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131.
Dominika Seidman Marielle Cavrois Joan F. Hilton Nadia R. Roan Sarah Averbach Margaret Takeda Eric Chang Nandhini Raman Ruth Greenblatt Barbara L. Shacklett Karen Smith-McCune 《Contraception》2021,103(1):44-47
IntroductionEx vivo fusion assays offer an efficient method for studying HIV-1 entry associated with contraceptive use and pregnancy outside of cohort studies of HIV-1 incidence.MethodsWe measured ex vivo HIV-1 fusion to cervical or endometrial immune cells from three groups of women: pregnant, non-pregnant not using hormonal or intrauterine contraception, and using depot medroxyprogesterone acetate (DMPA).Results and conclusionsThere was no excess susceptibility to HIV-1 fusion of cells from pregnant women or DMPA users compared to controls. Although the number of target cells in endometrium was higher in DMPA users compared to controls, HIV-1 fusion was lower.ImplicationsIn ex vivo assays, HIV-1 showed no enhanced fusion to cervical immune cells from pregnant women or DMPA users compared to controls, and lower fusion to endometrial immune cells from DMPA users. This assay is useful for studying hormonal and contraceptive effects on HIV-1 entry into reproductive tract immune cells. 相似文献
132.
133.
Ultrastructural characteristics of primordial germ cells and their amoeboid movement to the gonadal ridges in the tammar wallaby 总被引:3,自引:0,他引:3
The primordial germ cells (PGCs) of tammar wallaby fetuses are large cells with large nuclei. The cytoplasm of the PGCs contains
characteristic spherical mitochondria and abundant ribosomes that make the cyoplasm appear dense. No permanent junctional
complexes between PGCs and somatic cells were observed, and there were few cytoplasmic inclusions. The majority of migrating
PGCs were observed outside the gonad in the dorsal mesentery and in the tissues adjacent to the gonad. The migrating PGCs
have many finger-like, blunt pseudopodia, within which microfilament bundles are observed. The numerous dumbell-like PGCs
with polarised cytoplasm suggest that the PGCs of this marsupial move to the gonadal ridges by amoeboid movement, but once
the PGCs reach the gonadal ridge, they assume their more characteristic ovoid shape.
Accepted: 10 January 1997 相似文献
134.
135.
Eleanor J. Reimer Carolyne J. Montgomery Joan C. Bevan Pamela M. Merrick Derek Blackstock Vladan Popovic 《Journal canadien d'anesthésie》1993,40(10):927-933
Propofol anaesthesia may reduce postoperative emesis. The purpose of this study was to compare the incidence of emesis after propofol anaesthesia with and without nitrous oxide, compared with thiopentone and halothane anaesthesia, in hospital and up to 24 hr postoperatively, in outpatient paediatric patients after strabismus surgery. Seventy-five ASA class I or II, unpremedicated patients, aged 2–12 yr were randomly assigned to one of three groups: Thiopentone, 6.0 mg · kg? 1 iv induction followed by halothane and N2O/O2 for maintenance (T/H); propofol for induction, followed by propofol and oxygen for maintenance (P/O2); and propofol for iv induction, followed by propofol infusion and N2O/O2 for maintenance (P/N2O). All received vecuronium, controlled ventilation, and acetaminophen pr. Morphine was given as needed for postoperative analgesia. There were no differences in age, weight, number of eye muscles operated upon, duration of anaesthesia or surgery. The P/N2O group (255 ± 80 μg· kg? 1· min? 1) received less propofol than the P/O2 group (344 ± 60 μg · kg? 1· min? 1) (P ≤ 0.0001) and had shorter extubation (P < 0.001) and recovery (P < 0.01) times. Emesis in the hospital, in both the P/N2O (4.0%) and P/O2 group (4.0%) was less than in the T/H group (32%) (P < 0.01). Antiemetics were required in four patients in the T/H group (16.0%). Overall emesis after surgery was not different among the groups: T/H (48%), P/O2 (28%) and P/N2O (42%). The use of propofol anaesthesia with and without N2O decreased only early emesis. This supports the concept of a short-acting, specific antiemetic effect of propofol. 相似文献
136.
