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2.
Frank L Cole Laura L Kuensting Susan Maclean Cynthia Abel Joyce Mickanin Patty Brueske Mary Ellen Wilson Maureen Rehwaldt 《Journal of emergency nursing》2002,28(5):414-419
INTRODUCTION: Very little is known about clinical nurse specialists and nurse practitioners (advance practice nurses [APNs]) who practice in emergency care settings. The Advanced Practice Committee of the ENA sought to determine a profile of these individuals. METHODS: Surveys were distributed to all registrants at 2 ENA conferences and posted on the ENA Web site. This survey asked 17 questions concerning the demographic characteristics of the APN respondents (eg, education, experience, certification, state recognition, and practice area). The survey was completed by 166 APNs. RESULTS: APNs had considerable experience as ED registered nurses before becoming an APN. They obtained their APN education at the master's degree or post-master's degree level. State recognition was required for 89.2% of the APNs. The majority of APNs (61.4%) obtained their certification through the American Nurses Credentialing Center. Nurse practitioners were predominantly family nurse practitioners (43%), and clinical nurse specialists were either critical care clinical nurse specialists (8.9%) or had other certifications (5.9%). APNs provided services in both the main emergency department and the fast track (45.7%) and were relatively new to their role as an APN. DISCUSSION: Consistent with current educational and certification requirements, the vast majority of APNs held a master's degree. Although relatively new to their role as APNs in emergency care, they were nonetheless very experienced as ED registered nurses. The majority of APNs were certified, even though that is not required for practice in all states. Continued research is needed to identify the most effective utilization of APNs, document their contributions to patient care outcomes, and develop strategies to meet their educational and practice needs. 相似文献
3.
Effects of exercise training on men seropositive for the human immunodeficiency virus-1. 总被引:1,自引:0,他引:1
L W Rigsby R K Dishman A W Jackson G S Maclean P B Raven 《Medicine and science in sports and exercise》1992,24(1):6-12
We examined the effects of chronic exercise on fitness and immune status in Caucasian males (34.9 +/- 5.6 yr) diagnosed by Western blot as seropositive for the HIV-1 virus. The exercise regimen involved 12 wk of 1 h sessions 3 d.wk: 20 min of cycle exercise at 60-80% HRreserve was followed by 35 min of strength and flexibility training. After matching subjects on health status (modified Walter Reed criteria), subjects (N = 37) were randomly assigned to exercise or a counseling control condition. Changes in strength, responses to the YMCA cycle test, and serum lymphocytes were tested by MANOVA in a condition (exercise or counseling)-by-time (pretest, posttest) design with repeated measures on time. Results indicated significant (P less than 0.001) group-by-time interactions for strength (N.m) (chest press and leg extension) and for HR (beats.min-1) and total time (TT) on the cycle test at 150 W. Strength and TT increased and HR decreased in the exercise condition, while control subjects did not change. Total leukocyte, lymphocyte, CD4+, and CD8+ cell counts, and the CD4+/CD8+ ratio were statistically unchanged for each condition. We conclude that HIV-1+ men, including those symptomatic for AIDS-related complex, can experience significant increases in neuromuscular strength and cardiorespiratory fitness without changes in lymphocyte phenotypes or clinical diagnosis when the exercise regimen is prescribed and monitored in accordance with ACSM guidelines for healthy adults. 相似文献
4.
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
5.
Wilson R Moore J Jenkins C Miller H Maclean MA McInnes IB Walker JJ 《Human reproduction (Oxford, England)》2003,18(7):1529-1530
BACKGROUND: Immunological abnormalities have been found in pregnant women with a history of recurrent miscarriage. This study compared interleukin-2 receptor (IL-2R) levels in non-pregnant women with a history of recurrent miscarriage with those found in serum from a non-pregnant group with no such history. METHODS: Group 1 comprised 49 non-pregnant women with a history of recurrent miscarriage (at least three consecutive miscarriages). Group 2 comprised 22 non-pregnant women with no history of miscarriage. Serum IL-2R levels were measured in all patients. RESULTS: The results obtained showed that although all women were not pregnant at the time of sampling, IL-2R levels were significantly higher in women in Group 1 compared with those in Group 2 (1589 +/- 1289 versus 1082 +/- 823 pg/ml; P < 0.05). Follow-up data were available for 21 women from Group 1. The next pregnancy ended successfully for 14 of these women, while seven miscarried again. The IL-2R levels obtained pre-pregnancy were not significantly different between the two groups (1480 +/- 910 versus 1356 +/- 716 pg/ml). CONCLUSION: This study has shown that non-pregnant women with a history of recurrent miscarriage have raised IL-2R levels. These increased pre-pregnancy IL-2R levels did not necessarily predict miscarriage for the next pregnancy. 相似文献
6.
