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1.
Synovialsarkome sind mitunter schwierig von anderen Spindelzellsarkomen zu unterscheiden. In diesen Fällen kann der Nachweis einer t(X;18) Translokation unter Verwendung der FISH und RT-PCR helfen. Die vorliegende Arbeit wurde unter der Fragestellung durchgeführt, ob bei Synovialsarkom-verdächtigen Tumoren der simultane Einsatz beider Methoden zum Translokationsnachweis erforderlich ist oder ob eine der Methoden ausreicht.In die Studie wurde Paraffin-eingebettetes Tumorgewebe von 53 Patienten einbezogen, bei denen nach Lichtmikroskopie und Immunhistochemie der Verdacht auf das Vorliegen eines Synovialsarkoms bestand. Es erfolgte der Nachweis von t(X;18) mittels FISH und RT-PCR.  相似文献   
2.
Changes of the age-specific and age-standardized incidence of malignant neoplasms in the GDR between 1962 and 1980 are investigated. A series of cancer localisation has increased in which case improved diagnostics and increased risk are discussed as causes (cancer of colon and rectum, of the pancreas, the breast and the testicle). The epidemics of bronchial cancer has apparently reached its climax, the admission rates stagnate. Cancer of the stomach and recently also cancer of the gallbladder and the extrahepatic bile ducts decrease in their frequency.  相似文献   
3.
Platelets stored in CLX™ blood bags, under normal blood banking conditions, were studied for up to 7 days to determine if changes ocurred in the levels of membrane glycoproteins (GP) Ib-IX and IIb-IIIa. Radiolabeled monoclonal antibodies (MAB) were used to estimate the number of glycoprotein molecules on the surface membrane of intact platelets. GP IX and GP IIb-IIIa levels remained essentially unaltered during storage. In contrast, the content of GP Ib at day 7 decreased by 45% of the total when fresh. The aggregation response to ristocetin, which requires GP Ib, was also diminished after 7 days. Addition of protease inhibitors, leupeptin and/or aprotinin did not appear to influence the degradation of this glycoprotein. We conclude that storage at 22°C has deleterious effects on the GP Ib content of platelets.  相似文献   
4.
As unilateral nephrectomy (UNX) is associated with enhanced mercuric chloride nephrotoxicity, studies were undertaken to characterize the effects of UNX on the tissue content, urinary excretion, and renal cortical subcellular distribution of mercury in the rat. Animals were studied immediately, 2 days or 14 days following UNX, during separate phases of compensatory renal hypertrophy. As compared to sham surgery controls, mercury content in renal cortex was higher in all UNX groups at 24 hr following injection and in the immediate and 2-day groups at 1 or 3 hr. However, UNX was not associated with any alteration in mercury content within outer or inner medulla, liver, plasma, or red blood cells. Subcellular distribution studies demonstrated that cytosolic mercury was uniformly elevated in all UNX groups at 1, 3, and 24 hr following injection while mercury bound to "metallothionein-like" proteins or free in the cytosol was increased only at 1 or 3 hr. Nuclear, mitochondrial, or microsomal mercury content was elevated in the animals studied immediately or 14 days after UNX at 3 or 24 hr following injection, while animals studied 2 days after UNX demonstrated a nearly uniform increase at 1, 3, and 24 hr. Single-kidney urinary mercury excretion was elevated in all UNX groups while excretion per gram kidney weight was increased only in the animals studied immediately or 2 days after surgery. These studies suggest that all phases of compensatory renal hypertrophy are associated with an enhanced content of mercury within the cell cytoplasm and in critical cellular organelles, which may explain the enhanced nephrotoxicity seen following UNX.  相似文献   
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In cats anesthetized with chloralose-urethane, the central respiratory chemoreceptors were exposed to mock CSF of pH 7.02, 7.20, or 7.57. The right carotid body was simultaneously stimulated by intracarotid injections of 40, 80, or 160 μg sodium cyanide in 200 μl Ringer solution. The left carotid nerve and, in some animals, both vagosympathetic truncs were dissected. It could be demonstrated the the increase in ventilation produced by application of NaCN to the peripheral chemoreceptors is significantly larger at high than at low mock CSF pH (i.e. at low than at high central stimulus intensity). In vagotomized cats the responses of VT and gelai to NaCN similarly depend upon CSF pH; they are somewhat larger, though, than in intact animals. These results are discussed as compared with results reported by different authors. Supported by the Deutsche Forschungsgemeinschaft (Be 477)  相似文献   
7.
