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91.
Causes of infant deaths were analyzed from the linked vital records of 1988 for the District of Columbia. According to a new cause-of-death classification, 57% of the deaths were attributed to "prematurity and related conditions," as compared with only 31% due to "disorders relating to short gestation and unspecified low birthweight" and respiratory distress syndrome (RDS) in the three-digit ICD-9 classification. Two thirds of infant deaths were "preventable." However, 92% of these occurred to infants weighing less than 1500 g. Not only was a greater proportion of black deaths (71%) preventable as compared to nonblacks (40%), but also 15% of the preventable deaths among blacks were due to causes unrelated to prematurity. The Infant Mortality Rate (IMR) in the District of Columbia would be reduced from 23.2 to 7.7 if all preventable deaths were prevented, to 20.9 if only the preventable deaths not related to prematurity were prevented, and to 15.2 if the percentage of "preventable" deaths among blacks was brought down to the level of nonblacks. Mortality from RDS was substantially higher in the District of Columbia compared with blacks nationally and appeared to offer the best opportunity for reduction. However, detailed examination of circumstances surrounding each infant death would be necessary to inform the strategies for the reduction in IMR. 相似文献
92.
Increased reactive oxygen species in familial amyotrophic lateral sclerosis with mutations in SOD1 总被引:1,自引:0,他引:1
Said Ahmed M Hung WY Zu JS Hockberger P Siddique T 《Journal of the neurological sciences》2000,176(2):88-94
Amyotrophic lateral sclerosis (ALS) is a paralytic disorder characterized by degeneration of large motor neurons of the brain and spinal cord. A subset of ALS is inherited (familial ALS, FALS) and is associated with more than 70 different mutations in the SOD1 gene. Here we report that lymphoblast cell lines derived from FALS patients with 16 different mutations in SOD1 gene exhibit significant increase of intracellular reactive oxygen species (ROS) compared with sporadic ALS (SALS) and normal controls (spouses of ALS patients). The ROS generation did not correlate with SOD1 activity. Further, cells incubated with vitamin C, catalase or the flavinoid quercetin significantly reduced ROS in all groups. The catalase inhibitor 3-amino-1,2,4-triazole resulted in a ten-fold increase of ROS in all groups. Neither L-nitroarginine, a nitric oxide synthase inhibitor or vitamin E altered the ROS levels. Thus, these studies suggest that hydrogen peroxide (H(2)O(2)) is a major ROS elevated in FALS lymphoblasts and it may contribute to the degeneration of susceptible cells. Further, we postulate a mechanism by which increased H(2)O(2) could be generated by mutant SOD1. 相似文献
93.
94.
PURPOSE: We report our 4-year experience with deep dorsal vein arterialization at 3 years' follow-up in young patients with pure cavernoocclusive dysfunction as an alternative to penile prosthesis implantation. MATERIALS AND METHODS: We performed a modified Furlow-Fisher operation (circumflex collaterals are preserved and the deep dorsal venous valves are not disrupted by a stipper) in 25 patients who did not have risk factors such as general arteriosclerosis, coronary heart disease, hypertension, hyperlipidemia and age (over 40 years). Patients with arterial disease diagnosed by Doppler examination were excluded from the study. Also, patients with abnormal penile biothesiometric and electromyographic findings were not included in the study. Beside the subjective and objective evaluation the efficacy of the operation was also assessed retrospectively in 18 patients by telephone according to items 3 (ability to achieve an erection) and 4 (ability to maintain an erection) of the 15-item International Index of Erectile Function (IIEF). RESULTS: With a mean follow-up of 28 months (range 4-42) subjective and objective success rates were 80 and 72% at 1 year's 75 and 62.5% at 2 years', and 70 and 60% at 3 years' follow-up. According to items 3 and 4 of the 15 item IIEF questionnaire the mean postoperative scores reached 1.55-3.44 and 1. 33-3.27 for items 3 and 4, respectively (p<0.01). Two patients (8%) showed signs of glans hypervascularization as a major complication and minor complications such as penile skin edema, subdermal hematoma, loss of penile skin sensation and early thrombosis of the anastomosis were found in a total of 8 patients (32%). CONCLUSIONS: Deep dorsal vein arterialization is a preferable choice in highly selected young patients as an alternative to penile prosthesis. 相似文献
95.
1 BACKGROUNDTheincidenceofCPis 0 .7per 1 0 0 0livebirths[1 ] .Becausecerebralpalsyinfluencesthewaychildrendevelop,itoftenresultsindevelop mentaldisability .Today ,more peoplehavecerebralpalsythananyotherdevelopmentaldis ability ,includingDownsyndrome,epilepsy ,andautism .Accordingtoasurveyconductedin1 986,2 .6%ofthepopulationofPakistaniaredisabled (includingbothphysicalandmentaldis abilities) .Childrenbetween 0~1 4 yearsinageconstitute 40 %ofthedisabled populationinPakistan .Routineme… 相似文献
96.
Sur RK Nayler S Ahmed SN Donde B Uijs RR Cooper K Giraud A 《South African journal of surgery. Suid-Afrikaanse tydskrif vir chirurgie》2000,38(1):13-16
Files of 8 patients with primary angiosarcomas treated in the Department of Radiation Oncology at the University of the Witwatersrand from 1982 to 1995 were identified. None of these patients had received prior radiotherapy or chemotherapy which would have predisposed them to the formation of an angiosarcoma. Slides of 6 patients were reviewed. Five of the 6 were confirmed as having angiosarcomas, while 1 patient was found to have a peripheral neuro-epithelial tumour. Four patients had angiosarcomas of the breast, while there was 1 patient each with angiosarcoma of the skin, intestine and brain. Complete excision was the primary modality of management whenever possible. Postoperative radiotherapy was given in cases of incomplete excision, patient refusal of radical surgery or gross tumour. Four patients died within 4 months of diagnosis. Three patients are alive (2 with no evidence of disease) 22-96 months after diagnosis. In 1 patient follow-up details were not available as he did not return for treatment. Angiosarcomas are aggressive malignant tumours arising from the endothelial cells. Complete surgical excision is the treatment of choice in the management of this aggressive disease, which has a poor prognosis. 相似文献
97.
GA Smith SD Strausbaugh C Harbeck-Weber DM Cohen BJ Shields JD Powers 《Pediatrics》1997,100(5):825-830
OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration = 5 cm in length that required suturing. Intervention. A total of 240 children were randomly assigned to one of four treatment groups. OUTCOME MEASURES: Pain felt during suturing was scored by suture technicians, research assistants, parents, and patients >/= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children. 相似文献
98.
Increased placental apoptosis in intrauterine growth restriction 总被引:2,自引:0,他引:2
Stephen C. Smith MB ChB Philip N. Baker DM E.Malcolm Symonds MD 《American journal of obstetrics and gynecology》1997,177(6):1395-1401
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401) 相似文献
99.