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51.
Geoffrey M. Collins B. Sc. M.B.M.S. F.R.C.S. Peter Taft M.D. Richard D. Green B.S. Roswitha Ruprecht Nicholas A. Halasz M.D. 《World journal of surgery》1977,1(2):237-242
This study explored the relationship between adenine nucleotide levels in canine renal cortex and renal function following: (a) graded periods of warm ischemia; (b) 48 hours' flush cooling with electrolyte solutions and ice storage; and (c) continuous hypothermic perfusion. Exposure to normothermic ischemia resulted in a rapid (within 15 minutes) degradation of ATP to ADP and AMP as well as a slow decline in total adenine nucleotide (TAN) to levels which were proportional to the duration of the ischemic injury. No functional impairment was evident after 15 minutes' ischemia, but with longer times, both the extent of decline in TAN and the degree of recovery following restoration of blood flow could be used to predict the quality of renal function.The relationship between TAN levels and function was of less predictive value following cold storage or continuous perfusion. The efficacy of intracellular flush solutions could not be attributed solely to conservation of TAN, nor did the well-maintained TAN levels during continuous perfusion necessarily lead to significantly better 48-hour storage than flush cooling with C2 solution.
Supported by Veterans Administration Research Grant 1519-01. 相似文献
Résumé Cette étude faite chez le chien examine la corrélation entre la fonction rénale et le taux d'adénine nucléotide dans le cortex rénal suite à: 1) différentes périodes d'ischémic chaude; 2) entreposage sur glace pendant 48 heures apres flushing avec des solutions électrolytiques; 3) hypotermie par perfusion continuelle. L'ischémie chaude a produit une dégradation rapide de l'ATD en ADP et AMP (en moins de 15 minutes) et une diminution progressive de la quantité totale d'adénine nucléotide (TAN) proportioneile à la durée de la période ischémique. La fonction rénale n'a pas été affectée par des périodes d'ischémie de 15 minutes ou moins. Suite à des périodes ischémiques plus longues cependant, la chutte des taux de TAN et leur niveau de rétablissement après réouverture de la circulation sanguine ont permis de prédire la qualité de la fonction rénale. Après storage au froid ou perfusion continue, la relation entre les taux de TAN et la fonction rénale est disparue. Le flushing à l'aide des solutions de type intracellulaire, malgré sa faible capacité à conserver les taux de TAN s'est avéré une méthode d'entreposage aussi efficace que la perfusion continuelle, laquelle a maintenu des taux normaux de TAN.
Supported by Veterans Administration Research Grant 1519-01. 相似文献
52.
Glans penis leiomyomas are uncommon as primary nonepithelial tumors of the urogenital tract. Only 4 cases are described until today. We saw an other case of an 12 years old boy with a leiomyoma of the glans penis. Clinically the lesion presented as a yellow induration with no symptoms as pain, pruritus or bleeding. The biopsy revealed histological a leiomyoma in the subcutis of the glans penis with no symptoms of malignancy. Because of suspected functional and cosmetic deficiency a total resection was not performed. None of the cases described in the literature showed in the follow up malignancy or recurrency. 18 months postoperatively our patient is furthermore well and without symptoms. Nevertheless the leiomyoma of that localization is rare, this tumor should be included in the differential diagnosis of the neoplasms of the glans penis. 相似文献
53.
