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11.
The effects of treating ovariectomised nulliparous and multiparous ewes with progesterone and estrogen on maternal behavior with or without vagino-cervical stimulation were investigated. Following 48 h of estrogen treatment there was neither evidence for stimulation of maternal behavior, nor a reduction in aggressive behavior, towards lambs by either multiparous or nulliparous ewes compared with control treatment (injections of the oil vehicle). Following 5 min of mechanical vaginocervical stimulation, the multiparous estrogen-treated ewes showed both positive maternal responses (low pitch bleats, licking, sniffing and approaching the lamb) and a reduction in aggression (butts) and negative behavior (withdrawal from the lamb) towards the lambs, whereas the nulliparous ewes showed only a reduction in aggression and negative behavior. Neither group showed positive maternal responses following vaginocervical stimulation without steroid priming. When the ewes received two weeks of progesterone priming prior to estrogen treatment, both multiparous and nulliparous ewes showed reduced aggression towards, and withdrawal from, the lambs compared to the control condition, but no positive maternal responses apart from an increased sniffing of the lamb. After vaginocervical stimulation positive maternal responses showed by multiparous ewes were significantly potentiated compared to those shown following estrogen treatment alone. Nulliparous ewes remained unresponsive on positive maternal behaviors. These studies show that hormonal priming has little effect in inducing the onset of maternal behavior in multiparous or nulliparous sheep but is an essential prerequisite for vaginocervical stimulation to do so in multiparous animals.  相似文献   
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Estimations of the average discharge rates in vasoconstrictor fibres to skeletal muscle, kidney, intestine and skin at varying levels of arterial baroreceptor activity were made by comparing quantitatively the reflexly induced vascular responses with those obtained with stimulations of the regional vasoconstrictor fibres at known frequencies. The results indicate that withdrawal of baroreceptor restraint was normally followed by a considerably lower firing rate in renal vasoconstrictor fibres than in e.g. skeletal muscle vasoconstrictor fibres. A complete elimination of the inhibitory influence induced vasoconstrictor fibre discharge rates up to 8 imp/s in skeletal muscle but only at most 4 imp/s in the kidney. Intestinal vasomotor fibres were found to be activated to approximately the same extent as those to skeletal muscle. The vasomotor fibres to the cutaneous arterio-venous anastomoses were evidently not activated when the baroreceptors were unloaded. The reason for this non-uniform activation of the different sets of vasoconstrictor fibres seems to be different levels of spontaneous activity in the respective “neuron pools” in the bulbar vasomotor centre. The renal vascular responses to baroreceptor unloading became augmented when the excitatory level in the vasomotor centre was enhanced, as e.g. when the animal became acidotic.  相似文献   
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BACKGROUND: Studies have shown that bereaved individuals suffer increased rates of physical and mental ill health. Bereavement support has recently been advocated as an area of prevention in primary care, with suggestions that general practitioners (GPs) should adopt protocols for the active follow-up of their bereaved patients, which relies on the early notification of deaths by hospitals and hospices. Little is known about the routine care currently provided by GPs and primary health care teams (PHCTs) to support their bereaved patients. AIMS: To explore GPs' perceptions of patient death notifications by hospitals and hospices. To describe practice policies relating to patient deaths and the provision of bereavement support. METHOD: Postal questionnaires were sent to senior partners of a random sample of 500 general practices in South Thames Health Region. RESULTS: Three hundred and fifty-three practitioners responded (71%). Hospitals were perceived to be significantly slower than hospices in notifying deaths (P < 0.0001). One hundred and ninety-six practices (56%) kept death registers, 230 (65%) discussed deaths together, and 142 (40%) identified bereaved relatives. One hundred and thirty-seven practices (39%) routinely offered bereaved relatives contact with a PHCT member; while 133 (38%) supported only those who asked for help. Routine support was significantly more likely to be provided by practices that kept a death register, discussed deaths together, identified bereaved relatives, and had a special interest in palliative care. CONCLUSIONS: GPs perceive hospitals to be slower than hospices at notifying deaths, particularly in the first 24 hours. They are divided over whether bereavement support should be proactive or reactive. Keeping a practice death register, discussing deaths together, and identifying newly bereaved relatives are activities related to providing routine bereavement care.  相似文献   
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Older gay men experience an elevated prevalence of adverse health conditions that may be compounded by age-related deterioration. Some of these conditions may be ameliorated by regular adherence to physical activity (PA). However, many gay men participate in less PA than their age-matched heterosexual counterparts. With a focus on gay men aged 60 and over, the aims of this review were to examine the evidence for older gay men's engagement with PA and the research approaches used to describe this group. A systematic search of six academic databases (Academic Search Premier, Cinahl, PubMed, Sport Discus, APA PsychInfo and APA PsychArticles) generated 23 papers from 1970 to 2020 that focused on older gay men's engagement with PA. Although surveys were well represented in the literature, further studies utilising qualitative methodological frameworks have the potential to inform targeted interventional programs aimed at reducing less health disparities. The value of PA in older adults lies principally in improved performance of activities of daily living, independent living, increased longevity, decreased cognitive decline and improved mental well-being.  相似文献   
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The sexual behaviour of 7 pairs of marmosets was observed during 30 minute tests for 44-68 days and blood samples were collected from females for measurement of plasma progesterone, testosterone and oestrone. Copulations occurred throughout the ovarian cycle of 24-30 days. Females used a "tongue-flicking" display both as an invitational behaviour (proceptive tongue-flicks) and during copulation (receptive tongue-flicks) most frequently during the peri-ovulatory period. Frequencies of proceptivity were correlated positively with high mean levels of testosterone and oestrone during the cycle and with a short follicular phase. Males showed significant increases in tongue-flicks, mounts and ejaculations during the peri-ovulatory phase, together with a shortened post-ejaculatory interval and increased duration of penile erection after ejaculation. A retrospective analysis showed that these changes in the males' behaviour occurred only during tests where females were proceptive and not during other tests in the peri-ovulatory period. Females refused significantly more of the males' mounting attempts during the luteal phase and a corresponding reduction in mount frequency occurred at this time. Grooming, scent-marking, olfactory inspections and some other behaviours did not alter significantly in either sex during the ovarian cycle.  相似文献   
17.
Needle biopsy of renal allografts: comparison of two techniques   总被引:2,自引:0,他引:2  
Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.  相似文献   
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The biomedical model that has long been central to medical practice is gradually being expanded to a broader biopsychosocial model. Relationship-building skills commensurate with the new paradigm need to be understood by educators and taught to medical practitioners. The person-centered, or humanistic, model of psychologist Carl Rogers provides a theoretical approach for the development of effective biopsychosocial relationships. The Barrett-Lennard Relationship Inventory (BLRI) was developed in 1962 as an assessment instrument for the person-centered model. In this article, the person-centered model and the use of the BLRI as an assessment instrument of this model are discussed. Current and potential uses of the BLRI are explored.  相似文献   
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