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71.
The Athletic Prevention Programming and Leadership Education (APPLE) Model: Developing Substance Abuse Prevention Programs
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Alcohol and other drug (AOD) abuse affects every sector of society, and student-athletes are no exception. Because many factors affecting athletes do not affect other students, athletic departments commonly approach prevention through AOD education. Different educational approaches are described in this article, particularly the Athletic Prevention Programming and Leadership Education (APPLE) model. Project APPLE is designed to enable an athletic department to systematically analyze its AOD prevention in seven areas: recruitment practices, expectations and attitudes, education and AOD programs, policies, drug testing, discipline, and referral and counseling. Because athletic trainers often are involved in this process, this article should help them to design more effective AOD programs. 相似文献
72.
Ventromedial hypothalamic lesioned rats maintained at preoperative body weight received an equal number of shocks while emitting significantly fewer responses than controls in a lever-pressing free-operant avoidance paradigm, and performed as well as unoperated animals in lever-pressing and shuttle box (both 1- and 2-way) discriminated avoidance tasks. The failure of VMH lesions to facilitate performance in the 2-way avoidance paradigm was probably the result of a ceiling effect. With the exception of the simple one-way avoidance task, obese lesioned rats were markedly impaired in the acquisition of all active avoidance behavior, but escape behavior was not affected. When tested in a free-operant paradigm, the avoidance performance of well trained lesioned animals varied inversely with body weight. As obese rats displayed lower flinch thresholds to shock than controls and similar levels of activity and responding as lean lesioned animals, it was concluded that their impaired avoidance behavior was not due to changes in sensitivity or mobility. The possible relation to other VMH lesion- and/or obesity-induced deficits is discussed. 相似文献
73.
Involvement of helicase II (uvrD gene product) and DNA polymerase I in excision mediated by the uvrABC protein complex. 总被引:45,自引:8,他引:37
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P R Caron S R Kushner L Grossman 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(15):4925-4929
The bimodal-incision nature of the reaction of UV-irradiated DNA catalyzed by the Escherichia coli uvrABC protein complex potentially leads to excision of a 12- to 13-nucleotide-long damaged fragment. However, the oligonucleotide fragment containing the UV-induced pyrimidine dimer is not released under nondenaturing in vitro reaction conditions. Also, the uvrABC proteins are stably bound to the incised DNA and do not turn over after the incision event. In this communication it is shown that release of the damaged fragment from the parental uvrABC-incised DNA is dependent upon either chelating conditions or the simultaneous addition of the uvrD gene product (helicase II) and the polA gene product (DNA polymerase I) when polymerization of deoxynucleoside triphosphate substrates is concomitantly catalyzed. The product of this multiprotein-catalyzed series of reactions serves as a substrate for polynucleotide ligase, resulting in the restoration of the integrity of the strands of DNA. The addition of the uvrD protein to the incised DNA-uvrABC complex also results in turnover of the uvrC protein. It is suggested that the repair processes of incision, excision, resynthesis, and ligation are coordinately catalyzed by a complex of proteins in a "repairosome" configuration. 相似文献
74.
Length variation of a ribosomal DNA "spacer" region in four chromosomally characterized transitional cell carcinoma cultures was analyzed by restriction endonuclease cleavage and Southern blotting. Cell lines with relative karyotypic conservation, such as UM-UC-2 (modal chromosome number 48, four marker chromosomes) demonstrate little change in the genetically regulated pattern of rDNA spacer length polymorphisms (7.6, 6.7 and 6.0 kilobases) which may be found in normal cells. Cell lines with more aberrant karyotypes, such as UM-UC-3 (modal chromosome number 86, 12 marker chromosomes) and UM-UC-4 (modal number 51, ten marker chromosomes) show fewer ribosomal DNA length variants (7.6, 6.7 kilobases for the former, 7.6 kilobases for the latter), consistent with relaxed constraints on the drive for ribosomal gene homogeneity through inter and intrachromosomal exchange. Uncharacterized rDNA length variants of low copy number were observed in cell lines with many marker chromosomes. Analysis of repetitive DNA structure provides an additional criterion for tumor diagnosis and staging, and a characterized series of tumor cell lines may provide a useful system for understanding repetitive DNA evolution. 相似文献
75.
Matthew M. Clark M.A. John R. Corbisiero M.A. Mary E. Procidano Ph.D. Saul A. Grossman Ph.D. 《Community mental health journal》1984,20(4):262-268
The usefulness of assertive training for elderly psychiatric outpatients was assessed through a quasi-experimental evaluation of a program at a community geriatric facility. Elderly clients are frequently labeled as untreatable and are therefore often denied therapeutic treatment. This study is an example of the potential effectiveness of applying treatment techniques which have been developed with younger populations to a geriatric population. Nineteen clients, aged 50–75, participated in the study, either as participants in the assertion training or as members of a no-treatment control group. The assertion training consisted of 14 semi-weekly sessions, with coaching and feedback provided by the therapists. Assertive behaviors were assessed through self-report, role play and staff ratings of adaptive behaviors of clients. Pre-intervention comparisons between the groups along these dimensions were nonsignificant. However, post-test assessment indicated a significant between group difference in self-reported assertiveness-(t(17)=2.69;p<.05). Dependent t-tests indicated that the experimental group became more assertive (t(9)=2.59;p<.05), but the control group did not. Changes as assessed by role play and staff rating did not reach statistical significance. Results which indicate the potential effectiveness of assertive training with this population are discussed in terms of a specificity conceptualization of assertiveness and implications for assertive training with this population.This paper is based upon their masters' theses. 相似文献
76.