Antileukotrienes are a relatively new class of anti-asthma drugs that either block leukotriene synthesis (5-lipoxygenase inhibitors) like zileuton, or antagonise the most relevant of their receptors (the cysteinyl leukotriene 1 receptor [CysLT1]) like montelukast, zafirlukast or pranlukast. Hence, their major effect is an anti-inflammatory one. With the exception of pranlukast, the other antileukotrienes have been studied and marketed in the US and Europe for long enough to establish that they are useful drugs in the management of asthma. Their effects, significantly better than placebo, seem more pronounced in subjective measurements (i.e. symptoms scores or quality-of-life tests) than in objective parameters (i.e. forced expiratory volume in 1 second or peak expiratory flow rate). Also, there is some evidence that these drugs work better in some subsets of patients with certain genetic polymorphisms - probably related to their leukotriene metabolism - or patients with certain asthma characteristics. There are a small number of comparative studies only, and with regard to long-term asthma control differences between the agents have not been evaluated. Nevertheless, their overall effect appears comparable with sodium cromoglycate (cromolyn sodium) or theophylline, but significantly less than low-dose inhaled corticosteroids. Antileukotrienes have been shown to have a degree of corticosteroid-sparing effect, but salmeterol appears to perform better as an add-on drug. Montelukast is probably the most useful antileukotriene for continuous treatment of exercise-induced asthma, performing as well as salmeterol without inducing any tolerance. All antileukotrienes are taken orally; their frequency of administration is quite different ranging from four times daily (zileuton) to once daily (montelukast). Antileukotrienes are well tolerated drugs, even though zileuton intake has been related to transitional liver enzyme elevations in some cases. Also Churg-Strauss syndrome (a systemic vasculitis), has been described in small numbers of patients taking CysLT1 antagonists. It is quite probable that this disease appears as a consequence of an 'unmasking' effect when corticosteroid dosages are reduced in patients with severe asthma once CysLT1 antagonists are introduced, but more data are needed to definitely establish the mechanism behind this effect. Overall, however, the benefits of antileukotrienes in the treatment of asthma greatly outweigh their risks. 相似文献
54.
Peter Albers Roswitha Siener Sabine Kliesch Lothar Weissbach Susanne Krege Christoph Sparwasser Harald Schulze Axel Heidenreich Werner de Riese Volker Loy Erhard Bierhoff Christian Wittekind Rolf Fimmers Michael Hartmann 《Journal of clinical oncology》2003,21(8):1505-1512
PURPOSE: To prospectively assess potential risk factors for relapse in clinical stage I nonseminomatous germ cell tumors of the testis (CS I NSGCT). PATIENTS AND METHODS: From September 1996 to May 2002, 200 patients with CS I NSGCT were prospectively assigned to retroperitoneal lymph node dissection (RPLND), and risk factor assessment was performed within a multicenter protocol. One hundred sixty-five patients had an adequate minimum follow-up of 12 months (mean, 34.5 months) or had pathologic stage II. RESULTS: Pathologic stage II disease was found in 27.9% of patients. Only 0.6% of patients relapsed in the retroperitoneum after confirmation of pathologic stage I disease. With reference pathology, vascular invasion (VI) was most predictive of stage in multifactorial analysis (accuracy, 65.1%). However, the positive predictive value (PPV) of VI to predict patients who have metastatic disease or relapse during follow-up was only 52.7%. With absent VI, low-risk patients had a negative predictive value (NPV) of 76.9%. With a combination of several risk factors, the PPV increased to 63.6% and the negative predictive value increased to 86.5%. CONCLUSION: Even with an optimal combination of prognostic factors and reference pathology, more than one third of patients predicted to have pathologic stage II or relapse during follow-up will not harbor metastatic disease and, therefore, would be overtreated with adjuvant therapy. However, patients at low risk may be predicted at an 86.5% level, and thus, surveillance in highly compliant patients would be a valuable option. For high-risk patients, further reduction of adjuvant treatment is necessary. 相似文献
55.
Sebastian Roka Michael Fiegl Niklas Zojer Martin Filipits Rudolf Schuster Birgit Steiner Raimund Jakesz Heinz Huber Johannes Drach 《Breast cancer research and treatment》1998,48(2):125-133
Previous work from our laboratory demonstrated aneuploidy for several chromosomes by interphase fluorescence in situ hybridization (FISH) in a high proportion of breast cancer specimens. In the literature, only limited data are available concerning chromosome 8 anomalies in breast cancer. To determine chromosome 8 ploidy status in primary and metastatic specimens from 81 breast cancer patients, FISH analysis with a DNA probe recognizing chromosome 8 centromeres was performed. In all primary tumor specimens (n=30), significant proportions of cells were aneuploid exhibiting gain of chromosome 8 copy numbers; in 75% of effusion specimens previously classified as malignant by cytology and/or FISH for various chromosomes (n=40), cell populations aneuploid for chromosome 8 were detected; effusions previously classified non-malignant (n=11) were diploid in 10 cases, whereas one specimen contained rare hyperdiploid cells. Among these cells complex chromosomal aneuploidy could be demonstrated by two-color FISH, suggesting malignancy. Trisomic and tetrasomic clones were predominant in the majority of samples, but a marked intratumor cytogenetic heterogeneity was observed in most cases. Primary tumors and corresponding positive axillary lymph nodes revealed similar distributions of chromosome 8 copy numbers, analogous to previous findings with other chromosomes. This implies that, by using suitable FISH probes after examination of the respective primary tumor, an efficient search for (micro)metastasis might be feasible. 相似文献
56.
