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61.
GW Gao SH Lin YF Lin LK Diang KC Lu FC Yu SD Shieh 《Canadian Metallurgical Quarterly》1996,57(6):438-442
Despite a general national decline in criminal activities in the 1990s, juvenile criminal offenses continue to increase, (including violent, property, and delinquency acts). In addition increased numbers of children are being held in juvenile jails. It is all but impossible for pediatric health providers to think that "their patients" and "their practices" are immune from the epidemic of crime that affects and is caused by "just kids." 相似文献
62.
Five male and four female normal weight research volunteers, participating in 13-day residential studies, received oral fenfluramine (20, 40 mg) or placebo at 09:30 and 17:00. Food intake, performance, and subjective ratings were measured throughout the day. Carbohydrate intake was manipulated by providing lunch meals high (males: 120 g; females: 80 g) or low (males: 25 g; females: 16 g) in carbohydrate on 8 days; on the remaining days subjects self-selected lunch. Total caloric intake (approximately 2800 Kcal) did not differ among the low- and high-carbohydrate, and self-selected lunch conditions when subjects received placebo, indicating caloric compensation. Total carbohydrate intake was significantly less, however, when subjects consumed the low-carbohydrate lunch compared to the other lunch conditions. Fenfluramine significantly decreased total caloric intake (approximately 500 kcal) by decreasing meal size, not number, only when subjects consumed the low-carbohydrate lunch. Fenfluramine was only an effective anorectic drug when subjects consumed a lunch with fewer calories and a lower carbohydrate:protein ratio than self-selected baseline. Also, fenfluramine improved performance on a range of computer tasks and increased ratings of "Alert," "Friendly," and "Talkative," while decreasing ratings of "Tired" and "Irritable." 相似文献
63.
CI Henschke DF Yankelevitz A Wand SD Davis M Shiau 《Canadian Metallurgical Quarterly》1996,34(1):21-31
264 patients with cancer of larynx, 21 female and 234 male, had a testosterone and sex hormone binding globulin (SHBG) before the treatment in serum estimated. Because of dependence of levels of hormones the group of patients was divided into three following groups: "lower than standard", "standard", "higher than standard". The correlation between these groups and sex, age, localization of tumor, organs' advances, stage of morphological malignancy and type of cancer was reported. Anomalous values of testosterone were in male group more frequently reported. Anomalous values of SHBG were similar in male and female groups, but in the female group there was a significant majority of "lower than standard" values reported. The majority of abnormal values of testosterone and SHBG was described in groups of age higher than 50 years. There were no differences in testosterone and SHBG levels in different localization of tumors in larynx. In advanced stage T3 and T4 there were more frequent lower mean values of testosterone levels and higher values of SHBG levels in comparison to T2 stages. In tumors in G1 and G2 stages of histological malignancy higher levels of SHBG and higher mean levels of testosterone. The tumors in stage G3 the hormone levels were lowers were observed. The levels of SHBG in groups of carcinoma planoepitheliale keratodes were in 66% higher than in a group of carcinoma planoepitheliale akeratodes but in both groups the levels of testosterone were nearing the same. In group of patients with larynx cancer the negative correlation between the levels of testosterone and SHBG was not observed. Higher SHBG levels were not always accompanied by lower testosterone levels. 相似文献
64.
