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141.
This study compares the predictive power of a single measurement of CD8+CD38+, CD8+CD45RO+ or CD8+CD38+CD45RO+ subpopulations in predicting progression to AIDS in a cohort of HIV+ long-term surviving injecting drug users. The results showed that both the total CD8+ percentage, and the CD8+CD38+ and CD8+CD38+CD45RO+ subpopulations of cells all individually predicted progression to AIDS. In combination with CD4, only the CD8+CD38+ subpopulation enhanced the predictive power of the CD4 percentage alone. The CD8+ percentage correlated negatively with the CD4 percentage and the CD8+CD45RO+ subpopulation did not predict disease progression. The proportion of CD8+CD38+ cells identified which patients with a moderate CD4 level were more likely to progress to AIDS, and conversely, which patients with a low CD4 count were likely to remain clinically stable. The results were consistent irrespective of whether time was measured from the date of seroconversion, or from the date of the test. This study is the first to measure these markers in HIV-infected injecting drug users, and in long-term survivors. The results demonstrate the considerable added value of the CD8+CD38+ cell percentage over the CD4 count alone, in predicting HIV clinical progression.  相似文献   
142.
AIMS--To investigate the application in immunohistochemistry of gamma-subunit specific anti-peptide monoclonal antibodies to human neurone specific enolase (NSE); and to determine their reactivity with formalin fixed, wax embedded sections of normal tissue and neuroendocrine tumours. METHODS--Immunohistochemical staining was performed on sections of formalin fixed, wax embedded tissue with two monoclonal antibodies (NSE-P1 and NSE-P2) raised against different synthetic peptides specific for the gamma subunit of human enolase (neurone specific enolase). RESULTS--Both antibodies gave strong immunostaining in normal tissues and cells known to contain NSE. There was no immunoreactivity in tissues containing either the alpha alpha or beta beta isozymes of enolase. The reactivity of the antibodies with a range of neuroendocrine tumours was also studied and both antibodies gave strong immunostaining of tumour cells in the different tumours. CONCLUSIONS--The use of synthetic peptides from defined regions of a molecule as immunogenes provides antibodies of high specificity. These monoclonal antibodies to NSE are ideally suited for immunohistochemical studies and they should be particularly useful in histopathology as they react with epitopes which are resistant to formalin fixation and wax embedding.  相似文献   
143.
The main aim of this study is to evaluate relationships linking social stigma, HIV/AIDS knowledge, and sexual risk among African American (AA) and South African (SA) college students. One major barrier to HIV prevention efforts is the social stigma associated with HIV/AIDS. Based on the Burkholder et al. (1999) findings, persons who engage in greater stigmatization of persons with AIDS (PWA) and gay people are associated with greater sexual behavior risk for HIV/AIDS. The present study attempted to replicate the Burkholder et al. study using African American and South African college students, but the findings were inconsistent with the aforementioned study. AA respondents had higher social stigma of PWA and gays and higher condom self‐efficacy. While SA respondents were less likely to stigmatize PWA and gay persons and had high‐perceived risk of being infected, they reported engaging in high‐risk sexual behavior. The authors discuss the differences that may account for the dissimilar findings.  相似文献   
144.
Sixty healthy mothers undergoing elective cesarean section received at random either midazolam 0.2 mg/kg or thiopental 3.5 mg/kg with succinylcholine 1 mg/kg for rapid sequence intravenous anesthetic induction. Maintenance of anesthesia was identical in all patients: 50:50 N2O in oxygen, halothane 0.5% and pancuronium 0.05 mg/kg. Hemodynamic responses were similar, as were the biochemical status of mothers and infants, and maternal to fetal blood gas/acid base gradients. Correlation between maternal arterial and fetal (umbilical venous/arterial) pH, PCO2 and base excess values were statistically better with midazolam. However, 1-min Apgar minus color (A-C) scores less than 5/8 (representing "severe" neonatal depression) were recorded in five infants after midazolam, three of whom required tracheal intubation, and one whose mother was given thiopental. This difference reached statistical significance (P less than 0.05). It is concluded that midazolam is less suitable than thiopental for anesthetic induction in patients undergoing cesarean section.  相似文献   
145.
Observations during coronary operations are presented that prove that if the ascending aorta is cross-clamped and suction applied to the left side of the heart or to the aortic root for venting purposes, the pressure rapidly drops in the coronary arterial system and a situation is created in which air may enter through the coronary arteriotomy and pass into the aortic root and the left ventricle. Another mechanism to explain the occurrence of some cases of "iatrogenic" air embolism has also been presented: introduction of air into the ascending aorta while cardioplegic solution is being injected through peripherally attached bypass grafts. Air trapped in these grafts or in the coronary artery itself may propagate proximally as well as distally in the coronary arteries and may reach the aortic root even if the left side of the heart is left unvented. These mechanisms may be responsible for heretofore unexplained cases of "iatrogenic" air embolization. We recommend careful purging of air, which may be present, from the left ventricle and aortic root every time before the aortic cross-clamp is removed during coronary operations.  相似文献   
146.
147.
