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101.
JF Tsai HS Margolis JE Jeng MS Ho WY Chang MY Hsieh ZY Lin JH Tsai 《Canadian Metallurgical Quarterly》1998,86(3):246-251
24 consecutive AIDS patients with wasting, and who had never received anabolic therapies, were evaluated to determine their profile of sex hormones and whether transformation of testosterone (T) to the nuclear androgen, dihydrotestosterone (DHT), was impaired. Eleven (46%) patients had normal testosterone and DHT (group I), 10 (42%) had normal testosterone but low DHT (group II), and 3 (12%) had low testosterone and low DHT (group III). Age, prior opportunistic complications, symptoms, serum albumin, hemoglobin levels, and CD4 lymphocyte counts were similar in the groups. DHT was significantly lower (22.2 +/- 6.8 microg/dl) in group II compared with group I (50.8 +/- 15.3 microg/dl). The ratio of T/DHT, a measure of the conversion of testosterone to DHT, in group I was 15.1 +/- 3.5, which was within the range for eugonadal young men. In group II, the ratio was 22.3 +/- 1.5, indicating a defect in generation of DHT. Patients in group II had lost 9.2 +/- 3.5 kg compared with 5.6 +/- 2.6 kg in group I (p = .015). Thus, a syndrome of low DHT with normal testosterone was associated with significantly greater weight loss than in patients with normal testosterone and DHT. Further studies are needed to clarify whether low DHT is a result of AIDS wasting or is causally related to weight loss and whether androgen therapy in the form of DHT could reverse some of the metabolic changes associated with AIDS wasting. 相似文献
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105.
M el-Shourbagy KM Diab MY Abdalla MA el-Salam SH Mohasb 《Canadian Metallurgical Quarterly》1998,24(1):21-25
OBJECTIVE: This study was conducted to evaluate the psychological distress in patients with tinnitus that is often correlated with sleeping disorders, difficulties in concentration, and compromized social relations. METHODS: Eighty-four patients were studied using preliminary clinical and audiologic evaluations, and successive psychological tests. RESULTS: The cluster analysis indicated two essential groups composed of 45 patients (CLST-1) and 38 patients (CLST-2), respectively. The CLST-1 group had higher scores for depression, anxiety, and neuroticism. The IBQ CLST-1 revealed a greater degree hypochondria, conviction of disease dysphoria, and irritability. CONCLUSIONS: Our results indicate that the relationship between the intensity of the tinnitus and the extent of the distress is supported by the larger number of patients with more intense tinnitus in the first cluster. The CLST-2 with its normal psychological test results, apart from marked denial, would support the hypothesis of a somatic expression of the distress. 相似文献
106.
L Alvarez MY Rios C Esquivel MI Chávez G Delgado MI Aguilar ML Villarreal V Navarro 《Canadian Metallurgical Quarterly》1998,61(6):767-770
Two new cytotoxic isoflavans, (3S)-7-hydroxy-2',3',4',5', 8-pentamethoxyisoflavan (1) and (3S)-3',7-dihydroxy-2',4',5', 8-tetramethoxyisoflavan (2), were isolated from the bark and trunks of Eysenhardtia polystachya (Leguminosae), together with the known constituents stigmasterol, isoduartin, cuneatin, 7-hydroxy-2',4', 5'-trimethoxyisoflavone, and 3,4-dimethoxy-8, 9-(methylenedioxy)pterocarpan. The structures of 1 and 2 were elucidated on the basis of spectroscopic methods. The antimicrobial, cytotoxic, and insecticidal potential of some of these compounds were evaluated. The isoflavans 1, 2, and isoduartin (2', 7-dihydroxy-3',4',8-trimethoxyisoflavan) displayed moderate cytotoxic activity against KB cell lines. 相似文献
107.
