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11.
The relationship of large and vascularized chorioangiomas to adverse pregnancy outcome is well recognized. We present a patient with a large placental tumor and signs of impending fetal cardiac failure. The angioarchitecture of the tumor depicted by three-dimensional (3D) power Doppler ultrasound enabled us to accurately diagnose a placental chorioangioma. During the follow-up period, quantitative flow data obtained using 3D power Doppler indicated altered hemodynamics in the tumor and concomitant improvement in the condition of the fetus, enabling us to manage the mother conservatively. Spontaneous delivery occurred at 38 weeks without any complications. This report demonstrates the potential value of 3D power Doppler in prenatal diagnosis and monitoring of pregnancies complicated by large, vascularized chorioangioma.  相似文献   
12.
A nonlinear forecast system for the sea surface temperature (SST) anomalies over the whole tropical Pacific has been developed using a multi-layer perceptron neural network approach, where sea level pressure and SST anomalies were used as predictors to predict the five leading SST principal components at lead times from 3 to 15 months. Relative to the linear regression (LR) models, the nonlinear (NL) models showed higher correlation skills and lower root mean square errors over most areas of the domain, especially over the far western Pacific (west of 155 degrees E) and the eastern equatorial Pacific off Peru at lead times longer than 3 months, with correlation skills enhanced by 0.10-0.14. Seasonal and decadal changes in the prediction skills in the NL and LR models were also studied.  相似文献   
13.
Clinical observations and laboratory experiments have suggested a role for testosterone in the development of prostatic cancer. Since physical training may act to lower testosterone levels, men who are very active may have a reduced risk of this cancer. To test this hypothesis, the authors prospectively followed 17,719 Harvard alumni (aged 30-79 years) from 1965 or 1969 to 1977, and 1980 to 1988 for the occurrence of prostatic cancer (n = 419). Physical activity was assessed in either 1962 or 1966, and again in 1977, based on self-reported stair climbing, walking, and sports played. Alumni who expended greater than 4,000 kcal/week at both assessments were at reduced risk of developing prostatic cancer (age-adjusted rate ratio, 0.12; 95% confidence interval 0.02-0.89) compared with their inactive counterparts who expended less than 1,000 kcal/week at both assessments. These results should be interpreted cautiously, since only one case of prostatic cancer was identified among alumni highly active at both assessments, who contributed 4% of total person-years to the analysis. Among alumni aged 70 years and older, those who extended greater than 4,000 kcal/week at either assessment had about half the risk of those who expended less than 1,000 kcal/week at either assessment (age-adjusted rate ratio, 0.53; 95% confidence interval 0.29-0.95). The authors attribute these findings to the increased precision with which physical activity could be measured when combining two activity assessments. Alternatively, long-term maintenance of a high level of physical activity may be necessary for further reduction of risk. There was no evidence of a dose-response relation.  相似文献   
14.
BACKGROUND: Food allergy is a common disease without effective treatment. Since strict elimination of food allergens may be difficult, strategies for effective intervention are urgently needed. OBJECTIVE: The aim was to investigate the prophylactic use of orally administrated FIP-fve, an immunomodulatory protein isolated from the edible mushroom Flammulina velutipes, in a murine model of food allergy. METHODS: BALB/c mice were immunized twice intraperitoneally with ovalbumin (OVA), at an interval of 2 weeks. Before and during each period of immunization, FIP-fve (200 microg per mouse) or phosphate-buffered saline was given orally every other day with a total of five doses. Then OVA-specific antibodies and cytokine profiles were determined. Subsequently, the mice were orally challenged with OVA. Symptoms of anaphylaxis, levels of plasma histamine, and histology of intestines were examined. RESULTS: Mice receiving oral FIP-fve treatment during sensitization to OVA had an impaired OVA-specific IgE response with a Th1-predominant cytokine profile. These mice were protected from systemic anaphylaxis-like symptoms induced by subsequent oral challenge with OVA. CONCLUSION: Oral administration of FIP-fve has a Th1-skewing effect on the development of the allergen-specific immune response, and may serve the purpose of immunoprophylaxis for food allergy and other allergic diseases.  相似文献   
15.
