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The effects of age on the characteristics of spinal anaesthesia with plain bupivacaine were investigated in 29 adult patients (less than 50 yr : group I), and 37 older patients (greater than or equal to 80 yr : group II). Three millilitres of 0.5% solution (15 mg) were injected at the L3-L4 interspace in the lateral position; the patients were turned supine immediately afterwards. The onset, extent and duration of sensory and motor blockade, the cardiovascular effects and the quality of anaesthesia were evaluated. Anaesthesia was unsatisfactory in one patient in group I and two patients in group II; they required a supplement with intravenous inhalation anaesthesia. These patients were not included in the analysis of the variables studied. The time to maximum spread was significantly shorter in the group I : 7.3 min versus 9.9 min in group II. A higher sensory spinal blockade was obtained in the older age group (T 10.4 versus T 11.2). There were no significant difference between the two groups in the mean time from the injection to recovery from analgesia in the two uppermost segments (121 min versus 107 min). The mean duration of analgesia at the L2 level did not differ significantly (149 min versus 164 min). All the patients had complete motor blockade of lower limbs. Only the Bromage's degrees 2 and 1 were greater in the elderly's group. In the older group, there was a tendency to a greater decrease in systolic arterial pressure from the preanaesthetic values (-20.9% versus -13%). But moderate falls in mean and diastolic arterial pressures were observed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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This study examined associations of performance-monitoring event-related potentials (ERPs) from go/no-go and flanker tasks with one another, and with psychopathy-related traits of disinhibition, meanness, and boldness. A task-dependent relationship was evident between the error-related negativity (ERN) and trait disinhibition, with high-disinhibited participants showing reduced no-go ERN but not flanker ERN. Disinhibition was also inversely related to variants of the P3 and the error positivity (Pe) from these two tasks. A factor analysis of the ERPs revealed two distinct factors, one reflecting shared variance among the P3 and Pe measures from the two tasks, and the other covariance among the N2 and ERN measures. Scores on the P3/Pe factor, but not the N2/ERN factor, were inversely related to disinhibition, and accounted for associations of this trait with variants of the P3 and Pe across tasks. The implication is that high trait disinhibition relates mainly to reductions in brain responses associated with later elaborative stages in the processing of motivationally significant events across different tasks. Importantly, no-go ERN predicted disinhibition scores beyond N2/ERN factor scores, indicating that high disinhibition is not generally related to diminished early preresponse conflict and error processing, but rather to processing impairments in conditions calling for inhibition of prepotent response tendencies.  相似文献   
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Basir GS  Lam TP  O Ws  Chau MT  Ng EH  Ho PC 《Fertility and sterility》2002,78(5):1055-1060
OBJECTIVE: To investigate the blood flow parameters between cycles of the same women to assess whether parameters predicting a successful pregnancy in a stimulation cycle could be used to determine the outcome of subsequent natural cycles. DESIGN: A prospective study. SETTING: Assisted reproduction unit, the University of Hong Kong. PATIENT(S): Fifty-eight IVF cycles and 40 natural cycles were evaluated. INTERVENTION(S): Assessments of the utero-ovarian pulsatility indices (PIs), resistance indices (RIs), and endometrial color signals. RESULT(S): In IVF cycles, the pregnancy rate (27%) was similar to that in frozen-thawed embryo transfer (FET) (28%) cycles. The utero-ovarian PIs and RIs in IVF cycles were significantly lower than those in the natural cycles. There was a significant correlation between the uterine PI in stimulation cycles and that in natural cycles. In IVF cycles, the pregnancy rate declined significantly when the uterine PI was >2.70 and the RI was >0.9. In FET cycles, no decline in pregnancy rate was seen. Conceptional FET cycles showed significantly higher uterine PI, uterine RI, and endometrial color signals compared with conceptional IVF cycles. CONCLUSION(S): Hemodynamic parameters in stimulation cycles are different from those in natural cycles, and the values of various parameters in predicting pregnancy are also different.  相似文献   
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The choice between regional versus general anaesthesia for elderly patients undergoing hip surgery is debated. It is vitally important to see if the type of anaesthetic administered affects per- and postoperative morbidity and mortality. Seventy women more than 75 yr old suitable for spinal anaesthesia were included in this study. They were randomly divided into two groups: in one (n = 35), general anaesthesia was given with sodium thiopentone, fentanyl, enflurane and vecuronium; in the other (n = 35), spinal anaesthesia was performed with 3 ml 0.5% bupivacaine in isobaric solution. During the anaesthetic period, there were no statistically significant differences between both groups in systolic arterial pressure falls or in increases in the heart rate X systolic arterial pressure product. No serious cardiovascular collapse was encountered. Seven patients (20%) receiving general anaesthesia had mental changes against four only (14.2%) in the spinal group. In patients having general anaesthesia, 22.9% developed bronchopneumonia as opposed to 8.6% in the spinal anaesthesia group (p less than 0.05). The mortality rate at three months was rather similar in the two groups. It was concluded that, in order to reduce the incidence of postoperative central dysfunction and bronchopneumonia, spinal anaesthesia should be preferred in geriatric patients for lower limb surgery.  相似文献   
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High-affinity sucrose uptake in the oral pathogen Streptococcus mutans is mediated by the phosphoenolpyruvate-dependent phosphotransferase system. In this report, we provide evidence that a lower-affinity sucrose phosphotransferase system in S. mutans GS-5, previously described by others, is in fact a high-affinity trehalose uptake system that also recognizes sucrose as a substrate.  相似文献   
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Defective DNA mismatch repair in neoplasia is manifested by extra, aberrant bands within multiple microsatellite markers. The replication error (RER) phenotype is present in most colorectal and endometrial carcinomas in patients with the hereditary nonpolyposis colorectal carcinoma syndrome. In addition, a minority of sporadic colorectal and endometrial carcinomas are RER positive. RER in sporadic colorectal carcinomas has been associated with improved prognosis, but its clinical significance in sporadic endometrial cancer has not been characterized. We analyzed DNA extracted from 109 formalin-fixed sporadic endometrial carcinomas for microsatellite instability. The RER-positive phenotype was demonstrated by microsatellite instability in more than one of the eight dinucleotide markers tested. RER was correlated with pathological and clinical parameters as well as with immunohistochemical staining for the p53 gene product and alterations in codon 12 of Ki-ras. Nine percent of the endometrial carcinomas were RER positive, and RER was significantly associated with high grade and adverse outcome. We found no significant correlation of RER with histological subtype, stage, depth of invasion, mutations in the 12th codon of Ki-ras, or p53 immunoreactivity. We conclude that the RER phenotype is present in a minority of sporadic endometrial carcinomas and is associated with high grade and poor prognosis.  相似文献   
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