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21.
D Kirby 《The Journal of school health》1986,56(7):289-291
The lack of needed health care and the number of unintended pregnancies among young people in the U.S. have caused many schools to increase the scope of their health services in the past 2 decades. Beginning in the 1970s, some communities also responded to that need with more comprehensive health clinics. By August of 1986, the Support Center for School-Based Clinics at the Center for Population Options had identified more than 60 comprehensive clinics in the U.S. having the characteristics identified in this discussion. Locations of these clinics include Chicago, Kansas City, St. Paul, and West Dallas. These comprehensive health centers provide direct comprehensive primary care, prescribe and/or dispense medications, provide family planning and other services related to sexuality, commonly are operated by established medical providers rather than the schools, and are staffed by nurse practitioners and physicians. These comprehensive centers represent the next step in an evolutionary process of improving adolescent health care in the schools. The Support Center for School-Based clinics collected questionnaire data on the clinics. Most of the comprehensive clinics offer a variety of services. All of the clinics facilitate family planning and minimally provide counseling about sexual activity and birth control, make referrals, and engage in follow-up activities. Direct management of all but 1 clinic is by nonschool agencies. Most clinics strongly encourage patients to discuss any health problems as well as sexual decisions with their parents. Virtually all clinics obtain written consent from parents before students receive medical services. According to the providers, the location of clinics in schools offers many advantages, including: each clinic is accessible and familiar; because the clinic is strictly an adolescent clinic, it can hire staff that like adolescents and are skilled at working with adolescents; many clinic services are consolidated; and the clinics can treat the whole person in an integrated way. Clinic records show the percentage of female students receiving family planning services to have increased from 0% to about 27%, and the 12-month and 24-month contraception continuation rates were 93% and 82% (based on 1982). 相似文献
22.
R J Chenery A Ayrton H G Oldham P Standring S J Norman T Seddon R Kirby 《Drug metabolism and disposition》1987,15(3):312-317
Diazepam metabolism has been investigated in cultured hepatocytes from rat, rabbit, dog, guinea pig, and man. The metabolite profile obtained by HPLC analysis of the culture medium indicated that substantial differences exist corresponding to known species differences in the metabolite profile of diazepam in vivo. These differences were attributed to a combination of the rate at which a metabolite was formed and the rate at which it is removed from the medium by further metabolism. The intrinsic clearance of nordiazepam in hepatocytes from each of the species exhibited the most marked species variation (rat much greater than guinea pig greater than rabbit greater than human greater than dog). Species that exhibited a high intrinsic clearance for nordiazepam were also those species that exhibited significant hydroxylation at the 4'-site of the molecule. The disappearance of diazepam was rapid in rat, dog, and guinea pig hepatocytes, but slow in human hepatocytes. Moreover, rat and human hepatocytes exhibited different saturability of diazepam clearance with respect to diazepam concentration accounting, at least in part, for the different rates of diazepam metabolism in the different species. These results support the value of hepatocytes in drug metabolism studies and especially in studies of species differences in metabolism. 相似文献
23.
N A Kirby 《The Nursing clinics of North America》1989,24(1):179-191
Persons with quadriplegia resulting from disease or trauma have an array of disabling impairments that involve virtually every body system. During the rehabilitation process, each impairment is addressed. This article presents alternatives in three areas: respiration, communication, and environmental control. The importance of tailoring strategies to the individual is emphasized throughout. Appropriate rehabilitation of the person with high quadriplegia goes beyond maintenance of life and health. An interdisciplinary team that includes the patient unites dreams, knowledge, skills, and technology so that the patient has the possibility of noninstitutional living, major control over his or her own destiny, some autonomy, and participation in a full spectrum of life activities. As Maddox noted: "Life is a fragile, fleeting thing, under any circumstances, and living it can be comic or tragic, weird or wonderful--regardless of one's motor limitations." 相似文献
24.
A simple, relatively rapid silver impregnation stain has been found to stain Legionella pneumophila effectively in paraffin-embedded tissue sections while permitting visualization of histological detail. It may also be used to stain the organism in body fluids. The stain is not specific and thus must be confirmed by direct fluorescent-antibody technique or culture, but, in the absence of other bacilli demonstrable by Gram or other stain, visualization of typical bacillary forms in a patient with illness compatible with Legionnaires disease provides strong presumptive evidence supporting this diagnosis. 相似文献
25.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
26.
27.
