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31.
In this article we review some of the hormonal, sensory and experiential factors that regulate the onset and early maintenance of maternal responsiveness in rat and human mothers. We discuss data suggesting that, in humans, pregnancy is associated with changes in feelings and attitudes that may bear on adjustment to motherhood postpartum. Preliminary studies indicate that these changes are probably not hormonally mediated but are associated with a variety of psychosocial factors. Once women give birth, there is some suggestion that they undergo a period of elevated "responsiveness" which may be influenced by puerperal hormones and during which experiences with the newborn take on a special salience. Following the early postpartum period, a variety of factors influence maternal responsiveness, including the mother's affective state, her social relationships, and experiences caring for young. We discuss the relative contributions of psychological and physiological influences to maternal responsiveness at different stages of the maternity cycle.  相似文献   
32.
Maxillary resection defects have traditionally been technically difficult to treat with conventional radiation therapy. The irregular contours of the defect lead to an uneven distribution of the radiation doses. The potential to undertreat defects of microscopic involvement may leave residual disease. Tissue morbidity is high at isolated "hot spots" or at locations of excessive dose distribution. The use of a water-filled balloon bolus in conjunction with a balloon-retaining stent can significantly improve treatment efficacy and decrease tissue morbidity. This article describes a technique for the fabrication of a balloon-retaining stent for an orocutaneous defect.  相似文献   
33.
Gourlay T  Fleming J  Taylor KM 《Perfusion》1992,7(2):131-140
The Pall LG6 arterial line filter has been designed to remove free circulating leukocytes from the arterial line of the extracorporeal circuit employed in openheart surgery. The filter was evaluated and compared to a control filter (Pall Stat-Prime) in terms of its general blood handling characteristics, particularly with regard to the associated level of leukocyte removal. The gross air handling characteristics of the filters were also assessed together with pressure drop. It was found that the filters differed little in terms of all factors studied other than the level of leukocyte depletion. The LG6 filter was associated with substantial levels of leukocyte depletion, particularly the depletion of neutrophils. Over the 90 minute perfusion period the LG6 filter was found to be associated with a neutrophil depletion rate of around 70% while preferentially sparing lymphocytes. This compared to a 10-20% depletion rate in the control filter. This was achieved without apparently compromising the performance of the filter in terms of the other factors studied.  相似文献   
34.
This research was supported by a grant from The Foundation for Physical Therapy, Alexandria, VA. The purpose of this study was to determine the reliability of a quantitative measure of knee ligament laxity in vivo. The testing device simultaneously measures applied forces and resulting displacement at the knee through use of a multidimensional electrogoniometer, dynamometer, and a computer-assisted analysis system. Subjects were 30 females and 20 males, ranging in age from 18-32 years. Laxity tests were performed in the anterior/posterior (A/P) plane at 90 and 30 degrees of knee flexion, and the varus/valgus (V/V) plane at 20 and 0 degrees of knee flexion. Test-retest (N = 41) and intertester (N = 18) repeatability was assessed in all test positions by ANOVA and by coefficients of correlation and variability. No significant differences were found within testers for A/P or V/V tests 1 week apart at any angle tested. There were significant differences between testers for A/P and V/V tests. No significant differences were found between left and right sides, or between male/female values. Comparisons to other in vitro and in vivo studies are made. J Orthop Sports Phys Ther 1989;10(11):441-447.  相似文献   
35.
The quitting experience for smokers in sixth through twelfth grades   总被引:9,自引:0,他引:9  
The present study examined the withdrawal process for adolescents who had attempted to quit smoking. A sample of 622 6th through 12th graders were interviewed. Smoking status was reported prior to attempting to quit and its relationship with the withdrawal experience was evaluated. Although over half of those who smoked regularly reported trying to quit, 78% of the "quitters" were smoking six months after their quit attempt. Experiencing adverse withdrawal symptoms was related to smoking at daily levels before quitting; delaying trying to quit was associated with initiation of smoking at an early age; and quitting success was predicted by early quitting age, lower pre-quitting smoking levels, a lack of a prior quitting failure, and peer smoking. The results suggest that smoking intervention programs for adolescents should include components facilitating the quitting process that take into consideration youngsters' smoking and quitting histories.  相似文献   
36.
