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121.
Girish J. Patel Robert P. Schatz Spiro M. Constantinides Harbans Lal 《Biochemical pharmacology》1975,24(1):57-60
In mice, intraperitoneal administration of desipramine (12·5–100 mg/kg) or pargyline (25–200 mg/kg) reliably elevated the brain concentration of gamma-aminobutyric acid in a dose-dependent manner. In addition, both drugs caused hypothermia and a prolongation of sodium barbital induced narcosis. None of those effects of desipramine, but not of pargyline, were seen when the treated animals were placed in high ambient temperature to prevent drug-induced hypothermia. 相似文献
122.
Kalyanasundaram Venkataraman Robert Siegel Sun June Kim John W. Allen 《The American journal of cardiology》1978,41(5):952-955
Five patients with musical murmurs were studied noninvasively with simultaneous echocardiography and phonocardiography. Three patients had aortic regurgitation, one mitral regurgitation and one tricuspid regurgitation. The frequency of the musical murmurs ranged from 40 to 158 cycles/sec. The patient with tricuspid regurgitation manifested an inspiratory honk. Simultaneous echo-phonocardiography revealed regular valve leaflet flutter (aortic, mitral or tricuspid) at a frequency identical to that of the simultaneously recorded musical murmur. This study demonstrates that echocardiography is a useful noninvasive tool in identifying the site of origin of musical murmurs. 相似文献
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124.
Manganese superoxide dismutase overexpression inhibits the growth of androgen-independent prostate cancer cells 总被引:9,自引:0,他引:9
Venkataraman S Jiang X Weydert C Zhang Y Zhang HJ Goswami PC Ritchie JM Oberley LW Buettner GR 《Oncogene》2005,24(1):77-89
This study investigates the role of the antioxidant enzyme manganese superoxide dismutase (MnSOD) in androgen-independent human prostate cancer (PC-3) cells' growth rate in vitro and in vivo. MnSOD levels were found to be lower in parental PC-3 cells compared to nonmalignant, immortalized human prostate epithelial cells (P69SV40T). To unravel the role of MnSOD in the prostate cancer phenotype, PC-3 cells were stably transfected with MnSOD cDNA plasmid. The MnSOD protein and activity levels in clones overexpressing MnSOD were increased seven- to eightfold. These cell lines showed elongated cell doubling time, reduced anchorage-independent growth in soft agar compared to parental PC-3 (Wt) cells, and reduced growth rate of PC-3 tumor xenografts in athymic nude mice. Flow cytometric studies showed an increase in membrane potential in the MnSOD-overexpressing clone (Mn32) compared to Wt and Neo cells. Also, production of extracellular H(2)O(2) was increased in the MnSOD-overexpressing clones. As determined by DNA cell cycle analysis, the proportion of cells in G(1) phase was enhanced by MnSOD overexpression. Therefore, MnSOD not only regulates cell survival but also affects PC-3 cell proliferation by retarding G(1) to S transition. Our results are consistent with MnSOD being a tumor suppressor gene in human prostate cancer. 相似文献
125.
126.
Cardiac tumours: diagnosis and management 总被引:9,自引:0,他引:9
Primary cardiac tumours are rare, with an autopsy incidence ranging from 0.001% to 0.030%. Three-quarters of these tumours are benign and nearly half of the benign tumours are myxomas. Metastases to the heart are far more common than primary cardiac tumours. Primary cardiac tumours present with one or more of the symptoms of the classic triad of: cardiac symptoms and signs resulting from intracardiac obstruction; signs of systemic embolisation; and systemic or constitutional symptoms. They are diagnosed by use of transthoracic and transoesophageal echocardiograms, MRI, and CT scan. Whereas surgery is indicated in patients with benign tumours, systemic chemotherapy is indicated in those who have widespread or unresectable malignant disease, and chemotherapy and radiotherapy are usually combined in treatment of patients with primary cardiac lymphomas. The prognosis after surgery is usually excellent in the case of benign tumours but is unfortunately still limited in localised malignant diseases. Patients with sarcomas live for a mean of 3 months to 1 year, and those with lymphomas live up to 5 years if treated, but usually die within 1 month if untreated. 相似文献
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128.
Intussusception in adults is a rare cause for intestinal obstruction and is usually secondary to some lesion in the gastrointestinal tract GIT. We report a case of intestinal obstruction due to ileo-colic intussusception; an inflammatory fibroid polyp formed the leading edge of the intussusceptum, which is a rare polypoidal lesion of the GIT. 相似文献
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130.
Although acetaminophen (APAP)-associated liver injury is well recognized, there are few reports describing APAP nephrotoxicity, and most of them are single cases. It has also been suggested that N-acetylcysteine (NAC), used to treat the hepatotoxicity, may be harmful to the kidneys. To examine this contention and to determine whether renal involvement in APAP poisoning is at all common, we analyzed the incidence and outcome of acute renal dysfunction in patients hospitalized for APAP overdose reported to our regional poison center over a year. Eleven APAP-poisoned patients had elevated liver function tests; nine of them had azotemia. Those with higher AST levels tended to be younger and to have lower APAP levels on admission. Two patients with acute renal injury died after admission. The other seven patients with renal dysfunction recovered in 2 to 7 days. Six of these received NAC; their mean serum creatinine fell from 3.2 +/- 2.0 versus 1.7 +/- 0.9 mg/dL (p < 0.05). We conclude that acute renal failure is not uncommon in APAP poisoning and appears to be unrelated to the degree of liver injury. NAC therapy did not seem to worsen nephrotoxicity. 相似文献