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191.
Despite advances in postnatal care, patients born with a congenital diaphragmatic hernia (CDH) suffer substantial morbidity and mortality. The present study was undertaken to determine the prognostic influence of prenatally-diagnosed liver herniation in the hemithorax in fetuses with CDH. The medical records of 48 patients evaluated for a prenatally-diagnosed left CDH were retrospectively reviewed. Patients were analysed according to the position of the liver by prenatal ultrasound; 32 fetuses had a major portion of the liver herniated into the left hemithorax ('liver up') and 16 had an intra-abdominal liver ('liver down'). Liver position was determined using colour-flow Doppler ultrasonography. There were two fetal deaths in the liver-up group and one in the liver-down group. The liver-up group more frequently required extracorporeal membrane oxygenation (ECMO) support (53 per cent) compared with the liver-down group (19 per cent). Postnatal survival was significantly less in the liver-up group (43 per cent) vs. the liver-down group (93 per cent). Fetuses with congenital diaphragmatic hernia and liver herniated into the hemithorax have a much worse prognosis than similarly afflicted fetuses without liver herniation. Prenatal ultrasonographic diagnosis of congenital diaphragmatic hernia allows for preparation for a critically ill newborn and aids in prenatal family counselling.  相似文献   
192.
CONDITION: Since 1990 (i.e., the year in which the number of abortions was highest), the annual number of abortions in the United States has decreased by 15%. REPORTING PERIOD COVERED: This report summarizes and reviews information reported to CDC regarding legal induced abortions obtained in the United States during 1995. DESCRIPTION OF SYSTEM: For each year since 1969, CDC has compiled abortion data received from 52 reporting areas: 50 states, the District of Columbia, and New York City. RESULTS: In 1995, a total of 1,210,883 legal abortions were reported to CDC, representing a 4.5% decrease from the number reported for 1994. The abortion ratio was 311 legal induced abortions per 1,000 live births, and the abortion rate was 20 per 1,000 women aged 15-44 years, the lowest ratio and rate recorded since 1975. Women who were undergoing an abortion were more likely to be young, white, and unmarried; most were obtaining an abortion for the first time. Approximately half of all abortions (54%) were performed at < or =8 weeks of gestation, and approximately 88% were performed before 13 weeks. Approximately 16% of abortions were performed at the earliest weeks of gestation (< or =6 weeks), approximately 17% at 7 weeks of gestation, and approximately 21% at 8 weeks of gestation. Few abortions were provided after 15 weeks of gestation -- approximately 4% of abortions were obtained at 16-20 weeks, and 1.4% were obtained at > or =21 weeks. Younger women (i.e., women aged < or =24 years) were more likely to obtain abortions later in pregnancy than were older women. INTERPRETATION: Since 1990, the number of abortions has declined each year. Since 1987, the abortion-to-live-birth ratio has declined; in 1995, it was the lowest recorded since 1975. This decrease in the abortion ratio reflects a trend that a lower proportion of pregnant women obtain induced abortion. ACTIONS TAKEN: The number and characteristics of women who obtain abortions in the United States should continue to be monitored so that trends in induced abortion can be assessed, efforts to prevent unintended pregnancy can be evaluated, and the preventable causes of morbidity and mortality associated with abortions can be identified and reduced.  相似文献   
193.
Life-threatening, recurrent ventricular tachycardia developed in a 54-year-old heart transplant candidate with ischemic cardiomyopathy. The episodes of ventricular tachycardia were refractory to aggressive medical management and implantable cardiac defibrillator placement. A Heartmate left ventricular assist device was implanted, in combination with isolated right coronary artery bypass grafting, which abolished any further episode of ventricular tachycardia. The patient successfully underwent cardiac transplantation 79 days later.  相似文献   
194.
