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Previously, we reported that allogeneic skin grafts were rapidly rejected by CD28 and CD40 ligand double deficient mice mediated by CD8+ T cells. These results indicated that some elements in addition to CD28- and CD40-mediated costimulation provide stimulatory signals for the activation of donor-specific CD8+ T cells. In this report, we investigated the role of inflammation associated with transplantation on costimulation-independent priming of CD8+ T cell during graft rejection. B6 RAG1 KO mice were transplanted with BALB/c-skin and adoptively transferred with syngeneic CD8+ T cells the same day or 50 days after transplantation. When blockade of CD28- and CD40-mediated costimulation failed to prevent acute rejection of freshly transplanted skin grafts, it efficiently delayed rejection of well-healed skin grafts. These results showed that factors associated with transplantation have essential roles in inducing costimulation blockade-resistant allograft rejection. Costimulation blockade failed to prevent acute graft-infiltration of NK cells and increasing expression of intragraft IL-12 and IL-15. These factors may trigger the graft-infiltration and priming of CD8+ T cells to induce costimulation blockade-resistant allograft rejection.  相似文献   
3.
We have developed a new method of total intravenous anesthesia with droperidol, fentanyl and ketamine and have administered it to more than 400 surgical patients, ranging in ages from 4 to 80 years. Cardiac and neurosurgical patients were excluded. After establishing a routine monitoring, droperidol 0.06-0.1 ml.kg-1 was slowly given. After 5 minutes, fentanyl 1-2 micrograms.kg-1 and ketamine 1.0-1.5 mg.kg-1 were slowly administered intravenously. Trachea was intubated following intravenous succinylcholine. A total dose of 5-15 micrograms.kg-1 of fentanyl was given intravenously with a continuous infusion of ketamine 2 mg.kg-1.hr-1 during surgical procedure. Air and O2 (FIO2 0.30-0.35) were given and muscle relaxation was achieved with necessary dose of intravenous pancuronium or vecuronium and no inhaled anesthetic was given. Total intravenous anesthesia has many advantages such as no air pollution in the operating theatre, empty bowels, no organ (hepato-renal) toxicity, good peripheral perfusion and low cost, while this method has several disadvantages to overcome such as hypertension. There are many anesthetic agents for total intravenous anesthesia. However, sufentanil, alfentanil and propofol are not available. Droperidol, fentanyl and ketamine are the best combination for this purpose in Japan so far.  相似文献   
4.
OBJECTIVE: The baseball-diamond principle is generally used for trocar placement during video-assisted thoracic surgery; however, we are unable to treat all peripheral lung lesions using this principle. Therefore, we have developed another method for determining trocar placement based on a modification of the conventional principle. We have termed this method the triangle target principle. This report describes the instrument positioning that we now use for many video-assisted thoracic surgical procedures. METHODS: We position 3 trocars in an equilateral triangle, with the target lesion at the apex. One vertex of the base becomes the site of the first trocar placement for introduction of the thoracoscopic camera. Another vertex of the base becomes the site for the second trocar for forceps or the endoscopic stapler. The third trocar is for forceps and is inserted to create the vicinity of target lesion. Four types of the triangle target principle were developed according to sites of the target lesion. RESULTS: Between January 2000 and December 2002, we used this principle for 161 patients who underwent video-assisted thoracic surgery and all intrathoracic lesions were accessible except in 3 patients requiring intraoperative modifications. CONCLUSIONS: We conclude that video-assisted thoracic surgery by this principle is more effective and easier than the conventional principle to treat intrathoracic disease.  相似文献   
5.
Intraosseous ganglia of the glenoid are rare, and their etiology is unknown. This report describes a case of an intraosseous ganglion about to cause fracture of the glenoid. The patient was a 61-year-old woman with a painful left shoulder with a limited range of motion. Her symptoms did not improve after non-operative treatment. Arthroscopic examination showed a cartilage defect and erosion in the posteroinferior portion of the glenoid, behind which computed tomography (CT) showed a cystic lesion of the glenoid. There was no communication between the cyst and the joint space. The patient was treated by curettage and an autogenous cancellous bone graft from the iliac crest. Two years after the operation, the patient was almost free from pain, and CT showed good integration of the bone graft.  相似文献   
6.
