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An in vitro assay, which evaluates drug effect on 3H-thymidine incorporation, was used to investigate the absolute and relative activities of cisplatin (DDP), carboplatin (CBDCA) and iproplatin (CHIP) on 317 specimens from untreated tumors, including breast and ovarian cancers and malignant melanomas. Similar activities were generally observed for DDP and CHIP, whereas CBDCA exhibited a lower, although not significantly different cytotoxicity on breast and ovarian cancers. The relative activities of Platinum analogues were analyzed on 239 two-way drug sensitivity comparisons. The overall agreement rates ranged from 80.2 to 83.9% for the different comparisons. High coresistance, from 61.1 to 93.8%, was observed for all the comparisons, regardless of the tumor type. Cosensitivity rates were poor for breast and ovarian cancers, from 0 to 37.5%, whereas for melanomas an association in sensitivity was observed in 80% of the cases.  相似文献   
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We describe a preparative procedure for low-abundance proteins of the cytoskeleton-nuclear matrix fraction from frozen bovine brain. Strigent centrifugation and washing conditions in the preparation of the cytoskeleton-nuclear matrix fraction are avoided to minimize loss of nuclear material. A recently described horizontal isoelectric focusing column, which tolerates appreciable precipitation, is used. In concert with selection of urea concentration and temperature, this isoelectric focusing apparatus provides a new approach to the fractionation of this complex, relatively insoluble mixture of proteins and other components. In addition, a heated, sodium dodecyl sulfate-sizing column has been utilized in order to eliminate interactions between the desired low abundance proteins and more abundant contaminating proteins. Together these procedures purify a specific low-abundance protein sufficiently to be detected by Coomassie blue staining in two-dimensional gels. The methods are robust and can be applied to multiple, relatively large brain samples (150 g of crude grey matter per batch); thus they should facilitate partial peptide sequencing for brain proteins of this operational class.  相似文献   
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Background. A major concern in evaluating dynamic cardiomyoplasty has been whether the synchronous stimulation of latissimus dorsi muscle is essential for benefit or not. We studied 10 patients to determine the efficacy of the systolic augmentation generated by the synchronous electrical stimulation of the latissimus dorsi muscle.

Methods. Left ventricular ejection fraction, end-systolic and end-diastolic volume indexes, and stroke volume index obtained during resting, peak exercise, and recovery periods (“on” values) were compared with those obtained 1 week after cessation of electrical stimulus (“off” values). Double product and estimated total body oxygen consumption at peak exercise were also calculated and compared.

Results. Higher ejection fractions (0.36 ± 0.07 versus 0.33 ± 0.06 at rest, 0.40 ± 0.07 versus 0.33 ± 0.07 peak exercise, and 0.37 ± 0.06 versus 0.31 ± 0.06 at recovery) and lower end-systolic volume indexes with relatively constant end-diastolic volume indexes were observed with the cardiomyostimulator on. Further, exercise response was better with the cardiomyostimulator on. Double product indirectly reflected better myocardial oxygen supply/demand ratio when on at peak exercise (17 ± 2.2 mm Hg × beats/min × 10−3 for on versus 19 ± 2.6 mm Hg × beats/min × 10−3 for off). Estimated total body oxygen consumption was improved at peak exercise when the cardiomyostimulator was functional (12 ± 2.7 mL · kg−1 · min−1 versus 11 ± 2.6 mL · kg−1 · min−1).

Conclusions. Current data suggest a true systolic assist during synchronous contractions of the latissimus dorsi muscle. It is thought, therefore, that synchronous electrical stimulation is essential for maximum benefit and all the beneficial effect of cardiomyoplasty certainly cannot be attributed to simple wrapping itself.  相似文献   

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U T Egle  U Porsch 《Der Nervenarzt》1992,63(5):281-288
According to the results of the prospective Grant-Study the maturity of the individually available defence mechanisms has an essential influence on both physical and psychic well-being. Psychogenic pain patients are characterized by a "turning against self": an immature defense mechanism. By means of a cluster analysis, three taxonomic subgroups (types A, B, C) were defined. Type A is characterized by immature defense mechanisms (projection, turning against self and against object) and type C by neurotic defances (reaction formation and intellectualization), whereas type B manifests both intellectualization and a turning against self. Raised scores for anxiety, abnormal illness behaviour, depressive self-image, depressive mood and suicidal ideas are additional features which distinguish types A and B from type C. In contrast to type B, type A shows a negative social resonance, "doctor shopping" and drug abuse. The diagnostic differentiation of types A, B and C could be the basis of a differential indication to the different psychotherapeutic treatment approaches to chronic pain patients.  相似文献   
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The gate control theory resulted in intensified consideration and investigation of psychological factors in the pathogenesis and continuation of chronic pain. This had led to an increasing interest in the efficacy of psychotherapy for such patients. The different forms of psychotherapy (hypnosis, relaxation, behavior therapy, psychodynamically oriented therapy) currently most often applied are reviewed with notes on the methods and the efficacy recorded for each. The psychodynamically oriented approach has most often been omitted from previous reviews but is integrated in this paper. Four psychodynamic mechanisms are differentiated: the narcissistic mechanism ("psychoprothetic function" of pain), the conversion mechanism ("symbolic function" of pain), the psychovegetative tension mechanism (pain as equivalent of emotion) and the learning mechanism (secondary gain from pain). Generally speaking, a good level of efficacy was ascertained for each form of psychotherapy considered. Hypnosis and relaxation can reduce depression and the perception of pain. Operant programs reduce medication intake and increase the level of activity. Cognitive behavioral strategies are aimed at changing the pain patient's fixation on the body. Psychodynamic approaches concentrate on biographical factors and communication with significant others before the onset of pain reflected in the therapist-patient relationship. However, the value of the results is restricted by the lack of information on patient selection in nearly all the studies considered. The small numbers of patients evaluated in most of the studies suggest that the population investigated may well not be representative, especially if the difficulty of motivating chronic pain patients to present for psychotherapy is taken into account. In addition, a diagnostic classification of the population investigated is lacking. Conclusions are drawn for the planning of future therapy studies.  相似文献   
8.
The author emphasizes that conservative rhinoplasty techniques are frequently satisfactory, but in certain techniques there is a limit to which nasal tips can be reshaped. In certain circumstances, therefore, interruption of the domes of the alar cartilages is suggested to achieve the most satisfactory aesthetic results.  相似文献   
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Clinical Rheumatology - This paper evaluates the prevalence and severity of periodontitis (PD) in patients with rheumatoid arthritis (RA), focusing on the link between the severity of PD with RA...  相似文献   
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