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1.
2.
We measured serum thymidine kinase (TK) activity with a radioenzyme assay system employing [I-125]-iododeoxyuridine as the tracer on serial specimens from five bone marrow transplant (BMT) patients before and after transplantation. The serum level of TK activity in the 4 patients with effective BMT treatment ranged from 3.0 to 16.9 U/L (mean, 7.80 U/L) before transplantation and from 27.3 to 236.1 U/L (mean, 82.95 U/L) after the BMT treatment. Mean serum TK activity increased 13.17-fold (range, 1.68 to 29.14-fold). In contrast, the activity in the patient with ineffective BMT treatment was not significantly different during, before, or after BMT treatment. In addition, serum TK activity in BMT patients was well correlated with the change in the number of leukocytes before and after BMT treatment [r = +0.709 (p less than 0.01), y = 0.012 x +0.87]. We conclude that the determination of serum TK activity in BMT patients is very useful in monitoring the course of bone marrow transplantation in the early recovery phase.  相似文献   
3.
Clinical usefulness of the measurement of plasma D-dimer levels   总被引:10,自引:0,他引:10  
To evaluate the clinical usefulness of D-dimer, various effects on the measurement of D-dimer were examined. Although both fibrinolytic and fibrinogenolytic products were detected by the measurement of FDP, only fibrinolytic products were detected by the measurement of D-dimer. In patients with DIC and other thrombo-embolic diseases, plasma D-dimer levels were significantly higher than in normal persons. A significant positive correlation between plasma D-dimer and serum FDP was found in DIC patients. In patients with DIC associated with acute promyelocytic leukemia, which is thought to be an increased fibrinogenolysis state, serum FDP was higher than the plasma D-dimer which suggests that increased fibrinogenolysis affects the result of serum FDP measurement. Plasma D-dimer significantly increased 5 minutes after endoscopic embolization with thrombin in the patients with esophageal varices. However serum FDP increased 30 minutes after the treatment, which suggests that the D-dimer is more useful for rapid detection of coagulo-fibrinolytic change than serum FDP. Plasma D-dimer was significantly higher in patients with cerebral infarction and increased with age. These finding suggest the usefulness of plasma D-dimer measurement for the specific and rapid evaluation of coagulo-fibrinolytic activation and thrombo-embolic state.  相似文献   
4.
Primates are able to track a moving target with their eyes, even when the target is seen against a stationary textured background. In this situation, the tracking eye movement induces motion of the background images on the retina (reafference) that competes with the motion of the target's retinal image, potentially disrupting the tracking of the target. Previous work on humans reported that brief perturbations of the background in the opposite direction to pursuit were much less disruptive than perturbations in the same direction as pursuit. Furthermore, if the background moved together with the pursuit target--so as to effectively eliminate the reafference--then the effects of a subsequent background perturbation showed less dependence on direction. This suggested that the direction selectivity to background perturbations during pursuit against a stationary background was due, at least in part, to the prior motion of the background secondary to the pursuit. We now report similar findings in monkeys, and in addition, have investigated the effect of moving the background while the animal was fixating a stationary target. In this situation, the ocular tracking responses to subsequent brief perturbations of the moving background were weaker when the perturbations were in the same direction as the prior background motion than when in the opposite direction. This suggests that the selective insensitivity to the reafferent visual input associated with pursuit across a stationary background is, at least in part, independent of pursuit per se and attributable to a progressive reduction in the sensitivity to sustained background motion.  相似文献   
5.
Rapid and reliable assessment of hepatic graft viability is important for successful orthotopic liver transplantation (OLTx). OLTx was performed in 11 pairs of pigs via a venovenous bypass. Six of these grafts were transplanted immediately (group A), while the other five were preserved in University of Wisconsin (UW) solution for 24 h and then transplanted (group B). All grafts were flushed with 300 ml of chilled (4°C) Ringer's lactate solution before reperfusion of the graft, when 20 ml of effluent from the graft was collected and the concentrations of ammonia, lactic acid, GOT, and LDH were measured. Four of the six pigs in group A survived longer than 3 days, while the other two pigs died of causes other than graft dysfunction. All five pigs in group B died either of hemoperitoneum or hemodynamic instability due to liver failure. The histology of postperfusion biopsies in group A showed minimal pathological changes, while the grafts in group B revealed moderate to severe ischemic injuries. Ammonia and lactic acid in the effluent of group B were significantly higher than those of group A (1511±216 vs 417±333 g/dl and 114.1±12.2 vs 91.4±12.2 mg/dl, respectively; P<0.05 in both cases). Before reperfusion, the rate of total adenine nucleotides in all of the substances in the graft, which were measured using high performance liquid chromatography (HPLC), inversely correlated with the ammonia levels in the effluent. We conclude that an analysis of the effluent, (i.e. the levels of ammonia and lactic acid), flushed from a hepatic graft before reperfusion could serve as a predictor of hepatic graft viability.  相似文献   
6.