SD Boden PA Moskovitz MA Morone Y Toribitake 《Canadian Metallurgical Quarterly》1996,21(22):2689-2697
STUDY DESIGN: Cadaveric anatomic and in vivo survival animal studies were performed to develop a new arthrodesis technique for the lumbar spine. OBJECTIVES: To examine the feasibility, efficacy, and safety of a minimally invasive lumbar intertransverse process arthrodesis technique using an osteoinductive growth factor (rhBMP-2) delivered in a collagen sponge carrier. The technique was first developed using a rabbit model and modified for the nonhuman primate (rhesus monkey), a larger animal with the most similar bone biology to humans. SUMMARY OF BACKGROUND DATA: The morbidity of conventional posterolateral lumbar intertransverse process arthrodesis includes graft donor site morbidity; paraspinal muscle devascularization, denervation, and scarring and nonunion in up to 36% of patients. Minimally invasive anterior lumbar interbody arthrodesis techniques have been developed, but these often require a metal implant and carry risks to major vessels and development of retrograde ejaculation. A minimally invasive technique for posterolateral intertransverse process arthrodesis has not been described previously. METHODS: In Part 1, we examined seven New Zealand white rabbits and five rhesus monkeys at necropsy and during nonsurvival surgeries to determine the best access routes and to develop special instruments for video-assisted lateral intertransverse process arthrodesis. In Part 2, 38 New Zealand white rabbits underwent L4-L5 intertransverse process arthrodesis: the "OPEN" group (n = 16) underwent a standard open muscle-splitting approach using rhBMP-2 (bone morphogenetic protein) and collagen as a bone graft substitute; the "video-assisted control" group (n = 6) underwent video-assisted lateral intertransverse process arthrodesis with the collagen implant only (no growth factor); and the "video-assisted-BMP" group (n = 16) underwent video-assisted lateral intertransverse process arthrodesis with rhBMP-2 and collagen as the graft material. In Part 3, rhesus monkeys (n = 4) underwent video-assisted lateral intertransverse process arthrodesis using rhBMP-2 and collagen after laminectomy of L4-L5. RESULTS: In Part 1, we identified expedient, minimally invasive routes to the intertransverse process interval appropriate for each species: an intermuscular approach for the rabbit and a lateral, extramuscular approach for the rhesus monkey. In Part 2, all rabbits in the OPEN and video-assisted-BMP groups achieved solid intertransverse process lumbar fusions when assessed at 10 weeks. There were no neurologic impairments nor any difference between the two groups in the frequency of postoperative infection or other complications. None of the animals in the video-assisted control group showed evidence of fusion. In Part 3, exposure, decortication and grafting with rh-BMP-2 and collagen was accomplished successfully in all four monkeys through the video-assisted minimally invasive approach without complications. CONCLUSION: Video-assisted lateral intertransverse process arthrodesis is a feasible, effective, and safe method of lumbar spinal fusion in the rabbit and rhesus monkey. Use of this arthrodesis procedure will minimize the morbidity of paraspinal muscle denervation and devascularization seen with open intertransverse process fusion techniques, and the use of an osteoinductive growth factor will eliminate the problem of graft donor site morbidity and possibly increase the chances for successful fusion. 相似文献
65.
An intrinsic formulation of geometric proportional–derivative tracking control for fully actuated mechanical systems is developed. The region of stability is determined directly from the size of the system’s injectivity radius and, for a restricted set of control problems, the system’s locus of cut points about a desired reference point. Exponential stability is obtained under certain boundedness conditions. For controlled motion along a geodesic, the proffered scheme yields a particularly simple and elegant manifestation of the underlying use of the mass–spring–damper paradigm in the control design methodology. 相似文献
66.
For successful parasitization, the female Campoletis sonorensis endoparasitic wasp injects a polydnavirus into its host, Heliothis virescens, during oviposition. Viral gene expression induces immunosuppression and alters development of the host. We report here that three abundantly expressed genes, VHv1.1, WHv1.0, and WHv1.6, describes a polydnavirus "cysteine-rich" gene family which may be important in inducing these host manifestations. These genes have a similar primary gene structure and their proteins contain cysteine motifs characteristic of snail ion-channel ligands, the omega-conotoxins. Like the omega-conotoxins, the intercysteine amino acid residues are hypervariable with only three identical amino acids in all motifs. The conservation of this domain in the three viral genes may reflect an important functional role for these viral proteins in the parasitization of H. virescens. The three genes also contain introns similar in sequence at comparable positions in their 5' untranslated leaders and coding sequences. VHv1.1 contains two cysteine motifs, and each motif is interrupted by an intron at the same position as in the cysteine motifs of WHv1.0 and WHv1.6. Intron 2 sequences of WHv1.0 and WHv1.6 are 92% identical, while the immediately flanking exon sequences encoding the cysteine motifs are only 76% identical. This provides an example of nuclear pre-mRNA introns which are more conserved than flanking exons among members of a gene family. 相似文献
67.
