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51.
Second mitochondria-derived activator of caspases (Smac/DIABLO) is released from mitochondria into the cytosol during apoptosis, promoting caspase activation by neutralizing the inhibition of inhibitor of apoptosis proteins (IAPs) on caspases. Alteration of apoptosis is essential for cancer development, and cancer cell death by radiation and chemotherapy is largely dependent upon apoptosis. In this study, archival tissues of 100 carcinomas and 50 sarcomas from various origins were analyzed by immunohistochemistry for the expression of Smac/DIABLO. Smac/DIABLO immunoreactivity was seen in 62 of 100 (62%) carcinomas, including 42 of 60 stomach carcinomas, 7 of 10 colorectal carcinomas, 4 of 10 lung carcinomas, 7 of 10 ovarian carcinomas, and 2 of 10 prostate carcinomas. Smac/DIABLO is expressed in 11 of 50 (22%) sarcomas, including 2 of 8 malignant schwannomas, 5 of 11 rhabdomyosarcomas, 2 of 7 malignant fibrous histiocytomas, 1 of 6 leiomyosarcomas, 0 of 8 angiosarcomas, 0 of 8 liposarcomas, and 1 of 2 Ewing's sarcomas. These data demonstrated that Smac/DIABLO expression levels vary depending on the individual cancer types. Furthermore, the present study showed that many human cancers do not express Smac/DIABLO, and suggest that lack of Smac/DIABLO expression in the cancer cells may inhibit apoptosis, thereby promoting their survival.  相似文献   
52.
This report describes an uncommon case of hypertrophic obstructive cardiomyopathy (HOCM) accompanying infundibular stenosis of the right ventricle treated by alcohol ablation therapy, in a 28-yr-old male patient presenting with dyspnea on exertion. HOCM with infundibular stenosis was detected by echocardiogram and cardiac catheterization and patient has dynamic obstructions of both ventricular outflow tracts. We performed alcohol ablation therapy to improve clinical symptoms and to relieve dynamic obstructions of both ventricular outflow tracts. This is the first case in which HOCM with infundibular stenosis of the right ventricle was treated by alcohol ablation therapy.  相似文献   
53.
The effect of membrane stretch on voltage-activated Ba2+ current (I Ba) was studied in antral circular myocytes of guinea-pig using the whole- cell patch-clamp technique. The changes in cell volume were elicited by superfusing the myocytes with anisosmotic solutions. Hyposmotic superfusate (202 mosmol/l) induced cell swelling and increased peak values of I Ba at 0 mV (from −406.6 ± 45.5 pA to −547.5 ± 65.6 pA, mean ± SEM, n = 8) and hyperosmotic superfusate (350 mosmol/l) induced cell shrinkage and decreased peak values of I Ba at 0 mV (to −269.5 ± 39.1 pA, n = 8). Such changes were reversible and the extent of change was dependent on the osmolarity of superfusate. The values of normalized I Ba at 0 mV were 1.43 ± 0.04, 1.30 ± 0.06, 1.23 ± 0.04, 1.19 ± 0.04, 1 and 0.68 ± 0.06 at 202, 220, 245, 267, 290 and 350 mosmol/l, respectively (n = 8). I Ba was almost completely blocked by nicardipine (5 μM) under hyposmotic conditions. The values of steady-state half-inactivation voltage (−37.7 ± 3.3 and −36.5 ± 2.6 mV, under control and hyposmotic conditions, respectively) or the half-activation voltage (−13.6 ± 2.3 and −13.9 ± 1.9 mV) of I Ba were not significantly changed (P > 0.05, n = 6). Cell membrane capacitance was slightly increased from 50.00 ± 2.86 pF to 50.22 ± 2.82 pF by a hyposmotic superfusate (P < 0.05, n = 6). It is suggested that cell swelling increases voltage-operated L-type calcium channel current and that such a property is related to the response of gastric smooth muscle to mechanical stimuli. Received: 14 November 1995/Received after revision and accepted: 8 January 1996  相似文献   
54.
Sulfonated polyrotaxanes (PRx-SO(3)'s), in which sulfonated alpha-cyclodextrins (alpha-CDs) were threaded onto the poly(ethylene glycol) (PEG) segments in a PEG-b-poly(propylene glycol) (PPG)-b-PEG triblock copolymer (Pluronic) capped with benzyloxycarbonyl (Z)-L-phenylalanine (Z-L-Phe), were prepared as a novel surface-modifying biomaterial. Surface modification of the polyurethane (PU) was carried out by blending the PRx-SO(3)'s with a PU solution, followed by solution casting. The incorporated PRx-SO(3)'s led to the enhanced hydrophilicity by changing the surface properties of the PU matrix. Modified PUs showed the stable entrapment of the PRx-SO(3)'s with little extraction into water and enhanced mechanical properties after exposure to water compared to the PU control. The incorporated PRx-SO(3)'s repelled the proteins and kept them from closely approaching the surface areas, prevented platelet activation by thrombin, and effectively repelled bacteria. These results suggest that both the supramolecular structure of the polyrotaxanes and exposure of the sulfonated groups onto the surfaces contribute to these phenomena. Thus, surface modification with PRx-SO(3)'s is suggested to be useful for the fabrication of biocompatible medical devices.  相似文献   
55.
