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991.
992.
Preparations containing collagen play a prominent role among local haemostyptic agents in surgery. Sheets of collagen are used as degradable haemostyptic tampons. Various investigations have shown better haemostasis with collagen compared to other degradable materials, although the haemostyptic effect of these collagen preparations is limited. Concerning the mechanism of haemostasis, not all the reactions stimulated, e.g. by the collagen of an injured vessel wall, may be activated by a haemostyptic tampon from collagen. This depends very much on the kind of preparation. The combined application of a sheet of collagen with fibrin glue improved local haemostasis to a great extent. Large areas of capillary bleeding can be treated successfully with this method. Despite the very good results, this method has not been applied on a broad scale. This is due to the necessary skill and experience and the relatively cumbersome preparation required at the operation site. These drawbacks have been overcome with the latest development in this field--a sheet of collagen covered with a fixed layer of the solid components of a fibrin glue (fibrinogen, thrombin and aprotinin). The performance of this new local haemostyptic agent is described with special emphasis on the results of clinical trials. Haemostasis of large areas of capillary bleeding was very efficient and safe with the new material. Moreover, bile leakage and liquor, pancreatic and aerial fistulae could be sealed without problems. 相似文献
993.
U Ikeda F Ohkawa Y Seino K Yamamoto Y Hidaka T Kasahara T Kawai K Shimada 《Journal of molecular and cellular cardiology》1992,24(6):579-584
We have examined serum interleukin 6 (IL-6) levels in 12 patients with acute myocardial infarction (AMI). IL-6 levels became elevated in all patients, following the rise of serum creatine kinase (CK) activity. Peak IL-6 levels showed a good correlation with peak serum C-reactive protein (CRP) levels, while there was no direct relationship between peak IL-6 levels and peak CK activity. IL-6 mRNA was not detected in unstimulated "quiescent" rat cardiocytes cultured in serum-free medium, but its expression was induced by exposure of the cells to serum or ionomycin. These results show that IL-6 is synthesized in the myocardium and serum IL-6 levels become elevated in AMI, suggesting that IL-6 could affect the progression and/or healing processes of AMI. 相似文献
994.
U Eibach 《Zeitschrift für Gerontologie》1992,25(1):3-9
Concurrent with a nursing shortage and the increasing indigent requiring care in Germany preliminary discussions are emerging about quality of life and the rights of this socioeconomic group. This contribution shows which effects such a discussion may have on the care of a most defenseless segment of our society. It counters those who deny these rights and opposes their view of human dignity, which is characterized by categories of self-consciousness and intellectual ability. According to the christian view, dignity is a transcendental state and cannot be categorized as an empirical matter by virtue of its presence or absence. Exaggerated ideals of health have overshadowed realities of incurable disease, lingering illness, and dying, and is easily leading us to discount such people as being "unworthy to live". According to the view presented nursing carers are valued. 相似文献
995.
Coto V Oliviero U Sorrentino P Cocozza M Ciarimboli M Lingetti M 《Archives of gerontology and geriatrics》1992,15(3):215-223
Idebenone (45 mg twice daily) was administered to 7 patients with moderate renal impairment (creatinine clearance 21-40 ml/min) for 10 days. Standard pharmacokinetic parameters were computed on day 1 (single administration) and on day 10. On day 1 the mean of the maximum plasma concentration values (C(max)) was 364 ng/ml (standard deviation (S.D.) 100); time to C(max) (t(max)) was in the range of 1-2 h for 6 patients and 12 h for the remaining patient: the mean was 3 h (S.D. 3.99); the mean area under the plasma concentration vs. time curve (AUC) was 3005 ng h/ml (S.D. 1152). On day 10 the mean C(max) was 531 ng/ml (S.D. 355.3), the mean t(max) was 0.07 h (S.D. 0.19), the mean AUC was 3167 ng/ml (S.D. 2944) and the mean elimination half-life (t(1/2)) was 4.9 h (S.D. 1.1). Idebenone metabolites (QS-4, QS-6 and QS-10) showed a kinetic profile similar to the parent compound, with pharmacokinetic parameters comparable to idebenone for QS-4 and lower than idebenone for QS-6 and QS-10. Idebenone was metabolized and easily excreted and no accumulation was observed for the compound and its metabolites. No significant modification of the biohumoral indexes and vital signs and no adverse reactions were observed. 相似文献
996.
