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41.
Summary Quantitative bone histology was done in undecalcified sections of iliac crest bone specimens obtained from 84 normal American individuals. Samples were obtained within 12 h after death in a vertical and horizontal manner from both the right and left iliac crests. In addition to the determination of normal values of micromorphometric parameters of bone in these healthy American subjects, the following studies were carried out: (a) comparison of variance of micromorphometric parameters of bone obtained from the right versus left iliac bone (40 pairs), (b) comparison of micromorphometric parameters of bone obtained in a vertical versus horizontal manner (12 pairs), (c) evaluation of variance with increasing distance from the compact zone in bone samples obtained in a vertical manner (44 pairs), (d) analysis of variation between bone samples obtained more anteriorly versus posteriorly along the iliac crest (N=40), (e) comparison of differences in micromorphometric parameters obtained from age-matched men versus premenopausal women (N=12), and (f) plotting of histograms for assessment of distribution of micromorphometric parameters. The results show that histomorphometric data of bone cannot be easily compared when different techniques are employed for obtaining bone samples. Sampling variations are kept smaller when bone specimens are obtained in a vertical manner. Anterior/posterior variation does not cause major sampling error. If ranges of variation are taken into account, quantitative bone histology is a valuable tool for assessment of bone structure and bone cells.  相似文献   
42.
BACKGROUND: Intrauterine growth retardation (IUGR) is a major cause of short stature in childhood. Most but not all children experience catch-up growth by 2 years of age. METHODS: We investigated the endocrine profile (thyroid function, prolactin, cortisol, C-peptide and insulin-like growth factor-I [IGF-IJ levels) of 57 children with IUGR, aged 2-10 years, and compared it with 30 controls whose birth weight was appropriate-for-gestational-age. RESULTS: The hormonal profile for both groups was similar for thyroid hormones, prolactin, C-peptide and IGF-I. Cortisol levels were significantly lower in the IUGR group compared to controls (p <0,05). When the IUGR group was divided into 'catch-up' growth and 'non-catch-up' subgroups, the latter had significantly lower IGF-I levels (p <0.001). CONCLUSIONS: Lower cortisol levels in children born with IUGR may reflect impaired function of the hypothalamic-pituitary-adrenal axis associated with this condition. The significantly lower IGF-I levels of the 'non-catch-up' subgroup may be involved in their failure to grow.  相似文献   
43.
OBJECTIVE: To test the hypothesis that articles with negative results are more likely than articles with positive results to be published in journals with lower impact factor. DESIGN AND SETTING: We selected all of the randomized, placebo-controlled trials conducted during the neonatal period between October 1, 1998, and October 1, 2003. Trials were classified as having positive results or negative results (significant or no significant difference, respectively). Only studies dealing with primary outcomes (efficacy) were included. MAIN OUTCOME MEASURES: The impact factor of each journal was determined, and the sample size for each study was noted. RESULTS: There were 233 articles that fulfilled the inclusion criteria. There was a significant difference between the 2 groups in terms of impact factor (P = .03) but not sample size (P = .30). Impact factor correlated with both sample size and the type of study results (positive results vs negative results; P<.05). CONCLUSION: Articles with negative results are more likely than articles with positive results to be published in journals with lower impact factor.  相似文献   
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45.
Since 9/11, hospitals and health authorities have been preparing medical response in case of various mass terror attacks. The experience of Tel Aviv Sourasky Medical Center in treating suicide-bombing mass casualties served, in the time leading up to the war in Iraq, as a platform for launching a preparedness program for possible attacks with biological and chemical agents of mass destruction. Adapting Quarantelli's criteria on disaster mitigation to the "microinfrastructure" of the hospital, and including human behavior experts, we attempted to foster an interactive emergency management process that would deal with contingencies stemming from the potential hazards of chemical and biological (CB) weapons. The main objective of our work was to encourage an organization-wide communication network that could effectively address the contingent hazards unique to this unprecedented situation. A stratified assessment of needs, identification of unique dangers to first responders, and assignment of team-training sessions paved the way for program development. Empowerment through leadership and resilience training was introduced to emergency team leaders of all disciplines. Focal subject matters included proactive planning, problem-solving, informal horizontal and vertical communication, and coping through stress-management techniques. The outcome of this process was manifested in an "operation and people" orientation supporting a more effective and compatible emergency management. The aim of article is to describe this process and to point toward the need for a broad-spectrum view in such circumstances. Unlike military units, the civilian hospital staff at risk, expected to deal with CB casualties, requires adequate personal consideration to enable effective functioning. Issues remain to be addressed in the future. We believe that collaboration and sharing of knowledge, information, and expertise beyond the medical realm is imperative in assisting hospitals to expedite appropriate preparedness programs.  相似文献   
46.
