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991.
Pregnancy and birth rates among sexually experienced US teenagers--1974, 1980, and 1983 总被引:1,自引:0,他引:1
We examined pregnancy rates and birth rates among United States teenagers aged 15 to 19 years in 1974, 1980, and 1983. Pregnancy rate refers to live births plus induced abortions per 1000 women; birth rate refers to live births per 1000 women. We present these rates for all teens aged 15 to 19 years and for teens aged 15 to 19 years who were sexually experienced. Data sources included National Center for Health Statistics birth records, Centers for Disease Control abortion surveillance reports, and Bureau of the Census population estimates. Sexual experience estimates came from national surveys of adolescent sexual behavior. Between 1974 and 1980, the pregnancy rate among all teens increased; the pregnancy rate among sexually experienced teens declined. From 1980 to 1983, the pregnancy rate declined among all teens and among sexually experienced teens. Birth rates among US teenagers (all teens and sexually experienced teens) declined between 1974 and 1983. Whereas the decline in the birth rate from 1974 to 1980 was primarily due to increased use of abortion, the decline from 1980 to 1983 related to the decrease in teenage pregnancies. 相似文献
992.
Background: Health care workers (HCWs) in Armed Forces are immunised against Hepatitis B virus (HBV), however they are not subjected to anti-HBs (antibody to Hepatitis B surface antigen) assessment after primary vaccination. The present study was undertaken to determine the protection offered by HBV vaccine in HCW. 相似文献
993.
BACKGROUND/PURPOSE: Conjoined twins often have different body composition and growth rate before separation. This may be because of differences in energy metabolism. The aim of this study was to investigate the energy expenditure, body composition, and calorie intake of thoracopagus conjoined twins with shared hepatic circulation but separate gastrointestinal tracts. METHODS: The twins were studied at two periods: (1) before separation (age, 73 days) and (2) after separation (age, 97 days). Calorie intake over the study periods was carefully documented. Respiratory gas exchange was measured by computerized indirect calorimetry. The postseparation weight ratio of twin A to twin B was used to approximate the preseparation weights. Body composition (total body fat) was calculated from skinfold thickness and anthropometric measurements. RESULTS: The body composition of the twins was different: body weight and total body fat were higher in twin B. Resting energy expenditure and calorie intake were markedly different between the conjoined twins before separation. In both twins, the energy expenditure increased after separation. After separation, the resting energy expenditure of the twins was similar. CONCLUSIONS: This study illustrates the difference in energy metabolism in a set of thoracopagus conjoined twins. The authors speculate that twin A was supplying nutrients to twin B resulting in increased energy expenditure before separation. This would explain the lower calorie intake and higher fat mass of twin B. 相似文献
994.
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996.
The poly(ADP-ribose)polymerase (PADPRP) gene has been implicated in
carcinogenesis through its role in DNA repair, replication and
recombination. A two-allele polymorphism in the chromosome 13 PADPRP
pseudogene has been studied in several racial groups. It has been suggested
that the B allele, which results from a 193-bp deletion in the gene,
predisposes to myeloma in Blacks. We assessed the association between
chromosome 13 PADPRP pseudogene genotype, mutagen sensitivity (a marker
reflecting host DNA repair capability), cigarette smoking, and lung cancer
risk in a minority lung cancer case-control study. The chromosome 13 PADPRP
pseudogene polymorphism was detected by polymerase chain reaction-based
analysis. Mutagen sensitivity was measured by an in vitro assay that
quantified bleomycin-induced chromatid breaks in peripheral blood
lymphocyte cultures. We examined 121 cases (80 African- Americans and 41
Mexican-Americans) with previously untreated lung cancer and 171 matched
controls. Our results suggested that the distribution of the PADPRP
pseudogene genotype frequencies was significantly different among
African-American and Mexican-American controls (P < 0.001). The
susceptibility genotype (i.e. at least one B allele) was found in 82.5% of
African-American cases, 79.4% of African- American controls, 53.7% of
Mexican-American cases, and 32.4% of Mexican-American controls. The odds
ratios (OR) and 95% confidence intervals for the PADPRP susceptibility
genotypes were 2.3 (95% CI = 0.7-8.0) and 3.2 (95% CI = 1.0-10.3) for
African-Americans and Mexican- Americans respectively, after adjustment by
age, sex, pack-years and mutagen sensitivity. Patients with the
susceptibility genotype appeared to have more mutagen-induced breaks than
did patients with the other genotype. Only adenocarcinoma was significantly
associated with the PADPRP susceptibility genotype (OR = 3.8). Mutagen
sensitivity (> or = 1 break/cell) was significantly associated with lung
cancer risk for both ethnic groups with increased ORs of above three-fold.
