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81.
82.
Archives of Sexual Behavior - Gay, bisexual, and other men who have sex with men (MSM) experience alarming HIV disparities alongside sub-optimal engagement in HIV interventions. Among MSM, stigma...  相似文献   
83.
Selective Attention Effects on the Reflex Blink   总被引:1,自引:0,他引:1  
Past work has shown that facilitation of reflex blinking accompanies cardiac deceleration when the attention of subjects is directed to a reflex-eliciting stimulus. The present studies showed that when warning stimuli directed attention instead to weak (tactile) stimuli presented simultaneously with reflex-eliciting (acoustic) stimuli, cardiac deceleration was still present but reflex magnitude was unchanged or inhibited. However, latency to reflex onset remained facilitated, i.e., latency and magnitude changes were discordant. The findings were interpreted as evidence for two independent processes: a process capable of selectively enhancing or attenuating sensory input and a non-selective process presumably facilitating motor pathways.  相似文献   
84.
Low-dose sufentanil and lidocaine supplementation of general anaesthesia   总被引:1,自引:0,他引:1  
This randomized double-blind study compared the effects of: (1) saline infusion (C); (2) sufentanil alone (1.0 micrograms.kg-1) (S); and (3) low-dose sufentanil (0.5 micrograms.kg-1) in combination with lidocaine (1.5 mg.kg-1) (LS): on the cardiovascular responses to tracheal intubation and on postoperative ventilation as monitored by respiratory inductive plethysmography in day-care surgical procedures of approximately 60 min duration. Thirty healthy, unpremedicated patients were studied. Thiopentone requirements were reduced by 40 and 28 per cent in the S and LS groups respectively compared with control (P less than 0.001). Both treatments suppressed HR and BP responses (P less than 0.005) to intubation. Postoperatively, PaCO2 was elevated (P less than 0.05) in group S. Dose-related respiratory depression was observed. The incidence of postoperative apnoea was significantly higher in both S and LS groups than compared with control (P less than 0.05). However, only patients in group S showed higher apnoea index and mean apnoea duration over the initial 10-20 min after surgery compared with control (P less than 0.005). In addition, group S showed slower respiratory frequency and prolonged expiratory time (P less than 0.005). In conclusion, an induction dose of sufentanil (1 microgram.kg-1) used in balanced anaesthesia of less than 70 min duration was associated with significant respiratory depression, particularly during the initial 10-20 min after surgery, whereas low-dose sufentanil (0.5 micrograms.kg-1) with lidocaine (1.5 mg.kg-1) had minimal postoperative respiratory depression and comparable attenuation of pressor responses to intubation.  相似文献   
85.
Objectives. Bangladeshi children are less frequently referred to a child psychiatric clinic than their British peers. This study aimed to ascertain if teachers observed less psychological symptoms in Bangladeshi than British children.

Method. Teachers completed a Rutter B2 Scale on samples of 113 ‘Bangladeshi’ and 61 British children aged between 5 and 11 years.

Results. Teachers recognised less symptomatology in the Asian children than their British peers. This trend was significant in children under the age of 8, but there was no significant difference in those aged 8–11 years. Only 13% of Bangladeshi children were fully fluent in English.

Conclusions. Two alternate hypotheses are put forward to explain these findings: (a) because more of the younger children could not speak English and communicate freely with their teachers, their symptoms were not noted by teachers; (b) the symptoms of the older children were a response to the pressures both the children and families faced as new immigrants. This study clearly needs to be replicated with a larger sample and also with interviews with both children and parents in order to validate the Rutter B2 questionnaires as an appropriate measure of disturbance in Bangladeshi children. It should be replicated with validated assessments of the children's fluency in English. It is also important to discuss with Bangladeshi parents what support they would like from both the school and from child psychiatric services, to promote their children's psychological health.  相似文献   