Summary In 11 adult cats, lightly anesthetized with chloralose-urethane, blood from both common carotid arteries was led into a plastic chamber of 15–20 ml and returned to the carotids at a point 1.5 cm more cranial. By doing so arterial blood was assumed to pool within the chamber and lose itsP CO 2 oscillations which are normally known to exist as a result of the respiratory cycle. In control periods blood bypassed the chamber, thus maintaining respiratoryP CO 2 oscillations. Spontaneous ventilation was measured spirometrically. The animals were breathing pure O2.Results. 1. When the sinus (carotid) nerves were intact or sectioned there was no significant difference in ventilation before or after switching from non-oscillating to oscillatingPa CO 2. 2. When the vertebral arteries were ligated a drop in ventilation occurred after turning to oscillatingPa CO 2 which was followed by a slight rise above control values after 30–50 sec. This phenomenon was independent of sinus nerve integrity. Thus in hyperoxie condition the smallPa CO 2 oscillations known to occur in phase with respiration do not seem to provide a respiratory stimulus to resting ventilation above that generated by the mean level ofPa CO 2. The ventilatory depression after vertebral artery ligation must at this time remain unexplained.  相似文献   
8.
Uptake of persistent environmental chemicals by cultured human cells   总被引:1,自引:0,他引:1  
Uptake of the persistent environmental chemicals 2,2',4,4',5,5'-hexachlorobiphenyl and 1,1,1-trichloro-2,2-di-(4-chlorophenyl)ethane (the insecticide DDT) by Chang liver cells, an established human cell line, has been investigated. Monolayer cells were incubated with culture medium to which the lipophilic model compounds had been added. The time course of uptake of either compound was biphasic, reaching equilibrium after about 5 hr of incubation. The ratio of DDT:hexachlorobiphenyl uptake was dependent on the presence of serum proteins. Increasing concentrations of serum proteins in the culture medium progressively inhibited uptake. Efflux from the cells was not entirely reversible: 10-20% of the chemicals were not released. Uptake was a linear function of the external concentration of the compounds. Absorptive binding to the outer cell plasma membrane could be determined by removing bound chemicals with fetal calf serum ("back exchange"). With this method, temperature-dependent translocation through the cell plasma membrane could directly be demonstrated. The effect of low temperature as well as the influence of metabolic inhibitors point out the contribution of energy-driven uptake pathways. Demonstration of LDL receptor-like binding protein on Chang liver cells facilitated estimation of the role of receptor-mediated uptake. This route of uptake proved to be of minor importance only, as was transport of the protein-bound chemicals via fluid pinocytosis. The results demonstrate that cellular endocytosis of plasma membrane-bound chemicals constitutes a major uptake pathway for lipophilic chemicals.  相似文献   
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10.
PURPOSE: To assess the health status of the Hispanic population of Orange County, Florida. METHODS: The methodology utilized secondary data for 66 ethnically identified indicators in a comparative framework applied for a 5-year period (1997-2001). FINDINGS: Orange County Hispanics are younger with lower per capita income than their Florida peers, less likely to be White, and much more likely to be of Puerto Rican origin. Relative to the Hispanic populations in the selected peer counties and statewide, Orange County Hispanics have higher age-adjusted death rates for a majority of disease categories and conditions, such as breast, lung, and prostate cancers; chronic liver disease and cirrhosis; diabetes mellitus; pneumonia and influenza; stroke; acquired immunodeficiency syndrome; motor vehicle accidents; and infant, neonatal, and child mortality. Orange County Hispanics did better in comparison to Orange non-Hispanics, with lower age-adjusted death rates for major causes of death such as heart disease, cancer, and stroke. However, for many indicators, the 5-year trends for Orange County Hispanics are moving in an unfavorable direction in contrast to the trends for non-Hispanics, which are either stable or improving. CONCLUSION: Comparative assessments of Hispanic populations using secondary data enable the development of a comprehensive health status profile. However, this approach is currently constrained by the limited number of ethnically identified indicators and, especially for Hispanics, problems in the accuracy and consistency of the assignment to racial categories and subsequent reporting.  相似文献   
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