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1.
Summary Utilizing two types of human renal carcinoma heterotransplanted in nude mice, we investigated the variations in hyperthermic effects (42.5°C for 30 min) caused by differences in tumor type with special reference to variations in tumor vascularity. In the hypovascular JRC1 strain, sporadic vascular dilation was observed throughout the tumors after heating. Destruction of tumor cells was observed mainly in the region of dilation. In the hypervascular JRC11 strain, homogenous vascular dilation was observed immediately after heating, mainly at the periphery of tumors. There was a decrease in the viability of cells in the center of the tumor. Therefore, the hypervascular tumors showed greater destruction mainly at the center where blood circulation was reduced. The range of necrosis was also greatly affected by the extent of vascular dilation caused by heating in hypovascular tumors.  相似文献   
2.
The findings in twenty-two patients with insulinoma were reviewed, as continuous efforts should be made to establish preoperative localization of the tumor. Superselective arteriography and percutaneous, transhepatic portal vein and pancreatic venous catheterization are highly recommended approaches. At the time of surgical intervention, a cautious exploration of the pancreas after thorough mobilization is most important. Recent use of intraoperative ultrasonography increases the likelihood of finding these occult tumors which locate deeply in the head of the pancreas. Apart from the diagnostic problems, we wish to emphasize the high incidence of malignancy (7/22, 31.8 per cent) in our series. Althout patients with malignant isulinoma had a much better prognosis compared to those with a pancreatic ductal malignancy, pancreatic resection with regional lymphnode dissection seems to be a rational procedure. Enucleation can be done when intraoperative findings of the tumor and regional lymphonode indicate no malignant features and no multiple lesions. However, at the first operation, enucleation is still a procedure of choice, even for the malignant insulinoma in the head with a well-defined capsule and no metastatic lesions, the objective being to avoid a duodenopancreatectomy or total pancreatectomy. These data were reported at the 30th Congress of Société Internationale de Chirurgie, Hamburg, Germany, 1983  相似文献   
3.
Repeated oral doses of di-n-butyl phthalate (DBP) to male rats caused a decrease in testicular fructose and glucose and a sloughing of the germ cells on the first day of treatment. On day 2, more severe sloughing was seen and was accompanied by decreases in testicular iron and zinc levels and increases in the level of inositol and cholesterols. The sloughing was followed by atrophy, accompanied by dissociation of the germ cells from the Sertoli cells and reduction of triglycerides, cholesterols and phospholipids containing choline and ethanolamine residues in the testis.  相似文献   
4.
We developed a new method for monitoring the cerebrovascular response to acetazolamide using technetium-99m diethylenetriaminepentaacetic acid human serum albumin (99mTc-DTPA-HSA). We infused 740 M Bq (20 mCi) of 99mTc-DTPA-HSA intravenously and carried out dynamic scanning of the anterior view of the head for 50 minutes. Ten minutes after the start of scanning, 1,000 mg of acetazolamide was injected intravenously. In three normal volunteers, the radioactivity in brain increased for an average of 8 minutes after the injection of acetazolamide and then remained relatively stable. The average of dilatation index [(peak count/the count just before acetazolamide injection-1)x 100] was 16.1. Our method enabled us to observe vasodilation caused by acetazolamide straight, and may be of value in assessing cerebral perfusion reserve easily and quantitatively.  相似文献   
5.
A phase I study of a recombinant gamma interferon (S-6810) was conducted in a cooperative study involving 11 institutions. S-6810 was administered at doses of 2, 4, 8, 12, 32 and 64 X 10(6) U/m2 by one-hour infusion for 5 consecutive days. A total of 40 courses were administered to 31 patients. High fever exceeding 38 degrees C with chills occurred in about 80% of patients. The incidences of other toxicities were fatigue in 50%, gastrointestinal toxicities in 30-40%, and changes in hepatic enzymes and hematologic toxicities in 20-30%. Dose-limiting factors were judged to be hypotension, leukopenia and central nervous toxicity. Maximum tolerated dose was 64 X 10(6) U/m2 and an optimal dose for phase II study was considered to be 6 X 10(6) U/m2 by daily chronic schedule. Blood concentration was highest at the end of infusion, and then decreased rapidly with a biphasic curve. The peak concentrations were elevated by escalation of doses. A partial response was observed in a patient with mycosis fungoides.  相似文献   
6.