Brain temperature modifies glutamate neurotoxicity in vivo   总被引:5,自引:0,他引:5  
The purpose of this study was to examine the effects of mild hypothermia and hyperthermia on glutamate excitotoxicity. Glutamate-induced cortical lesions were produced in hypothermic (32 degrees C), normothermic (37 degrees C), and hyperthermic (40 degrees C) rats by perfusion of a 0.5 M glutamate solution via a microdialysis probe. The volume of the lesion 7 days after glutamate perfusion was quantified histologically by image analysis. This histological assessment was performed in two experiments; in one, each of the target temperatures was induced before glutamate perfusion, and in the other, each of the target temperatures was induced after stopping the glutamate perfusion. We also examined the effect of temperature on the diffusion of exogenously delivered material in the extracellular space using autoradiography of the perfused glutamate solution containing 14C-labeled sucrose. In the two experiments in which each of the target temperatures was induced before or after glutamate perfusion, the volume of damage was reduced by mild hypothermia and enlarged by mild hyperthermia. The volume of 14C diffusion also increased as brain temperature increased. These results provide evidence that small variations of brain temperature modify glutamate excitotoxicity. The results also suggest that the change in glutamate diffusion in the extracellular space is one mechanism by which mild hypothermia and hyperthermia exert their protective and harmful effects respectively.  相似文献   
7.
8.
We conducted a questionnaire survey about radiation-safety management condition in Japanese nuclear medicine facilities to make materials of proposition for more reasonable management of medical radioactive waste. We distributed a questionnaire to institutions equipped with Nuclear Medicine facilities. Of 1,125 institutions, 642 institutes (52.8%) returned effective answers. The questionnaire covered the following areas: 1) scale of an institution, 2) presence of enforcement of radiotherapy, 3) system of a tank, 4) size and number of each tank, 5) a form of draining-water system, 6) a displacement in a radioactive rays management area, 7) a measurement method of the concentration of medical radioactive waste in draining water system, 8) planned and used quantity of radioisotopes for medical examination and treatment, 9) an average displacement of hospital for one month. In most institutions, a ratio of dose limitation of radioisotope in draining-water system was less than 1.0, defined as an upper limitation in ordinance. In 499 hospitals without facilities of hospitalization for unsealed radioisotope therapy, 473 hospitals reported that sum of ratios of dose limits in a draining-water system was less than 1.0. It was calculated by used dose of radioisotope and monthly displacement from hospital, on the premise that all used radioisotope entered in the general draining-water system. When a drainage including radioactivity from a controlled area join with that from other area before it flows out of a institution, it may be diluted and its radioactive concentration should be less than its upper limitation defined in the rule. Especially, in all institutions with a monthly displacement of more than 25,000 m3, the sum of ratio of the concentration of each radionuclide to the concentration limit dose calculated by used dose of radioisotope, indicated less than 1.0.  相似文献   
9.
OBJECTIVE: To assess the safety and efficacy of anticholinergics in men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) by a systematic review of published reports and a meta-analysis of the reported outcomes. METHODS: We searched Medline, Embase and Cochrane databases (1966-2006), and hand-searched relevant reference lists and conference proceedings, for studies on the use of anticholinergics in men with BPH or bladder outlet obstruction. Eligible studies were assessed for quality and foreign language studies were translated. We collected data on all reported outcomes, conducted meta- analyses on the maximum urinary flow rate (Q(max)), postvoid residual urine volume (PVR) and volume at first contraction, and calculated the acute urinary retention (AUR) rate. We used sensitivity analysis to confirm the findings. RESULTS: We identified five randomized controlled trials (RCTs) and 15 observational studies. Four RCTs incorporating 633 patients were included in the meta-analyses. Anticholinergics did not significantly alter Q(max) (0.1 mL/s, 95% confidence interval, CI, 0.6-0.7). The PVR was increased by 11.6 mL (95% CI 4.5-18.6) although there was no significant difference between AUR rates. The total International Prostate Symptom Scores (IPSS) were not significantly different, but there were improvements for IPSS storage subscores in one RCT. The AUR rate was 0.3% at the 12-week follow-up in 365 men in the RCTs and observational studies. CONCLUSION: Anticholinergic use in men with LUTS suggestive of BPH appears to be safe. Further studies are required to establish efficacy with a suitable precision.  相似文献   
10.
Objective  Coronary artery bypass grafting (CABG) in patients with left ventricular dysfunction has been considered to be a challenging operation. We assessed the early angiographic and long-term clinical and functional outcomes of patients with poor left ventricular function who underwent isolated CABG. Methods  We retrospectively reviewed the records of 78 patients with a poor left ventricular ejection fraction (35% or less) who underwent isolated CABG between January 1991 and November 2006. The mean age of the patients was 66.1 ± 9.4 years, and their mean New York Heart Association functional class was 3.1 ± 0.8. Their mean end-diastolic left ventricular diameter was 57.4 ± 8.1 mm, and their mean grade of mitral regurgitation was 0.7 ± 1.0. Early postoperative angiograms were performed at 32.5 ± 33.5 days after the operation. Interval echocardiographic data were analyzed, and the long-term survival rate was evaluated. Results  The average number of distal anastomoses per patient was 3.2 ± 1.1. The operative mortality rate was 7.7%. Stroke occurred in 1.3% of patients. The overall patency rates for arterial and venous grafts were 100% and 97.2%, respectively. The left ventricular ejection fraction significantly improved from 28.2% ± 5.1% to 34.4% ± 8.4%. Both the end-diastolic and end-systolic left ventricular dimensions significantly decreased from 57.4 ± 8.1 to 55.1 ± 8.8 mm and from 47.4 ± 8.4 to 45.1 ± 9.7 mm, respectively. The actuarial patient survival rate at 10 years was 73.1%. Conclusion  CABG in patients with left ventricular dysfunction was effective, with favorable early graft patency rates. The long-term outcome was also acceptable, with echocardiographic functional recovery.  相似文献   
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