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101.
AIM: To provide a simple method for assessing centile change based on the British 1990 growth reference. STATISTICAL METHOD: The change in SD score over a period of time has SD square root of 2(1-r), where r is the correlation between the first and second SD score. This leads to an SD score for centile change. DATA: Annual height measurements from 2 to 9 years for 318 children from the French longitudinal growth study. RESULTS: The correlations between heights at different ages are higher for shorter measurement intervals and at older ages. The chance of a child's height centile falling one centile band width is correspondingly smaller for shorter measurement intervals and at older ages. An increase in height measurement error reduces the correlations and dramatically increases the chances of centile crossing. CONCLUSIONS: Quantitative height monitoring based on centile change is provided for whole year periods between 2 and 9 years of age. Effective monitoring requires the measurement error to be as small as possible.  相似文献   
102.
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible.  相似文献   
103.
Context  Ceftriaxone, an expanded-spectrum cephalosporin, is an antimicrobial agent commonly used to treat severe Salmonella infections, especially in children. Ceftriaxone-resistant Salmonella infections have recently been reported in the United States, but the extent of the problem is unknown. Objectives  To summarize national surveillance data for ceftriaxone-resistant Salmonella infections in the United States and to describe mechanisms of resistance. Design and Setting  Case series and laboratory evaluation of human isolates submitted to the Centers for Disease Control and Prevention from 17 state and community health departments participating in the National Antimicrobial Resistance Monitoring System (NARMS) for enteric bacteria between 1996 and 1998. Patients  Patients with ceftriaxone-resistant Salmonella infections between 1996 and 1998 were interviewed and isolates with decreased ceftriaxone susceptibility were further characterized. Main Outcome Measures  Exposures and illness outcomes, mechanisms of resistance. Results  The prevalence of ceftriaxone-resistant Salmonella was 0.1% (1 of 1326) in 1996, 0.4% (5 of 1301) in 1997, and 0.5% (7 of 1466) in 1998. Ten (77%) of the 13 patients with ceftriaxone-resistant infections were aged 18 years or younger. The patients lived in 8 states (California, Colorado, Kansas, Massachusetts, Maryland, Minnesota, New York, and Oregon). Nine (82%) of 11 patients interviewed did not take antimicrobial agents and 10 (91%) did not travel outside the United States before illness onset. Twelve of the 15 Salmonella isolates with ceftriaxone minimum inhibitory concentrations of 16 µg/mL or higher were serotype Typhimurium but these isolates had different pulsed-field gel electrophoresis patterns. Thirteen of these 15 isolates collected between 1996 and 1998 were positive for a 631–base pair polymerase chain reaction product obtained by using primers specific for the ampC gene of Citrobacter freundii. Conclusions  Domestically acquired ceftriaxone-resistant Salmonella has emerged in the United States. Most ceftriaxone-resistant Salmonella isolates had similar AmpC plasmid-mediated resistance.   相似文献   
104.
OBJECTIVES: To study the efficacy of otoacoustic emissions (OAEs) as a screening test for hearing impairment in children with acute bacterial meningitis. Hearing tests were performed before discharge from the hospital in an attempt to improve coverage and avoid delays in the diagnosis of postmeningitic hearing loss. METHODS: Children with bacterial meningitis were recruited from 21 centers. In the 48 hours before discharge from the hospital, all patients underwent a thorough audiologic assessment consisting of transient evoked OAEs, auditory brainstem responses (ABRs), otoscopy, and tympanometry. Hearing loss was defined as ABR threshold >/=30 dB. The results of OAE screening were compared with the gold standard of ABR threshold. RESULTS: Of 124 children recruited, we were able to perform both OAEs and ABRs on 110 children. Seven (6.3%) of the 110 children had ABR threshold >/=30 dB; 2 had sensorineural hearing loss and 5 had conductive hearing loss. At follow-up, hearing loss persisted in both cases of sensorineural hearing loss and no new cases were identified. All 7 children with hearing loss failed the OAE screening test. Ninety-four children with normal hearing thresholds passed the test, and 9 failed. Thus, the screening test had a sensitivity of 1.00 (95% confidence interval, 0.59 to 1.00), a specificity of 0.91 (0.85 to 0.97), a positive predictive value of 0. 44 (0.20 to 0.70), and a negative predictive value of 1.00 (0.96 to 1.00). CONCLUSIONS: OAE screening in children recovering from meningitis was found to be feasible and effective. The test was highly sensitive and reasonably specific. Inpatient OAE screening should allow early diagnosis of postmeningitic hearing loss and prompt auditory rehabilitation.  相似文献   
105.
Esophageal cancer has been associated with tobacco smoking, and nitrosamines are possible causative agents for this cancer. The present study investigated the metabolism of the tobacco carcinogens N'- nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1- butanone (NNK), and N-nitrosodimethylamine (NDMA), as well as the presence of xenobiotic-metabolizing enzymes in human esophageal tissues from individuals in the United States and Huixian, Henan Province, China (a high-risk area for esophageal cancer). All esophageal microsomal samples activated NNN and the metabolic rate was 2-fold higher in the esophageal samples from China than the USA. All microsomal samples activated NDMA. However, most of the microsomal samples did not activate NNK. Troleandomycin (an inhibitor of cytochrome P450 3A) decreased the formation of NNN-derived keto acid by 20-26% in the esophageal microsomes. The activities for NADPH: cytochrome c reductase, ethoxycoumarin O-deethylase, NAD(P)H: quinone oxidoreductase and glutathione S-transferase were present in the esophageal samples. Coumarin 7-hydroxylase (a representative activity for P450 2A6) activity was not detected in the esophageal microsomal samples. The activities for nitrosamine metabolism and xenobiotic- metabolizing enzymes were decreased (by 30-50%) in the squamous cell carcinomas compared with their corresponding non-cancerous mucosa. The presence of activation and detoxification enzymes in the esophagus may play an important role in determining the susceptibility of the esophagus to the carcinogenic effect of nitrosamines. Our results suggest that P450s 3A4 and 2E1 are involved in the activation of NNN and NDMA, respectively, in the human esophagus.   相似文献   
106.
