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51.
It is postulated that a vigorous host inflammatory response in the cystic fibrosis lung contributes to lung injury. Tumour necrosis factor-alpha (TNF-alpha) may play a part in that process and in the generation of leukotrienes. Therefore, the relationships between sputum TNF-alpha, leukotriene concentration, and lung function abnormalities in 16 children with cystic fibrosis were investigated. Each subject provided sputum samples and performed spirometry. TNF-alpha was measured by enzyme linked immunosorbent assay; individual leukotrienes were separated using high performance liquid chromatography and quantified by radioimmunoassay. The geometric mean concentration of TNF-alpha was 129.7 pg/ml and 95% confidence interval 48.2 to 348.3. Mean (SEM) leukotriene B4 (LTB4) was 97.8 (22.9) pmol/g and total cysteinyl leukotrienes were 60.9 (14.8) pmol/g. Mean (SD) forced expiratory volume in one second (FEV1) of the group was 53 (15)% of predicted and forced vital capacity (FVC) was 65 (14)% of predicted. There was a significant positive correlation between TNF-alpha and both LTB4 and the total cysteinyl leukotriene sputum content. An inverse relationship existed between TNF-alpha and FEV1 and FVC. Moreover, a negative correlation was observed between sputum LTB4 and FEV1 and FVC. These results suggest that TNF-alpha and the leukotrienes may participate in the airways inflammation and airflow obstruction observed in cystic fibrosis subjects and support the hypothesis that TNF-alpha upregulates the 5-lipoxygenase pathway in vivo.  相似文献   
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A postal survey of recently appointed consultant paediatricians was undertaken to determine whether they perceived their training had adequately equipped them for their current job. The response rate was 69% (207/299). After excluding replies from consultants trained outside the UK the analysis was carried out on 167 replies. Trainees held a mean 5.2 posts during general and higher professional training, necessitating a mean 1.8 house moves. Altogether 82% felt moves were beneficial to training but 46% found moves 'very disruptive' to family life. Only 12% of district general hospital and 22% of teaching hospital senior registrars took two research sessions a week. Supervision and training in research was absent or poor for more than 60%; 24% felt major changes and 55% moderate changes were needed to current training. Training in non-clinical skills was particularly in demand and a curriculum for both trainers and trainees with regular appraisals is required. Research at senior registrar level needs review and educational methods improved to achieve better training in a shorter period.  相似文献   
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Sequential recordings were made in the first five months after birth of metabolic rate, environmental temperature, and body temperature during sleep at home in 17 infants, each with an older sibling. Further recordings were made whenever an older sibling developed an upper respiratory tract infection (URTI), again four to six days later, and again two weeks later, aiming to achieve recordings before, during, and after an URTI in the infant. The temperature of the room and wrapping of the infant were determined according to their usual practice by the parents. Parents added appropriate wrapping to achieve thermal neutrality based on our calculated values and the measured oxygen consumption. In five of the six infants who developed an URTI in the first three months after birth there was no change or a decrease in metabolic rate at the time of the infection; for infants older than 3 months the metabolic rate increased in three of the five episodes recorded. Peripheral skin temperature decreased at the time of URTI at all ages, though in the older infants it usually increased in parallel with rectal temperature during the latter part of the night, when pyrexia was most common. Infants thus respond to URTI by heat conservation. In the younger infants the lower metabolic rate and the further decrease in this rate with URTI means that fever is rare, and their temperature may decrease on infection. In the older infants the increase in metabolic rate (from an already higher baseline) may result in fever. These differences may contribute to the increased vulnerability of the older infants to heat stress, particularly at the time of acute viral infections.  相似文献   
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Objective : To describe the obstetric and perinatal factors, in particular the method of delivery, associated with development of a subgaleal haematoma (SGH) and to determine the outcome of survivors with this type of birth trauma. Methodology : Perinatal and obstetric data were retrospectively reviewed for 37 infants admitted to the neonatal unit of the sole tertiary paediatric referral hospital in Western Australia with an SGH, over a 24 year period from 1970 to 1993. These data were compared to data for all Western Australian births. The long-term outcome was obtained through medical and private paediatric records for 26 of these infants. Results : All except one of the neonates had instrumental deliveries; 89% had a vacuum extractor applied to the head at some stage of delivery compared to 10% of the general population of births in Western Australia. There was also a significantly increased risk of failure of attempted vacuum extraction. Of the cases where a vacuum extraction was attempted, 45% also had forceps applied to the head. Coagulopathy was associated with the severity of the SGH. There was also a high frequency of occurrence (40%) of associated head trauma such as intracranial haemorrhage, skull fracture and cerebral oedema, as well as neonatal encephalopathy (73%). The occurrence of these associated features did not correlate significantly with the severity of SGH. Minor complications of SGH included jaundice and facial bruising. There was an excess mortality associated with SGH; however, the long-term outcome for neonatal survivors with this disorder was good. None of the cases studied subsequently developed cerebral palsy or intellectual disability, and minor neurological sequelae only were documented in four infants. Conclusions : SGH is an uncommon type of birth trauma, and is associated with delivery or attempted delivery by vacuum extraction. The most commonly associated clinical problems were hypovolaemia and coagulopathy. The long-term outcome for neonates with this condition is good.  相似文献   