Two sets of experiments were carried out to compare the effects of fenfluramine and fluoxetine on consummatory and operant behaviour. In food-deprived rats allowed access to a 35% sucrose solution, an initial period of sucrose consumption was followed by a short period of grooming and exploratory behaviour, later superceded by resting. This behavioural satiety sequence was advanced by fluoxetine, but disrupted bydl-fenfluramine, which suppressed post-prandial resting, even at sub-anorectic doses. Fluoxetine also elicited resting behaviour following water drinking. However, this did not appear to be a non-specific sedative effect, since fluoxetine increased post-prandial grooming. In rats performing on random interval schedules of food reinforcement, fluoxetine caused proportionally greater decreases in responding on a reinforcement-lean schedule (RI-300s), as compared to a reinforcement-rich schedule (RI-7.5s); this effect is similar to that of a reduction in level of food deprivation. By contrast, fenfluramine reduced responding equally on both schedules. In both paradigms, the effects of fluoxetine were compatible with an increase in postprandial satiety, but the effects of fenfluramine were not. 相似文献
137.
Yang Weilian Barth Rolf F. Rotaru Joan H. Moeschberger Melvin L. Joel Darrel D. Nawrocky Marta M. Goodman Joseph H. 《Journal of neuro-oncology》1997,33(1-2):59-70
Boronophenylalanine (BPA) has been used for boron neutron capture therapy (BNCT) of brain tumors in both experimental animals and humans. The purpose of the present study was to determine if the efficacy of BNCT could be enhanced by means of intracarotid (i.c.) injection of BPA with or without blood-brain barrier disruption (BBB-D) and neutron irradiation using a rat brain tumor model. For biodistribution studies, F98 glioma cells were implanted stereotactically into the brains of Fischer rats, and12 days later BBB-D was carried out by i.c. infusion of 25% mannitol (1.373 mOsmol/ml), followed immediately by i.c. administration of 300, 500 or 800 mg of BPA/kg body weight (b.w.). At the 500 mg dose a fourfold increase in tumor boron concentration (94.5 g/g) was seen at 2.5 hours after BBB-D, compared to 20.8 g/g in i.v. injected animals. The best composite tumor to normal tissue ratios were observed at 2.5 hours after BBB-D, at which time the tumor: blood (T: Bl) ratio was10.9, and the tumor: brain (T: Br) ratio was 7.5, compared to 3.2 and 5.0 respectively for i.v. injected rats. In contrast, animals that had received i.c. BPA without BBB-D had T: Bl and T: Br ratios of 8.5 and 5.9, respectively, and the tumor boron concentration was 42.7g/g. For therapy experiments, initiated 14 days after intracerebral implantation of F98 glioma cells, 500 mg/kg b.w. of BPA were administered i.v. or i.c. with or without BBB-D, and the animals were irradiated 2.5 hourslater at the Brookhaven Medical Research Reactor with a collimated beam of thermal neutrons delivered to the head. The mean survival time for untreated control rats was 24 ± 3 days, 30 ± 2 days for irradiated controls, 37 ± 3 days for those receiving i.v. BPA, 52 ± 15 days for rats receiving i.c. BPA without BBB-D, and 95 ± 95 days for BBB-D followed by i.c. BPA and BNCT. The latter group had a 246% increase in life span (ILS) compared to untreated controls and a 124% ILS compared to that of i.v. injected animals. These survival data are the best ever obtained with the F98 glioma model and suggest that i.c. administration of BPA with or without BBB-D may be useful as a means to increase the efficacy of BNCT. 相似文献
138.
