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101.
Pretreatment of low dose radiation reduces radiation-induced apoptosis in mouse lymphoma (EL4) cells
Induction of an adaptive response to ionizing radiation in mouse lymphoma (EL4) cells was studied by using cell survival fraction
and apoptotic nucleosomal DNA fragmentation as biological end points. Cells in early log phase were pre-exposed to low dose
of γ-rays (0.01 Gy) 4 or 20 hrs prior to high dose γ-ray (4, 8 and 12 Gy for cell survival fraction analysis; 8 Gy for DNA
fragmentation analysis) irradiation. Then cell survival fractions and the extent of DNA fragmentation were measured. Significant
adaptive response, increase in cell survival fraction and decrease in the extent of DNA fragmentation were induced when low
and high dose γ-ray irradiation time interval was 4 hr. Addition of protein or RNA synthesis inhibitor, cycloheximide or 5,6-dichloro-1-β-d-ribofuranosylbenzimidazole
(DRFB), respectively during adaptation period, the period from low dose γ-ray irradiation to high dose γ-ray irradiation,
was able to inhibit the induction of adaptive response, which is the reduction of the extent DNA fragmentation in irradiated
EL4 cells. These data suggest that the induction of adaptive response to ionizing radiation in EL4 cells required both protein
and RNA synthesis. 相似文献
102.
Baek NI Kim JM Park JH Ryu JH Kim DS Lee YH Park JD Kim SI 《Archives of pharmacal research》1997,20(3):280-282
A genuine dammarane-glycoside, named as ginsenoside Rs3, was isolated from the MeOH extracts of Korean red ginseng (Panax ginseng C.A. Meyer) through repeated silica gel column chromatographies and its chemical structure was determined as (20S)-protopanaxadiol 3-O-[6″-O-acetyl-β-D-glucopyranosyl (1→2)-β-D-glucopyranoside on the basis of several spectral and physical evidences including HMBC
and FAB-MS. 相似文献
103.
Mercury concentration was determined in the caps and stalks of nine species of edible mushrooms collected at the area of Wieluńska Upland in district of Czestochowa in 1995-96. The mushroom species examined were such as: yellow-cracking bolete Xerocomus subtomentosus, brown birch scaber stalk Leccinum scabrum, slippery Jack Suillus luteus, larch bolete Suillus grevillei, gray knight-cap Tricholoma terreum, parasol mushroom Macrolepiota procera, horse mushroom Agaricus arvensis, fennel funnel cap Clitocybe odora, fairy-ring mushroom Marasmius oreades and tacky green brittle gills Russula aereuginea. The method of mercury measurement was cold-vapour atomic absorption spectroscopy (CV-AAS) after wet digestion of the samples with concentrated nitric acid in a whole glass system. The parasol mushroom and horse mushroom showed a highest mercury concentrations and contained, respectively, 4500 +/- 1700 and 4400 +/- 2400 ng/g dry wt in caps, and 2800 +/- 1300 and 2800 +/- 2100 ng/g dry wt in stalks. In the case of fennel funnel cap and fairy-ring mushroom the mean total mercury concentrations in caps was above 500 ng/g dry wt, and for other species were between 150 +/- 50 and 500 +/- 230 ng/g dry wt. The stalks of the mushroom species examined in all cases showed lower contamination with mercury than caps. The mean total mercury concentrations noted in caps and stalks of mushrooms examined were usually higher than was reported till now in the same species elsewhere in Poland, while a maximum values found in an individual fruiting bodies are within the range of the concentrations noted in specimens collected from an unpolluted areas. 相似文献
104.