We report an 18-month-old boy with the association of pectus excavatum and tetralogy of Fallot (TOF). We successfully performed simultaneous pectus repair using sternal elevation without any prosthetic support and total correction of TOF after a prior modified Blalock-Taussig shunt. Retracting a divided costo-sternal complex with a rectus abdominal flap away from the operative field before the cardiac operation provided excellent surgical exposure. The modified Blalock-Taussig shunt prior to the combined repair prevented life-threatening hypoxic spells during dissection of the deformed sternum and costochondral cartilages before institution of cardiopulmonary bypass.  相似文献   
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The monoclonal antibody (MAb) A7 has been used to treat patients with colorectal or pancreatic carcinoma with encouraging results. We therefore determined if MAb A7 would also react with gastric carcinoma cell lines. MAb A7 reacted with seven of eight gastric carcinoma cell lines tested. The intensity of the reaction, measured by flow cytometry, was equal to that of WiDr (colon) and HPC-YS (pancreas) cell lines. In nude mice bearing xenografts of the MAb A7-reactive gastric cancer line MKN45, the percentage injected dose of MAb A7 per g of tumour tissue on day 7 was 9.79; this value was 77% of that on day 1. The in vivo tumour-to-blood ratio of MAb A7 was 2.77 on day 7. Therefore, MAb A7 has long-term retention at binding sites as well as a high probability, high intensity and high specificity of reactivity against gastric cancer, which make it an ideal drug carrier for immunotargeted chemotherapy and immunodiagnosis.  相似文献   
9.
We report a 64-year-old Japanese woman with recurrent ischemic strokes and progressive dementia without any cardiovascular risk factors. Her first stroke was at 45 years old, and she has a family history of ischemic strokes compatible with an autosomal dominant trait. Marked leukoaraiosis and multiple lacunar infarcts were shown on brain MR images, and no atherosclerotic changes were observed in her extra- and intra-cranial arteries by cervical arterial echography and intracranial MR angiography. Excluded other inherited or metabolic diseases causing leukodystrophy by examination of her blood samples, her disease was diagnosed as CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and lekoencephalopathy). We demonstrated granular osmiophilic materials (GOM) on the wall of small arteries from a biopsied peripheral nerve tissue specimen and detected a mutation Arg169Cys of Notch 3 gene. Many CADASIL patients have been reported and over 28 kinds of mutations of the Notch 3 were identified in western countries, while few CADASIL patients have been reported in Japanese people. Among them, eleven CADASIL families have been reported and only five mutations (Arg133Cys, Cys174Phe, Arg213Lys, Arg90Cys and Arg141Cys) have been determined so far. The mutation of Notch 3 in our patient was determined as Arg169Cys, and this is the first report on a Japanese patient with CADASIL due to this mutation.  相似文献   
10.
The synthesis of methyl methacrylate/styrene copolymer bearing overwhelmingly bromine and the 2-carbomethoxyallyl group (CH2?C(COOCH3)CH2? ) at the α- and ω-termini instead of the fragment of the initiator with reduced molecular weight was investigated by using methyl α-(bromomethyl)acrylate as chain transfer agent through the addition-fragmentation mechanism. The molecular weight of the copolymer was effectively decreased with bromomethylacrylate, and the unsaturated end groups quantitatively bound to two types of the monomeric units were differentiated by means of 1H NMR spectroscopy. Equations estimating the reactivities of methyl α-(bromomethyl)acrylate towards polystyrene and poly(methyl methacrylate) radicals were derived. Methyl α-(bromomethyl)acrylate was found to be more reactive toward the poly(methyl methacrylate) radical than the polystyrene radical by a factor of 0,62.  相似文献   
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