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81.
Automated noninvasive blood pressure (NIBP) monitors have found widespread use both inside and outside clinical environments in recent years. Present methods for evaluating the measurement accuracy of this class of devices involve population studies that are meticulous, time-consuming and costly. These methods are also impractical for routine evaluation. NIBP simulators offer an alternative approach to evaluating automated NIBP monitors without directly using human subjects. They enable evaluation to be carried out on demand with little training, providing a safe and convenient way for manufacturers and hospitals to validate the performance of both new and existing monitors. 相似文献
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Prostatic neoplasia in transgenic mice with prostate-directed overexpression of the c-myc oncoprotein 总被引:3,自引:0,他引:3
BACKGROUND: Promoter elements within the 5' DNA region of the rat C(3)1 gene have been shown to direct prostate-specific expression of gene products when they are fused through recombinant DNA procedures and used to produce transgenic mice. In order to test the in vivo effects of chronic overexpression of the mouse c-myc protooncogene on the prostate glands of transgenic mice, we created several lines of C(3)1-c-myc transgenic mice and then examined the phenotype of males with this genetic alteration. METHODS: The modified promoter and 5' region of the rat C(3)1 gene was fused to the coding region of the mouse c-myc gene using recombinant DNA techniques. This DNA was used to create three different founder lines of transgenic mice. Tissues from males and females heterozygous for the transgene were examined for expression of the recombinant mouse c-myc mRNA by an RNase protection assay. Prostates from males were examined for expression of recombinant c-myc mRNA by in situ hybridization. Thin sections of fixed ventral prostates from males were analyzed by microscopy for histological abnormalities. RESULTS: Three different lines of transgenic mice were obtained from these procedures. These mice demonstrated expression of recombinant mouse c-myc mRNA in the testis and ventral prostates of males and in the uterus of females. In situ hybridization demonstrated that the epithelial cells were the source of recombinant c-myc expression in the ventral prostates of the transgenic lines. Microscopic analysis of the ventral prostates from these mice demonstrated abnormalities in epithelial cell morphology seemingly typical of an intraepithelial neoplasia-like phenotype. However, none of the males of any of the lines developed overt prostatic adenocarcinoma over their lifetimes. CONCLUSIONS: Chronic overexpression of c-myc in the ventral prostate epithelial cells of C3(1)-c-myc transgenic mice leads to the development of epithelial cell abnormalities similar to those seen in low-grade prostatic intraepithelial neoplasia in humans. These abnormalities were not found to progress to adenocarcinoma over the lifetimes of the transgenic mice, suggesting the need for additional oncogenic changes in the pathway to prostatic adenocarcinomas. Furthermore, our cumulative experience with the use of the C3(1) gene promoter in the generation of transgenic mice suggests that the probasin promoter element provides a much more specific and effective means to target transgenes to the prostate glands of mice. 相似文献
84.
85.
Francesco Izzo Paolo Marra Gerardo Beneduce Giuseppe Castello Paolo Vallone Vincenzo De Rosa Franco Cremona C Mark Ensor Frederick W Holtsberg John S Bomalaski Mike A Clark Chaan Ng Steven A Curley 《Journal of clinical oncology》2004,22(10):1815-1822
PURPOSE: Recently, we reported that a large number of human hepatocellular cancer (HCC) cell lines were auxotrophic for arginine. Here we report the results obtained with the amino acid-degrading enzyme arginine deiminase (ADI) conjugated to polyethylene glycol (ADI-SS PEG 20,000 mw) as a means of lowering plasma arginine to treat HCC. The study was a cohort dose-escalation phase I/II study. PATIENTS AND METHODS: Pharmacodynamic studies indicated an ADI-SS PEG 20,000 mw dose level of 160 U/m(2) was sufficient to lower plasma arginine from a resting level of approximately 130 micromol/L to below the level of detection (< 2 micromol/L) for more than 7 days, a dose later defined as the optimal biologic dose. All patients were to receive three cycles at the optimum biologic dose. RESULTS: This therapy was well tolerated, even in patients who had no detectable plasma arginine for 3 continuous months of therapy. Of the 19 patients enrolled, two had a complete response, seven had a partial response, seven had stable disease, and three had progressive disease. The median survival for the 19 patients enrolled on this study was 410 days, with four patients still alive at present (> 680 days). CONCLUSION: Elimination of all detectable plasma arginine in patients with HCC was well tolerated and seemed to be effective in the treatment of some patients with HCC. Further testing of ADI-SS PEG 20,000 mw in a larger population of individuals with HCC as well as other human tumors auxotrophic for arginine is warranted. 相似文献
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87.
This case report describes a primary hepatic leiomyoma presenting as a mass lesion detected on ultrasonography of the abdomen in an asymptomatic hepatitis B carrier on routine surveillance. Primary leiomyomata of the liver are rare occurrences, with only 9 cases reported in the literature. The presenting features of primary hepatic leiomyomata and diagnostic approach towards such lesions are discussed. The significance of such tumours in the immunocompromised is also mentioned. 相似文献
88.
Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis. 相似文献
89.
T. F. Fok P. C. Ng W. Wong C. H. Lee K. W. So 《Archives of disease in childhood. Fetal and neonatal edition》1997,76(2):F123
AIMS—To describe the short term effect of high frequency oscillatory ventilation on infants with severe abdominal distension who could not be conventionally ventilated.METHODS—Eight infants (25 to 38 gestational weeks, birthweight 600-3200 g, postnatal age 1 to 190 days) with a variety of intra-abdominal pathologies, resulting in severe abdominal distension and failure of conventional ventilation, were studied.RESULTS—The oxygenation status of all infants significantly improved within an hour of changing from conventional to high frequency oscillatory ventilation. Infants who were hypercapneic on conventional ventilation also showed a reduction in PaCO2. As a group, the mean (SD) PaO2/FIO2 improved from 4.99 (0.98) kpa to 11.55 (3.8) kpa (P = 0.002), and the PaCO2 from 6.48 (2.12) kpa to 4.89 (1.22) kpa (P= 0.028). These improvements were sustained throughout the next 48 hours.CONCLUSION—High frequency oscillatory ventilation seems to be an effective rescue measure for infants with respiratory failure secondary to increased intra-abdominal pressure. 相似文献
90.
Biliary hamartomas associated with biliary stones presenting as multiple microabscesses: case report
A 63-year-old men suffered from fever, jaundice, and right upper quadrant pain for 1 week. Biliary stones with biliary tract infection were diagnosed. He was treated with parenteral antibiotics. However, abdominal ultrasonography showed multiple hyperechoic lesions in both lobes, and infiltrating hepatocellular carcinoma was suspected initially. Numerous hypervascular nodular-enhancing lesions were revealed by computed tomography. Magnetic resonance imaging further disclosed numerous tiny cystic lesions with peripheral enhancement. Exploratory laparotomy was performed for biliary calculi and probable underlying malignancy. Cholecystectomy, choledocholithotomy, and liver wedge biopsy were done. The pathology revealed bile duct hamartomas with microabscess formation. The past literature about biliary hamartomas is reviewed. 相似文献