D Mruk CH Cheng YH Cheng MY Mo J Grima B Silvestrini WM Lee CY Cheng 《Canadian Metallurgical Quarterly》1998,59(2):298-308
Rehabilitative measures for stroke are not generally based on basic neurobiological principles, despite evidence from animal models that certain anatomical and pharmacological changes correlate with recovery. In this report, we use functional magnetic resonance imaging (fMRI) to study in vivo human brain reorganization in a right handed patient with an acquired reading disorder from stroke. With phonological dyslexia, her whole-word (lexical) reading approach included inability to read nonwords and poor reading of function words. Following therapy, she was able to read nonwords and function words, and preferred a decompositional (sub-lexical) strategy in general. fMRI was performed during a reading task before and after treatment. Prior to therapy, her main focus of brain activation was in the left angular gyrus (area 39). After therapy, it was instead in the left lingual gyrus (area 18). This result suggests first that it is possible to alter brain physiology with therapy for acquired language disorders, and second, that two reading strategies commonly used in normal reading use distinct neural circuits, possibly reconciling several conflicting neuroimaging studies of reading. 相似文献
108.
Flaviviruses are small, enveloped RNA viruses which are generally transmitted by arthropods to animals and man. Although flaviviruses cause important diseases in domestic animals and man, flaviviral infection of animals which constitute the normal vertebrate reservoir may be mild or sub-clinical, which suggests that some adaptation between virus and host may have occurred. While this possibility is difficult to study in wild animals, extensive studies using laboratory mice have demonstrated the existence of innate, flavivirus-specific resistance. Resistance is heritable and is attributable to the gene Flvr, which is located on chromosome 5 in this species. The mechanism of resistance is at present unknown, but acts early and limits the replication of flaviviruses in cells. While some evidence supports a role for Flvr in enhancing the production of defective interfering virus, thereby restricting the production of infectious virus, other reports suggest that Flvr interferes with either virus RNA replication or RNA packaging. Recent research suggests that cytoplasmic proteins bind to the viral replication complex and that allelic forms of these proteins in resistant mice may restrict the production of infectious progeny. Apparent resistance to flaviviruses has been described in other vertebrates, although it remains to be seen if this is attributable to a homologue of Flvr. Nonetheless, knowledge gained of the characteristics and function of Flvr in mice should be applicable to other host species, and improvement of resistance to flaviviral infection in domestic animals by selective breeding or gene technology may ultimately be possible. 相似文献
109.
This study examined the cardiovascular correlates of posttraumatic stress disorder (PTSD) in Vietnam combat veterans using 24-hr ambulatory blood pressure and heart rate monitoring. Veterans with PTSD (n = 11) exhibited significantly higher heart rate and diastolic blood pressure across the 24 hr than veterans without PTSD (n = 7) (80.8 vs. 71.9 bpm, and 80.1 vs. 71.5 mm Hg, respectively). Heart rate during sleep was also significantly higher among veterans with PTSD, compared to veterans without PTSD (71.0 vs. 62.7 bpm). These results, based on a more naturalistic measurement methodology used outside the laboratory, support an association between PTSD and increased chronic cardiovascular arousal. 相似文献
110.
JM Bae MY Ahn CH Harn WJ Jeong M Jung YP Lim JR Liu 《Canadian Metallurgical Quarterly》1998,8(4):466-470
STUDY OBJECTIVE: To determine whether an intensive educational campaign of emergency department personnel on the organ donor and procurement process would result in both increased organ donor referrals and organs procured. METHODS: A retrospective review of the performance of an urban teaching ED in identifying and referring potential organ donor candidates was performed. Subsequently an intensive educational campaign of all ED staff, in conjunction with the Regional Organ Procurement Agency of Southern California (ROPA), was initiated. Physicians and nurses were educated about the procurement process, and a ROPA representative was on call 24 hours a day to assist in this process. The need for aggressive resuscitation and vital sign maintenance in potential donors as a strategy to promote organ recovery was emphasized. Reeducation by ROPA occurred every 2 to 3 months. The identification and referral rates were then retrospectively reviewed to evaluate any improvement. RESULTS: In 1994 the initial referral rate of potential organ donors from the ED was 30% (3 of 10) resulting in no organs procured. After the intervention the referral rate increased to 100% (25 of 25) in 1995 (P < .0001). The number of actual donors procured was 0 in 1994, 5 in 1995, and 9 in 1996. The increased ED referrals resulted in 14 and 32 organs procured in 1995 and 1996, respectively. CONCLUSION: Emergency physicians are in a unique position as first caregivers to interact with both potential donors and their families. With intensive education of ED staff, proper identification and referral, as well as timely intervention by organ procurement representatives, the consent and donation rate of organs for transplantation can be increased and maintained. 相似文献