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51.
G    l Hi  s  nmez 《Fetal and pediatric pathology》2000,19(4):251-259
Several experimental studies have demonstrated that certain steroid hormones can induce differentiation of mouse myeloid leukemic cells to macrophages and granulocytes. We have shown that high-dose methylprednisolone treatment (HDMP, 20-30 mg/kg/day) can induce differentiation of leukemic cells to mature granulocytes in children with different morphological subtypes of acute myeloblastic leukemia (FAB AML M1, M2, M3, M4). In addition, apoptosis can also be induced in vivo and in vitro in AML blast by HDMP treatment. Short-course (3 to 5 days) HDMP treatment increases the hematopoietic CD34- positive progenitor cells in both bone marrow and peripheral blood in children with AML. Acceleration of leukocyte and neutrophil recovery has been obtained by the administration of short-course HDMP in chemotherapy-induced neutropenic children with AML. The addition of HDMP to anti leukemic chemotherapy increased the complete remission rate and prolonged the duration of remission in children with AML and significantly improved the outcome of AML children who presented with extramedullary infiltration. We suggest that the possibility of HDMP-induced differentiation and apoptosis should be evaluated in patients with other malignant diseases.  相似文献   
52.
The contents of Fe, Cu, Zn, Mn, K, Mg, Ca, Na, As and Cd in gutted Baltic herring (Clupea harengus membras), in Baltic herring fillets and in two commercial ready-to-eat products made of these were investigated. The fish was caught in 1996–1998 in the northern Baltic. The commercial products were fried fillets and fish burgers. The effects of industrial processing on the mineral composition were studied by collecting samples at several consecutive stages. In the gutted fish the levels of Mn, Ca and Cd were considerably higher than in the fillet mainly due to the bones. Significant differences were also observed in the contents of Mg, Na, Cu and Zn. In the burger process the bones and skin were removed which caused a decrease in the Zn and Ca levels. Ingredients such as salt, spices and flour as part of the formula increased Na and Mn contents in the ready-to-eat products. In the final products the Na content was about 6 times higher than that of the fresh fish.  相似文献   
53.
Liver is a major target organ of cadmium (Cd) toxicity following acute and chronic exposure. Metallothionein (MT), a low-molecular-weight, cysteine-rich, metal-binding protein has been shown to play an important role in protection against acute Cd-induced liver injury. This study investigates the role of MT in liver injury induced by repeated exposure to Cd. Wild-type and MT-I/II knockout (MT I/II-null) mice were injected sc with a wide range of CdCl(2) doses, 6 times/week, for up to 10 weeks, and their hepatic Cd content, hepatic MT concentration, and liver injury were examined. Repeated administration of CdCl(2) produced acute and nonspecific chronic inflammation in the parenchyma and portal tracts and around central veins. Higher doses produced granulomatous inflammation and proliferating nodules in liver parenchyma. Apoptosis and mitosis occurred concomitantly in liver following repeated Cd exposure, whereas necrosis was mild. As a result, significant elevation of serum enzyme levels was not observed. In wild-type mice, hepatic Cd concentration increased in a dose- and time-dependent manner, reaching 400 microgram/g liver, along with 150-fold increases in hepatic MT concentrations, the latter reaching 1200 microgram/g liver. In contrast, in MT I/II-null mice, hepatic Cd concentrations were about 10 microgram/g liver. Despite the lower accumulation of Cd in livers of MT I/II-null mice, the maximum tolerated dose of Cd was one-eighth lower than that for wild-type mice at 10 weeks, and liver injury was more pronounced in the MT I/II-null mice, as evidenced by increases in liver/body weight ratios and histopathological analyses. In conclusion, these data indicate that (1) nonspecific chronic inflammation, granulomatous inflammation, apoptosis, liver cell regeneration, and presumably, preneoplastic proliferating nodules are major features of liver injury induced by repeated Cd exposure, and (2) intracellular MT is an important protein protecting against this Cd-induced liver injury.  相似文献   
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55.
AimThe diagnosis and management of multiple renal arteries and veins have gained importance with the increasing number of kidney transplantations and improved techniques in interventional radiology and vascular reconstructions. The aim of this study is to define and to detect the rate of multiple renal arteries and veins in our living kidney transplant donors coming from all parts of our country.MethodsAbdominal computed tomography angiogram findings of 878 kidney transplant donors were analyzed. The presence and the distribution of multiple renal arteries and veins in donors coming from 7 geographic regions in Turkey were noted.ResultsThe presence of multiple renal arteries was observed in 34% (48/141) of patients in the Marmara Region, 36.7% (79/215) of patients in the Black Sea Region, 37.2% (64/172) of patients in the Central Anatolia Region and 36.1% (30/83) of patients in the Southeastern Anatolia Region. The highest incidences of multiple renal arteries were observed in the Mediterranean and Aegean regions, affecting 40% (32/80) and 41.9% (26/62) of patients, respectively, while East Anatolia was found to have the lowest incidence, affecting 28% (35/125) of patients. The incidence of multiple renal veins also varied across regions. The highest incidence was observed in the Central Anatolia Region, where 23.3% (40/172) of patients were affected; the lowest was seen in the Aegean Region, where 11.3% (7/62) of patients were affected. In Turkey as a whole, 35.8% (314/878) of patients presented with multiple renal arteries, while the rate of multiple renal veins was found to be 19% (167/878) among our donors.ConclusionsAs 80% of the kidney transplantations performed in Turkey involve living donors, we think it will be useful to have knowledge of not only the presence of multiple renal arteries and veins, but also the distribution of this feature throughout the different regions of the country.  相似文献   
56.
