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1.
An extracellular lipase, active on water-insoluble triacylglycerols, has been isolated from Penicillium cyclopium. The purified enzyme has a molecular mass of 29 kDa by gel filtration and SDS-polyacrylamide gel electrophoresis. It hydrolyzes emulsions of tributyrin, trioctanoin, and olive oil at the same rate as pancreatic lipase and shows very low activity against partial acylglycerols (monooctanoin and dioctanoin) and methyl esters. It is stable at 35 degrees C for 60 min and has maximal activity in a pH range of 8-10. Hydrolysis of triacylglycerols by P. cyclopium lipase is inhibited by detergents such as Triton X-100. Comparison of the sequence of the 20 first amino acid residues of P. cyclopium triacylglycerol lipase with other Penicillium lipases indicates a high homology with previously characterized lipases produced by P. expansum and P. solitum which are enzymes of comparable size and substrate specificity. Conversely, homology between P. cyclopium lipase and P. simplicissimum lipase, a nonspecific lipolytic enzyme, is low. Penicillium cyclopium triacylglycerol lipase shows no homology with P. camembertii lipase which is specific to monoacylglycerol and diacylglycerol.  相似文献   

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Fatty acid oxidation has been studied with the tritium release assay in cultured fibroblasts from patients with defects in beta-oxidation and in the mitochondrial respiratory chain. Cells from all patients with beta-oxidation defects and cells from 10 of 16 patients with respiratory chain defects showed an impairment of fatty acid oxidation. The result of the tritium release assay is not only dependent on the proper function of the beta-oxidation cycle but is also influenced by the reoxidation of reduced cofactors. The assay can thus be used to study the expression of respiratory chain defects in cultured fibroblasts.  相似文献   

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79 cases of adrenal tumors were treated in our hospital from 1985 to Aprit. 1994. 30 of them had nonfunctional adrenal tumors. Data have shown that nonfunction adrenal tumor is not unusual. The detection rate of the disease will increase with the development and popularization of medical imageology which consists of B-ultrasonography and CT scanning etc. In this article, the diagnosis and treatment of this disease were discussed in detail with a review of the literature.  相似文献   

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A time-series study of suicide and homicide rates in Australia and New Zealand from 1950-85 provided limited support for Durkheim's theory of suicide and no support for Henry and Short's theory of the relationship between suicide and homicide. The need for rival theories is discussed.  相似文献   

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Supine abdominal radiographs of 59 patients with documented pneumoperitoneum were evaluated for findings of pneumoperitoneum. The commonly described signs were seen in only 17%. Localized intraperitoneal air in the right upper quadrant was the most frequent finding, seen in 49% of patients. Identification of these collections of air is dependent upon knowledge of the anatomy of the perihepatic spaces.  相似文献   

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The monoterpenes d-limonene and perillyl alcohol (POH) inhibit the growth of mammary tumors. In this investigation we tested whether POH is also effective in reducing liver tumor growth. Diethylnitrosamine was used to induce liver tumors in male Fischer 344 rats. Two weeks after diethylnitrosamine exposure was discontinued, the animals were divided into POH-treated and untreated groups. The mean liver tumor weight for the POH-treated rats after 19 weeks of POH treatment was 10-fold less than that for the untreated animals. POH did not influence tumor cell proliferation but increased the apoptotic index approximately 10-fold. The mRNA levels for the mannose 6-phosphate/insulin-like growth factor II receptor and the transforming growth factor beta type I, II, and III receptors were also significantly increased in the liver tumors from the POH-treated animals when compared to the corresponding receptor mRNA levels in the normal tissue surrounding the tumors and in the tumors of untreated animals. These results demonstrate that POH does not promote the formation of liver tumors, but rather inhibits their growth by enhancing tumor cell loss through apoptosis.  相似文献   

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We report on a familial three way translocation involving chromosomes 3, 6, and 15 identified by prometaphase banding and fluorescence in situ hybridisation (FISH). Two mentally retarded sibs with different phenotypic abnormalities, their phenotypically normal sister and mother, and two fetuses of the phenotypically normal sister were analysed. The terminal regions of chromosomes 3q, 6q, and 15q were involved in a reciprocal translocation, in addition to a paracentric inversion of the derivative chromosome 15. Conventional cytogenetic studies with high resolution GTG banding did not resolve this rearrangement. FISH using whole chromosome paints (WCPs) identified the chromosomal regions involved, except the aberrant region of 3q, which was undetectable with these probes. Investigation of this region with the subtelomeric FISH probe D3S1445/D3S1446 showed a balanced karyotype, 46,XX,t(3;15;6) (q29;q26.1;q26), inv der(15) (q15.1q26.1) in two adult females and one fetus. It was unbalanced in two sibs, showing two different types of unbalanced translocation resulting in partial trisomy 3q in combination with partial monosomy 6q in one patient and partial trisomy 15q with partial monosomy 6q in the other patient and one fetus. These represent apparently new chromosomal phenotypes.  相似文献   

