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A review of cranial ultrasound examinations performed on 426 newborns over a 42-month period demonstrated a predominance of left-sided germinal matrix hemorrhage over both right-sided and bilateral germinal matrix hemorrhage. Distribution of intraventricular or intraparenchymal hemorrhage did not show this pattern. The reasons for left-sided predominance of germinal matrix hemorrhage remain speculative, and perhaps are related to cerebrovascular anatomic differences or to hemodynamic stresses related to patency of the ductus arteriosus.  相似文献   
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OBJECTIVES--To determine whether the TAP2 transporter gene, which lies between HLA-DP and HLA-DQ, is involved in determining susceptibility to systemic lupus erythematosus (SLE). METHODS--TAP2 types were determined by ARMS-PCR in 89 white patients with SLE and 156 control subjects. RESULTS--No particular TAP2 dimorphism or allele was associated with SLE or with any clinical/immunological subgroup of SLE. Furthermore, there was no evidence for significant linkage disequilibrium between TAP2 and HLA-DQ/DR in SLE. CONCLUSIONS--These data suggest that TAP2 is not a disease susceptibility gene for SLE and that the disease-predisposing haplotypes do not extend as far as TAP2. This indicates that any HLA-DP association with SLE must be independent of other class II (DQ/DR) associations.  相似文献   
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The hypothesis that sexual attitudes, as measured by the Sexual Opinion Survey, are related to the explicitness with which nude figures are drawn was examined. The presence or absence of various sexual and nonsexual anatomical features, as well as length and width measurements, were assessed in the drawing of nudes by 17 male and 23 female undergraduates. Individuals with relatively positive sexual attitudes (erotophiles), as compared with individuals with relatively negative attitudes (erotophobes), were more likely to include such details as a glans, a urinary meatus, and chest hair on male figures and pubic hair and nipples on female figures. Positive sexual attitudes were also associated with drawing figures with longer and wider penises, breasts, testicles, and mons. Relationships between sexual attitudes and the drawing of nonsexual body parts were generally not significant. The results are discussed in terms of the pervasive generality of sexual attitudes in influencing quite varied sex-related behaviors.  相似文献   
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This investigation was undertaken to compare maternal and neonatal cord serum levels of phenobarbital given orally to mothers anticipated to deliver very low birthweight infants at risk for neonatal intraventricular hemorrhage (IVH). Fifty women anticipated to deliver between 26 and 34 weeks' gestation agreed to receive a daily oral dose of 90 mg of phenobarbital. The umbilical cord to maternal phenobarbital concentration ratio at birth was 1.05 and remained constant after the first day of maternal therapy. Cord phenobarbital concentrations increased rapidly during the first 3 days until reaching a steady state by the end of the first week of therapy. In contrast to recent promising reports using large doses of phenobarbital given parenterally shortly before delivery, lower doses of oral phenobarbital did not reach cord levels reported to be protective against IVH or therapeutic as an anticonvulsant.  相似文献   
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The authors examined the development of diabetic retinopathy in a population-based cohort of persons with incident type 1 diabetes to investigate the possibility of lowered retinopathy prevalence and severity compared with previous US studies. A total of 474 diabetic persons from Wisconsin were followed from diagnosis through 4-14 years' duration during 1990-2002. Retinopathy was determined by fundus photography at 4, 7, 9, and 14 years' duration. Risk of developing retinopathy was modeled on demographic and diabetes-care characteristics by means of a generalized linear model using the complementary log-log link for interval-censored data. Prevalence of retinopathy increased with duration of diabetes, from 6% at 4 years to 73% at 14 years, and was highest among adults (> or =20 years of age). Risk of developing retinopathy increased with increasing duration, worse glycemic control, and age up to 20 years. Indicators of diabetes care were related to retinopathy through their effect on glycemic control. Improvements in diabetes care leading to better glycemic control may have contributed to the much lower prevalence and less severe retinopathy observed than expected on the basis of a previous report from the same region of Wisconsin. The observed decreased prevalence has important implications for persons with type 1 diabetes, since retinopathy is a serious microvascular complication.  相似文献   
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BACKGROUND: The lipophilicity of propofol has required dispersion in a soybean macroemulsion. The authors hypothesized that the anesthetic properties of propofol are preserved when reformulated as a transparent microemulsion rather than as a turbid macroemulsion and that the dose-response relation can be selectively modified by altering the microemulsion's surfactant type and concentration. METHODS: Microemulsions of propofol were formulated using purified poloxamer 188 (3%, 5%, 7%), and sodium salt of fatty acids (C(8), C(10), C(12)) in saline and characterized using ternary/binary diagrams, particle sizing, and stability upon dilution. Rats received propofol (10 mg . kg(-1) . min(-1)) as either a microemulsion or a conventional macroemulsion to determine these end points: induction (dose; stunned; loss of lash reflex, righting reflex, withdrawal to toe pinch) and recovery (recovery of lash, righting, withdrawal reflexes). After a 14-day recovery period, rats were crossed over into the opposite experimental limb. RESULTS: Forty-eight microemulsions (diameter, 11.9-47.7 nm) were formulated. Longer carbon chain length led to a marked increase in the volume of diluent necessary to break these microemulsions. All rats experienced anesthetic induction with successful recovery, although significantly greater doses of propofol were required to induce anesthesia with microemulsions irrespective of surfactant concentration or type than with macroemulsions. The sodium salt of C10 fatty acid microemulsion required the greatest dose and longest time for anesthetic induction. CONCLUSION: Propofol microemulsions cause induction in rats similar to that from macroemulsions. The surfactant concentration and type markedly affect the spontaneous destabilization and anesthetic properties of microemulsions, a phenomenon suggesting a mechanism whereby dose-response relation can be selectively modified.  相似文献   
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