7.
The management of clival chordoma remains problematic. We present the case of a 48-year-old woman with clival chordoma who underwent multiple surgeries and radiation therapy, including gamma knife stereotactic radiosurgery (GK-SRS), during a 10-year clinical course. The tumor was initially removed by gross total resection via the trans-sphenoidal approach, followed by external linac radiation therapy. The tumor recurred at the clivus 5 years after the initial operation. After repeated trans-sphenoidal removal of recurrent tumors, she twice underwent GK-SRS for a tumor remnant adjacent to the brainstem. Although this part of the tumor was controlled by GK-SRS, there was further tumor extension toward the sphenoid and maxillary sinuses. Ultimately, lower cranial nerve dysfunction developed due to tumor extension into the lower part of the clivus and the patient died of respiratory failure. Autopsy revealed the tumor to extend from the lower clivus to the bilateral middle fossae. The lower part of the tumor extended to the nasal cavity and to the posterior wall of the pharynx, resulting in compression of the upper pharyngeal region. The tumor around the jugular foramen compressed the lower cranial nerves bilaterally. Tumor cells did not, however, invade the intradural space microscopically. Although chordoma is not biologically malignant, this tumor can show massive extension with destruction of bony structures and extracranial invasion of connective tissues. Therefore, the optimal treatment strategy is to remove the tumor mass as extensively as possible, including normal bony structures and connective tissues surrounding the tumor, using skull base surgical techniques.  相似文献   
8.
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.  相似文献   
9.
Donor specific blood transfusion (DST), given prior to living related kidney transplantation has resulted in significant improvement in graft survival. This improvement, however, has been accomplished with a high rate of adverse sensitization against the donor. In an attempt to reduce the incidence of sensitization, we have employed DST with intermittent coverage of cyclophosphamide. A comparative study was done between 2 methods of DST with or without the coverage of immunosuppressant for prospective kidney transplant recipients from living related donors. In addition, the beneficial effect of DST on graft survival was evaluated in our recent series of living related transplantation using cyclosporine A (CsA) as postoperative immunosuppression. Twenty-nine prospective kidney transplant patients received 200 ml of fresh whole blood 3 times at 2 week intervals from HLA one-haploidentical living related donors. The first 13 patients received DST alone, while the remaining 16 were given cyclophosphamide (CPM 1.5 mg/kg/day) for 3 days prior to each DST. In patients with CPM coverage, 6.3% (1 of 16) developed positive T-warm antibody against donor and 15% of patients (2 of 13) with DST alone developed it. Like-wise 19% (3 of 16) of the former and 38% (5 of 13) of the latter became positive B-warm crossmatch. The difference in sensitization rates between these 2 groups was not statistically significant. Nineteen patients receiving DST were compared to 21 non-DST patients in incidence of acute rejection, graft function and graft survival with the same immunosuppressive regimen, such as CsA, prednisolone, and mizoribine.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Seminal findings and blood hormone levels were studied for evaluating the male reproductive function in patients with spinal cord injury. The patients were divided into 3 groups, namely, 18 patients with complete injury, 5 patients with incomplete injury and 3 patients with dyspermatism. The number of sperms, the rate of movement and rate of deformation were measured for semen obtained by forced ejaculation. The number of sperms was kept at a relatively high level in the three groups, while the rate of movement fell off in all of the three groups. The rate of deformation was highest in the patients with complete injury and lowest in the patients with dyspermatism. As for blood hormone levels, LH, FSH and Testosterone (hereinafter referred to as TES) were determined by the RIA. The cases were classified into those in the acute stage and those in the chronic stage 3 months after sustaining injury for a comparative study. The subjects consisted of 27 cases in the acute stage and 47 cases in the chronic stage. For 8 patients in the acute stage, the blood hormone levels were determined even in the chronic stage and follow-up observations were made on the changes in the levels. The FSH level was low in both stages, while LH and TES tended to increase in the chronic stage. Particularly, the TES level was elevated in all the cases in the follow-up observations made in 8 patients. From the results mentioned above, transient disturbance of the interstitial function is suggested as the mechanism of male gonadal disturbance due to spinal cord injury.  相似文献   
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