ObjectivesAlthough endoscopic management is considered as the first-line treatment for biliary strictures, it may be challenging in living donor liver transplant recipients due to the complex nature of duct-to-duct reconstruction. In this study we present the use of a pigtail drainage catheter as a biliary stent to treat biliary strictures after a living donor liver transplant.MethodsTwenty-seven patients with biliary strictures were treated with our novel technique. In this technique, a pigtail catheter was trimmed into 3 parts (proximal, middle, and distal portions). A suture string was passed through the distal hole of the middle portion, which was then reversed and used as a stent while the proximal portion was used as a pusher. Following balloon dilation of the stenotic segment, the distal, reversed middle, and proximal portions were loaded over the guidewire. After proper placement of the stent, the retractor suture string, pusher, and guidewire were removed. The stent was removed during the third or fourth month of placement through endoscopic retrograde cholangiopancreatography (ERCP) in all patients.ResultsNo significant complications developed during the procedure or follow-up period. Ten patients required re-stenting by ERCP during the same session. The mean follow-up period was 2 years. Cholestase enzymes and bilirubin levels were within normal limits in all patients during follow-up.ConclusionStents derived from drainage catheter facilitate treatment of biliary strictures in patients not eligible for the retrograde approach. This stent is cheap, easy to implement, can be easily removed by ERCP, and re-stenting can be applicable in retrograde if needed.  相似文献   
57.
The Lot River is known to be contaminated by metals, mainly cadmium and zinc, due to a former Zn ore treatment plant in the watershed of the Riou-Mort, a tributary of the Lot River. Many studies have been performed to characterize contamination, but few have assessed its consequences on the biological responses of organisms along the gradient. We exposed adult and juvenile New Zealand freshwater mudsnails Potamopyrgus antipodarum at several sites along the gradient of metal contamination for 28 days. Biological responses were monitored at different levels: individual (survival, growth and fecundity), tissue and biochemical (energy status and vertebrate-like sex steroid levels) to better understand the toxicity mechanisms involved. Accumulation of Cd and Zn was high during exposure. Most of the biological effects observed could be linked to this contamination and were concentration-dependent. Histological lesions of the digestive gland were observed, with hypertrophy of calcium cells and vacuolization of digestive cells. Such effects are likely to explain the decrease of energy status (triglycerides and proteins), juvenile growth and adult fecundity observed at the most polluted site. However the magnitude of the fall in fecundity cannot be attributed only to these tissular effects, indicating another mode of action of Cd or possible confounding factors. Steroid accumulation in snails indicated only organic pollution. Histopathological effects proved the most sensitive endpoint to metal (Cd and Zn) contamination.  相似文献   
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59.
《Acta oto-laryngologica》2012,132(6):673-678
A previous study on experimental autoimmune labyrinthitis (EAL) consistently demonstrated transient infiltration of lymphocytes only into the inner ear of mice. To clarify the profile of lymphocytes in the initiation of EAL, the present study investigated cell surface antigens, as well as cytokines, from Day 4 to Day 35, using immunohistochemical techniques. Many CD4+ cells mainly infiltrated the endolymphatic sac as early as Day 4 and gradually spread to the rest of the inner ear. Infiltration peaked on Day 12 and persisted in most animals until Day 35, although the number of cells gradually decreased. In contrast, very few CD8+ cells were found to have appeared in the inner ear of all animals on Day 10, and the number of cells rapidly decreased. Many cells positive for IFN- &#110 and IL-2 were identified in the endolymphatic sac on Day 4. These results suggest that helper T1 lymphocytes, rather than cytotoxic T lymphocytes, may play a central role in the initiation of EAL.  相似文献   
60.
目的:观察冠心康颗粒剂对镉染毒大鼠镉蓄积及脏器钙、锌稳态变化的影响,分析中药对镉染毒大鼠的保护作用和可能机制。方法:镉染毒大鼠补锌及中药干预60天,处死后对心、肝和肾中镉、锌、钙含量进行测定;结果:与空白组比较,各染镉组大鼠心、肝、肾中镉浓度均明显升高(P<0.01),模型组伴钙含量升高和锌含量下降(P<0.01);补锌组及冠心康各组与模型组比较,心、肝、肾镉蓄积量明显减少(P<0.01),钙、锌含量变化亦有明显改善(P<0.01)。结论:镉可在体内蓄积并引起钙、锌稳态失调,锌和冠心康颗粒剂可以减少镉蓄积,并拮抗镉对机体锌、钙稳态的干扰。  相似文献   
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