Petit mal epilepsy: a review and integration of recent information   总被引:4,自引:0,他引:4  
Petit mal (absence) epilepsy remains one of the most enigmatic of neurological disorders, and there is no widely accepted theory of its etiology. This review covers some of the current issues concerned with the disorder, including treatment and prognosis, neurochemical research, behavioral and psychophysiological effects of wave-spiked discharges, and EEG studies of seizure control. With respect to treatment, although effective drug therapy (valproic acid, ethosuximide) exists for the "pure" form of absence epilepsy, other forms, in which there is an admixture of grand mal seizures, are less amenable to pharmacotherapy. Moreover, the frequency of fatal hepatic toxicity following valproic acid therapy has been estimated at 1 in 20,000. With respect to prognosis, follow-up studies indicate that many patients do not outgrow the disorder but continue to suffer absence seizures well into adulthood. In recent years, there has been considerable research on the neurochemical basis of absence epilepsy. Current theories, including those that implicate gamma-aminobutyric acid, catecholamines, and "endogenous" epileptogens, are summarized; and requirements for an experimentally induced animal model of absence epilepsy are discussed. The majority of behavioral studies of the disorder have concerned the effects of petit mal-type discharges on sensory and cognitive processes. Some of these studies are reviewed; and recent work bearing on these issues, involving event-related brain potentials, is presented. Our review concludes with a discussion of research aimed at the development of electrophysiologically based approaches to the reduction of seizure frequency in patients with absence epilepsy.  相似文献   
148.
Cognitive impairment. Can it predict the course of hospitalized patients?   总被引:6,自引:0,他引:6  
All patients admitted to three medical services at the New York Hospital during a one-month period were screened with Folstein's Mini-Mental State Examination. The prevalence of cognitive impairment was 19.8% (23 of 116). Cognitively "impaired" patients, ie, those with a Folstein score less than 24, were older, sicker, and less physiologically stable than the cognitively "intact." The in-hospital mortality (17 versus 5%) and morbidity (39 versus 18%) rates were higher for the cognitively "impaired" patients; these differences could be explained by the greater severity of illness, instability, and comorbidity found in these patients. Cognitively "impaired" patients were particularly susceptible to respiratory complications. Cognitively "impaired" patients had longer lengths of hospital stay, spent more time in hospital awaiting placement, and were more likely to be discharged to a nursing home or require home assistance than their cognitively "intact" counterparts. Three-month mortality rates were also higher for the cognitively "impaired" patients (30 versus 15%). These findings suggest that cognitive impairment on admission may be regarded as a marker for patients with poorer prognoses.  相似文献   
149.
Chronic stress is known to influence dietary choices, and stressed families often report poorer diet quality; however, little is known about how family-based stress is linked with dietary patterns that promote inflammation. This study investigated associations between family-based stress and the inflammatory potential of the diet among preschool-aged children and their parents. Parents (n = 212 mothers, n = 146 fathers) and children (n = 130 girls, n = 123 boys; aged 18 months to 5 years) from 241 families participating in the Guelph Family Health Study were included in the analyses. Parents reported levels of parenting distress, depressive symptoms, household chaos, and family functioning. The inflammatory potential of parents’ and children’s diets was quantified using the Dietary Inflammatory Index (DII®), adjusted for total energy intake (i.e., the E-DIITM). E-DII scores were regressed onto family stress using generalized estimating equations to account for shared variance among family clusters. Compared to those in homes with low chaos, parents in chaotic homes had significantly more proinflammatory dietary profiles (β = 0.973; 95% CI: 0.321, 1.624, p = 0.003). Similarly, compared to those in well-functioning families, parents in dysfunctional families had significantly more proinflammatory dietary profiles (β = 0.967; 95% CI: 0.173, 1.761, p = 0.02). No significant associations were found between parents’ E-DII scores and parenting distress or depressive symptoms, nor were any associations found for children’s E-DII scores. Results were not found to differ between males and females. Parents in chaotic or dysfunctional family environments may be at increased risk of chronic disease due to proinflammatory dietary profiles. Children’s dietary inflammatory profiles were not directly associated with family stress; however, indirect connections through family food-related behaviours may exist. Future research should prioritize elucidating these mechanisms.  相似文献   
150.
BackgroundChronic nonsteroidal anti-inflammatory drug (NSAID) use is associated with gastrointestinal bleeding via inhibition of endogenous mucosal protection and platelet aggregation. This study aimed to determine whether extended NSAIDs after joint arthroplasty is associated with increased risk of gastrointestinal bleeding.MethodsThis was a retrospective study examining 28,794 adults who underwent joint arthroplasty by one of 50 surgeons from 2016 to 2018. Episodes of gastrointestinal bleeding within 90 days postoperatively were identified prospectively. Postoperative medications were reported directly by patients with electronic questionnaires. The primary analysis was performed using binary logistic regression.ResultsA total of 74 (0.26%) episodes of gastrointestinal bleeding occurred within 90 days (median 8 days) postoperatively. Of 5086 patients with complete data included in the primary analysis, 59.6% had used NSAIDs with median duration of 2 weeks (interquartile range, 0-6 weeks). Patients with gastrointestinal bleeding were significantly older (71.3 vs 67.0 years), required longer hospitalizations (2.1 vs 1.5 days), and more commonly had a history of peptic ulcers (10.8% vs 0.9%). However, there was no positive association between NSAID use and gastrointestinal bleeding. In fact, the odds of gastrointestinal bleeding were lower in patients taking NSAIDs. Gastrointestinal bleeding was associated with anticoagulants, antiplatelet agents, and, to a lesser extent, aspirin.ConclusionNSAIDs were not associated with gastrointestinal bleeding and may be prescribed safely for a majority of patients after joint arthroplasty. The greatest odds of gastrointestinal bleeding occurred in patients with peptic ulcer disease and those who received antiplatelet and anticoagulation agents. Increasing age and bilateral surgery were also associated with gastrointestinal bleeding.Level of EvidenceLevel III.  相似文献   
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