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1.
Mean cell volume and mean cell water content were examined in Plasmodium yoelii-infected mouse erythrocytes by gas chromatography and 3H-sucrose. Mean cell volume increased by 16% in infected erythrocytes with late trophozoites and schizonts. Mean cell water content further increased by 23% in the infected erythrocytes. Measurement of the erythrocyte potassium and sodium concentrations by an atomic absorption spectrophotometer revealed that the infected erythrocytes contained highly elevated sodium and slightly reduced potassium levels when calculated per single erythrocyte. It is suggested that membrane transport processes of sodium and potassium are changed in P. yoelii-infected erythrocytes and that a passive inflow of sodium takes place, which results in an increase in intra-erythrocytic water content.  相似文献   
2.
Human TNF was detected fairly recently and at present the anti-tumor activity of human recombinant TNF is being examined against various malignant tumors of human origin. In the present study, we report the anti-tumor activity of recombinant human TNF against human malignant glioma cell lines in vitro and in vivo, in addition to its combined effects with HuIFN-beta. The in vitro study was conducted as follows. Thirteen human glioma cell lines were exposed to 100 U/ml TNF, 1,000 IU/ml HuIFN-beta, or both, and the suppression rate was calculated on days 3, 5 and 7. In the in vivo study, nude mice carrying a human glioma cell line, KMS II, in the subcutaneous tissues were divided into groups and drugs were administered intratumorally as described below. 1) control, 2) TNF 5,000 U single administration, 3) TNF 5,000 U, intermittently administered (once/week for two weeks), 4) TNF 5,000 U, continuously administered (3/week for two weeks), 5) HuIFN-beta 50 X 10(4) IU (3/week for two weeks), and 6) combination of 4) with 5). Results of the in vitro study revealed some suppressive effects on proliferation of tumor cells on day 7 in all 13 glioma cell lines examined with 100 U/ml TNF. And also, especially in 8 of 13 cell lines, the suppression rate was more than 30%. The suppressive effects of TNF were augmented by combined use of HuIFN-beta in all cell lines, giving a range of suppression of 67.8 to 99.3%. The in vivo study revealed that the mean tumor weight ratios (control = 100%) on day 19 (the end of the experiment) were as follows; single administration of TNF: 41.3%, intermittent: 46.7%, continuous: 26.7%, HuIFN-beta: 65.9%, combination: 18.5%. Statistical analysis disclosed significant suppressive effects on tumor proliferation between the control group and 3 TNF-administered groups (single, intermittent, and continuous) and that suppression in the continuously administered group was more severe in comparison with the group given single administration. Moreover, it was suggested that combination therapy with TNF and Hu IFN-beta was more effective than a single therapy with TNF only or HuIFN-beta only. From the results described above, it was found that human recombinant TNF had some cytotoxic effects against human malignant gliomas in vitro and in vivo, although the degree of cytotoxicity was not always higher in comparison with the effects of TNF.  相似文献   
3.
Minimum incision endoscopic nephrectomy for giant hydronephrosis   总被引:1,自引:0,他引:1  
Five consecutive patients with symptomatic giant hydronephrosis underwent minimum incision endoscopic nephrectomy. The originally huge renal specimen was retroperitoneally mobilized using both of endoscopy and direct vision, without the use of trocar ports or gas insufflation, via a single minimum incision that narrowly permitted extraction of the specimen. The specimen was successfully extracted from the incision in all patients. Technically, proper deflation of the hydronephrotic sac facilitates mobilization and enables extraction of the specimen. Median (range) size of incision, operative time, and estimated blood loss were 4 cm (3-5), 205 min (156-222), and 210 mL (110-350), respectively. No patient required blood transfusion or encountered operative complications. Postoperative convalescence was short and uneventful; all patients resumed oral intake and ambulance on the day following surgery, and were physically dischargeable from hospital after 2-3 postoperative days. Thus, this technique is a feasible, minimally invasive and safe procedure for symptomatic giant hydronephrosis.  相似文献   
4.