997.
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
998.
GABA-induced inactivation of functionally characterized sites in cat visual cortex (area 18): effects on orientation tuning. 总被引:6,自引:0,他引:6
Microiontophoresis of the inhibitory transmitter GABA was used to reversibly inactivate small sites of defined orientation specificity at a horizontal distance of some 600 microns from single cells recorded in area 18 of cat visual cortex, and the effects on orientation tuning were studied. The receptive fields of cells at the recording and inactivation sites overlapped extensively. During the inactivation of sites where the orientation preference differed by 45 degrees or more from that of a recorded cell ("cross-orientation" sites), 65% of 54 cells tested showed significant broadening of orientation tuning, with a mean increase in tuning width (measured at half the maximum response) of 93%, and an almost fourfold increase in the relative response to the orientation orthogonal to the optimum, compared with the response to the optimum; four cells essentially lost their orientation tuning. Broadening of tuning reflected an increase in response to nonoptimal orientations and was reversible upon termination of GABA application. The effects on orientation tuning typically peaked within 10-15 min of the onset of GABA iontophoresis with 50-100 nA ejecting currents, and could not be replicated by inactivating sites where the orientation preference was similar to that of a recorded cell; when the orientation preference at the inactivation sites was within 22.5 degrees of that of a recorded cell ("iso-orientation" sites), only 3 of 22 cells showed significant broadening of tuning, and in these cases, the effects were relatively weak (mean increase in tuning width of 39% and a negligible change in the relative response to the orientation orthogonal to the optimum). The effect of inactivating "iso-orientation" sites consisted primarily in an increase in response magnitude. The difference in the magnitude of the effects on orientation tuning elicited by inactivating "cross-orientation" and "iso-orientation" sites was highly statistically significant. Additionally, inactivation of "cross-orientation" or "iso-orientation" sites elicited differential effects on orientation tuning in 10 of the 13 cells in which direct comparisons were made. It is argued that the observed broadening of tuning was due to the loss of a "cross-orientation" inhibitory input, which normally sharpens orientation tuning by suppressing responses to nonoptimal orientations. 相似文献
999.
Anticytoplasmic autoantibodies in the diagnosis and follow-up of Wegener's granulomatosis 总被引:9,自引:0,他引:9
U Specks C L Wheatley T J McDonald M S Rohrbach R A DeRemee 《Mayo Clinic proceedings. Mayo Clinic》1989,64(1):28-36
Sixty-five patients with biopsy-proven Wegener's granulomatosis (WG), 54 with systemic vasculitis, 22 with relapsing polychondritis, 20 with sarcoidosis, 20 with malignant pulmonary lesions, and 15 with other conditions underwent determination of anticytoplasmic autoantibodies (ACPA) by the indirect immunofluorescence technique on neutrophil cytospin preparations to assess the specificity of ACPA for WG, their sensitivity in relationship to the extent and activity of the disease, and their value for follow-up of WG. Of these 65 patients with WG, 38 were ACPA positive. Two patients in the vasculitis group, best categorized as having microscopic polyarteritis, were ACPA positive. We obtained 125 serum samples from the 65 patients with WG and assigned them to one of two categories (limited or generalized), based on the extent of disease. Each of these categories was then subdivided into "active" or "in remission." Median ACPA titers were significantly different between active disease and remission in each category, as well as between active limited and active generalized disease. All patients whose disease changed from active to in remission had reductions in ACPA titer levels; those who experienced flares had titer increases. Patients with intercurrent illnesses or complications of treatment, mimicking WG flares, did not have titer increases. We conclude that ACPA determined by the indirect immunofluorescence technique is highly specific for WG. The sensitivity is dependent on the extent and activity of WG, and serial titer determinations are valuable in monitoring disease activity. 相似文献
1000.
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