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21.
The relative affinity of various mono and difunctional sulfoxides for lithium picrate in toluene was investigated by a competition method utilizing immobilized linear polyethers (glymes). In general, the difunctional sulfoxides were found to bind more strongly than the monofunctional sulfoxides. However, difunctional ligands which would result in eight-membered ring chelated structures bound lithium ion more strongly than those which would result in six-membered ring chelated structures.  相似文献   
22.
The pouch of Douglas (cul-de-sac) represents the caudal extension of the peritoneal cavity. It is the rectovaginal pouch in the female and the rectovesical pouch in the male. The cul-de-sac is in a dependent position when either upright or supine; it is, therefore, a frequent location for seeded lesions. Abnormalities in the cul-de-sac include metastases, abscesses, and endometriosis. These lesions may be detected by multiple modalities, including barium enema, computed tomography, and ultrasound. Examples of numerous cul-de-sac lesions are presented as they appear with different imaging modalities.  相似文献   
23.
Prolonged platelet preservation by transient metabolic suppression   总被引:2,自引:0,他引:2  
BACKGROUND: In this study whether metabolic suppression can be used to preserve platelet (PLT) function during prolonged storage was investigated. STUDY DESIGN AND METHODS: Washed human PLTs were incubated without glucose and with antimycin A to block energy generation. Metabolic suppressed PLTs (MSPs) were stored for 72 hours at different temperatures to find the optimal storage temperature. Controls were incubated with 5 mmol per L glucose and stored at 22 and 4 degrees C. RESULTS: Following metabolic recovery with glucose, MSPs stored at 37, 22, and 4 degrees C showed an increase in basal P-selectin expression (PSE) reaching greater than 40 percent after about 2, 20, and 48 hours; a decrease in thrombin receptor-activating peptide SFLLRN (TRAP)-induced PSE inversely related to the increase in basal PSE; and a decrease in TRAP-induced aggregation reaching less than 30 percent after about 4, 24, and more than 72 hours. When compared with control suspensions, MSPs stored at 4 degrees C better preserved a low basal PSE and in addition showed a better adhesion to surface coated-von Willebrand factor and fibrinogen in a flow chamber. CONCLUSION: Metabolic suppression before storage at 4 degrees C contributes to better preservation of PLT function.  相似文献   
24.
OBJECTIVE: to analyze the clinical features and associated morbidity in a group of patients with vascular dementia (VD). METHODS: we retrospectively evaluated 25 patients with diagnosis of VD, based on the State of California Alzheimers Disease Diagnostic and Treatment Centers (ADDTC) criteria. Clinical and neuroimaging data and laboratory test results were obtained for the characterization of the sample. RESULTS: the mean age was 68.7 +/- 14.6 years (64.0% men), with mean educational level of 5.2 +/- 4.4 years. Sudden onset of symptoms was observed in 48.0% of patients and stepwise deteriorating and fluctuating courses being observed in 4.0% and 16% respectively. Focal neurologic deficits were the first symptom in 48.0%, with focal deficits being observed in 80% on examination. The main morbidity were: hypertension (92.0%); hypercholesterolemia (64.0%); coronary heart disease (40.0%); smoking (40.0%); hypertriglyceridemia (36.0%); diabetes mellitus (32.0%); Chagas' disease (8.0%). CONCLUSIONS: we observed strong association between VD and hypertension and hypercholesterolemia. The observation of two patients presenting Chagas' disease suggests that this endemic condition may be considered a possible regional risk factor.  相似文献   
25.
Although neuroendocrine changes after induction of hypoglycemia, in patients with diabetes and healthy persons, are thoroughly investigated, cognitive adaptation processes are still insufficiently understood. Changes in cognitive functions are mainly investigated by psychometric tests, which represent a summation of different cognitive processes. We aimed at dissecting cognitive adaptation into single components, i.e. stimulus selection, response choice, and reaction speed during a hyperinsulinemic hypoglycemic clamp in patients with type-1 diabetes and matched healthy controls. Using novel neurophysiological analyses, the event-related potentials of early stimulus selection (selection negativity) and response selection (lateralized readiness potential) were studied, in addition to reaction time (RT). A total of 12 diabetic patients and 12 normal volunteers were studied while receiving a hyperinsulinemic hypoglycemic clamp. RTs and the event-related potentials related to stimulus selection and response selection were significantly delayed during hypoglycemia in both groups, whereas early evoked potentials (P100) were unaltered. This suggests that hypoglycemia delays stimulus selection, with the consequence that also central and motor processing are delayed. In addition, patients with diabetes showed an earlier negative shift over the frontal cortex, which, when compared with the controls, reveals better adaptation to hypoglycemia in frontal cortical brain regions. After restoration of euglycemia stimulus selection, response selection and RT returned to baseline level in the type-1 group. In the control group, however, response selection and RTs were still delayed. This suggests that type-1 patients, possibly because of the past occurrence of hypoglycemic events, might be able to better cope with the hypoglycemic state than healthy volunteers who lack such a history. In summary, our data demonstrate, for the first time, that cognitive adaptation processes to an experimental hypoglycemic episode can clearly be dissected into their single components.  相似文献   
26.