A 54-year-old man was treated with weekly 24-h infusion of high-dose 5-fluorouracil (2600 mg/m2) and leucovorin (100 mg/m2) for metastatic colon cancer. At first, he tolerated the treatment well and no significant toxicity was identified. After a total of eight courses of treatment, a stable disease was observed, but mild shortness of breath was found on occasion. The patient had no previous history of cardiac disease and the heart performance assessed by left ventricular ejection fraction before treatment was normal. Unfortunately, acute pulmonary edema with lethal cardiogenic shock occurred during the ninth course of treatment, in spite of intensive medical treatment. The chest X-ray showed extreme cardiomegaly. Repeated assessment of his heart function by echocardiogram and ventricular ejection fraction revealed a very poor cardiac performance. Toxic cardiogenic shock during weekly 24-h infusion of high-dose 5-fluorouracil and leucovorin is extremely rare. To the best of our knowledge, no case has been reported in the English literature. We report a case and the relevant literature about the incidence, clinical picture and possible pathophysiology on 5-fluorouracil-related cardioxicity is reviewed.   相似文献   
107.
Disease management for chronic conditions is a call for collaboration among all parties of the health care system. The Caritas Christi Health Care System established a unified American Diabetes Association (ADA) recognized outpatient diabetes self-management education program (DSME) in each of its six hospital communities and has established an Internet data portal with managed care organizations to improve preventive care for thousands of patients with diabetes. This article describes the stepwise process of building the successful Caritas Diabetes Care Program and the central role of the Caritas Diabetes Registry over a 5-year period.  相似文献   
108.
Tolerance is defined as a decrease in responsiveness to a drug after repeated administration. Tolerance to the behavioral effects of hallucinogens occurs in humans and animals. In this study, we used drug discrimination to establish a behavioral model of lysergic acid diethylamide (LSD) tolerance and examined whether tolerance to the stimulus properties of LSD is related to altered serotonin receptor signaling. Rats were trained to discriminate 60 microg/kg LSD from saline in a two-lever drug discrimination paradigm. Two groups of animals were assigned to either chronic saline treatment or chronic LSD treatment. For chronic treatment, rats from each group were injected once per day with either 130 microg/kg LSD or saline for 5 days. Rats were tested for their ability to discriminate either saline or 60 microg/kg LSD, 24 h after the last chronic injection. Rats receiving chronic LSD showed a 44% reduction in LSD lever selection, while rats receiving chronic vehicle showed no change in percent choice on the LSD lever. In another group of rats receiving the identical chronic LSD treatment, LSD-stimulated [35S]GTPgammaS binding, an index of G-protein coupling, was measured in the rat brain by autoradiography. After chronic LSD, a significant reduction in LSD-stimulated [35S]GTPgammaS binding was observed in the medial prefrontal cortex and anterior cingulate cortex. Furthermore, chronic LSD produced a significant reduction in 2,5-dimethoxy-4-iodoamphetamine-stimulated [35S]GTPgammaS binding in medial prefrontal cortex and anterior cingulate cortex, which was blocked by MDL 100907, a selective 5-HT2A receptor antagonist, but not SB206553, a 5-HT2C receptor antagonist, indicating a reduction in 5-HT2A receptor signaling. 125I-LSD binding to 5-HT2A receptors was reduced in cortical regions, demonstrating a reduction in 5-HT2A receptor density. Taken together, these results indicate that adaptive changes in LSD-stimulated serotonin receptor signaling may mediate tolerance to the discriminative stimulus effects of LSD.  相似文献   
109.
110.
Success of de novo reimplantation of the artificial genitourinary sphincter   总被引:1,自引:0,他引:1  
PURPOSE: We evaluate our experience with de novo reimplantation of the artificial genitourinary sphincter with a particular emphasis on mechanical and nonmechanical failure rates. De novo reimplantation is defined as implantation of an artificial sphincter following removal of a previously placed sphincter for erosion and/or infection and a waiting period of several months. MATERIALS AND METHODS: A retrospective analysis of more than 400 patients with an artificial sphincter revealed 23 who underwent de novo reimplantation between January 1983 and October 1998. All patients were men with a mean age of 66.5 years (range 16 to 88) and all had a urethral cuff. Reasons for cuff removal were erosion in 12 cases (52.2%), infection in 10 (43.5%) and intraoperative urethral injury in 1 (4.3%). Mean waiting period was 6.8 months (range 1.5 to 32) between explantation and de novo reimplantation. Mean followup was 32.6 months (range 1 to 108). RESULTS: Of the 23 patients 20 (87%) had no mechanical or nonmechanical failures and 3 (13%) had nonmechanical failures, including 2 patients (8.7%) whose cuff eroded into the urethra and 1 (4.3%) who had recurrent urinary incontinence which was successfully treated with implantation of a tandem cuff. There were no mechanical failures or infections in this group of patients. CONCLUSIONS: Our study suggests that de novo artificial sphincter reimplantation is an excellent treatment option. It is safe and associated with complication rates that are comparable to those of primary implantation.  相似文献   
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