To determine the genetic origin of the complete hydatidiform mole, 20 abnormal pregnancies were studied with restriction fragment length polymorphism with five genomic probes: EJ 6.6, beta-globin gene, 3'alpha-hypervariable region, J-Bir, and St14. In the 12 cases of molar pregnancy, pure paternal origin was proved in 11 cases, but both maternal and paternal inheritance were shown in only one case. In the cases with pure paternal origin, all of the restriction fragment length polymorphisms were homozygous, although those of the fathers were heterozygous at 15 loci. In the four cases that mimicked hydatidiform mole but were diagnosed as hydropic change of villi, both paternal and maternal inheritance were noted. In the four pregnancies with blighted ovum, both paternal and maternal inheritance were shown in three cases; and in one case with a balanced translocation between chromosomes 13 and 14, only paternal inheritance was noted. This study showed that most of the complete hydatidiform moles were caused by fertilization of an empty egg by a duplicated haploid sperm, but rare exceptions may exist.  相似文献   
16.
From May 1, 1985 to December 31, 1991, a total of 4,962,707 serum samples from 8 population groups in Taiwan were tested for anti-human immunodeficiency virus type 1 (anti-HIV-1). In total, 256 samples were seropositive; of these individuals, 43 developed acquired immunodeficiency syndrome (AIDS): 29 were homosexuals; 5 were hemophiliacs; 8 were heterosexuals and 1 was of unknown risk. Although the prevalence of HIV-1 infection and AIDS remains low compared with other countries, since 1988 the increase has been rapid. Before 1977 the majority were homosexuals and hemophiliacs; thereafter the risk groups diversified, with a trend away from homosexuals and hemophiliacs towards heterosexuals and intravenous drug abusers (IVDAs). A few patients have caused serious social problems for the public, health care workers and families. Active community efforts are needed to achieve future success in the control of HIV-1 infection and AIDS in Taiwan.  相似文献   
17.
Stored sera from 181 Greek patients with hepatocellular carcinoma (HCC), 35 patients with metastatic liver cancer, and 416 hospital controls with diagnoses other than malignant neoplasm or liver disease were examined with first and second generation hepatitis C virus (HCV) enzyme immunoassays as well as with five HCV supplemental assays based on structural and nonstructural HCV peptides. Second generation HCV enzyme immunoassays were more sensitive than first generation assays. However, both assays had suboptimal specificity using the standard reactivity criterion (absorbance of sample to cutoff greater than or equal to 1.0). Specificity was improved by centrifugation and by using a sample's optical density to cutoff ratio greater than or equal to 3.0 or supplemental assays; in this instance the prevalence of antibodies to HCV was 13.3% (24 of 181), 0 (0 of 35), and 1.4% (6 of 416) in HCC, metastatic liver cancer, and hospital controls, respectively. A similar estimation of prevalence of antibody to HCV in HCC (12.5% or 4 of 32) was obtained when the recombinant immunoblot assay, second generation, was used to screen a random sample of HCC patients. The relative risk linking HCV to HCC was estimated as 10.4 (95% confidence interval, 4.2-26.0; P less than 0.0001). These data suggest that the prevalence of antibodies to HCV in HCC using stored sera has been previously overestimated even though the evidence of a causal association of HCV with HCC persists.  相似文献   
18.
The authors performed dexamethasone suppression tests (DST), TRH infusions, 72-hour urine collections, and lumbar punctures on a group of male depressed patients. Approximately 60% of the patients were DST positive and 33% had a blunted TSH response. Two biologic variables, the 8 a.m. postdexamethasone cortisol and the postprobenecid CSF 5-hydroxyindoleacetic acid (5-HIAA), accounted for over half of the variance in the behavioral measure, the Hamilton score. Plasma cortisol elevation was associated with high 3-methoxy-4-hydroxyphenyl glycol (MHPG) excretion; TSH blunting was associated with low urinary MHPG excretion. Comprehensive biologic measures showed certain significant interrelationships and correlations with the severity of depression.  相似文献   
19.
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs.  相似文献   
20.
Summary The disposition of the enantiomers of MK-571 (MK-0679 and L-668,018) following single i. v. doses of MK-571 (L-660,711) was studied in a three way cross-over study in 12 healthy male volunteers. Each volunteer received 75 mg, 300 mg and 600 mg i. v. doses of MK-571 at weekly intervals.The disposition of both enantiomers appeared dose-dependent, since the AUC increased disproportionately faster than the dose. The dose dependency was much more pronounced for L-668,018: its AUC increased 6-fold from the 75 to the 300 mg dose, 16-fold from 75 to 600 mg and 2.7 fold from 300 to 600 mg. For MK-0679, the corresponding increases in AUC were 4.8-, ll-, and 2.3 fold. Regardless of dose, the elimination of L-668,018 was more rapid than that of MK-0679.The disposition of MK-0679 needs to be investigated independently to detect any potential influence of L-668,018 on its disposition.  相似文献   
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