The HAM/TSP caused by HTLV-1 infection usually affects patients to disabling states, and sometimes can lead them to paraplegia presenting symptoms of depression and anxiety, impacting on quality of life.ObjectiveThe purpose of this study was to evaluate the frequency of depression and anxiety and its impact on quality of life in HTLV-1-infected TSP/HAM patients.Material and MethodsThis was a cross-sectional study including 67 asymptomatic (control group) and 63 with TSP/HAM subjects. The instruments used were a demographic questionnaire, scales for anxiety and depression diagnosis (BDI and BAI), questionnaire for the assessment of Quality of Life of the World Health Organization (WHOQOL-Brief) and neurological scale to measure the disability level (Osame's Disability Status Scale). All patients had HTLV-I diagnosis by serological and molecular approaches, monitored at Instituto de Infectologia Emílio Ribas from May 2008 to July 2009. Data were analyzed statistically by frequencies, the Mann-Whitney test and the Spearman correlation test. Data among groups were analyzed and correlated with functional and severity aspects.ResultsThe results showed that patients with HAM/TSP compared to asymptomatic carriers had higher rates of depression (p < 0.001) and anxiety (p < 0.001), and impairment on quality of life in the areas of: dissatisfaction with health (p < 0.001), physical (p < 0.001) and the environment (p = 0.003). The main factors that correlated with levels of depression and anxiety and the domains of the WHOQOL-brief were: education, family income and social class.ConclusionA well conducted evaluation and counseling may help in treatment, for a better quality of life of these patients.  相似文献   
27.
Platelets Stored in a New-Generation Container   总被引:2,自引:0,他引:2  
Background and Objectives : In order to preserve platelet concentrates (PCs) with high yields, a new polyolefin platelet storage container (PL 2410, 1.3L, Baxter, La Châtre, France) with increased gas permeability in combination with a larger surface area has been developed. The storage capacity was studied with platelets in plasma and platelets additive solution. Materials and Methods : Platelet concentrate pools (PCs) of different yields suspended in either plasma (PCs-PL; n = 30) or PAS II (PCs-PAS; n = 37) were prepared. For preparation of PCs with a low, intermediate and high number of platelets 3, 5 and 6 buffy coat (BCs) were pooled with different volumes of plasma and 5 and 6 BCs were pooled with different volumes of PAS II, in order to obtain PCs of equal volumes comparable with routine conditions. All PCs were stored on a flatbed shaker at 22±2°C and evaluated on days 1, 2, 5 and 7 by determining platelet and white cell counts, pH (37°C), pO2, pCO2 and swirling score. Results : Platelet yields ranged from 1.5 up to 5.5 × 1011 platelets/U. On day 7 all PCs-PL (n = 4) with platelet yields above 4.5×1011 had a pH value below 6.8 (range 5.91–6.79). While 7 of 8 PCs-PAS units with platelet yields above 4.0×1011/U showed a pH value below 6.8 (range 6.31–6.70). Conclusion : During 7 days of storage in a new 1.3-liter platelet container, the pH was maintained above 6.8 in PCs in plasma with a yield between 1.5-and 4.5×1011/U; when PAS II was used, the maximum platelet yield allowed for comparable pH maintenance was somewhat lower (4.0x1011/U).  相似文献   
28.
29.
We evaluated the effects of 5-fluorouracil (5FU) and leucovorin (LV) on thymidylate synthase (TS) in normal rapidly dividing tissues, which may contribute to toxic side-effects of treatment with 5FU and LV. TS levels were determined in biopsies of human liver and colon mucosa and murine bone marrow, liver and intestinal mucosa at several time points after administration of therapeutic doses of 5FU or LV/5FU. In murine liver, after treatment with 100?mg/kg 5FU, TS inhibition was significantly higher than after LV/5FU administration (P<0.001). A similar trend was observed in human liver tissue. Murine intestinal mucosa had TS levels below the limit of detection after 5FU or LV/5FU treatment. In human colon mucosa samples, administration of 500?mg/m2 5FU resulted in a large extent of TS inhibition but the small number of samples did not allow a time- or 5FU-LV/5FU-related evaluation. TS activity in murine bone marrow cells was strongly inhibited to 10% of the control value during 48?h. LV/5FU administration resulted in a slightly higher inhibition. No human bone marrow was available to measure TS levels. Both in mice and humans the most pronounced TS inhibition occurred in the tissue that was involved in dose-limiting toxicity. Therefore it is very likely that TS inhibition in normal tissues contributes to the toxic side-effects of 5FU treatment.  相似文献   
30.
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