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991.
Twenty-nine patients with advanced leukemias (median age 34 years) received histocompatible sibling marrow that had been depleted of T cells by ex vivo incubation with anti-CD5 monoclonal antibody-ricin immunotoxin (T101-R) for the purpose of graft-versus-host disease prophylaxis. Donor cell engraftment was documented in 28/29 patients by DNA restriction fragment length polymorphisms. In this pilot study the dose of T101-R incubated with donor marrow was increased in a stepwise manner from 300 ng (10 patients) to 600 ng (5 patients) to 1000 ng immunotoxin (IT)/10(7) bone marrow mononuclear cells (14 patients) in an attempt to achieve more effective GvHD prophylaxis. A statistically significant reduction in acute GvHD was achieved for patients receiving marrow pretreated with 1000 ng of immunotoxin (34%) compared to recipients of BM treated with 300 ng immunotoxin (100%, P = 0.0004). T-depleted marrow samples were evaluated for residual T cell activity using several in vitro assays including proliferation to the purified mitogen PHA (HA-17) and in mixed lymphocyte culture (MLC), T cell cytotoxicity, a limiting dilution assay for detecting precursors of proliferating T cells (LDApPTL), and phenotypic analysis of viable T cells expanded in 16-day culture with interleukin 2. The extent of T cell depletion determined by LDA assay varied widely at each immunotoxin concentration used. Thus, there was no correlation between the dose of T cells infused and subsequent GvHD. Phenotyping of lymphocytes recovered from immunotoxin-treated marrow demonstrated that residual T cells were CD5 negative in all cases tested. The only in vitro parameter that predicted subsequent acute or chronic GvHD was the demonstration of viable CD5 negative lymphocytes with T cell phenotype (CD2, CD3, and/or CD7 positive) after 16-day culture with IL-2 of the T-depleted bone marrow. We observed that such CD5 negative cells expressing other T cell markers have cytotoxic function and speculate that these cells may be capable of mediating GvHD in allogeneic transplantation.  相似文献   
992.
Verapamil increases the serum-digoxin concentration (SDC) in digoxin treated normals due to a compromised renal and extrarenal clearance. In chronic hemodialysis patients (CHD-patients) treated with digoxin where the renal elimination is diminished, verapamil has been shown to cause substantial increases of SDC with risk of digoxin intoxication. The effect of verapamil treatment on SDC in 8 nearly anephric (Uvol less than 1 l/d) CHD-patients on digoxin treatment was assessed. The patients were continuously treated with verapamil for two periods of two weeks at two dosage levels, 120 mg/d and 240 mg/d, whereafter verapamil was withdrawn. SDC and serum-verapamil were measured weekly. The SDC increased from 1.1 mmol/l to 1.7 mmol/l (p less than 0.05, N = 7) during the first two weeks. Increasing the dose of verapamil to 240 mg/d did not cause a further increment in SDC; on the contrary, the mean SDC decreased. The SDC increments varied between 0 and 200% of baseline values. We conclude that verapamil treatment decreases digoxin clearance in CHD-patients and that the influence of verapamil on SDC in CHD-patients shows great interindividual variation with no close dose dependency and decreases to pretreatment level in 2-3 weeks.  相似文献   
993.
Photodynamic therapy (PDT) is the local destruction of tissue by the interaction of light with a previously administered photosensitizer producing a photochemical effect. This technique has been demonstrated to permit the eradication of small tumours in experimental and clinical practice, with clear biological advantages. This paper reviews PDT experience in gastroenterology, together with concepts currently under experimental investigation.  相似文献   
994.
In the experiment on dogs and in patients with duodenal ulcer disease, it was established that the regulation of acid production besides the vagal nerves was mediated by the intragastric gastrin transport with the blood flow. A method of preoperative diagnosis of the intensity of intragastric blood flow permitting to define more accurately the indications for the choice of a method for surgical treatment has been developed. Supplementation of the selective proximal vagotomy with circular mucosectomy at the boundary between the antrum and body of a stomach enhances the effectiveness of operation due to reduction of the antral gastrin influence on the acid-producing zones of the stomach.  相似文献   
995.
996.
The results of resection of the liver in repeated operations on patients with parasitic disease of the liver are discussed. Operations were conducted on 22 patients with alveococcosis and 7 patients with echinococcosis. By means of the method of atypical liver resection radical operations were performed on 20 patients (69%) and palliative resections of the liver in 9 patients (31%). The palliative resections were combined with cryodestruction of the remaining parasitic tissue, which improved the therapeutic effect significantly and prolonged the patients' survival. The volume of the resection ranged from a segment to one half of the liver. The fatality rate was 6.8%.  相似文献   
997.
998.
999.
Although the cause varies widely, we recently experienced a case of constrictive pericarditis of which cause seemed to be traumatic as described below. The patient was a 62-year-old man having a history of epigastric trauma about 20 years ago. Since then, palpitation appeared and he was recently hospitalized in our department for the purpose of receiving an operation under the diagnosis of constrictive pericarditis. At operation, a hematoma was found in the pericardial region, which was considered to have been caused by trauma in the past. Less reports have so far been available concerning trauma-induced constrictive pericarditis and this case thus seemed to be of rarity as well.  相似文献   
1000.
Nine main organs in the mouse were studied by ESR spectroscopy at 77K. Manganese ions were readily detected in the pancreas, small intestine, stomach and kidney. In particular, the pancreas gave strong ESR signals for the transition metal, suggesting that Mn(II) plays an important role in pancreatic function. All organs reveal different ESR spectra indicating organ specificity. C-centered radical, R-OO radical and C0Q10 or ascorbate radical are stable in the tissue. In the brain, heart and pancreas, N-centered radical heme-NO adduct was detected at 6 and 24 h after excision since common process is involved in tissue degeneration and ESR is sensitive to proteolysis and necrosis of tissues. In endotoxemia and/or CDE-diet-induced pancreatic lesions, R-OO radical and Mn(II) ion were detected in the signal at 77K. By the spin-trapping method (DMPO) at 25 degrees C, DMPO-OH adduct and 3-Line and 6-Line were detected in CDE diet-induced acute pancreatitis. These results suggest that damaged pancreatic tissues are in a highly oxidative environment that probably contains oxygen radicals, and that free radicals are considered to play an important role in the development of pancreatic lesions.  相似文献   
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