On stratified analysis, synergistic interactions were noted for the PADPRP
susceptibility genotype, mutagen sensitivity and smoking status. In
Mexican-Americans, the ORs for PADPRP susceptibility genotype, mutagen
sensitivity and both risk factors combined were 1.3, 2.7 and 17.1
respectively. The combined OR for the PADPRP susceptibility genotype and
smoking status was 15.6. Therefore, this polymorphism appears to be
associated with lung cancer risk. However, it is likely that no single
genotype is sufficiently predictive of risk and that a panel of
susceptibility markers is needed to define the high-risk subgroup.
相似文献
997.
S Hariharan VR Peddi VJ Savin CP Johnson MR First AM Roza MB Adams 《American journal of kidney diseases》1998,31(6):928-931
Recurrent or de novo glomerular disease is an important cause of graft dysfunction and eventual loss. Cyclosporine A (CyA) has improved short-term renal allograft outcome but has not altered long-term graft survival. The purpose of the current study is to determine the prevalence of such disease and its impact on graft function in the CyA era. From 1984 to 1994, 1,557 renal allografts were performed at the Medical College of Wisconsin and the University of Cincinnati. Patients were followed up for an average of 7.2 years (minimum, 1 year). Recurrent disease was diagnosed by renal biopsy in 98 (6.3%) patients after an average of 36 months. Demographic characteristics of patients with and without recurrent disease were similar. Glomerulonephritis was the most common finding, occurring in 73 patients, and included focal segmental glomerulosclerosis (FSGS), 25; IgA nephropathy (IgAN), 11; membranous (MN), 11; proliferative, 11; membranoproliferative glomerulonephritis (MPGN), 10; glomerular basement membrane (anti-GBM), 3; and systemic lupus erythematosus (SLE), two. Diabetic nephropathy was present in 22, hemolytic uremic syndrome (HUS) in two, and oxalosis in one. Graft loss occurred in 60 of 98 (61%) recipients. Half-life of the allograft was diminished in patients with recurrent disease, 2,038 +/- 225 versus 3,135 +/- 385 days, P = 0.002. The actuarial allograft survival at 1, 3, 5, and 8 years posttransplantation with recurrence was 88%, 74%, 57%, and 34%, respectively; and the corresponding graft survival for patients without recurrent disease was 80%, 70%, 64%, and 53%, respectively (P = 0.003). The risk of recurrent disease increased with length of graft survival from 2.8% at 2 years to 9.8% and 18.5% at 5 and 8 years, respectively. We conclude that recurrent disease is a significant problem after renal transplantation and is associated with decreased graft survival. 相似文献
998.
999.
MR Dr. sc. med. H. Becke 《Der Gyn?kologe》2004,37(12):1105-1109
Functional disorders of the urinary bladder of various types as an indication can be very receptive to reflex therapy and regulative treatment — especially without causing side effects — once pathological findings in organs have been excluded. This report focuses on acupuncture with moxibustion in reference to interference fields or blocking patterns of the spinal column. Stress incontinence has proven to be an ideal indication for acupuncture and neural therapy. Grade 1 stress incontinence still presents a clear indication for acupuncture. Grade 2 is treatable in parallel with physiotherapy, while grade 3 is a contraindication for acupuncture and requires surgical intervention. Treatment possibilities for nocturnal enuresis and irritable bladder syndrome caused by interference fields are illustrated by case reports. 相似文献
1000.