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51.

Prior research with male couples has focused on how sexual agreements can influence relationship dynamics, sexual risk taking, and health promoting behaviors. Little is known about the association between sexual agreements and the experience or perpetration of intimate partner violence (IPV) in this population. Our study sought to evaluate these associations using dyadic data from a sample of 386 male couples residing in the U.S. Both partners independently reported on their relationship characteristics, sexual agreements, and specific acts reflecting physical, emotional, controlling, and monitoring IPV in separate surveys. Participants were more likely to have experienced IPV in the past year if they were in a relationship for?≥?3 years versus?<?3 years (aOR?=?1.62, 95% CI?=?1.03–2.53). Among 278 couples who had formulated sexual agreements, men who concurred with their partners on being in an “open” relationship were less likely to have experienced IPV versus those in a “closed” relationship (aOR?=?0.47, 95% CI?=?0.25–0.89). However, participants were more likely to have experienced IPV if their partners believed they had previously broken their sexual agreement (aOR?=?2.79, 95% CI?=?1.03–7.52). The verbal explicitness and duration of sexual agreements were not associated with either experiencing or perpetrating IPV in the past year. However, increasing levels of depressive symptomatology were associated with a greater likelihood of both experiencing and perpetrating IPV. Our findings highlight the need to prioritize dyadic interventions for male couples that focus on skills building around enhancing mutual communication and negotiating sexual agreements to reduce IPV.

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53.
The loss of expression of the enzyme O6-methylguanine-DNA methyltransferase (the Mex- phenotype), which often results from cellular transformation, confers hypersensitivity to alkylating agents. We have observed two unrelated examples in which human cell lines have undergone a spontaneous alteration in their Mex phenotype during propagation in vitro. The change was reversible and was not the result of mutation. In both cases a loss of methyltransferase expression was accompanied by a simultaneous loss of expression of two metabolically unrelated enzymes: thymidine kinase and galactokinase. "Reversion" to methyltransferase expression was accompanied by simultaneous reexpression of both kinase activities. A third example of this coordinate gene regulation was seen with the Burkitt's lymphoma cell line Raji which expresses methyltransferase, thymidine kinase, and galactokinase at high levels. A thymidine kinase- Raji cell line derived by bromodeoxyuridine mutagenesis that is also Mex- was found to be galactokinase-. It appears that methyltransferase expression may in some instances be coordinately regulated with the tk and glk loci which are closely linked on human chromosome 17.  相似文献   
54.
Summary Long-(SL>6m) and short-sarcomere (SL<4m) fibres were isolated from the claw muscle of the yabby (Cherax destructor) during limb regeneration and at different stages of the moult cycle. Long-sarcomere fibres were more susceptible to the changes resulting from the moult-induced atrophy compared with the short-sarcomere fibres. Signs of atrophy included fibre erosion, loss of myosin filaments, a reduction in the diameter of myosin filaments and changes associated with the Z line. The intracellular structure of the fibres, however, remained intact in both fibre types. Fibres taken immediately prior to ecdysis could not be fully activated with Ca2+ or Sr2+ without breaking. In contrast fibres taken within 4 h after ecdysis could develop and maintain full force when activated by Ca2+ or Sr2+. The results suggest that loss of myofibrillar proteins via the moult-induced atrophy and/or events associated with fibre elongation may occur in the period just prior to ecdysis and that these changes may be responsible for the fibres inability to function during the premoult stage. Results from this study showed that short-sarcomere fibres add sarcomeres by at least two different mechanisms (1) transverse sarcomere splitting and (2) Z line splitting. Long-sarcomere fibres appear to be elongated by mechanism (s) other than those used by short-sarcomere fibres which possibly involve large electron dense structures which are positioned between the myofibrils and within the A and I bands. Results from the regenerating chelae limb bud showed that sarcomeres form from separate units comprising myosin filaments and actin filaments anchored into Z lines respectively. These sub-sarcomeric units then join together to form sarcomeres. Myofibril formation is aided by electron dense regions which are closely associated with the membrane system. These fibres although short in length and still within the non-functional limb bud could be activated by Ca2+ and Sr2+ suggesting that full fibre function exists before the chelae become functional. Regenerating muscle fibres consisted predominately of fibres with short-sarcomeres.  相似文献   
55.