Mosaicism for an FMR1 gene deletion in a fragile X female   总被引:2,自引:0,他引:2  
Most cases of fragile X syndrome result from expansion of CGG repeats in the FMR1 gene; deletions and point mutations of FMR1 are much less common. Mosaicism for an FMR1 full mutation with a deletion or with a normal allele has been reported in fragile X males. Here we report on a fragile X female who is mosaic for an FMR1 full mutation and an intragenic deletion. The patient is a 4-year-old girl with developmental delay, autistic-like behaviors, and significant speech and language abnormalities. Southern blotting demonstrated the presence of a methylated full mutation, a normal allele in methylated and unmethylated forms, and an additional fragment smaller than the normal methylated allele. This result indicates that the patient is mosaic for a full mutation and a deletion, in the presence of a normal allele. By DNA sequence analysis, we mapped the 5' breakpoint 63/65 bp upstream from the CGG repeat region and the 3' breakpoint 86/88 bp downstream of the CGG repeats within the FMR1 gene. The deletion removed 210 bp, including the entire CGG repeat region. The full mutation was inherited from a premutation in the patient's mother. The deletion, which remained methylated at the Eag I and Nru I sites, was probably derived from the full mutation allele. Mosaicism of this type is rare in females with a fragile X mutation but should be kept in mind in the interpretation of Southern blots.  相似文献   
37.
The aim of this study was to assess the prevalence of hearing loss among people aged 65 years and over and to offer hearing aids where necessary. The study was carried out in a large health centre practice in Birmingham with a computerized record system. All patients aged 65 years, and a 20% random sample of patients aged 66 years and over were invited for interview. They were questioned about hearing loss and examined audiometrically. All patients with a hearing loss in the better ear of 35 decibels or more over the speech frequencies (0.5-4 kHz) were offered a hearing aid. A total of 322 patients attended (72% of those invited) and of these 34 patients already had a hearing aid. A further 142 patients were identified for whom an aid was recommended and 69 of these accepted. The acceptance rate was higher among men than women (57% compared with 43%). Sixty one patients (19% of those screened) had an asymmetrical hearing loss and of these 24 required consultant assessment; none had serious underlying pathology. There is a large unmet need for hearing aid provision. Simple audiometric assessment in health centres provides an opportunity to meet this need.  相似文献   
38.
39.
Utilizing real-time computer image analysis, individual spermatozoawere selected using microaspiration. Selection criteria werebased on potential hyperactivation motility characteristics;the amplitude of lateral head displacement >7.5 µm,curvilinear velocity >70 µm/s and linearity of <30%.For this pilot study, 16 patients (eight in each group) wererecruited. Using subzonal insemination (SUZI), up to five (mean= 4.4 ± 0.3) spermatozoa selected using computer-imagesperm selection (CISS) were microinjected, or up to 15 (mean= 12.8 ± 1.3 SD) unselected spermatozoa. In the groupwhich utilized CISS, 28 out of 49 (57%) oocytes were fertilizedcompared with 13 out of 52 (25%) utilizing conventional SUZI(P < 0.04); polyspermy was 20% (n = 10) and 2% (n = 1) respectively.CISS with SUZI showed increased efficiency in achieving fertilizationand is a novel approach to studying individual sperm functionin a sperm egg bioassay where gamete ratios are close to unity.  相似文献   
40.
Phosphoinositide kinases were characterized in membrane extracts of rat submandibular gland cells. Both phosphatidylinositol (PI) 4-kinase and phosphatidylinositol-4-phosphate (PI(4)P) 5-kinase phosphorylated endogenous substrates in reactions that were linear for up to 5 min, were activated by Mg2+ and showed maximal activity around neutral pH. PI 4-kinase was stimulated by Triton X-100 at an optimal concentration of 0.22%, but the detergent had an inhibitory effect on PI(4)P 5-kinase. Arachidonic acid (AA), at concentrations greater than 100 M, inhibited the activity of both enzymes in a dose-dependent manner. The inhibitory effect was replicated by other unsaturated fatty acids, but not by a saturated fatty acid of the sn-20 series. The nature of AA inhibition of the kinases was examined in enzyme kinetic studies with exogenous phosphoinositide and adenosine 5-triphosphate (ATP) substrates. Lineweaver-Burk plots of PI 4-kinase activity showed that AA had no effect on the apparent K m for either PI or ATP, but that the fatty acid significantly reduced V max (PI) from 331 to 177 pmol.mg–1.min–1 and V max (ATP) from 173 to 59 pmol.mg–1.min–1. This inhibitory action was consistent for PI(4)P 5-kinase kinetics, where again, AA did not alter apparent K m values, but lowered V max for both PI(4)P and ATP by around 50%. Since the combination of a reduced V max and an unchanged K m value indicates noncompetitive enzyme inhibition, it is proposed that AA regulates phosphoinositide cycle activity in submandibular gland cells by acting as a noncompetitive inhibitor of PI 4-kinase and PI(4)P 5-kinase.  相似文献   
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