86.
The nature of inflammatory lymphocytes recruited to the CNShas been studied in a model of chronic inflammation. Injectionof killed Corynebacterlum parvum into the cortex of the mousebrain produces a circumscribed inflammatory cellular infiltratearound the injection site, and recruited mononuclear inflammatorycells (IC) can be isolated for flow cytometric analysis. Themajority of IC were T cells. In comparison with the predominantnaive population of mesenteric lymph node T cells, IC T cellsexpress much higher levels of CD44, LFA-1 and ICAM-1, and lowerlevels of CD45RB, features commonly associated with memory (previouslyactivated) cells. In addition, in contrast to the L-selectin+6-integrinlow phenotype of naive lymph node T cells, IC T cellslacked L-selectin and were 6-integrin. Mac-1, recentlyproposed as another marker of memory T cell differentation,was not displayed by IC T cells, suggesting that Mac-1 expressionmay be heterogeneous among memory T cell subsets. A subset ofmesenteric lymph node (MLN) T cells, probably representing activatedT cells undergoing the naive to memory transition, but not ofIC T cells, expressed high levels of 6-, ß7- and E-integrin.IC and MLN naive T cells expressed comparable levels of 4-integrin,but IC T cells stain poorly with anti-ß7 mAbs andwith mAb DATK 32, specific for the 4ß7 heterodimericlymphocyte homing receptor for the mucosal addressin MAdCAM-1,suggesting that these inflammatory cells express more 4ß1than 4ß7. Consistent with this, in in vitro adhesionassays, brain IC bound better than MLN cells to the 4ß1integrin ligand VCAM-1 and the LFA-1 ligand ICAM-1 but adheredvery poorly to the 4ß7 ligand MAdCAM-1. These findingsare consistent with and extend previous immunohistological studiesof T cells in murine experimental autoimmune encephalomyelitis,and demonstrate a distinctive phenotype for lymphocytes beingpresent in the chronically inflamed brain.  相似文献   
87.
Rationale: Despite animal studies implicating 3,4-methylenedioxymethamphetamine (MDMA or Ecstasy) in serotonergic neurotoxicity, there is little direct evidence of changes in neural function in humans who use MDMA as a recreational drug. Objective: The present study investigated whether there is a correlation between quantitative EEG variables (spectral power and coherence) and cognitive/mood variables, and level of prior use of MDMA. Methods: Twenty-three recreational MDMA users were studied. Resting EEG was recorded with eyes closed, using a 128-electrode geodesic net system, from which spectral power, peak frequency and coherence levels were calculated. Tests of intelligence (NART), immediate and delayed memory, frontal function (card sort task), and mood (BDI and PANAS scales) were also administered. Pearson correlation analyses were used to examine the relationship between these measures and the subject’s consumption of MDMA during the previous 12-month period. Partial correlation was used to control for the use of other recreational drugs. Results: MDMA use was positively correlated with absolute power in the alpha (8–12 Hz) and beta (12–20 Hz) frequency bands, but not with the delta (1–3 Hz) or theta (4–7 Hz) bands. MDMA use was negatively correlated with EEG coherence, a measure of synchrony between paired cortical locations, in posterior brain sites thought to overly the main visual association pathways of the occipito-parietal region. MDMA use did not correlate significantly with any of the mood/cognitive measures except the card sort task, with which it was weakly negatively correlated. Conclusions: Alpha power has been shown to be inversely related to mental function and has been used as an indirect measure of brain activation in both normal and abnormal states. Reduced coherence levels have been associated with dysfunctional connectivity in the brain in disorders such as dementia, white-matter disease and normal aging. Our results may indicate altered brain function correlated with prior MDMA use, and show that electroencephalography may be a cheap and effective tool for examining neurotoxic effects of MDMA and other drugs. Received: 19 October 1998/Final version: 12 January 1999  相似文献   
88.

Purpose

To study the haemodynamic effects of intrathecal meperidine, administered either alone or mixed with bupivacaïne.