Influenza is an important epidemic and pandemic illness associated with serious morbidity and mortality in unprotected communities. Patients at increased risk of infection are those with pre-existing cardiopulmonary disease including asthma. The influenza virus has the ability to produce antigenic changes posing problems for vaccine development. Influenza vaccines have been available for over 50 years. Despite the continuing global threat posed by infection and recommendations in many countries that immunisation should be widely given, uptake rates are variable and often poor. It has been demonstrated that infection with influenza and other respiratory viral pathogens can produce exacerbations of asthma throughout the age groups. Despite this, vaccine uptake rates in asthmatic populations are quite low. Poor uptake rates are attributed to a number of factors and we review the evidence for the widely held view that influenza vaccination produces exacerbations of chronic airflow obstruction including asthma. Observational studies have found conflicting results: some post immunisation changes in bronchial hyperreactivity and increased requirements of bronchodilator therapy have been in some, but not all, studies. Placebo-controlled trials have not demonstrated any clinical deterioration although one study showed a small reduction in peak expiratory flow rate. Intranasal administration of cold-adapted live vaccines and new nucleic acid vaccines are briefly considered. Live adapted vaccines have been shown to be effective in influenza immunoprophylaxis and limited data on their use in patients with asthma suggest that they can be administered safely. In conclusion, based up on current studies and evidence, it seems likely that influenza infection produces morbidity in patients with asthma but that any potential adverse effects of influenza immunisation are outweighed by the benefits in this population. However, placebo-controlled trials are few and only small numbers of asthmatic patients have been investigated.  相似文献   
56.
OBJECTIVES: Both benign prostatic hyperplasia and lower urinary tract symptoms (LUTS) have been shown to increase with age in men, but a causal relationship between prostate volume and symptoms has not been established. This study had two aims, to investigate the inter-relationships of age, symptoms, and various zonal measurements in the prostate and to assess the impact of heritable influences on symptom score. METHODS: Eighty-three monozygotic twin pairs and 83 dizygotic twin pairs were studied to determine age and LUTS as assessed by the American Urological Association symptom score. Their prostate volumes (total, transition zone, and peripheral zone) were measured by transrectal ultrasound. RESULTS: There was significant evidence of pairwise correlation between transition zone and symptom score (P = 0.04) and between age and symptom score (P = 0.03). Age also showed significant correlation with all volume measurements. Heritability appears to account for 82.6% of the variability in symptom score in men older than 50 years. CONCLUSIONS: This study provides evidence that age and transition zone volume play a role in LUTS, but also that their influence is not strong. Estimates of heritability suggest that hereditary factors contribute substantially to LUTS.  相似文献   
57.
OBJECTIVES: The new curriculum at King's College School of Medicine and Dentistry, which commenced in September 1996, requires all medical undergraduates to have a general practice placement throughout the 5 years of their medical education. DESIGN: This paper discusses recruitment, training and support of teaching practices for the new curriculum, reviews the distribution of single-handed general practices in the network and, via a selection of monitoring and evaluation procedures, discusses the implications of a policy which is inclusive of single-handed practices. The findings relate to the experience of the first semester of the first year of the new curriculum. It also examines the contributions that single-handed practices have made to the teaching network and the kind of support needed, if single-handed practices are to continue to contribute to the King's teaching network. SETTING: King's College School of Medicine and Dentistry. SUBJECTS: Medical undergraduates. RESULTS: The findings of this paper revealed that over a third of general practice provision is via single-handed practices in South-east London. Within the undergraduate teaching network, 10% of practices are single-handed. Students are welcomed and receive a learning experience comparable to those students in larger practices. Attendance at training events has proved difficult for some of these tutors, but the extra input from the department, in order to address this deficit, has not been onerous. Indeed, single-handed practices have not been unique with regard to difficulties in attendance at training events. CONCLUSIONS: The study concludes that single-handed practices can make satisfactory provision for undergraduates in the new curriculum and there is no evidence from this study to suggest otherwise.  相似文献   
58.