Obesity as psychosomatic disease is a mass phenomenon. The number of obese males (BMI > 30) became doubled in the last ten years. In the etiology of obesity play an important role the reactive obesity. In the background of "yo-yo syndrome" often could be found depression, or other psychotic disorder. The low self-esteem, body dissatisfaction, tension, anxiety disorders is well-known in a slimming diet. Obese subjects (n = 29) who were admitted on their request with a view to losing weight were examined (Hamilton Depressive Scala, Hamilton Anxietas Scala, Eating Attitude Test) Physical Conditioning and internal Medicine Department of National Sports Medicine Institute, Budapest. Among obesities with mild and severe depression as treatment of somatic complications was used fluoxetine, in severe cases and depression with severe anxiety was associated with supportive or cognitive-behavioral treatment. The prevalence of binge eating disorders were at 57% and bulimia nervosa was at 3% in using population (n = 29). Decreasing of anxiety and grade of depression significantly correlated with body mass index (p < 0.023, F = 1.997, p < 0.034, F = 3.131). The treatment of fluoxetine significantly correlated with body mass index (T1: p < 0.023, T2: p < 0.03, T3: p < 0.004). The patients indicated their well being as fluoxetine reduced eating, satiety and lower binges. 相似文献
105.
106.
Barone JE Tucker JB Cecere J Yoon MY Reinhard E Blabey RG Lowenfels AB 《The American surgeon》1999,65(4):356-359
Our objective was to determine the incidence of complications in postoperative patients who were either normothermic or hypothermic. A recent, widely publicized paper concluded that the maintenance of normothermia could reduce the incidence of infectious complications and shorten hospitalization in patients undergoing colorectal surgery. However, some controversy arose regarding the methods of this paper. Patients were deliberately rendered hypothermic, were given more than 3.5 days of prophylactic antibiotics and were transfused significantly more units of blood. We reviewed the charts of 150 consecutive patients who underwent elective partial or subtotal colectomy with primary anastomosis. Among the key items analyzed were intraoperative and postoperative temperature, use of warming devices, duration of surgery, transfusions, interval to oral intake and bowel function, length of stay, complications, infections, and laboratory values. Hypothermia was defined as intraoperative temperature <95.5 degrees F. There were 101 normothermic patients and 49 hypothermic patients. Hypothermic patients had a mean age of 68.7 years versus 66.8 for the normothermic patients (P = 0.472). Comorbidities were similar in both groups. Warming devices were used in >90 per cent of the patients in both groups. The rates of postoperative infections and complications were similar in both groups. Postoperative lengths of stay were also not different. Despite finding that one-third of our patients were hypothermic during elective colon resection, hypothermia had no effect on outcome variables. In contrast to the previous study, the incidence of infectious complications was identical in our patients. Before ascribing postoperative complications and increased resource utilization as adverse effects of hypothermia, further studies are indicated. 相似文献
107.
Pseudolesion in segments II and III of the liver on CT during arterial portography caused by aberrant right gastric venous drainage 总被引:2,自引:0,他引:2
Yoon KH Matsui O Kadoya M Yoshigawa J Gabata T Arai K 《Journal of computer assisted tomography》1999,23(2):306-309
We report three cases of pseudolesions caused by aberrant right gastric venous drainage (AGVD) in segment II/III of the liver as demonstrated on CT during arterial portography (CTAP). On CTAP, the lesions were seen as wedge-shaped perfusion defects, and on hepatic arteriography, AGVD directed to the area with the perfusion defect was visible in all three cases. When a perfusion defect is detected at the edge of segments II/III at CTAP, a pseudolesion caused by AGVD should be suspected. 相似文献
108.