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PURPOSE: Our goal was to analyze patients with pulmonary lobular low attenuation (LLA) on thin section CT with regard to the underlying pulmonary diseases and the dynamic changes occurring in the low attenuation regions during respiration. METHOD: Forty-eight consecutive patients with LLA on thin section CT were analyzed retrospectively. Forty-six patients (95%) had symptoms related to respiratory disease, such as productive cough (n = 25) and hemoptysis (n = 18). Only two patients, one with chronic pulmonary embolism and one with Takayasu arteritis combined with bronchiectasis, had pulmonary vascular disease. Six patients, four with bronchiectasis and two with vascular disease, were studied with dynamic CT during forced vital capacity maneuver. Attenuation values for LLA areas and adjacent lung were measured and time-density curves were plotted. RESULTS: Forty-one (85%) patients had bronchiectasis, typically in other than the regions of the LLA. Areas with proximal bronchiectasis showed low attenuation but without notable lobular distribution. Pulmonary vessels in the LLA areas were smaller than those of adjacent normal lung (n = 45). Of 22 patients who underwent pulmonary function tests, 15 had obstructive pattern of impairment. Respiratory dynamic CT showed expiratory air trapping in LLA areas in all six patients. The mean attenuation values of LLA areas were lower than those of the adjacent normal lung by 67 HU at end-inspiration and by 165 HU at end-expiration (p = 0.002). CONCLUSION: The majority of the patients with LLA shown by thin section CT had bronchiectasis elsewhere in the lung, and evidence of air trapping in the LLA was clearly demonstrated. Bronchiolar obstruction may be the most prevalent cause for the development of LLA.  相似文献   

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BACKGROUND: Telomerase is an RNA-dependent DNA polymerase that extends the ends of chromosomes by synthesizing the 6 oligonucleotide repeat TTAGGG and thus serves as a marker for cellular immortality. Although absent in most adult somatic tissues, telomerase activity is present in stem cells and is reactivated in nearly all primary human malignancies. In this study we sought to determine whether tumors of the adrenal glands contain telomerase activity and whether telomerase activity can be used to differentiate benign and malignant tumors of the adrenal glands. METHODS: Tissue was obtained from 23 specimens at adrenalectomy. Adjacent normal adrenal tissue was obtained for control. All specimens were rapidly frozen and stored at -80 degrees C until assay. Telomerase activity was determined by the telomeric repeat amplification protocol (TRAP). RESULTS: Telomerase activity was present in 5 of 23 (22%) of the adrenal tumors. All 3 malignant tumors were strongly TRAP positive. There was a single cortical adenoma that had very weak telomerase activity. The single TRAP-positive tumor of the adrenal medulla was a ganglioneuroma. CONCLUSIONS: Benign adrenal tumors infrequently contain telomerase activity, whereas telomerase reactivation appears to be common in malignant tumors of the adrenal glands. These data suggest that determination of telomerase activity may offer a novel way to facilitate the differentiation of benign and malignant adrenal tumors.  相似文献   

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PURPOSE: This study evaluates the haemodynamic effects of oxygen inhalation on pulmonary artery pressure and pulmonary vascular resistance in patients with chronic thromboembolic pulmonary hypertension. METHOD: In 47 patients with chronic thromboembolic pulmonary hypertension haemodynamic parameters were measured before and after oxygen inhalation. RESULTS: In moderately severe and severe pulmonary hypertension oxygen inhalation significantly reduced mean pulmonary artery pressure by about 11.1% and 4.6%, respectively. However, pulmonary vascular resistance was not significantly affected. Oxygen saturation improved and heart rate was reduced. Cardiac index decreased in severe pulmonary hypertension. Systemic vascular resistance increased. CONCLUSION: We conclude that oxygen inhalation reduces pulmonary artery pressure and improves oxygen supply in patients with moderately severe and severe chronic thromboembolic pulmonary hypertension.  相似文献   

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PURPOSE: To evaluate the magnetic resonance (MR) imaging findings in collision tumors of the adrenal gland. MATERIALS AND METHODS: MR images obtained in 104 patients with a known primary malignant tumor and an adrenal mass were reviewed to find adrenal glands that contained two contiguous but histologically distinct masses. The findings in such cases were correlated with histopathologic findings. RESULTS: In two (2%) cases, both MR and histopathologic findings showed a mass within the adrenal gland that consisted of contiguous adrenal adenoma and metastasis, which represented a collision tumor. The adenomatous component in each tumor showed a (quantitative) decrease in signal intensity relative to that of the liver (79% and 61%) on opposed-phase images, whereas the metastatic component showed an increase in signal intensity (50% and 15%). Similarly, the adrenal lesion-to-spleen signal intensity ratio on opposed-phase images was lower for the adenomatous component in each (0.39 and 0.43) than for the metastatic component (1.17 and 0.90). CONCLUSION: MR imaging can demonstrate and enable characterization of the separate components of collision tumors within the adrenal gland. These findings can be crucial in planning and guiding subsequent percutaneous needle biopsy and patient care.  相似文献   

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Since its inception, CT scan has had a dominant role in hepatic imaging. Recent advances including helical CT scan and bolus-triggered scan initiation software packages have had a significant impact. Issues regarding volume, rate of administration, and type of intravenous contrast are being distilled. Workstations for three-dimensional data reconstructions are producing images that compete with conventional angiography in certain areas, while angiographically assisted CT scan is being refined in others.  相似文献   

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