, BMI correlated with total T (r(s) = 0.65), SHBG (r(s) = -0.74), and free T (r(s) = 0.75); free T was five times as great in obese early-pubertal girls (P < 0.001 for all). BMI correlated with insulin (r(s) = 0.65), and insulin correlated with free T (r(s) = 0.63, P < 0.01 for both). BMI correlated with free T while simultaneously adjusting for age, pubertal stage, insulin, LH, and dehydroepiandrosterone sulfate. CONCLUSION: Peripubertal obesity is associated with marked hyperandrogenemia, which is especially pronounced in early puberty.  相似文献   
220.
Purpose: Candida colonization in neonates results in significant morbidity and mortality. The purpose of this study was to determine colonization of Candida spp. in preterm babies and identify the risk factors. Methods: Swabs from oral, rectum, groin and umblicus of 103 preterm and 100 term neonates were obtained within 24 hours of birth, day three, day five, day seven and thereafter every week till the neonate was admitted in the neonatal intensive care unit (NICU). Swabs were also collected from the mother’s vagina prior to delivery. Twice every month, air of the NICU was sampled by settle plate and swabs were collected from the hands of health care workers and inanimate objects of NICU. Identification and speciation was done by standard methods. Antibiotic sensitivity was studied against amphotericin B, ketoconazole and fluconazole by disk diffusion method. Results: Colonization with Candida was significantly higher in preterms. Earliest colonization was of oral mucosa and 77.1% of the preterms had colonised at various sites by the first week of life. Significant risk factors in colonized versus non-colonized preterms were male sex, longer duration of rupture of membranes (DROM), administration of steroids and antibiotics and vaginal colonization of mothers, whereas those in preterms versus terms were low birth weight and gestational age. C. albicans was the commonest species, both in the colonized preterms (45.9%) and vagina of mothers. Resistance was seen to fluconazole and ketoconazole only. No Candida spp. was isolated from health care personnel or environment. Conclusions: Colonization of preterms by Candida is a significant problem in NICU and the significant risk factors observed in colonized preterms were male sex, longer DROM, administration of steroids and antibiotics and vaginal colonization of mothers.  相似文献   
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