PURPOSE: The aim of the study is to demonstrate the changes in visual evoked potentials (VEP) in treatment of amblyopia. MATERIAL AND METHODS: Pattern reversal VEP of 28 children treated because of amblyopia and 16 healthy persons were analysed. Before treatment and after treatment the results of the interocular amplitude difference ratio and interocular latency difference ratio were compared with standards. RESULTS: After treatment of amblyopia the percentage of normal interocular amplitude and latency difference ratios increased. CONCLUSION: Study of pattern VEP enables monitoring of amblyopia treatment.  相似文献   
195.
DNA topoisomerase VI from the hyperthermophilic archaeon Sulfolobus shibatae is the prototype of a novel family of type II DNA topoisomerases that share little sequence similarity with other type II enzymes, including bacterial and eukaryal type II DNA topoisomerases and archaeal DNA gyrases. DNA topoisomerase VI relaxes both negatively and positively supercoiled DNA in the presence of ATP and has no DNA supercoiling activity. The native enzyme is a heterotetramer composed of two subunits, A and B, with apparent molecular masses of 47 and 60 kDa, respectively. Here wereport the overexpression in Escherichia coli and the purification of each subunit. The A subunit exhibits clusters of arginines encoded by rare codons in E.coli . The expression of this protein thus requires the co-expression of the minor E.coli arginyl tRNA which reads AGG and AGA codons. The A subunit expressed in E.coli was obtained from inclusion bodies after denaturation and renaturation. The B subunit was overexpressed in E.coli and purified in soluble form. When purified B subunit was added to the renatured A subunit, ATP-dependent relaxation and decatenation activities of the hyperthermophilic DNA topoisomerase were reconstituted. The reconstituted recombinant enzyme exhibits a specific activity similar to the enzyme purified from S.shibatae . It catalyzes transient double-strand cleavage of DNA and becomes covalently attached to the ends of the cleaved DNA. This cleavage is detected only in the presence of both subunits and in the presence of ATP or its non-hydrolyzable analog AMPPNP.  相似文献   
196.
OBJECTIVES: Characterization and frequency of the rpoB gene mutations associated with rifampin resistance in Mycobacterium tuberculosis clinical isolates in Sevilla. METHODS: Characterization of rpoB mutations in 21 rifampicin-resistant strains of M. tuberculosis isolated during a three-year period (1994-1996) by three different molecular methods: a nonradioactive Single-strand conformation polymorphism (SSCP) analysis, DNA sequence analysis and a commercial method the line probe assay InnoLiPA. RESULTS: Five distinct rpoB mutations were identified. Ser531-->Leu mutation was detected in 14 strains (66.7%), H526-->Asp in 3 strains (14.3%), Ans512-->Ser in 1 strain (4.8%), Glu513-->Leu in 1 strain (4.8%). A nine nucleotide deletion (codon 510-513) was found in one strain (4.8%) while in the remaining resistant strain (4.8%) no mutation was detected. CONCLUSIONS: The frequency of the different mutations found in the rpoB gene, associated with rifampicin resistance in Mycobacterium tuberculosis clinical isolates in Seville, are similar to those previously reported. However, two new mutations has been detected: a nine nucleotide deletion (codon 510-513), and the Asn512-->Ser point mutation. The characterization of the mutations in the rpoB gene could serve as epidemiological marker for the rifampicin resistant clinical isolates of M. tuberculosis.  相似文献   
197.