The present experiments examined the role of the two recently identified angiotensin II (Ang II) receptor subtypes, AT, and AT(2) , in the central nervous system regulation of luteinizing hormone (LH) and prolactin secretion in estrogen- and progesterone-treated ovariectomized rats. In this animal model, intracerebroventricular (icv) injection of Ang II stimulates LH and inhibits prolactin release. The specific Ang II receptor subtype antagonists losartan (AT(1) ) or PD123177 (AT(2) ) were administered (icv) in various doses (10 ng to 1,000 ng) 10 min prior to icv injection of Ang II (100 ng). Control animals were pretreated with artificial cerebrospinal fluid prior to Ang II administration. Blood samples for LH and prolactin determinations were taken from conscious, freely-moving rats prior to and following injection of the antagonists and Ang II. Water intake was measured. Ang ll-induced water intake was attenuated 62% by 1,000 ng losartan; water intake was not affected by lower doses of losartan or by any dose of PD123177. Ang ll-induced stimulation of LH release was abolished by the 1,000 ng doses of losartan and PD123177 and attenuated by the 500 ng doses of both drugs. Lower doses did not affect Ang ll-induced LH secretion. Ang ll-induced inhibition of prolactin release was significantly reduced by the 1,000 ng doses of both losartan and PD123177. Lower doses of either drug did not affect the Ang II inhibition of prolactin release. Previous studies had shown that Ang II administration into the anterior hypothalamus-medial preoptic (AHPO) area stimulated LH release. This brain area contains AT(1) receptors. To investigate the potential brain site where the AT(2) receptor may influence LH release, Ang II was injected into the locus ceruleus, a brain nucleus which contains predominately the AT(2) receptor subtype. Ang II administration into the locus ceruleus was paired with an injection of artificial cerebrospinal fluid or Ang II into the AHPO area. Injection of Ang II into the AHPO area stimulated LH release. Injection into the locus ceruleus did not affect LH secretion, nor did it modify the rise in LH elicited by administration of Ang II into the AHPO area. Plasma levels of prolactin were not altered by any of these injections. Taken together, these data demonstrate that, in estrogen- and progesterone-treated female rats, icv Ang ll-induced water intake is mediated by the AT, receptor subtype, while Ang ll-induced changes in LH and prolactin secretion appear to be mediated by both the AT(2) and AT(2) receptor subtypes. The latter observations are one of the first suggesting a potential function for the AT(2) subtype in vivo, although the physiological relevance of this observation, as well as the site of action for the effects on LH and prolactin, remain to be established.  相似文献   
59.
Long-term ambulatory urodynamic monitoring has been employed in 20 patients in an attempt to detect detrusor abnormality not appreciated by conventional cystometry. In 9 female patients with the "urge syndrome" it detected 2 previously unrecognised cases of detrusor instability; in 4 enuretic patients, only 1 of whom was known to be unstable previously, unstable contractions were confirmed, and 2 of 7 cystoplasty patients had high amplitude contractions detected only on ambulatory assessment. The technique provides a more sensitive index of lower urinary tract function than conventional cystometry in such patients.  相似文献   
60.
The last few years have witnessed considerable interest in the use of skeletal muscle to assist the heart. This review outlines developments of particular relevance and importance to this field during the past 12 months. The use of conditioned, fatigue resistant latissimus dorsi muscle has been proposed for cardiomyoplasty, for constructing separate pumping chambers, and for powering alternative assist systems. Although the cardiomyoplasty procedure has been applied clinically, the other techniques remain experimental, but promising, modes of support.  相似文献   
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