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11.
The bioavailability of two oral formulations of trimipramine, tablets and solution, was performed in twelve healthy volunteers, in a cross-over study. Each formulation was administered in the morning after a fasted period, and in the evening after a meal, in order to evaluate the role of both administration time and food consumption on the plasma kinetic parameters, under usual therapeutic conditions. A high interindividual variability of data was found. First, the extent of bioavailability was identical for the two formulations but the rate of bioavailability seemed to be different, with the p.o. solution, being more rapidly absorbed (tmax = 1.50 h). The effect of administration time was more obvious for the solution as shown by a lower quantitative absorption as well as a delay in time to reach the maximal concentration. Regardless of formulation and administration time, the t1/2 beta was about 10 hours and the mean MRT value was 11 hours.  相似文献   
12.
The activity of stereoisomeric [1,2-bis(3-hydroxyphenyl)ethylenediamine] dichloroplatinum(II)-complexes (1-PtCl2,R,S; 2-PtCl2, R,R/S,S; 3-PtCl2, R,R; 4-PtCl2, S,S) on several tumor models (MDA-MB 231 breast cancer cell line; P 388 leukemia, mouse; L 1210 leukemia, mouse; L 5222 leukemia, rat; Ehrlich ascites tumor, mouse--wildtype; cisplatin-, etoposide-, cyclophosphamide-, and daunomycin-resistant, resp.) is described. For comparison the analogous [1,2-bis(4-hydroxyphenyl)ethylendiamine]dichloroplatinum (II)-complexes (5-PtCl2, R, S; 6-PtCl2, R,R/S,S; 7-PtCl2, R,R; 8-PtCl2, S,S) and cisplatin are used. 1-PtCl2 to 4-PtCl2 (OH in 3,3'-positions) show their maximum antitumor effect at lower doses than 5-PtCl2 to 8-PtCl2 (OH in 4,4'-positions). 2-PtCl2 and 6-PtCl2 (R,R/S,S) are more active than 1-PtCl2 and 5-PtCl2 (R,S). 4-PtCl2 and 8-PtCl2 (S,S) are superior to 3-PtCl2 and 7-PtCl2 (R,R). On the L 5222 leukemia 2-PtCl2 (R,R/S,S), 4-PtCl2 (S,S) and 8-PtCl2 (S,S) markedly surpass cisplatin. Strong effects are produced by 2-PtCl2 to 4-PtCl2 on the Ehrlich ascites tumor (wildtype, cisplatin-, etoposide-, cyclophosphamide-, and daunomycin-resistant, resp.). The combination of 4-PtCl2 with cisplatin results in a weakly synergistic effect.  相似文献   
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The relationship of current use of cigarettes, marijuana and alcohol to the parameters of seminal fluid analysis, sperm penetration assay and sperm autoimmunity was studied in 164 men from infertile couples. Current cigarette smokers, marijuana users and heavy alcohol users showed greater numbers of leukocytes in the seminal fluid than did nonusers (p less than 0.02, less than 0.007 and less than 0.01, respectively). In addition, cigarette smokers had lower sperm penetration assay scores than nonsmokers (median 2.5 versus 8.0, p = 0.05). Users of cigarettes, marijuana or alcohol showed no decrease in sperm count, motility or percentage of oval sperm, and no difference in prevalence of antisperm antibodies compared to nonusers. After controlling for past sexually transmitted diseases and multiple substance exposures in a multivariate model, use of cigarettes (p = 0.006), marijuana (p = 0.12) or alcohol (p = 0.098) continued to be associated with a trend toward increased number of seminal fluid leukocytes. Cigarette smoking continued to show a significant decrease in sperm penetration assay score (p = 0.03).  相似文献   
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16.
Although it is chemically a classical tricyclic antidepressant agent, trimipramine shows atypical pharmacological properties. Its well-documented antidepressant action cannot be explained by noradrenaline or serotonin reuptake inhibition or by a down-regulation of β-adrenoceptors. Furthermore, its receptor affinity profile resembles more that of clozapine, a neuroleptic drug, than that of tricyclic antidepressants. Trimipramine does not reduce, but rather increases, rapid eye movement sleep. It stimulates nocturnal prolactin secretion and inhibits nocturnal cortisol secretion, and may act at the level of the hypothalamus on corticotropin-releasing hormone secretion. Trimipramine is of particular value in depressed patients with insomnia, and it has been shown to be effective in the therapy of primary insomnia. As the pharmacological profile indicates, and an open clinical study has shown, trimipramine might also be active as an antipsychotic. The drug is both a tool for increasing our understanding of depression and a potential therapy for several psychiatric disorders.  相似文献   
17.
