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101.
The complete sequence (22 kilobases) of murine coronavirus gene 1 encoding the putative proteases and RNA polymerase 总被引:52,自引:0,他引:52
102.
Normative values of bone parameters of children and adolescents using digital computer-assisted radiogrammetry (DXR). 总被引:2,自引:0,他引:2
Ansgar Malich Martin G Freesmeyer Hans-Joachim Mentzel Dieter Sauner Joachim Boettcher Alexander Petrovitch Werner Behrendt Werner A Kaiser 《Journal of clinical densitometry》2003,6(2):103-111
PURPOSE: To verify whether estimation of bone mineral density (BMD) using digital X-ray radiogrammetry (DXR) is possible on children and to determine normative values of both such a DXR-BMD estimate and a corresponding metacarpal index (DXR-MCI) on. PATIENTS AND METHODS: In retrospect, X-rays were selected of the hands of 200 healthy Caucasian children (120 boys and 80 girls, aged 4-18 yr). The involved children were selected among a larger group of children submitted to the surgical department of our institute for evaluation of a suspected fracture after an occurred trauma. All children with a verified fracture or a chronic bone-related disease, including bone age retardation or acceleration, were excluded from the study. Furthermore, only conventional X-rays with the same film and capture parameters were included. The images were scanned and analyzed using the Pronosco X-posure system V.2 (Sectra Pronosco, Denmark). DXR-BMD, DXR-MCI, and a porosity index (DXR-PI) were automatically calculated using the midshafts of the metacarpals II-IV. Mean values of DXR-BMD and DXR-MCI were calculated separately for girls and boys in 2-yr intervals. RESULTS: In the present study the system has been demonstrated to be capable of calculating DXR-BMD from conventional X-rays of the hand from children down to approx 6 yr of age. This ability depended somewhat on the diameter and the length of the involved metacarpals. The success rate was higher for large bones than for small bones. The system succeeded in analyzing the images of 110 boys and 68 girls. Values of DXR-BMD were observed to increase with age from 0.40 g/cm2 to 0.62 g/cm2 in the male group and from 0.39 g/cm2 to 0.54 g/cm2 in the female group. Girls aged 11-12 yr had a higher DXR-BMD than did boys, corresponding to the earlier entry to puberty of girls. Standard deviations (SDs) reached values of up to 0.05 g/cm2. DXR-MCI increased with age from 0.36 to 0.47 for boys and from 0.34 to 0.49 for girls with a maximum SD of 0.06. The correlation between DXR-BMD and age was r=0.83 and r=0.84 for boys and girls, respectively. The corresponding correlations for DXR-MCI was lower, with observed correlations of r=0.63 (boys) and r=0.68 (girls), respectively, with p<0.01 in all cases. The DXR-PI did not reveal a significant correlation to age (r=-0.31 and r=0.04. respectively) and showed SDs marginally higher than the calculated mean values. CONCLUSION: The newly available DXR-methodology seems to offer the ability to determine DXR-BMD and DXR-MCI in children starting with a bone age of 6. This possibility may be of special relevance for children suffering from chronic bone diseases that require repeated X-rays of the hand (e.g. to determine bone age). The acquired normative data suggest that the measurements are of clinical value owing to low age-dependent variability (SDs) relative to an observed high increase with age. The clinical value of the porosity index (DXR-PI) remains uncertain and is limited owing to a high inter-individual variability. 相似文献
103.
Serum interleukin 5 concentrations in atopic and non-atopic patients with glucocorticoid-dependent chronic severe asthma. 总被引:7,自引:1,他引:6
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BACKGROUND--Interleukin (IL)-5 is thought to play a part in asthmatic bronchial mucosal inflammation and is a potential therapeutic target. Detectable serum IL-5 concentrations have been found previously in a proportion of patients with acute severe asthma, but not in the same patients following oral glucocorticoid therapy or in normal controls. A study was undertaken to investigate whether or not IL-5 is detectable in the serum of patients with glucocorticoid-dependent chronic severe asthma. METHODS--Serum concentrations of IL-5 were measured in 29 patients with stable oral glucocorticoid-dependent chronic severe asthma (mean PEFR 59.7% predicted) and seven normal controls using a specific enzyme-linked immunoassay calibrated with recombinant human IL-5 standards (lower limit of sensitivity 40 pg/ml). RESULTS--Interleukin 5 was detectable in the serum of 15 of the 29 patients at a median concentration of 150 pg/ml (range 40-690), but was undetectable in the serum of all the control subjects. The patients with detectable serum IL-5 concentrations did not differ from those with undetectable concentrations in terms of atopic status, disease severity (percentage predicted PEFR or FEV1), prednisolone dosage, serum IgE concentrations, or peripheral eosinophil count. CONCLUSIONS--Interleukin 5 is detectable in the serum of a proportion of both atopic and non-atopic patients with chronic severe asthma, and concentrations in these patients were higher than in normal controls. These observations are compatible with the hypothesis that IL-5 release occurs in these patients during a period of stable asthma despite systemic glucocorticoid therapy. 相似文献
104.