Dr Miguel A. Asenjo Lluisa Baré José M. Bayas Andreu Prat Rafel Lledó Joan Grau Lluis Salleras 《European journal of epidemiology》1994,10(5):625-632
The results of the prospective application of Horn's Severity of Illness Index in a teaching hospital during 1987, 1989, and 1990 constitute the basis of the present report. The average overall severity of illness scores for the three years were 1.42 in 1987, 1.65 in 1989, and 1.46 in 1990. Most of the processes evaluated in the three periods showed an overall distribution among severity levels 1 and 2, both overall and when the seven dimensions of the severity of illness index were analyzed. A statistically significant correlation between the overall severity of illness and average length of stay was found for patients in 1989 and 1990. The length of stay differed significantly in the different severity levels. When the four levels of the seven dimensions of the severity of illness index for 1987, 1989, and 1990 were compared, it was observed that figures were not uniformly distributed. There was a statistically significant association between severity of illness for hospital service and pharmacy charges per hospital stay for both 1989 and 1990, as well as a statistically significant inverse relationship between severity of illness and the number of claims per hospital service in both periods of time. Case-mix methods that account for the severity of patients constitute a useful indicator of quality for the management of different hospital services and of the hospital as a whole. 相似文献
139.
Montse Iglesias Rosa M. Soler Dale D. Hunter Joan Ribera Josep E. Esquerda Joan X. Comella 《Journal of neurocytology》1995,24(12):903-915
Summary The purpose of the work reported here is to identify molecular components of the synaptic basal lamina of skeletal muscle fibres which allow recognition of original synaptic sites by regenerating motor axons. We focused on s-larninin and components recognized by the lectinDolichos biflorus agglutinin previously shown to be specifically located at the synaptic basal lamina. We used a cryoculture bioassay in which chick ciliary ganglion neurons grow on rat skeletal muscle cryostat sections. In control cultures, neurites extended over the muscle sections in close association with the muscle cell surface. It was observed that most of the neurites that extended towards the endplate zone and reached an area of 40 m around the neuromuscular junction ceased to grow when they contacted the synaptic site. Masking either lectin receptors or some s-laminin molecule epitopes prior to the culture of neurons alters the behaviour of growing neurites. On sections treated either withDolichos biflorus agglutinin or anti s-laminin monoclonal antibodies (D5 and C4) most of the neurites did not stop their growth at the synaptic regions. Moreover, treating muscle sections withDolichos biflorus agglutinin removed the gradient of substratum affinity around the endplate. These results indicate that the s-laminin andDolichos biflorus agglutinin receptors present on muscle cell surfaces may play a functional role in the interaction of growing neurites with original synaptic sites in the process of neuromuscular regeneration. 相似文献
140.
The family experience of deinstitutionalization: Insights from the closing of Central State Hospital
Eric R. Wright Ph.D. George Avirappattu Ph.D. Joan E. Lafuze Ph.D. 《The journal of behavioral health services & research》1999,26(3):289-304
Since the early 1970s, policy makers and researchers have expressed concern about the potential negative consequences of deinstitutionalization on families. This article summarizes results of a survey of family and lay caregivers of patients discharged from Central State Hospital, which closed in June 1994. The survey was designed to assess the impact of the closing on family members, including their attitudes, caregiving responsibilities, and involvement in the treatment of the patients. Results indicate that family members have mixed feelings about the closure. Family caregivers also reported that they have not been asked to take on significant amounts of the caregiving responsibilities since the clients were moved from the hospital. Family members described a significant reduction in the frequency of contact they had with their loved ones and with professional caregivers since the closure. Implications for behavioral health policy makers considering or planning closing or downsizing long-term care facilities are discussed.An earlier version of this article was presented at the 1997 American Public Health Association Annual Meeting in Indianapolis, Indiana. The analyses and conclusions reported here are the sole responsibility of the authors and do not necessarily reflect the position or opinions of the funding institutions or Indiana University.He is also with the Indiana Consortium for Mental Health Services Research in Bloomington. 相似文献