Yoon KH Quickel RR Tatarkiewicz K Ulrich TR Hollister-Lock J Trivedi N Bonner-Weir S Weir GC 《Cell transplantation》1999,8(6):673-689
Neonatal porcine pancreas has considerable capacity for growth and differentiation, making it an attractive potential source of islet tissue for xenotransplantation. Pancreases from 1-3-day-old newborn pigs were digested with collagenase and cultured for 8 days. The resulting cellular aggregates are called porcine neonatal pancreatic cell clusters (NPCCs). The mean yield of NPCCs from a newborn pig was 28,200 +/- 1700 islet equivalents. Cytokeratin 7 (CK7) was used as a marker for the immunostaining of pancreatic duct cells. In neonatal pancreas, 18% of the insulin-positive cells co-stained for CK7, thus being protodifferentiated. NPCCs also contained protodifferentiated cells; insulin/PP and insulin/somatostatin co-stained cells were more common than insulin/glucagon cells. Between 1 and 8 days of culture, the DNA content of the NPCCs fell to 16% and the insulin content to 33% of the starting value, mainly due to the preferential loss of exocrine cells. Transplantation of 2000 or 4000 NPCCs into diabetic nude mice typically normalized glucose values in 10-20 weeks. Mice with successful grafts had lower fasting blood glucose levels than normal mice and accelerated glucose clearance after an i.p. glucose load. The starting NPCCs consisted of 17% insulin-staining cells, but the grafts of mice with reversed diabetes consisted of 94% beta cells, with some co-stained for CK7, indicating that the grafts still contained immature cells. The mass of insulin-producing cells rose from 0.22 +/- 0.08 mg 1 week after transplantation to 4.34 +/- 0.27 mg in mice sacrificed at 27-35 weeks. In summary, NPCCs contain mostly islet precursor cells, which when transplanted into nude mice undergo striking differentiation and beta cell expansion. 相似文献
109.
Mouse-to-rat testicle transplantation 总被引:4,自引:0,他引:4
Lee S Wang Y Kim S Cho C Tarin T Sileshi B Yoon JH Mazzoni G Youngkin T Wolf P Gittes RF 《Microsurgery》1999,19(2):66-70
This report details mouse-to-rat testicular transplantation with immediate revascularization. Donor preparation involved grafting a long segment of aorta and inferior vena cava (IVC) containing the testicular artery and vein. The graft aorta and IVC were anastomosed to the rat aorta and IVC, respectively. Vasovasostomy was completed and the scrotal epithelia were anastomosed to draw the graft toward the host scrotal sac. Twenty-nine of 53 transplants were determined to be viable. Histologically, 6- to 18-hr-old grafts displayed moderate to minimal polymorphonuclear neutrophil (PMN) infiltrates. Ischemia set in somewhere between 18-24 hr postoperatively. Beyond 24 hr the grafts displayed progressive infiltration of PMN and perivascular and intertubular lymphocytes, disorganization of the germinal epithelium, and cessation of spermatogenesis. 相似文献
110.
1. The effect of the alpha2-adrenoceptor agonist, terbutaline, was investigated on simultaneously measured force and intracellular free calcium ([Ca2+]i) in intact rat soleus muscle fibres, and on contractile protein function and Ca2+ content of the sarcoplasmic reticulum (SR) in skinned fibres. 2. Terbutaline (10 microM) had no significant effect on either resting force or [Ca2+]i. Exposure to terbutaline increased both the integral of the indo-1 ratio transient and peak twitch force by 37%. 3. At sub-maximal (10 Hz) stimulation frequencies, terbutaline accelerated force relaxation but had highly variable effects on tetanic force amplitude. The corresponding indo-1 ratio transients were significantly larger, and faster to decay than the controls. 4. Terbutaline increased tetanic force at near maximal stimulation frequencies (50 Hz) by increasing tetanic [Ca2+]i. Force relaxation was accelerated at this frequency with no significant change in the indo-1 ratio transient decay rate. 5. All of terbutaline's effects on force and indo-1 ratio transients in intact fibres were completely blocked and reversed by ICI 118551 (1 microM). 6. Mechanically skinned fibres isolated from intact muscles pre-treated with terbutaline showed no significant changes in SR Ca2+ content, myofilament [Ca2+]i-sensitivity or maximum force generating capacity. 7. The results suggest that terbutaline primarily modulates force by altering the amplitude and decay rate of the [Ca2+]i transient via phosphorylation of both the ryanodine receptor (RR) and the SR pump regulatory protein, phospholamban (PLB). The high variability of responses of slow-twitch muscles to beta2-agonists probably reflects individual differences in basal phosphorylation levels of PLB relative to that of RR. 相似文献