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Antiandrogen withdrawal syndrome (AWS) is a well-established phenomenon in prostate cancer. However, responses to AWS are usually of limited duration, and a complete response (CR) is extremely rare. We present two patients who exhibited a chemical CR for more than 2 years after the discontinuation of steroidal antiandrogen chlormadinone acetate use. Whether patients who respond to antiandrogen withdrawal include a group of patients with a better prognosis remains uncertain. However, considering that the usual survival period of patients with hormone-resistant prostate cancer is approximately 12 months, both of the patients reported here, who are present in excellent physical condition, exhibiting an improved quality of life, and attending their hospital as outpatients, obviously acquired a prolonged survival because of AWS.  相似文献   
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AIM: To evaluate the incidence, nature and prognosis of multiple primary malignancies involving renal cell carcinoma (RCC) in Japan. METHODS: Between 1975 and 1998, 319 patients underwent an operation for RCC at Hokkaido University, Sapporo, Japan. The incidence of other primary malignancies was determined and classified as antecedent, synchronous or subsequent. Follow-up was obtained by thorough chart review or telephone interview, and ranged from 0 to 276 months (median 49.0 months). To analyze the influence of other primary malignancies on prognosis, overall and cause-specific survival rates of the patients with an antecedent or synchronous malignancy were compared to the remaining patients. RESULTS: Of the 319 patients there was at least one other malignancy in 38 patients (12%). Four patients had two other malignancies. The other malignancies were antecedent in 13, synchronous in 19 and subsequent in 10 patients. Twenty-two patients had gastrointestinal cancer. In cases of antecedent or synchronous diagnosis of other primary malignancies, RCC was commonly incidental, small or low-stage. Multivariate analysis using Cox's proportional hazards model showed that, for overall survival, the presence of other antecedent or synchronous malignancies was the second most significant prognostic factor, following the pathological stage of RCC. CONCLUSIONS: In Japanese patients with RCC, the incidence of other primary malignancies was not uncommon and these malignancies contributed to the prognosis of these patients. Therefore, the malignant potential of individual tumors should be paid careful attention in the management of these patients.  相似文献   
5.
Background and Aims:  Increased numbers and enhanced functions of peripheral neutrophils have been observed in obstructive jaundice. However, the effects of obstructive jaundice on the bone marrow, that is neutrophil production and acquisition of neutrophil chemotactic activity, have been poorly understood. In the present study, differentials of bone marrow cells and chemotactic activity of bone marrow neutrophils were evaluated in bile duct-obstructed rats.
Methods:  Male Wistar rats underwent either bile duct obstruction for 10 days or bile duct obstruction for 4 days followed by 6 days' internal biliary drainage. Differentials of peripheral blood and bone marrow cells were sequentially determined. Chemotactic activity of peripheral and bone marrow neutrophils was evaluated with a modified Boyden method using interleukin-8 (recombinant rat Gro-β) as a chemoattractant.
Results:  Numbers of peripheral neutrophils significantly increased after bile duct obstruction. Significant increases in the myeloid/erythroid (M/E) ratio of bone marrow cells were observed after bile duct obstruction. The neutrophil proliferative pool (promyelocytes and myelocytes) increased initially, followed by an increased neutrophil storage pool (metamyelocytes, bands, and segmented neutrophils). The M/E ratio as well as the neutrophil proliferative and storage pools normalized after internal biliary drainage. Chemotactic activity was enhanced in both peripheral and bone marrow neutrophils after bile duct obstruction, and enhanced chemotaxis was alleviated with internal biliary drainage.
Conclusion:  The present results strongly suggest the principal role of the bone marrow in increasing the number of neutrophils and their chemotactic activity during obstructive jaundice.  相似文献   
6.
Interferon (IFN) therapy is of proven efficacy in chronic hepatitis C, but it is not universally effective and is often limited by side effects. Cyclosporine A (CsA) is a potent immunosuppressant widely used in organ transplantation. We conducted a pilot study to determine whether CsA therapy could affect aminotransferase activity and hepatitis C virus RNA levels in patients with chronic hepatitis C. Cyclosporine A was administered to 10 patients (mean age of 59 years; male: female = 9:1) who did not respond to IFN therapy previously and who had elevated serum alanine aminotransferase (ALT) values for at least 6 months. All patients were positive for HCV-RNA by RT-PCR with genotype 1b. Their mean duration of hepatitis was 15 years. Oral CsA was given for 3 months in a dose that was increased at 1 month intervals from 1.5–2.0 to 2.0–3.0 and 3.0–4.0 mg/kg per day. All patients completed the treatment schedule, although two patients developed mild non-symptomatic hypertension. Serum ALT levels gradually decreased in all but one patient. The mean percentage decrease was 59.5% at the end of therapy (from 153 ± 82 to 62 ± 48 IU/L; P < 0.02). The ALT levels fell to the normal range in five patients, although once therapy was discontinued the enzyme levels tended to return to pretreatment levels. Serum aspartate aminotransferase and g-glutamyl transpeptidase levels similarly decreased. The serum HCV-RNA titre, determined by competitive RT-PCR, did not change in any patient throughout the study period. There were no appreciable alterations in other laboratory tests, such as serum creatinine levels and lymphocyte subsets, except for an increase in serum alkaline phosphatase levels. These findings suggest that CsA, even in a relatively low dose, reduces serum aminotransferase levels without serious side effects in patients with chronic-hepatitis C, although an antiviral effect was not noted.  相似文献   
7.