A patient suffering from aggressive personality changes and cognitive impairment following head trauma, without neurological or anatomical imaging findings, underwent neuroSPECT scans with and without acetazolamide injection, both before treatment and during treatment with valproate. Acetazolamide injection induced increased prefrontal perfusion not evident at baseline. Valproate treatment was associated with increased prefrontal perfusion concomitant with clinical improvement and abolished response to acetazolamide challenge.  相似文献   
47.
OBJECTIVES: In a prospective study, we examined the effect of treatment with recombinant tissue plasminogen activator (r-TPA) on survival and morbidity in a series of high-risk children with infectious endocarditis (IE) after prolonged treatment with indwelling catheters. We hypothesized that r-TPA is an adjunctive therapy for dissolution of infected thrombi in drug-resistant IE. STUDY DESIGN: In the prospective 3-year study (1998-2001), we identified high-risk children with chronic illness and prolonged treatment with indwelling catheters who developed IE and overwhelming sepsis. Patients were allocated to receive r-TPA after persistent and enlarging intracardiac vegetations and failure to respond to conventional medical management. Complications associated with treatment, survival, and cardiac morbidity were observed. RESULTS: Seven infants were treated prospectively with r-TPA. All infants responded promptly to treatment, with resolution of the intracardiac vegetations within 3 to 4 days of commencement and without any adverse complications. All patients survived without long-term cardiac morbidity. CONCLUSION: Recombinant tissue plasminogen activator may offer a safe alternative to surgical intervention in the high-risk infant with IE.  相似文献   
48.
Bone ultrasound velocity curves of newly born term and preterm infants   总被引:6,自引:0,他引:6  
BACKGROUND: Ultrasound velocity (speed-of-sound [SOS]) has been proposed as a non-invasive method of evaluation of bone status in infants. We hypothesized that SOS correlates with both gestational age and birth weight. METHODS: We measured SOS within the first 96 hours of life at the right tibial midshaft location in 73 neonates ranging in gestational age from 25 to 41 weeks, and in birth weight from 825 to 3880 grams. We used the Sunlight Omnisense 7000p device (Tel Aviv, Israel). Results are expressed as meanS +/- 1 SD; statistical analyses included linear regression and computation of 95% CI regression lines; p<0.05 was considered significant. RESULTS: There was, as hypothesized, a significant correlation between gestational age (or birth weight) and SOS. There were no significant differences between males and females. Ninety-five percent confidence intervals were established. CONCLUSIONS: These data may be used as reference ranges for further studies.  相似文献   
49.
OBJECTIVE: This study was undertaken to evaluate whether the absolute nucleated red blood cell (RBC) count is elevated in term, appropriate-for-gestational-age (AGA) polycythemic infants. STUDY DESIGN: We compared absolute nucleated RBC counts taken during the first 12 hours of life in term, AGA infants with neonatal polycythemia (n = 29), and in control, nonpolycythemic infants (n = 37). We excluded infants of women with diabetes, hypertension, and alcohol, tobacco, or drug abuse, and those with fetal heart rate abnormalities or low Apgar scores, hemolysis, blood loss, or chromosomal anomalies. RESULTS: There were no differences between groups in birth weight, gestational age, or other demographic or perinatal factors. The hematocrit, RBC count, and absolute nucleated RBC counts were significantly higher and the platelet counts significantly lower in the polycythemic group. Regression analysis that included Apgar scores and gestational age showed a significant correlation of absolute nucleated RBC count with the polycythemia status only (P =.017). CONCLUSION: At birth, term AGA polycythemic infants have increased indices of active erythropoiesis. We speculate that this finding is suggestive of subtle fetal hypoxemia.  相似文献   
50.
BACKGROUND: The method of "massage therapy" has consistently shown increased weight gain in preterm infants. The weight gain was apparent during massages administered by professionals. AIMS: To replicate the results of increased weight gain in the course of "massage therapy" in preterm infants, and utilize a new, cost-effective application of this method by comparing maternal to nonmaternal administration of the therapy. STUDY DESIGN: Random cluster design. SUBJECTS: The study comprised 57 healthy, preterm infants assigned to three groups: two treatment groups--one in which the mothers performed the massage, and the other in which a professional female figure unrelated to the infant administered the treatment. Both these groups were compared to a control group. RESULTS: Over the 10-day study period, the two treatment groups gained significantly more weight compared to the control group (291.3 and 311.3 vs. 225.5 g, respectively). Calorie intake/kg did not differ between groups. CONCLUSIONS: Mothers are able to achieve the same effect size as that of trained professionals, allowing cost-effective application of the treatment within the neonatal intensive care unit.  相似文献   
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