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排序方式: 共有724条查询结果,搜索用时 15 毫秒
1.
Lonnie Embleton Juddy Wachira Allan Kamanda Violet Naanyu David Ayuku 《Culture, health & sexuality》2016,18(3):337-348
Street-connected youth in Kenya are a population potentially at risk of HIV transmission, yet little is known about their perceptions and experiences of sexually transmitted infections (STIs), despite their living in an HIV endemic region. We sought to elucidate the language and sociocultural factors rooted in street life that impact on street-connected young people’s knowledge of and perceptions about the prevention and transmission of STIs, and their diagnosis and treatment, using qualitative methods in western Kenya. We conducted a total of 25 in-depth interviews and 5 focus-group discussions with 65 participants aged 11–24 years in Eldoret, Kenya. Thematic analysis was conducted and data were coded according to themes and patterns emergent until saturation was reached. In general, street-connected young people knew of STIs and some of the common symptoms associated with these infections. However, there were many misconceptions regarding transmission and prevention. Gender inequities were prominent, as the majority of men described women as individuals who spread STIs due to unhygienic practices, urination and multiple partners. Due to misconceptions, gender inequity and lack of access to youth-friendly healthcare there is an urgent need for community-based organisations and healthcare facilities to introduce or augment their adolescent sexual and reproductive health programmes for vulnerable young people. 相似文献
2.
Dinesh Rakheja Payal Kapur Mai P. Hoang Lonnie C. Roy Michael J. Bennett 《Medical hypotheses》2005,65(6):681
Mammalian fatty acid synthase (FASE) overexpression has been shown in a number of human malignancies including colonic adenocarcinoma. Since FASE synthesizes only saturated fatty acids, we hypothesized that cancer cells have a greater proportion of long-chain saturated fatty acids. We studied and found an unequivocal increase in saturated C18 fatty acid (stearic acid) in colonic adenocarcinoma compared to adjacent normal colonic mucosa. The increase is even more striking when measured as a ratio of stearic acid to the unsaturated C18 fatty acids (oleic acid and linoleic acid). This change in fatty acid composition of the cancer cells should significantly alter their physical and biological properties. The increase in relative proportion of saturated fatty acids should make the cancer cells more susceptible to cryodamage and measurement of fatty acid composition of cancer cells may help individualize the temperature for cryotherapy. Also, the lipid alterations may affect the structure and functions of lipid rafts, which may enable the cancer cells to affect signaling mechanisms such as those involved in cell growth and apoptosis. Dietary or therapeutic interventions targeting lipid rafts may thus be an option for cancer treatment. 相似文献
3.
Three cases of cerebral gigantism, two sibs and their double first cousin, are described in a large inbred family from Israel. Two of the three were observed and diagnosed at birth and two were followed for two years. They all presented the signs and symptoms considered typical of this syndrome, as well as some of the less frequent findings. Generalized oedema and flexion contractures of the feet were observed in two of the three at birth. This has not hitherto been reported in cases of cerebral gigantism, of whom only a few have been observed and diagnosed at birth. Autosomal recessive inheritance is clearly implied in this family. 相似文献
4.
In normal adult rats some germ cells degenerate at several vulnerable steps of spermatogenesis. These are the type A spermatogonia, midpachytene spermatocytes, primary and secondary spermatocytes which degenerate during their respective maturation divisions and step 7 and 19 spermatids. In the present study, these degenerating cells were examined under the electron microscope, and their frequency was determined in toluidine blue stained semithin sections of testes from normal, hypophysectomized (at 5.5 days after operation) and hypophysectomized rats injected with FSH and LH separately or in combination. With the exception of the step 19 spermatids, the degenerating germ cells underwent necrosis in vacuolated spaces delimited by Sertoli cells. In the case of the affected step 19 spermatids, an apical cytoplasmic process of the Sertoli cell initially ensheathed a long segment of their flagellum, and then each degenerating cell was drawn deep in the seminiferous epithelium where it was phagocytozed by the Sertoli cell. Soon after hypophysectomy the incidence of degenerating mid-pachytene spermatocytes, step 7 and 19 spermatids which are present in stages VII or VIII of the cycle of the seminiferous epithelium, increased significantly. In contrast the number of degenerating primary or secondary spermatocytes during the meiotic divisions seen in stage XIV of the cycle or of any other germinal cell was not significantly modified. While the injection of FSH alone had no influence on the number of degenerating cells in hypophysectomized rats, injections of LH at the two doses administered (0.7 μg or 20 μg) reduced significantly the number of degenerating cells seen in stages VII-VIII of the cycle; combined injections of FSH and LH (20 μg) reduced the number of these degenerating cells to the normal low values. Thus it appeared that the mid-pachytene spermatocytes and the step 7 and 19 spermatids, all present in the adluminal compartment of the seminiferous epithelium in stages VII or VIII of the cycle, were more sensitive to the presence of absence of gonadotropic hormones than the other germ cells present in the seminiferous epithelium. 相似文献
5.
