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81.
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   
82.
Measurement of patient satisfaction is an essential part of health outcome assessment. The purpose of this study is (a) to compare the stability of an aggregate summary measure and two separate summary measures of patient satisfaction; and, (b) to examine causal effects between two separate summary measures at two points in time. Data were collected from 1,451 Medicare HMO beneficiaries. In conclusion, (a) separate summary measures are recommended for constructing the measure of patient satisfaction and (b) moderate causal relationships and cross-lagged effects between the patient satisfaction measures of qualify of care and access to care were found.  相似文献   
83.
We examine the relationship between ethnicity and income as determinants of mammography use over a span of four years as a means of assessing community intervention impacts. The sample consisted of 1,447 women older than 34 years, living in Hawaii, who participated in the Behavioral Risk Factor Surveillance System (BRFSS). The percentage of women in the sample reporting a screening mammogram within the past two years was 31.4% in 1987, 54.1% in 1989, and 51.6% in 1990. Women of Hawaiian ancestry had the lowest percentage of mammogram use in the past two years (38.7%), while Japanese women had the highest percentage (49.8%). Results of logistic regression analysis indicate a significant increase in mammography use from 1987 to 1989 and no difference from 1989 to 1990. Findings also showed an association between age, income, and ethnicity with use in the past two years. Greater age, higher income, and Japanese origin, compared to Hawaiian, were all independently associated with increased odds of having had a mammogram in the past two years. We discuss results in terms of program evaluation and future research implications for community health surveys.  相似文献   
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The present study is a quantitative analysis of the unmyelinated fiber population in the fasciculus gracilis of the second cervical segment of cat and monkey. We find that unmyelinated fibers represent 13.7% of the total fiber population in this pathway in the cat and 18.9% in the monkey (Macaca fascicularis). The existence of such large numbers of these axons suggests that there may be a sizeable ascending fine primary afferent pathway in the fasciculus gracilis in cat and monkey whose destination is presumably the dorsal column nuclei. These findings are of interest in regard to classic ideas that the afferent fibers in the dorsal columns are large myelinated fibers that convey fine discriminative information to the dorsal column nuclei.  相似文献   
85.
The objective of this study was to compare the clinical and laboratory consequences of left and right displacement of the abomasum (LDA and RDA), short‐ and long‐term survival after surgery and the findings in cows, that could not be cured by omentopexy. Data from 564 cases of displaced abomasum (466 LDA, 98 RDA) were analysed retrospectively. Clinical and laboratory findings were compared between the two manifestations of DA. Survival was assessed after 10 days and after 15 months. Necropsy was carried out on cows that died or were killed. On arrival at the clinic, left displacement of the abomasum (LDA) cows had been recognized as diseased for longer. LDA occurred earlier in lactation, and more cows with right displacement of the abomasum (RDA) were pregnant. Overall clinical symptoms were more severe in RDA than in LDA cows. Heart rate was higher, body temperature was lower, inanition, abnormal faeces and ruminal stasis were more frequent in RDA cows. Leucocyte counts were higher, and potassium and chloride levels were lower in RDA cows. Acetonuria was more frequent in LDA cows. More LDA than RDA cows were released from the clinic as cured (82.0% versus 74.5%). However, survival after the early post‐surgical period was similar for RDA and LDA cows. At necropsy, diseases of the gastrointestinal system were the predominant finding in RDA cows, while in LDA cows, diseases of the liver and other concurrent diseases were more important.  相似文献   
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In this paper, we have derived some sufficient conditions for existence and uniqueness of equilibrium and global exponential stability in delayed Hopfield neural networks by using a different approach from the usually used one where the existence, uniqueness of equilibrium and stability are proved in two separate steps, rather we first prove global exponential convergence to 0 of the difference between any two solutions of the original neural networks, the existence and uniqueness of equilibrium is the direct results of this procedure. We obtain the conditions by suitable construction of Lyapunov functionals and estimation of derivates of the Lyapunov functionals by the well-known Young's inequality and Holder's inequality. The proposed conditions are related to p-norms of vector or matrix, p in [1, infinity] and thus unify and generalize some results in the literature.  相似文献   
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