A high-performance liquid chromatographic (HPLC) assay was developed for the determination of trazodone and its metabolite, 1-m-chlorophenylpiperazine (m-CPP), in plasma. The high level of trazodone in plasma was detected by ultraviolet absorbance at 254 nm and the low level of m-CPP in plasma was detected by coulometric electrochemical detection at 840 mV on the series arrangement of two detectors. Pilsicainide as an internal standard for both compounds was monitored by both detectors. Trazodone and m-CPP in plasma were extracted by a rapid and simple procedure based on CN bonded-phase extraction, and C8 reversed-phase HPLC separation. Determination was possible for trazodone in the concentration range 100–2000 ng mL?1 and for m-CPP in the concentration range 5–100 ng mL?1. The recoveries of trazodone and m-CPP added to plasma were 81·0–84·2 and 68·0–73·2%, respectively, with coefficients of variation of less than 7·3 and 8·2%, respectively. The method is applicable to high level monitoring of trazodone and low level monitoring of m-CPP in plasma of healthy volunteers and patients treated with trazodone.  相似文献   
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The metabolic behavior, clearance, and pulmonary effects ofgadolinium (Gd), one of the rare earth elements, were investigatedafter single intratracheal instillation of gadolinium chloride(GdCl3) in male Wistar rats. There was a dose-related increasein Gd content of lung tissue. Gd content in the supernatantof bronchoalveolar lavage fluid (BALF) did not exceed 5 µgGd/ BALF even at a dose of 100 µg Gd/rat. Gd in the lungtissue decreased very slowly with a biological half-life of136 days at a dose of 50 µg Gd/rat. On the other hand,Gd content in the super natant of BALF was not detectable after31 days. These results suggest that intratracheally instilledGd can be retained in epithelial lining fluid only to a limitedextent as soluble forms and is deposited in the lung tissueprobably in insoluble forms which are metabolized very slowly.Calcium (Ca) content in BALF increased more rapidly than othertoxicological indices such as lactate dehydrogenase activity,protein concentration, and inflammatory cell counts. In thelung tissue, levels of Ca in Gd-instilled groups did not differfrom the control value. Although these data suggest that theorigin of Ca may be blood plasma, biological and/or toxicologicalsignificance of increased Ca is not known. The number of neutrophilsreached the maximum at 12 hr after instillation, indicatingthat Gd has the potency to cause acute lung toxicity. Summarizingthe observation, Gd instilled intratracheally into rats wasdeposited in the lung tissue in nonsoluble forms with an extremelylong half-life, while the metal caused a rapid and selectiveinfiltration of serum Ca before acute lung toxicity.  相似文献   
9.
土茯苓二氢黄酮醇类成分研究   总被引:12,自引:3,他引:12  
目的 :研究土茯苓的化学成分。方法 :用硅胶、大孔树脂、ODS柱色谱及HPLC方法进行分离纯化 ,根据理化性质和光谱数据进行结构鉴定。结果 :分离鉴定了 5个二氢黄酮醇苷类化合物 ,分别为落新妇苷 (1) ,新落新妇苷 (2 ) ,异落新妇苷 (3) ,新异落新妇苷 (4 ) ,(2R ,3R) 花旗松素-3′-O-β-D-吡喃葡萄糖苷 (5 )。 结论 :化合物 2 ,4 ,5为首次从该植物中分离得到。  相似文献   
10.
Mesenchymal-epithelial interactions are important in the gastric mucosal repair. However, specific factors responsible for such interactions have not been established. In the present study, keratinocyte growth factor (KGF) significantly stimulated proliferation of gastric epithelial cells dose dependently and synergistically with hepatocyte growth factor (HGF), epidermal growth factor (EGF) and insulin. Restitution of gastric epithelial monolayers was also assessed, using a round wound restitution model. Keratinocyte growth factor facilitated the restitution of gastric epithelial cells significantly but did not have any effects on gastric fibroblasts. Keratinocyte growth factor receptor mRNA was expressed by gastric epithelial cells, indicating that these effects were elicited by the specific receptor mediated pathway. Northern blot analysis revealed the expression of KGF mRNA in gastric fibroblasts but not in gastric epithelial cells, indicating the production of KGF. These results suggest that KGF might be involved in gastric mucosal repair, through mesenchymal-epithelial interaction.  相似文献   
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