77.
78.
Rapid changes in the expression of a gene encoding a calcium-binding protein in Schistosoma mansoni 总被引:9,自引:0,他引:9
D Ram Z Grossman A Markovics A Avivi E Ziv F Lantner I Schechter 《Molecular and biochemical parasitology》1989,34(2):167-175
Genes expressed in a stage-specific manner may help us understand the molecular events controlling the complex life cycle of schistosomes. cDNA and genomic clones encoding a calcium-binding protein (CaBP) were obtained from cercariae and their sequence determined. The encoded protein (69 amino acids long) shows clear resemblance to the domain structure and organization of CaBP molecules. It contains two typical calcium-binding loops, the distance between which is identical to the length conserved in other CaBP molecules. In addition, the schistosome CaBP shows Ca2+-dependent electrophoretic mobility (increased with Ca2+-ions and decreased with EGTA). Northern blots revealed expression of the CaBP gene in cercariae but not in sporocyst or worm (developmental stages preceding and following cercaria). The preferential expression of this CaBP in the cercaria raises questions as to what cercaria-specific function(s) it performs. The structure of the gene is similar to that in other eukaryotes, and one intron interrupts the coding sequence. The region of the cap site was determined, and there was no evidence of the spliced leader sequence found in the mRNAs of other parasites. The CaBP reveals a rapid change in gene expression, since the mRNA is missing in the parasite residing in infected snails, but is readily detected in cercariae 1 h after shedding. We identified other genes which are turned on (like the CaBP) or shut off within the short period of transition from cercariae in the snail to free-swimming cercariae. 相似文献
79.
The aim of this paper is to examine the determinants of interest rates on tax-exempt hospital bonds. The results highlight the potential and actual roles of Federal and state policy in the determination of these rates. The shift to a Prospective Payment System under Medicare has subsidized the borrowing costs of some hospitals at the expense of others. The selection of underwriters by negotiation rather than by competitive bidding results in higher interest rates. The Federal tax act of 1986 raised the cost of hospital debt by encouraging bond issues to contain call features. 相似文献
80.
Glenn J. Lesser Stuart A. Grossman Susan Eller Eric K. Rowinsky 《Cancer chemotherapy and pharmacology》1995,37(1-2):173-178
Paclitaxel is an important agent in the treatment of many common malignancies. Although the symptomatic peripheral neuropathy caused by this drug is its principal nonhematologic toxicity, little is known about the distribution of paclitaxel within the peripheral or central nervous system following systemic administration. In order to study paclitaxel's distribution in neural and extraneural tissues, adult Sprague-Dawley rats were sacrificed 2 h after a tail vein injection of [3H]-paclitaxel (0.03 mg/kg, 250 Ci/rat). Samples of lung, heart, liver, spleen, kidney, skeletal muscle, brain, spinal cord, dorsal root ganglion, and peripheral nerve were then removed and snap-frozen. These tissues were sectioned at 10 m in a cryostat and exposed to autoradiography film for 2 weeks. The distribution and concentrations of [3H]-paclitaxel in plasma, urine and cerebrospinal fluid were also determined using liquid scintillation spectrometry. [3H]-Paclitaxel concentrations (and organ/plasma concentration ratios) in plasma, urine and cerebrospinal fluid were 2.6 nM (1), 38 nM (15) and 0.7 nM (0.3), respectively. A relatively homogeneous distribution of [3H]-paclitaxel was observed in liver [412 nM (151)], spleen [351 nM (133)], heart [319 nM (117)], lung [268 nM (93)] and muscle [69 nM (26)]. Higher concentrations of [3H]-paclitaxel were noted in the portal triads [869 nM (361)], glomeruli [797 nM (304)], and renal medulla [961 nM (363)], which may reflect biliary excretion and glomerular filtration. A high concentration of [3H]-paclitaxel was also noted in the choroid plexus [432 nM (167)], but [3H]-paclitaxel was not detected in the brain parenchyma, spinal cord, dorsal root ganglion, peripheral nerve, or the testicles. The pathogenesis of paclitaxelinduced neurotoxicity remains obscure given its limited distribution in the nervous system. In addition, these results suggest that systemically administered paclitaxel is not likely to be effective for the treatment of malignancies in the testes or the nervous system. 相似文献