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OBJECTIVES: To determine independent relationships between age and the risk of in-hospital death. DESIGN: Retrospective cohort study. SETTING: Thirty-eight intensive care units (ICUs) in 28 hospitals in a large Midwest metropolitan region. PARTICIPANTS: One hundred fifty-six thousand, one hundred thirty-six consecutive admissions to medical, surgical, neurological, and mixed medical/surgical ICUs between March 1, 1991, and March 31, 1997. MEASUREMENTS: In-hospital death rates were compared at successive 5-year age intervals, adjusting for gender, diagnosis, admission source, comorbidity, and acute physiology scores. Acute physiology scores were determined using a validated methodology based on abnormalities in 17 physiological measures collected during the first 24 hours of ICU admission. RESULTS: The adjusted odds of death increased with each 5-year age increment. For example, relative to patients younger than 35, adjusted odds of death in patients aged 40 to 44, 50 to 54, 60 to 64, 70 to 74, 80 to 84, and 90 and older were 1.51, 1.73, 2.38, 2.98, 3.86, and 4.74, respectively. In stratified analyses, age-related increases in the odds of death were somewhat higher in surgical than medical patients or patients with lower severity of illness at admission. Although acute physiology scores had excellent discrimination in all age groups, discrimination decreased with age (e.g., c-statistics of 0.928 and 0.835 in patients younger than 45 and 85 and older, respectively). CONCLUSION: Our findings demonstrate incremental increases in the risk of hospital death associated with age that was independent of severity of illness and other prognostic factors. Although the current results may be less biased by differences in treatment goals than studies of general hospitalized patients, the lower discrimination of physiology scores in older patients suggests that unmeasured factors (e.g., functional status, patient preferences for care, differences in physician practices) may be of greater prognostic importance in older than in younger patients.  相似文献   
58.
PURPOSE: Surveys conducted by the American College of Physicians-American Society of Internal Medicine have shown that the public has varying opinions about the capabilities of internists. However, the perceptions of patients seeking care from internists remain uncertain. We wished to determine how patients visiting general internists perceived them and discover whether patients understood the differences between internists and other primary care physicians. SUBJECTS AND METHODS: We surveyed established adult patients visiting three general internal medicine clinics in Georgia, Iowa, and Vermont. Patients answered 11 questions about their perceptions of an internist's scope of care and selected which of 24 diseases, symptoms, or examination skills they thought an internist could manage. RESULTS: Patients completed 601 (66%) of the 911 surveys distributed. Nearly half of patients (45%) confused internists with family physicians and 39% thought internists could treat children. Patients with college education were more than twice as likely to know that internists were not interns (Odds ratio = 2.6, 95% confidence interval 1.8 to 3.8, P < 0.001) compared with patients having less education. Only 50% of patients thought an internist was trained in women's health. Significantly more (P < 0.001) patients demonstrated confidence in an internist's ability to treat symptoms (76%) than treat specific diseases (59%) or perform clinical examinations (54%). CONCLUSIONS: Established patients seeking care in internal medicine clinics lack consensus on the capabilities of internists, especially on how they differ from other specialties. Continued public education efforts should be considered to promote better understanding of the role of the internist as a specialist in adult medicine.  相似文献   
59.
Background The contribution of dysmotility to dysphagia in oesophageal cancer is unclear. Aim To examine oesophageal motility in patients with oesophageal carcinoma and to assess the effect of chemoradiotherapy on motility. Methods Stationary manometry and 24-hour pH-metry were performed in 12 patients with oesophageal carcinoma and one week following completion of chemoradiotherapy using 5-fluorouracil (5-FU), cisplatin and 40Gy radiotherapy. Results All patients had abnormal motility prior to treatment. Peristalsis was impaired in 11 patients with a mean (SD) of 25% (9) of waves normally propagated. Eight patients had 20% or more simultaneous waves. Following chemoradiotherapy, the percentage of waves normally propagated increased from 25% (9) to 52% (10) (p < 0.03) and normal peristalsis was restored in four patients. The percentage of simultaneous waves decreased from 38% (11) to 21.6% (10) (p=0.129) while the percentage of dropped or increased waves decreased from 20% (11) to 8.3% (4) (p=0.264). Conclusions Oesophageal motility is disturbed in oesophageal cancer. Dysphagia in oesophageal cancer may be partly explained by oesophageal dysmotility. This is improved by chemotherapy.  相似文献   
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