RATIONALE AND OBJECTIVES: The authors evaluated the importance of positive sonographic findings in acute childhood pyelonephritis. MATERIALS AND METHODS: A total of 290 children (91 boys, 199 girls, aged 4 days to 15 years [median, 394 days]) with clinically suspected acute pyelonephritis underwent initial renal gray-scale ultrasound (US) and dimercaptosuccinate scintigraphic examination within 3 days of onset. A total of 173 patients underwent color or energy US examination. One hundred fifteen children with normal scintigraphic or pathologic findings (other than acute pyelonephritis) were excluded from further study; 170 patients with abnormal scintigraphic findings underwent follow-up scintigraphic scanning 60-90 days later. RESULTS: When pathologic structures other than acute pyelonephritis were not considered, the diagnostic value of gray-scale US was poor, with a sensitivity of 45.5%, a specificity of 86.6%, a positive predictive value of 88.8%, and a negative predictive value of only 40.6%. In regard to future renal scarring, gray-scale US had a positive predictive value of 67.7%, a negative predictive value of 40%, and a likelihood ratio of 1.16. Abnormal Doppler findings helped predict future scarring with a positive predictive value of 85.7%, a negative predictive value of 37.2%, a very low sensitivity of 26.9%, a high specificity of 90.6%, and a likelihood ratio of 2.87. CONCLUSION: Positive US Doppler findings in children with clinically suspected acute pyelonephritis indicate the need for immediate treatment. A positive initial gray-scale US examination does not predict future renal scarring, but a positive Doppler examination indicates a high probability of scarring. Negative gray-scale or Doppler US does not exclude a diagnosis of acute pyelonephritis and it cannot predict an absence of future scarring.  相似文献   
198.
Unilateral visuospatial neglect is now widely acknowledged to be a highly heterogeneous condition: The overt manifestations of visual neglect can vary as a function of task, spatial domain, and mode of response (at least). Double dissociations (sometimes of the strong form) have already been reported between most of the components of what was originally thought to be a relatively stable construct within the visual modality. Nonetheless, throughout successive fractionations of neglect, reported cases of bidirectional task-specific neglect after unilateral brain damage are rare. We now report two such cases. After right hemisphere stroke, the first patient reliably showed severe left neglect on cancellation but right neglect on line bisection. After left hemisphere stroke, the second case showed right neglect on cancellation but left neglect on line bisection. Extensive investigation of case 1 confirmed our previous conjecture that the crucial distinction between these tasks lies in the presence or the absence of an overt target. In contrast to cancellation, line bisection demands the internal computation of the location of the "target" (the midpoint), followed by executing a motor response toward the precise location of that "imaginary" midpoint. The relative attentional and premotor contributions of the intact and damaged hemispheres to these forms of bidirectional neglect are also assessed.  相似文献   
199.
The aim of this work was to specify the time course of response to interferon (IFN) of hepatitis G virus (HGV) and hepatitis C virus (HCV) in coinfected individuals. A group of 33 patients, undergoing 12 months of IFN therapy for chronic hepatitis C, was screened for the presence of both HGV and HCV RNAs to select seven coinfected patients. Spontaneous recovery from HGV infection was excluded through the detection of antibodies to the envelope-2 protein of HGV and HCV isolates were genotyped. Within three months of treatment, we found that HGV RNA was transiently cleared in 6/7 patients, but the rate of long-term favorable response was very low (1/7). In addition, considering the same individuals separately, it was shown that HGV and HCV responded to IFN with different kinetics in 5/7 patients. Taken together, these results underscore the importance of the virological basis of the resistance to IFN treatment.  相似文献   
200.
The definition of envy is commonly based on psychoanalytical views of organizational culture. The purpose of this paper is to describe envy in a nursing community. The population study consisted of random sample of 120 subjects drawn from among the employees of one central hospital in Finland. The study material consisted of data collected by questionnaires (response rate 65%). The data were processed by various statistical methods. Open-ended questions were analysed by inductive content analysis. The results of this study indicated that the employee's view of his/her official position in the nursing community, his/her relationships with his/her fellow workers and the management as well as relationships with other nursing communities are all related to envy. The employee's view of his/her official position intensified his/her feelings of envy, if he/she had other negative feelings, anxiety, dissatisfaction with him/herself, and negative feelings towards fellow workers. The major object of envy was fellow workers' salaries. Envy towards other nursing communities was generated by alleged differences in the amount of labour, or by the charge nurse's greater interest in other sections. Employees coped with envy by hiding these feelings and being modest. Women coped with envy by being silent, while men denied the value of the object of envy.  相似文献   
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