Chen E Zeltzer LK Bentler PM Byrne J Nicholson HS Meadows AT Mills JL Haupt R Fears TR Robison LL 《Journal of health psychology》1998,3(1):23-38
To determine the pathways between treatment intensity (age at diagnosis, dosage of chemotherapy [intrathecal methotrexate; IT-MTX] and cranial radiation [CRT]) and various psychosocial outcomes, review of medical records and structured interviews were carried out in 510 adult survivors of childhood leukemia. Structural equation modeling revealed that higher treatment intensity during childhood (indicated by treatment with high-dose CRT, low-dose IT-MTX, and adjusted by younger age at diagnosis) predicted more health- compromising behaviors as adults through lower educational achievement. Additionally, higher childhood treatment intensity predicted current negative mood both directly and via changes in perceived limitations. The present study's findings suggest that higher treatment intensity during childhood may serve as a risk factor for adult survivors' health-compromising behaviors through neuropsychological deficits that arise from cancer treatment. 相似文献
6.
Lonnie Russell 《Developmental dynamics》1977,148(3):301-312
Desmosome-like junctions between Sertoli cells and germ cells (spermatogonia, spermatocytes and non-elongate spermatids) were observed in the adult rat testis. At all levels, certain features were characteristic of this relationship, the most prominent being a densification of the subsurface aspect of the plasma membranes of each cell. The Sertoli cell counterpart demonstrated an abundance of cytoplasmic fibrils which converged on the density, but no such feature was evident in the germ cell counterpart. The width of the intercellular space was variable, ranging in some regions from approximately 3–5 nm, to other regions of approximately 14–18 nm, the latter being representative of most areas of contact. A poorly represented, and often discontinous, intermediate dense line was observed in the intercellular space. Hypertonic fixative solutions containing dextrose were utilized to provoke tissue shrinkage and exaggeration of the intercellular space within the basal compartment of the testis. Cell separation was evident over most regions of the cells, except where desmosome-like contacts were present. Forces transmitted from one cell to another at desmosome-like contacts resulted in tearing of cellular fragments, while junctional regions of both cells remained intact. These observations indicate that desmosome-like junctions are strong adhesive sites between germ cells and Sertoli cells. 相似文献
7.
Severe combined immunodeficiency with B lymphocytes: in vitro correction of defective immunoglobulin production by addition of normal T lymphocytes. 总被引:3,自引:2,他引:3
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R C Seeger R A Robins R H Stevens R B Klein D J Waldman P M Zeltzer S W Kessler 《Clinical and experimental immunology》1976,26(1):1-10
A 6 1/2-month-old male with severe combined immunodeficiency (SCID) had a low percentage and number of T cells (11%; 241/mm3) and a high percentage and number of B cells (52%; 1187/mm3) and null cells (37%; 868/mm3). In vitro studies were performed to determine if this child's primary defect involved differentiation of both T and B lymphocytes or if failure of B lymphocytes to differentiate into immunoglobulin producing cells was secondary to T lymphocyte abnormalities. Immunoglobulin production by lymphocytes in response to polyclonal mitogens (pokeweed mitogen and foetal calf serum) was measured by pulse-labelling cells with 3H-leucine and then precipitating cytoplasmic and secreted immunoglobulins with polyvalent anti-human immunoglobulin and S. aureus (Cowan strain I) protein A. The patient's lymphocytes did not synthesize immunoglobulins in vitro in response to mitogens. They did not suppress synthesis of immunoglobulins by normal lymphocytes. However, addition of normal purified T cells, which themselves did not synthesize immunoglobulins, enabled the patient's B lymphocytes to become immunoglobulin synthesizing and secreting cells. Gamma, mu, and light chains were secreted. This suggests that the primary abnormality was in the T-cell axis at the level of lymphoid stem cells or prothymocytes and that failure of B lymphocytes to become immunoglobulin-producing cells was secondary to this defect. 相似文献
8.