OBJECTIVES: Vesicoureteral reflux (VUR) is the most common congenital urinary tract anomaly. This disease can pose a major threat to the kidneys as twenty percent of patients with endstage renal disease are reported to have VUR. Although genetic studies for uroplakin III (UPIII) have been reported recently, no study has focused on UPIII gene expression in VUR patients. We describe here the up-regulation of UPIII mRNA in exfoliated urinary cells from primary VUR patients. METHODS: A real-time RT-PCR for UPIII mRNA was performed on exfoliated urothelial cells from 18 primary VUR and 38 control samples. UPIII mRNA copies were calculated for each sample. The statistical differences were assessed by the Mann-Whitney U test. Receiver operator characteristic curves were constructed for analysis of the diagnostic values. RESULTS: UPIII mRNA was found to be up-regulated to a greater extent in VUR than in control exfoliated urinary cells (mean +/- SE: 497.0 +/- 178.5 copies vs. 69.0 +/- 10.0 copies, respectively, P < 0.001). In evaluating the measurement of urinary UPIII mRNA as a screening test for VUR, the sensitivity was 77.8% and the specificity was 76.3% by the best diagnostic cutoff point. CONCLUSIONS: This is the first report demonstrating up-regulation of UPIII in mRNA levels in VUR patients. We submit that the quantitative measurement of urinary UPIII mRNA has a potential of developing into the first non-invasive screening test for VUR.  相似文献   
5.
Since 1998, we have performed minimum incision endoscopic surgery (MIES) for renal cell carcinoma (RCC). For seven dialysis patients with bilateral RCC, we have performed sequential bilateral MIES radical nephrectomy. It was carried out by retroperitoneal approach through a single minimum incision that narrowly permitted extraction of the specimen using endoscopy and direct stereovision, without trocar ports, without gas insufflation and without the insertion of the hands of operators into the operative field. Although six of the seven patients had multiple complications in addition to chronic renal failure (CRF), bilateral kidneys were successfully removed by sequential MIES radical nephrectomy without major operative complication. Postoperative recovery was prompt with all patients resuming oral feeding and walking by the second postoperative day. Sequential bilateral MIES radical nephrectomy, leaving the peritoneal cavity intact and without imposing circulatory stress caused by gas insufflation, is a feasible treatment for bilateral RCCs in dialysis patients.  相似文献   
6.
The effect of dietary manipulation on global tooth uptake of 47Ca-chloride was evaluated in three rat models of metabolic bone diseases verified by histologic bone study. The 24-hr tooth uptake of 47Ca-chloride was significantly decreased in the osteomalacic group, and was increased in the osteoporotic group at the fourth week. Tooth uptake closely paralleled femoral uptake at a correlation coefficient of 0.73 (p less than 0.01). The uptake of 47Ca-chloride in tooth was found to be more affected by dietary manipulation than that in femur in our rat models.  相似文献   
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Normal epithelial and carcinoma cells of human bladder were investigated for the cytokeratin which is one of the intermediate filaments and comprises cytoskeleton using the immunofluorescence method. Carcinoma cell lines used were JTC-30, JTC-32, HUB-41 and T-24. In normal urothelium, keratin fibers were fine and straight with unchanged diameter and distributed regularly in the cytoplasm. By contrast, keratin fibers in bladder carcinoma cells were kinked and changed in diameter and were distributed irregularly in the cytoplasm. The above findings were most obvious in T-24 which formed undifferentiated carcinoma when transplanted to nude mice, and keratin fibers were dominantly located in the perinuclear area. The changes of keratin fibers appeared to be parallel to the grade of histological anaplasia of the tumor formed by implantation of bladder carcinoma cell line cells to nude mice. These observations suggest that the morphology of cytokeratin is a useful indicator for evaluating the grade of malignancy in transitional cell carcinoma.  相似文献   
10.
Observational and some experimental data suggest that hepatitis C virus can manifest in a variety of disease processes outside the liver. The links between hepatitis C virus and membranoproliferative glomerulonephropathy, porphyria cutanea tarda, lichen planus, cryoglobulinemia, diabetes mellitus, B-cell non-Hodgkin’s lymphoma, and thyroiditis are critically reviewed. Based on the available evidence, recommendations for the clinical approach to patients with extrahepatic diseases are discussed.  相似文献   
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