Hicks Thomas V.; Leitenberg Harold; Barlow David H.; Gorman Jack M.; Shear M. Katherine; Woods Scott W. 《Canadian Metallurgical Quarterly》2005,73(3):506
The authors explored the prognostic value of 3 different types of catastrophic cognitions in the treatment of panic disorder with and without mild-to-moderate agoraphobia using a sample of 143 participants who received either cognitive-behavioral therapy (CBT) or imipramine in a randomized controlled trial. Stronger fears of social catastrophes both prior to and following treatment with CBT or imipramine were associated with a poorer outcome. In contrast, cognitions involving physical or mental catastrophes were unrelated to outcome, regardless of whether these thoughts were measured prior to or following treatment. These findings are consistent with the notion that although the intensity of physical catastrophe cognitions may best discriminate between panic disorder and other anxiety disorders, it is the intensity of social catastrophe cognitions that is most closely tied to success in treating this disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
68.
MacDonald Angus W. III; Goghari Vina M.; Hicks Brian M.; Flory Janine D.; Carter Cameron S.; Manuck Stephen B. 《Canadian Metallurgical Quarterly》2005,19(6):814
Convergent and divergent validity are critically important in developing psychological measures that reveal interpretable deficits in disordered populations. This article reports on 2 studies that evaluated the validity of context processing measures. In Experiment 1, a confirmatory factor analysis of data from 481 healthy adults established the convergent validity of 2 context processing measures and showed that context processing accounted for significant amounts of variance in standard IQ and working memory measures. In Experiment 2, 20 schizophrenia patients, 16 of their healthy siblings, and 28 controls were evaluated using a novel, short context processing measure, the dot pattern expectancy (DPX) task. The DPX was sensitive to specific deficits in schizophrenia patients and their healthy siblings. These findings support the construct validity of context processing measures, suggest context processing is a component of intellectual functioning, and demonstrate that brief context processing measures remain sensitive to psychopathological deficits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Krueger Robert F.; Nichol Penny E.; Hicks Brian M.; Markon Kristian E.; Patrick Christopher J.; lacono William G.; McGue Matt 《Canadian Metallurgical Quarterly》2004,16(2):107
Recent research points toward the viability of conceptualizing alcohol problems as arrayed along a continuum. Nevertheless, modern statistical techniques designed to scale multiple problems along a continuum (latent trait modeling; LTM) have rarely been applied to alcohol problems. This study applies LTM methods to data on 110 problems reported during in-person interviews of 1,348 middle-aged men (mean age=43) from the general population. The results revealed a continuum of severity linking the 110 problems, ranging from heavy and abusive drinking, through tolerance and withdrawal, to serious complications of alcoholism. These results indicate that alcohol problems can be arrayed along a dimension of severity and emphasize the relevance of LTM to informing the conceptualization and assessment of alcohol problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Hicks Brian M.; Markon Kristian E.; Patrick Christopher J.; Krueger Robert F.; Newman Joseph P. 《Canadian Metallurgical Quarterly》2004,16(3):276
The authors used model-based cluster analysis to identify subtypes of criminal psychopaths on the basis of differences in personality structure. Participants included 96 male prisoners diagnosed as psychopathic, using the Psychopathy Checklist Revised (PCL-R; R. D. Hare, 1991). Personality was assessed using the brief form of the Multidimensional Personality Questionnaire (MPQ-BF; C. J. Patrick, J. J. Curtin, & A. Tellegen, 2002). The best-fitting model yielded two clusters. Emotionally stable psychopaths were characterized by low Stress Reaction and high Agency. Aggressive psychopaths were characterized by high Negative Emotionality, low Constraint, and low Communion. These results suggest that psychopaths as defined by the PCL-R includes distinct subtypes, distinguishable in terms of personality structure, that may reflect different etiologies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献