Ohne Zusammenfassung 相似文献
57.
58.
59.
Abbreviated chemotherapy with fludarabine followed by tositumomab and iodine I 131 tositumomab for untreated follicular lymphoma. 总被引:4,自引:0,他引:4
John P Leonard Morton Coleman Lale Kostakoglu Amy Chadburn Ethel Cesarman Richard R Furman Michael W Schuster Ruben Niesvizky Daniel Muss Jennifer Fiore Stewart Kroll George Tidmarsh Shankar Vallabhajosula Stanley J Goldsmith 《Journal of clinical oncology》2005,23(24):5696-5704
PURPOSE: To evaluate the safety and efficacy of a sequential chemotherapy plus radioimmunotherapy (RIT) regimen in previously untreated follicular non-Hodgkin's lymphoma. PATIENTS AND METHODS: Thirty-five patients received an abbreviated course (three cycles) of fludarabine followed 6 to 8 weeks later by tositumomab and iodine I 131 tositumomab. RESULTS: After fludarabine, 31 (89%) of 35 patients responded, with three (9%) of 31 patients achieving a complete response (CR). After the full regimen of fludarabine and iodine I 131 tositumomab, all 35 patients responded; 30 (86%) of 35 patients achieved CR, and five (14%) of 35 achieved partial response. After a median follow-up of 58 months, the median progression-free survival (PFS) had not been reached (95% CI, 27 months to not reached), but it will be at least 48 months. The 5-year estimated PFS rate is 60%. Baseline Follicular Lymphoma International Prognostic Index (FLIPI) was significantly associated (P = .003) with PFS. Five of six patients with more than 25% bone marrow involvement at baseline achieved adequate bone marrow cytoreduction to receive standard-dose iodine I 131 tositumomab. Ten (77%) of 13 patients with baseline bone marrow Bcl-2 positivity demonstrated molecular remissions at month 12. Toxicities were manageable and principally hematologic. Two (6%) of 35 patients developed human antimurine antibodies (HAMA) after RIT. CONCLUSION: Use of abbreviated fludarabine before iodine I 131 tositumomab can reduce bone marrow involvement, when needed, to allow the use of RIT and can suppress HAMA responses. This sequential treatment regimen is highly effective as front-line therapy for follicular lymphoma, particularly for low- or intermediate-risk FLIPI patients. 相似文献
60.
Joachim Schuster Hanns-Christian Mahler Susanne Joerg Vinay Kamuju Joerg Huwyler Roman Mathaes 《Journal of pharmaceutical sciences》2021,110(6):2386-2394
Changes in the environment from the drug product to the human physiology might lead to physical and/or chemical modifications of the protein drug, such as in vivo aggregation and fragmentation. Although subcutaneous (SC) injection is a common route of administration for therapeutic proteins, knowledge on in vivo stability in the SC tissue is limited. In this study, we developed a physiologic in vitro model simulating the SC environment in patients. We assessed the stability of two monoclonal antibodies (mAbs) in four different protein-free fluids under physiologic conditions. We monitored protein stability over two weeks using a range of analytical methods, in analogy to testing purposes of a drug product. Both mAbs showed an increase of protein aggregates, fragments, and acidic species. mAb1 was consistently more stable in this in vitro model than mAb2, highlighting the importance of comparing the stability of different mAbs under physiologic conditions. Throughout the study, both mAbs were substantially less stable in bicarbonate buffers as compared to phosphate-buffered saline. In summary, our developed model was able to differentiate stability between molecules. Bicarbonate buffers were more suitable compared to phosphate-buffered saline in regards to simulating the in vivo conditions and evaluating protein liabilities. 相似文献