The cardiac neural crest is located in a transitional area on the neuraxis between trunk and cephalic regions and gives rise to both the dorsolateral and ventrolateral crest cell populations. Around stage 18 of chick development, a mass of E/C8+ cells surrounds the postotic pharyngeal arches and forms a crescent-shaped arch, termed the circumpharyngeal ridge. Using immunohistochemistry and quail-chick chimeras, it was determined that the E/C8+ cell mass located in the circumpharyngeal ridge derives from the dorsolateral component of the cardiac neural crest. The ventrolateral cell population of the cardiac crest is located more medially and shows long-persistent HNK-1 immunoreactivity dorsolateral to the foregut. The crest cells that populate the gut arise from the caudal portion of the circumpharyngeal crest and are always located caudal to the caudalmost pharyngeal ectomesenchyme. Circumpharyngeal crest cells continuously populate the pharyngeal arch ectomesenchyme and enteric nervous system on the lateral side of the foregut wall, as well as the hypoglossal pathway which develops within the ventral portion of the circumpharyngeal ridge. E/C8 and HNK-1 immunoreactivity are associated with the cells migrating via the dorsolateral (circumpharyngeal) and ventrolateral pathways, respectively, with one exception: there is a population of putative crest cells along the proximal course of the vagal intestinal branch that shows both immunoreactivities around stage 20. Dil labeling of the cells in the circumpharyngeal ridge suggests that the cells are contributed from the circumpharyngeal ridge to this population. Thus, the distribution of the circumpharyngeal crest cells and their derivatives coincides with the peripheral branch distribution of the cranial nerves IX, X, and XII, whose development is selectively affected in the absence of the cardiac neural crest, the source of the circumpharyngeal crest.© Willey-Liss, Inc. 相似文献
28.
Renal allograft rejection: induction and function of adhesion molecules on cultured epithelial cells.
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Y Lin J A Kirby K Clark B K Shenton J L Forsythe G Proud R M Taylor 《Clinical and experimental immunology》1992,90(1):111-116
The interaction of graft-infiltrating immune cells with donor parenchymal cells is an important early event in allograft rejection. This binding is stabilized by interaction of antigen-independent 'adhesion' molecules expressed on the two cell types. As the level of expression of these molecules can be altered during inflammation, a series of experiments was performed to examine the effects of the inflammatory cytokines interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) on adhesion molecules expressed by cultured human renal tubular epithelial cells. These cells constitutively expressed ICAM-1 and LFA-3. Incubation with IFN-gamma increased expression of ICAM-1 but had no significant effect on expression of LFA-3 (P greater than 0.05). Incubation with TNF-alpha increased expression of both ICAM-1 and LFA-3; IFN-gamma synergized with TNF-alpha to further augment expression of these molecules. Peripheral blood lymphocytes (PBL) showed an enhanced binding to allogeneic renal epithelial cell monolayers which had been pretreated with IFN-gamma or TNF-alpha. MoAbs specific for ICAM-1 or its ligand LFA-1 inhibited adhesion of PBL to either IFN-gamma- or TNF-alpha-pretreated renal cells. By contrast, antibodies specific for LFA-3 or its ligand CD2 only significantly blocked PBL adhesion to renal cells which had been pretreated with TNF-alpha. Combination of antibodies specific for multiple components of the adhesion systems produced greater inhibition of adhesion than was produced by any single MoAb. These results suggest that the inflammatory cytokines IFN-gamma and TNF-alpha up-regulate expression of functional ICAM-1 and LFA-3 molecules which can augment the binding of potentially graft-damaging lymphoid cells to renal tubular epithelial cells. 相似文献
29.
Patricia Y. Fechner Kirby D. Smith Ethylin Wang Jabs Claude J. Migeon Gary D. Berkovitz 《American journal of medical genetics. Part A》1992,42(6):807-812
We evaluated a patient with partial gonadal dysgenesis including a right dysgenetic testis and a left streak gonad with rudimentary fallopian tube and uterus. She had ambiguous external genitalia and was raised female. Although her height is normal (25th centile at age 12 years), she has some findings of Ullrich–Turner syndrome. Her karyotype was reported to be 46, X, + marker; subsequent molecular investigations showed the marker to be the short arm of the Y chromosome. Genomic DNA, isolated from leukocytes of the patient and her father, was digested with a variety of restriction endonucleases and subjected to Southern blot analysis. A positive hybridization signal was obtained with probes for the short arm of the Y chromosome (pRsY0.55, SRY, ZFY, 47Z, pY-190, and YC-2) in DNA from the patient, indicating the presence of most if not all of the short arm, while long arm probes (HinfA and pY3.4) indicated that at least 75% of the long arm of the Y chromosome was missing. The gene responsible for testicular determination (TDF) is on the distal portion of the short arm of the Y chromosome; Yq has no known influence on sex determination. Hence, the deletion of the long arm of the Y chromosome cannot explain the gonadal dysgenesis in this patient. One explanation for the gonadal dysgenesis and Ullrich–Turner phenotype in the patient could be undetected 45, X/46,X, + marY mosaicism but no such mosaicism was observed in peripheral lymphocytes. Several investigators have suggested the presence of an “anti-Turner” gene near TDF. Hence it is possible that the clinical phenotype in our patient results from a Y chromosomal defect in sequences flanking TDF, which reduces the function of both TDF and the “anti-Turner” genes. 相似文献
30.