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61.
In this study, we describe the activity of CT1746, an orally-active synthetic MMP inhibitor that has a greater specificity for gelatinase A, gelatinase B and stromelysin than for interstitial collagenase and matrilysin, in a nude mouse model that better mimics the clinical development of human colon cancer. The model is constructed by surgical orthotopic implantation (SOI) of histologically-intact tissue of the metastatic human colon tumor cell line Co-3. Animals were gavaged with CT1746 twice a day at 100 mg/kg for 5 days after the SOI of Co-3 for 43 days. In this model CT1746 significantly prolonged the median survival time of the tumor-bearing animals from 51 to 78 days. Significant efficacy of CT1746 was observed on primary tumor growth (32% reduction in mean tumor area at day 36), total spread and metastasis (6/20 treated animals had no detectable spread and metastasis at autopsy compared to 100% incidence of secondaries in control groups). Efficacy of CT1746 could also be seen on reducing tumor spread and metastasis to individual organ sites such as the abdominal wall, cecum and lymph nodes compared to vehicle and untreated controls. We conclude that chronic administration of a peptidomimetic MMP inhibitor via the oral route is feasible and results in inhibition of solid tumor growth, spread and metastasis with increase in survival in this model of human cancer, thus converting aggressive cancer to a more controlled indolent disease.  相似文献   
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Summary When the histamine (HA) turnover in the brain of mice was estimated on the basis of the pargyline-induced accumulation of tele-methylhistamine (t-MH), a predominant metabolite of brain HA, the enhancing effect of phencyclidine (PCP) on the HA turnover was antagonized by a large dose of naloxone. However, a dopamine receptor antagonist haloperidol, which is also a potent receptor antagonist, did not inhibit the effect of PCP on the HA turnover. [abetd-Ala2, abetd-Leu5]enkephalin, a prototypic opioid agonist, markedly enhanced the HA turnover. The effect of this peptide was demonstrated not only when the HA turnover was determined by the pargyline-induced t-MH accumulation but when it was estimated by the HA depletion induced by -fluoromethylhistidine, a specific inhibitor of histidine decarboxylase. A agonist, SKF-10047, and a agonist, ethylketazocine, had no PCP-like enhancing effect on the HA turnover. These results suggest that PCP enhances the brain HA turnover in mice by stimulating, probably indireclty, endogenous opioid systems. Send offprint requests to K. Saeki at the above address  相似文献   
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Although single-lung transplant on the side with better lung function is challenging in patients with significantly asymmetrical lung function between the right and left sides, it sometimes can be a realistic option because of the recipient's condition and from the viewpoint of organ sharing. We report our experience with a successful case of single-lung transplant on the side with a pulmonary perfusion ratio of 89%. The transplant was performed with the patient under central venoarterial extracorporeal membrane oxygenation through a clamshell incision, and the patient had an acceptable short- and long-term outcome with a remarkable improvement of lung function.  相似文献   
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A long-standing assumption in molecular biology posits that the conservation of protein and nucleic acid sequences emphasizes the functional significance of biomolecules. These conserved sequences fold into distinct secondary and tertiary structures, enable highly specific molecular interactions, and regulate complex yet organized molecular processes within living cells. However, recent evidence suggests that biomolecules can also function through primary sequence regions that lack conservation across species or gene families. These regions typically do not form rigid structures, and their inherent flexibility is critical for their functional roles. This review examines the emerging roles and molecular mechanisms of “nondomain biomolecules,” whose functions are not easily predicted due to the absence of conserved functional domains. We propose the hypothesis that both domain- and nondomain-type molecules work together to enable flexible and efficient molecular processes within the highly crowded intracellular environment.  相似文献   
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Conclusion  We are morally obligated to select therapies which are maximally beneficial for patients. Promoting or discouraging the use of a particular treatment modality, such as BCT, should never be a consideration. To meet this goal, our society must establish guidelines as a part of comprehensive policy. The specialist system, launched under the auspices of the specialist system committee, will hopefully lead to further development of the Japanese Breast Cancer Society.  相似文献   
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BACKGROUND: Current paradigms for conceptualizing alcohol-related problems typically focus on persons who are abusing or dependent on alcohol. These paradigms may not apply to older drinkers whose alcohol use, regardless of consumption-level, can cause problems because of age-related changes in physiology and interactions with increased morbidity, medication use, and functional limitations. OBJECTIVE: We convened an expert panel# to develop clinical indications of harmful, hazardous, and nonhazardous drinking in persons 65 years of age and older. RESEARCH DESIGN AND SUBJECTS: Nine panelists with expertise in psychiatry, geriatrics, internal medicine, and alcohol research were provided with epidemiological data and a published explicit literature review of alcohol use in the elderly. The RAND/UCLA two-round panel method was used to develop the indications. After the second round, the authors wrote a draft statement that was circulated to the panelists whose comments were incorporated into a final document. RESULTS: Panelists agreed on 215 scenarios in which older peoples' use of alcohol either alone or in the presence of chronic medical conditions, medication use, symptoms, smoking, and functional limitations are hazardous or harmful. Panelists' ratings of risk did not differ significantly between persons aged 65 to 74 years and those aged 75 years and older. CONCLUSION: Alcohol use may be hazardous or harmful for older persons, particularly in conjunction with physical or emotional illnesses, medication use, functional limitations, smoking, and driving after drinking. When asking about alcohol use in older persons, clinicians need to be aware of these factors to assist in identifying and managing potential or actual alcohol-related problems.  相似文献   
68.
Adult cats were spinal transected (T12-13) and maintained for approximately 6 months. Spinal cats were either not trained (N-T) or trained for 30 min/day to either step on a treadmill (Stp-T) or stand (Std-T). Spinalization resulted in a decrease in the mass and maximum tension potential of the medial gastrocnemius (MG), a fast ankle extensor. These adaptations were ameliorated in Std-T but not Stp-T cats. The maximum rate of shortening was elevated by 18 (ns), 34, and 19 (ns)% in the N-T, Std-T, and Stp-T cats, respectively, a finding consistent with a shift in the percentage of fast fibers, a decrease in the percentage of fibers expressing only type I myosin heavy chain, and an increase in myofibrillar adenosine triphosphatase activity. The shift toward a faster fiber type profile in the tibialis anterior (TA), a fast ankle flexor, was of a lesser magnitude than in the MG. There were no significant effects on the contractile properties of the TA in any group of spinal cats. The greater preservation of muscle mass, shift toward faster physiological and biochemical properties, and fatigability in the MG of Std-T than Stp-T cats suggest that factors other than the level of activation and force generation must play a role in muscle homeostasis. From a clinical perspective, the results indicate that muscles innervated by motor neurons below the level of a complete spinal cord lesion are affected differentially by specific neuromuscular activity patterns.  相似文献   
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