N E Morton D C Rao H Lang-Brown C J Maclean R D Bart R Lew 《Journal of medical genetics》1977,14(1):1-9
This reanalysis of a classic survey leads to inferences about design of genetic studies, resolution of heterogeneity, and the role of autosomal and sex-linked genes in mental retardation, which is no longer refractory to segregation analysis. By discriminating between sociofamilial and biological types we estimate that at least 351 autosomal loci can produce mental retardation, with an inbred load of 0.83 detrimental equivalents and a mutation rate of 0.008 per gamete, or less than 2.4 X 10(-5) per locus. The distribution of probands was estimated as: 7 per cent medical, 60 per cent sociofamilial, and 33 per cent biological. Simple genetic mechanisms account for virtually all the biological category. Within the sociofamilial group cultural inheritance and polygenes could not be resolved. 相似文献
7.
c-Myc is essential for vasculogenesis and angiogenesis during development and tumor progression 总被引:13,自引:0,他引:13
Baudino TA McKay C Pendeville-Samain H Nilsson JA Maclean KH White EL Davis AC Ihle JN Cleveland JL 《Genes & development》2002,16(19):2530-2543
c-Myc promotes cell growth and transformation by ill-defined mechanisms. c-myc(-/-) mice die by embryonic day 10.5 (E10.5) with defects in growth and in cardiac and neural development. Here we report that the lethality of c-myc(-/-) embryos is also associated with profound defects in vasculogenesis and primitive erythropoiesis. Furthermore, c-myc(-/-) embryonic stem (ES) and yolk sac cells are compromised in their differentiative and growth potential. These defects are intrinsic to c-Myc, and are in part associated with a requirement for c-Myc for the expression of vascular endothelial growth factor (VEGF), as VEGF can partially rescue these defects. However, c-Myc is also required for the proper expression of other angiogenic factors in ES and yolk sac cells, including angiopoietin-2, and the angiogenic inhibitors thrombospondin-1 and angiopoietin-1. Finally, c-myc(-/-) ES cells are dramatically impaired in their ability to form tumors in immune-compromised mice, and the small tumors that sometimes develop are poorly vascularized. Therefore, c-Myc function is also necessary for the angiogenic switch that is indispensable for the progression and metastasis of tumors. These findings support the model wherein c-Myc promotes cell growth and transformation, as well as vascular and hematopoietic development, by functioning as a master regulator of angiogenic factors. 相似文献
8.
Familial prevalence of uterine fibroids is associated with distinct clinical and molecular features 总被引:3,自引:0,他引:3
BACKGROUND: Although uterine fibroids are very common, their pathogenesis and clinical behaviour are poorly understood. Since they may be prevalent in some families, we investigated whether such a prevalence was associated with distinctive clinical and molecular features. METHODS: A case-control questionnaire study of 300 multi-ethnic women with uterine fibroids at a London university hospital was undertaken, with review of case notes and immunohistochemical determination of vascular endothelial growth factor (VEGF-A) in fibroids. RESULTS: When compared with families with sporadic fibroids, familial prevalence of fibroids was associated with a higher incidence of abdominal swelling (59.1% versus 41.6%; P=0.037), menorrhagia (84.4% versus 51.9%; P=0.042), dysmenorrhoea (64.4% versus 46.3%; P=0.004), dyspareunia (43.2% versus 27.9%; P=0.012) and family history of cancers (52.3% versus 32.4%; P<0.01). The fibroids were also more multiple (mean +/- SEM: 7 +/- 0.86 versus 3 +/- 0.42; P<0.011) and strong VEGF-A expression in fibroids was more common in the familial group (64% versus 28%). Racial distribution was the same in both groups (blacks 49%, whites 33.4%, others 18.6%). CONCLUSIONS: Familial prevalence of uterine fibroids is associated with distinct clinical and molecular features that differ from those found when fibroids occur sporadically in families. 相似文献
9.
Ronald N. Maclean William K. Prater Carmen B. Lozzio John M. Opitz 《American journal of medical genetics. Part A》1983,14(2):373-380
We report on an infant with broad and severely angulated short femora as the most salient manifestation of a generalized skeletal dysplasia. Other findings include congenital bowing of other long bones, narrow thorax, platyspondyly, micrognathia, and skin dimples. A marked improvement of the bowing and of the irregular flare of the metaphyses was noted over a period of 6 mo. Congenital bowing of long bones can be an isolated finding or associated with other anomalies, so the purpose of reporting all cases is important for further nosologic and pathogenetic elucidation. Because of the severity of the femoral involvement, the condition has been called kyphomelic dysplasia. It may be an autosomal recessive trait. recessive trait. 相似文献
10.
Advances in liposome technology over the last decade has seen the development of stealth liposomes for drug delivery and cationic liposomes for gene delivery. Many of these liposome formulations are now in clinical trials for the treatment of a variety of malignancies. Whilst some clinical efficacy has been demonstrated, the goal of specific tumor targeting is yet to be attained. For this reason, antibodies have been attached to the surface of liposomes to produce immunoliposomes. These liposomes have shown preferential binding to specific tumor cells in animal models. The construction of the immunoliposome, and in particular the optimal method of antibody coupling to its surface is, however, yet to be determined. Despite these difficulties, immunoliposomes have demonstrated anti-tumor properties, both in vitro and in vivo, and show great promise as targeted delivery vehicles for the treatment of cancer. 相似文献