Smita Bhatia Wendy Landier Jacqueline Casillas Lonnie Zeltzer 《European journal of pediatrics》1995,154(9):757-791
Abstracts
15th Scientific Congress of the European Society for Pediatric Hematology and Immunology (ESPHI) Bingen, Germany, 23–26 August 1995 相似文献9.
Brian J. Cuffel Ph.D. Lonnie Snowden Ph.D. Mary Masland M.S.P.H. Giorgio Piccagli Ph.D. 《Community mental health journal》1996,32(2):109-124
The movement towards managed care in the public mental health system has surpassed efforts to develop a systematic literature concerning its theory, practice, and outcome. In particular little has been written about potential challenges and difficulties in translating managed care systems from their origins in the private sector to the delivery of public sector mental health services. This paper provides an overview of managed care definitions, organizational arrangements, administrative techniques, and roles and responsibilities using a theoretical framework adopted from economics referred to as principal-agent theory. Consistent with this theory, we assert that the primary function of the managed care organization is to act as agent for the payor and to manage the relationships between payors, providers, and consumers. From this perspective, managed care organizations in the public mental health system will be forced to manage an extremely complex set of relationships between multiple government payors, communities, mental health providers, and consumers. In each relationship, we have identified many challenges for managed care including the complexity of public financing, the vulnerable nature of the population served, and the importance of synchronization between managed care performance and community expectations for the public mental health system. In our view, policy regarding the role of managed care in the public mental health system must evolve from an understanding of the dynamics of government-community-provider-consumer agency relationships.Mary Masland, M.S.P.H., is Research Associate, Institute for Mental Health Services Research.Giorgio Piccagli, Ph.D., is Affiliated Investigator, Institute for Mental Health Service Research.This work was supported by the National Institute of Mental Health funded Center for Research on the Organization and Financing of Care for the Severely Mentally Ill (P50-MH43694). 相似文献
10.
Correlation of neurosurgical subspecialization with outcomes in children with malignant brain tumors
Albright AL Sposto R Holmes E Zeltzer PM Finlay JL Wisoff JH Berger MS Packer RJ Pollack IF 《Neurosurgery》2000,47(4):879-85; discussion 885-7
OBJECTIVE: This study was performed to evaluate the association between the type of neurosurgeon (general or pediatric) and either the extent of tumor removal or the frequency of complications in children undergoing malignant brain tumor resections. METHODS: Data were analyzed from three recent Children's Cancer Group studies: two on medulloblastomas/primitive neuroectodermal tumors and one on malignant gliomas. Neurosurgeons were classified as general neurosurgeons, as designated pediatric neurosurgeons in their institutions, or as members of the American Society of Pediatric Neurosurgeons (ASPN), which requires pediatric neurosurgical experience and practice standards. RESULTS: Data forms from 732 children were analyzed; 485 were from children with medulloblastomas/primitive neuroectodermal tumors, and 247 were from children with malignant gliomas. Operations were performed by 269 neurosurgeons, including 213 general neurosurgeons, 29 designated pediatric neurosurgeons, and 27 ASPN members. The mean number of operations per surgeon was 1.8, 4.9, and 7.6 for general neurosurgeons, designated pediatric neurosurgeons, and ASPN members, respectively. There was a significant relationship between the extent of tumor resection or the amount of residual tumor and the type of neurosurgeon. Designated pediatric neurosurgeons and ASPN members were more likely to remove more than 90% of the tumor and to leave less than 1.5 cc of residual tumor than were general neurosurgeons (P<0.05). In these studies, the probability of extensive tumor removal correlated with the number of operations the neurosurgeon performed (P<0.01). Neurological complications occurred in the following proportion of cases: general neurosurgeons, 23%; designated pediatric neurosurgeons, 32%; and ASPN members, 18%. CONCLUSION: Pediatric neurosurgeons are more likely than general neurosurgeons to extensively remove malignant pediatric brain tumors. In these tumors, extent of removal has been demonstrated to influence survival. 相似文献