Methods

We studied 42 Chinese patients, aged 59–87 yr, scheduled for transurethral bladder or prostate surgery, randomized into three equals groups, that received either meperidine 0.8 mg · kg?1 meperidine 0.4 mg · kg?1 plus 1.5 ml of 0.5% heavy bupivacaïne or 3 ml of heavy bupivacaïne 0.5%. Non-invasive systolic (SAP) and mean (MAP) arterial pressures, central venous pressure and cardiac index, stroke index and heart rate (HR) measured by the BoMed NCCOM3-R7S bioimpedance device, were recorded over the first 25 min. Systemic vascular resistance index (SVRI) was derived. Onset of sensory and motor block was also measured. Decreases in MAP of 25% were treated with colloid and metaraminol. Results: The onset of block was slower in the meperidine group (P < 0.05). Decreases in SAP, MAP and SVRI (all; P < 0.001) occurred within five minutes in all three groups. The HR was increased in the bupivacaïne group (P = 0.03), but bradycardias treated with atropine occurred in six patients receiving meperidine and four patients receiving the mixture. Six patients receiving meperidine and two patients receiving the mixture required general anaesthesia for inadequate block. The incidence of nausea and vomiting was higher in the patients receiving meperidine (P < 0.05). No other complications were encountered.

Conclusions

Intrathecal meperidine used alone or mixed with bupivacaïne has no intra-operative advantage over heavy bupivacaïne 0.5%.  相似文献   
89.
We reviewed consecutive patients (n = 12) at McLean Hospital from 1990 through 1991 treated with the combination of the atypical antipsychotic agent clozapine and electroconvulsive therapy (ECT). There were no adverse effects. Three patients had a marked clinical improvement, one a moderate response, four a minimal response, two minimal to no response, and two no response. Using daily doses of up to 550 mg clozapine, this combination appears to be safe, and may be useful in some patients with treatment-refractory psychosis.  相似文献   
90.
Summary In this study we retrospectively reviewed results of the first 9 days of treatment with pamidronate at doses of 30 mg (n=13), 45 mg (n=9), and 90 mg (n=13) in an attempt to see what factors influenced the response of serum calcium to pamidronate.The nadir of serum calcium obtained post treatment was correlated with pretreatment levels of nephrogenous cyclic adenosine monophosphate (NcAMP), the renal tubular threshold for phosphate reabsorption (TmPO4), and the renal tubular threshold for calcium reabsorption (TmCa). Using the post treatment serum calcium levels, patients were divided into good and poor responders depending on whether a normal serum calcium was obtained.Pretreatment NcAMP was significantly correlated with the magnitude of the response of serum calcium (r=0.45, P=0.0001). Pretreatment NcAMP was significantly higher in the poor responders (mean±SEM): 65.0±9.4 nmol/liter GF (poor responders) versus 29.6±6.3 (good responders), P=0.004. NcAMP as a predictor of the acute response of serum calcium showed a sensitivity of 93% and a specificity of 72%. Pretreatment TmPO4 was negatively correlated with the serum calcium response post treatment (r=-0.41, P=0.003). However, though TmPO4 tended to be lower in the poor responders, this was not statistically significant [0.65 mmol/liter GF±0.09 (poor responders) versus 0.76 mmol/liter GF±0.06 (good responders)]. As a predictor of the acute response of serum calcium, TmPO4 was less good with a sensitivity of 70% and specificity of 58%. No significant correlation was present between TmCa and the serum calcium response. A significant negative correlation was evident between NcAMP and TmPO4 (r=-0.35, P=0.003), however, no significant correlation was evident between NcAMP and TmCa or TmPO4 and TmCa.These results suggest that in a hypercalcemic patient where evidence exists for the presence in circulation of a factor with PTH-like activity (i.e., NcAMP is elevated or TmPO4 is low) the response of serum calcium to pamidronate is less good. NcAMP would appear to be a useful predictor of the response of serum calcium, whereas TmPO4 is less discriminating.  相似文献   
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