As a result of modern therapeutic and technological advances, the surgeon has the ability to salvage even the most severely injured lower limbs. However, the success of replantation nowadays is no longer measured simply on the basis of restoration of viability but also on functional outcome compared with primary amputation with early prosthetic fitting, the risk to the patient during and after replantation and the overall time of treatment which should not exceed 2 years. Although every major limb replantation has to be considered individually, the decision-making process for reconstruction (replantation/revascularisation) versus amputation with subsequent early prosthetic fitting should be determined by objective criteria. Based on personal experience and an extensive literature search, an algorithm for treatment of amputation or amputation-like injuries to the lower leg has been developed and tested in a clinical study. A 100% viability success rate was achieved. There was not only a significant increase in the percentage of “functional extremities” but also a doubling in grade I results. Moreover, there was a 50% reduction in patients presenting a “non-functional extremity”, and no patient required a secondary re-amputation. The replantation risk (e.g., risk of severe systemic disturbance during and/or after replantation) was about 16.6% (2/12) in our study. There was a significant decrease in the postoperative complication rate and no patient died during or after replantation. Based on our experience, if reconstruction in subtotal or total lower leg amputation is done for a well-selected patient group, good functional results with a reasonable replantation risk and a reasonable time for social re-integration can be achieved. © 1995 Wiley-Liss, Inc.  相似文献   
18.
Mentosternal contractures still represent a surgical challenge due to their prominent position. They require early operative treatment for both function and aesthetic reasons. Careful clinical examination of scar position and traction forces, both at rest and when functioning, in addition to proper evaluation of the surrounding soft tissue are mandatory for precise preoperative planning of the required reconstruction. In general, the technically most feasible operation is favored if the functional and aesthetic results are good and postoperative risk for recurrence is low. Between 1987 and 1994, 21 patients with cervical, mentosternal, and mentothoracic contractures were operated upon. Eight patients were reconstructed with local flaps and 13 with microvascular free flaps.  相似文献   
19.
The study was performed to assess the ethiological role of bile in acute pancreatitis provoked by closed duodenal loop in rat. In group I a closed duodenal loop was created by method of Nevalainen. A similar operation was performed in group II, but the common pancreatico-biliary duct was ligated just under the liver. In the control group (group C) only the mobilization of duodenum was performed. After 24 hours the mortality rate was 20% in group I, but 0% in group II and C. The amount of ascitic fluid showed significant elevation in group I versus II and group C, and in group II as compared to group C, too. The serum amylase was significantly higher in group I than group II and group C, and in group II was also higher as compared to group C. Serum total protein differed significantly between all groups, while albumin and total calcium were significantly lower in group I than group II, but group II was only slightly reduced versus group C. Histology showed no differences between groups I and II, but both differed significantly from group C. In conclusion bile seems to be an aggressive factor in pathogenesis of acute pancreatitis induced by closed duodenal loop in rat, but other factors may play more important roles.  相似文献   
20.
On the surface of the free (receptor-unbound) form of hCG, we have previously identified 14 topographically distinct epitopes (Schwarz et al. (1986) Endocrinology 118, 189-197; Berger et al. (1990) J. Endocrinol. 125, 301-309). Here we report that only two of them, i.e. the (adjacent) beta 3 and beta 5 epitopes, can be recognized by 125iodine-labeled monoclonal antibodies when hCG was specifically bound to the rat testis hCG receptor. The exclusive accessibility of precisely these two surface epitopes indicates that hCG assumes a defined rather than a stochastic orientation in its receptor-bound state. The inaccessibility of 12 of 14 epitopes is consistent with the idea that the 341 residues long extracellular domain of the recently cloned hCG receptor (MacFarland et al. (1989) Science 245, 494-499) is the ligand binding domain. It is proposed that the extracellular domain is folded in a way that a cavity is formed large enough to accommodate hCG. Thereby, a considerable portion of the total surface of hCG is covered, as reflected by the masking of most of its epitopes.  相似文献   
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