Laparoscopic feeding jejunostomy: also a simple technique 总被引:2,自引:1,他引:1
Michael H. Albrink James Foster Alexander S. Rosemurgy Larry C. Carey 《Surgical endoscopy》1992,6(5):259-260
Summary Placement of feeding tubes is a common procedure for general surgeons. While the advent of percutaneous endoscopic gastrostomy
has changed and improved surgical practice, this technique is contraindicated in many circumstances. In some patients placement
of feeding tubes in the stomach may be contraindicated due to the risks of aspiration, gastric paresis, or gastric dysmotility.
We describe a technique of laparoscopic jejunostomy tube placement which is easy and effective. It is noteworthy that this
method may be used in patients who have had previous abdominal operations, and it has the added advantage of a direct peritoneal
view of the viscera. We suggest that qualified laparoscopic surgeons learn the technique of laparoscopic jejunostomy. 相似文献
105.
106.
Recent experience with flexion-distraction injuries of the lumbar spine associated with blunt abdominal trauma and the use of a lap belt alone has caused us to review our experience over the last 7 years. Eighteen patients were identified, with an average age of 22 years, and an average followup of 34 months. Fifteen were involved in motor vehicle accidents, with 11 being single-vehicle accidents. Of note, 12 of the 15 were rear seat passengers with lap belts only. Twelve patients suffered abdominal injury, seven requiring operative intervention, mainly for hollow viscus injury. In three patients, a delay of 24 hours or more occurred before recognition of intra-abdominal pathology requiring surgical therapy. One patient had an unrecognized spinal fracture for 2 weeks after abdominal surgery for a perforated viscus. The spinal injury was carefully assessed and analyzed for prognostic factors. Six were graded excellent, five good, four fair, and one poor. One case of paraplegia associated with avulsion of the spinal cord from distraction is reported. Prognostic factors included the amount of facet joint involvement and the degree of initial kyphosis. Those having greater than 17 degrees of kyphosis had a poor prognosis. Early recognition of the constellation of injuries involving the spine and abdomen associated with the use of the lap belt is recommended with surgery to the spinal fracture as outlined. 相似文献
107.
108.
Martin Haupt Alexander Kurz Stefan Pollmann Barbara Romero 《Journal of neurology》1992,239(5):248-250
Summary Ninety outpatients with Alzheimer's disease according to ICD-10 diagnostic draft criteria were studied to test the hypothesis that cases with a familial aggregation are different from cases without such an aggregation with respect to cognitive impairment. In all cases the diagnosis of Alzheimer's disease was confirmed by prospective observation within 12 months of initial evaluation. Patients were divided into two groups: one consisting of 23 patients with a familial aggregation, the other consisting of 67 patients without secondary cases among first-degree relatives. By means oft-tests differences in impairment of cognitive functions between the groups were calculated. The results did not yield statistically significant differences between the groups for any of the neuropsychologically investigated cognitive deficits. Thus the hypothesis that the presence of a familial aggregation may lead to a distinct phenotype in Alzheimer's disease was not confirmed. 相似文献
109.
N L Leland D J Petersen M Braddock G R Alexander 《Public health reports (Washington, D.C. : 1974)》1995,110(1):53-58
This study used the 1983-86 U.S. Linked Live Birth-Infant Death Files to examine variations in pregnancy outcomes among 38,551 U.S. resident black and white adolescents ages 10 through 14. The birth rate was 4.29 per 1,000 for blacks, more than 7 times the rate for whites (.59 per 1,000). Black mothers had higher proportions of very low and low birth weight infants than did whites (very low birth weight: 3.7 versus 2.6; low birth weight: 15.0 versus 10.5). Neonatal and infant mortality rates were higher among very low birth weight and low birth weight white infants. Neonatal and infant mortality rates were similar for normal birth weight infants of both races, but were 3.7 to 7.4 times higher among black infants with birth weights more than 4,250 grams. Logistic regression indicated that black mothers were at higher risk for having infants who were low birth weight, very low birth weight, small for gestational age, preterm, and very preterm. There were no differences by race for neonatal, postneonatal, and infant mortality. While the risk for poor pregnancy outcomes is great among young adolescents, young black adolescents appear to be particularly vulnerable. Attempts to reduce unintended pregnancies in this group should receive highest priority. 相似文献
110.
Active and passive surveillance for communicable diseases in child care facilities, Seattle-King County, Washington.
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J K MacDonald J Boase L K Stewart E R Alexander S L Solomon R L Cordell 《American journal of public health》1997,87(12):1951-1955
OBJECTIVES: The purpose of this study was to develop and evaluate models for public health surveillance of illnesses among children in out-of-home child care facilities. METHODS: Between July 1992 and March 1994, 200 Seattle-King County child care facilities participated in active or enhanced passive surveillance, or both. Reporting was based on easily recognized signs, symptoms, and sentinel events. Published criteria were used in evaluating surveillance effectiveness, and notifiable disease reporting of participating and nonparticipating facilities was compared. RESULTS: Neither surveillance model was well accepted by child care providers. Enhanced passive and active surveillance had comparable sensitivity. Reporting delays and the large amount of time needed for data entry led to problems with timeliness, especially in terms of written reporting during active surveillance. CONCLUSIONS: Widespread active public health surveillance in child care facilities is not feasible for most local health departments. Improvements in public health surveillance in child care settings will depend on acceptability to providers. 相似文献