56.
Heart-lung transplantation in Korea   总被引:1,自引:0,他引:1  
Heart-lung transplantation is an effective treatment for patients with various forms of congenital heart disease or pulmonary hypertension. Since the first heart-lung transplantation in 1997, five transplants have been performed in Korea. Three cases were performed in 1997, one in 1998, and the latest one in 2002. The preoperative diagnoses were complex congenital heart disease (CHD) in 2, and CHD with Eisenmenger's syndrome in 3. In this paper, we report five cases of heart-lung transplantation performed in Korea, and include a review of the relevant literature.  相似文献   
57.
Transjugular intrahepatic portosystemic shunt (TIPSS) is a promising method of treatment for gastric or esophageal variceal bleeding. This study was performed to determine the prognostic factors contributing to the survival of patients after TIPSS for gastric or esophageal variceal bleeding. One hundred and fifty-five patients who underwent TIPSS between September 1991 and March 2001 were followed up by clinical examination, upper gastrointestinal endoscopy, and Duplex sonography. The mean portohepatic pressure gradient prior to TIPSS was 20.5+/-9.93 mmHg and dropped to 10.7+/-6.62 mmHg after TIPSS (p<0.001). The cumulative survival rate was 75.1% at 6 months, 66.6% at 1 yr, 58.4% at 2 yr, and 38.1% at 5 yr. Survival after TIPSS was inversely related to the Child-Pugh classification (p<0.05). The rebleeding rate was 18.3% at 6 months, 21.0% at 1 yr, 32.8% at 2 yr, and 53.1% at 5 yr. The causes of deaths were hepatic failure (53.5%), recurrent variceal bleeding (11.6%), pneumonia (4.6%), sepsis (3.5%), hepatic encephalopathy (2.3%), and unknown (17.4%). Multivariate analysis (Cox proportional hazard model) revealed that the Child-Pugh classification and age were statistically significant independent prognostic factors. In conclusion, TIPSS is an effective method of treatment for variceal bleeding in cases where other treatment modalities including endoscopic therapy are unsuccessful and the most important prognostic factors are preprocedural hepatic reserve (Child-Pugh class) and age.  相似文献   
58.
BACKGROUND: Influenza vaccination is the primary method for preventing influenza and its severe complications. Healthcare workers (HCWs) are one of the priority groups for the influenza vaccination. OBJECTIVES: To determine whether healthy HCWs, who were vaccinated with the same subtype for the two previous years, could be given less priority for influenza immunization under the vaccine shortage. STUDY DESIGN: We measured hemagglutination-inhibition antibody titers from sequential serum samples in 50 pre-immune subjects and 50 age-matched vaccine-naive subjects: immediately prior to the administration of the vaccine, 4-6 weeks, and 6 months after the vaccination. RESULTS: Prevaccination titers were maintained above protective level and high protection rates were observed for all three strains in pre-immune subjects: A/H1N1, A/H3N2, and B strains. As for the sequential changes, the protection rates for all three strains still remained above 70% until 6 months following the vaccination. CONCLUSION: Skipping influenza vaccination for a year could be considered in healthy pre-immune HCWs under the epidemic of the same subtype as two previous years.  相似文献   
59.
An unusual case study of a desmoplastic small round cell tumor presenting as a 3.5-cm, firm, supraclavicular neck mass and diagnosed by fine-needle aspirate biopsy in a 16-yr-old male is reported. Clinical, cytologic, and immunocytochemical findings are described. Histologic, immunohistochemical, and genetic features are discussed. Desmoplastic small round cell tumor should be considered in the differential diagnosis of small round cell tumors of any site; the importance of ancillary studies in arriving at the correct diagnosis is emphasized.  相似文献   
60.
 Using the whole-cell patch clamp technique, the role of actin microfilament in hyposmotic increase of voltage-operated calcium channel current (I Ba) was studied in guinea-pig gastric myocytes. Hyposmotic superfusate (212 mOsm) increased peak I Ba amplitude by 32.7 ± 6.5%; when cytochalasin-D (Cyt-D, 20 μM), an actin cytoskeleton disruptor, was used, an increase of only 9.7 ± 3.1% was seen. I Baresponse to osmotic stress was potentiated (45.1 ± 4.1% increase) by 20 μM phalloidin, an actin microfilament stabilizer. However, colchicine (100 μM), an microtubule cytoskeleton disruptor, had no effect on either I Ba or its response to hyposmotic solution. Phalloidin also induced a rightward shift of the I/V relationship of I Ba, while Cyt-D itself had no effect. These results suggest that actin cytoskeleton may mediate hyposmotic stretch-induced I Ba increase in gastric smooth muscle. Received: 26 March 1997 / Received after revision: 28 May 1997 / Accepted: 3 June 1997  相似文献   
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