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971.
This study compared the safety and efficacy of fentanyl and meperidine for analgesia in pediatric gastrointestinal endoscopy. In a double-blind, randomized trial, 24 patients (11 males) received either fentanyl (1 microg/kg) or meperidine (1 mg/kg). These analgesics were administered in unmarked syringes by an investigator who did not participate in the procedure or in the evaluation of the patient's sedation. There were 17 Caucasians and 7 African-Americans whose mean age was 10.4 +/- 4.4 years. Thirteen patients received meperidine and 11 received fentanyl. Midazolam was given to all patients as needed to provide sufficient sedation for the procedure. Study subjects underwent EGD (n = 17) or colonoscopy (n = 7). There were no differences as assessed by patient, endoscopist, or assistant for tolerance, discomfort, procedure ease, recovery time, complications, heart rate, blood pressure, or oxygen saturation. We conclude that meperidine and fentanyl are equally effective in providing analgesia for pediatric gastrointestinal endoscopy.  相似文献   
972.
Meal stimulation of cortisol secretion: a protein induced effect   总被引:3,自引:0,他引:3  
Cortisol and ACTH secretion was studied in 52 healthy subjects who were fasted of fed various diets: standard, high fat, high carbohydrate, high protein. Subjects fed high protein diet (4 gm/kg body weight) showed significant increases in cortisol both at 30 and 60 min after the 1200 hr meal and 30 min after the 1600 hr meal. Increases in cortisol, of a smaller magnitude, were also seen after both the 1200 and 1600 hr meals in each of the diets with 1 gm protein/kg body weight (standard, high fat, high carbohydrate). ACTH was significantly increased following the 1200 hr and 1600 hr meals with the high protein diet. We conclude that dietary protein plays an important role in meal stimulated cortisol release.  相似文献   
973.
RATIONALE: Circulating levels of testosterone and gonadotrophins of patients with chronic obstructive pulmonary disease (COPD) have never been compared with those of elderly men with normal pulmonary function. Moreover, the relationship of hypogonadism with quadriceps muscle weakness and exercise intolerance has been studied scarcely in men with COPD. OBJECTIVES: To compare circulating levels of hormones of the pituitary-gonadotrophic axis of men with COPD with those of age-matched control subjects. Moreover, to study the relationship of hypogonadism with quadriceps muscle force, 6-min walking distance, and systemic markers of inflammation in the patients. METHODS AND MEASUREMENTS: Circulating levels of follicle-stimulating hormone, luteinizing hormone, testosterone, and sex hormone-binding globulin were determined, and free testosterone was calculated in 78 patients (FEV1: 44 +/- 17% of the predicted values) and 21 control subjects. Moreover, quadriceps muscle force, 6-min walking distance, number of pack-yr, and systemic inflammation were determined. MAIN RESULTS: Follicle-stimulating hormone and luteinizing hormone were higher in the patients, whereas testosterone was lower (p < or = 0.05). The latter finding was also present in 48 non-steroid-using patients with normal blood gases. Low androgen status was significantly related to quadriceps muscle weakness (r = 0.48) and C-reactive protein (r = -0.39) in the patients, but not to exercise intolerance, the number of pack-yr, or increased circulating levels of interleukin 8 or soluble receptors of tumor necrosis factor alpha. CONCLUSIONS: In contrast to exercise intolerance, quadriceps muscle weakness is related to low circulating levels of testosterone in men with COPD.  相似文献   
974.
Aim: To determine the frequency of anti‐cyclic citrullinated peptide antibody (anti‐CCP) in a group of patients with rheumatoid arthritis and another group with other rheumatic diseases. Patients and methods: Anti‐CCP1 and rheumatoid factor (RF) titres were determined in 320 serum samples; 136 from RA patients, 184 from control patients (165 patients with rheumatic diseases other than RA, and 21 patients with lymphoproliferative diseases). Results: The sensitivity of Anti‐CCP was 62.5% (95% CI: 53–70%) for the diagnosis of RA with a specificity of 89.1% (95% CI: 83–93%). The sensitivity of RF was 85.3% (95% CI: 79–91%). The specificity was 64.7% (95% CI: 57–71%). Conclusions: Anti‐CCP1 has not very high specificity for RA regarding other rheumatic disease. However it is still very helpful for the diagnosis of RA.  相似文献   
975.
Pleural involvement with systemic amyloidosis has been reported rarely in the literature. Diagnosis of this entity by percutaneous needle biopsy of the pleura has been described only in two prior case reports. We describe five patients in whom the diagnosis of pleural amyloidosis was established by Cope needle biopsy during evaluation of pleural effusions of indeterminate cause. Three patients presented with a history suggestive of multiorgan disease and a pleural biopsy performed despite a transudative effusion demonstrated amyloid infiltration of the pleura, obviating the need for other organ biopsies. We conclude that in patients with pleural effusions, if history suggests multiorgan involvement and there is suspicion for amyloidosis, then a closed pleural biopsy with special stains for amyloid should be performed even if the effusions are transudative. This may be the diagnostic procedure of choice in such patients.  相似文献   
976.
BACKGROUND AND AIM OF THE STUDY: Replacement of the aortic root is the treatment of choice for aneurysmal dilatation. Many modifications of the Bentall technique have been described, as have valve-sparing procedures. The study aim was to determine the outcome of a versatile modification of composite replacement that has been adopted over the past 12 years. Separate graft and prosthetic valve components were used to allow freedom of valve choice and the use of an appropriately sized graft for the distal aortic anastomosis. METHODS: Between January 1990 and March 2002, 59 patients (45 males, 14 females; mean age 56 +/- 14 years) underwent aortic root replacement using this technique. Indications for surgery were elective in 35 patients and emergent (usually type A aortic dissection) in 24. The range of valve prostheses used, their size, and the size of aortic graft used in each case was assessed. Durations of ischemia and cardiopulmonary bypass were recorded, as was postoperative blood loss and subsequent patient progress, including valve-related events, perioperative mortality and actuarial survival. RESULTS: A wide range of aortic graft sizes was combined with both mechanical and tissue valves (from 1-7 mm larger in diameter). Median postoperative blood loss was 550 ml (IQR 400-800 ml). Perioperative mortality was 5.1%. There were no valve- or technique-related deaths, and the median actuarial survival was 13.17 years. During a 12-year follow up there were no proximal aortic reoperations. CONCLUSIONS: This technique had favorable perioperative mortality, produced a secure proximal suture line, and allowed the surgeon free choice of both valve type and size of aortic graft. This minimized tension at the distal suture line, and produced good hemostasis, especially in those patients with fragile dissected tissues.  相似文献   
977.
NK cells were characterized by their ability to spontaneously kill certain tumor and virus-infected cells. They constitute first line of defense against invading pathogens and usually become activated in viral infections particularly in early phases. Activated NK cells play a crucial role in the induction and amplification of virus-specific immunity by providing IFN-gamma and "danger signal". The functional activities of NK cells are regulated by a balance between the engagement of their inhibitory and activating receptors. In recent years, the discovery of several MHC and non-MHC binding NK receptors has provided important insights regarding NK cell biology and its role in viral infections. These receptors are increasingly being viewed as important regulators of immune response. Like many other viruses, HIV also seems to activate NK cells. However, several studies have reported compromised NK cell functions in HIV-infected individuals. The virus employs several strategies to counter the host's NK cell response, e.g., a differential downregulation of MHC class I molecules on the surface of infected cells, a dysregulated production of NK cell function-enhancing cytokines, direct inhibitory effects of certain viral proteins on NK cell functions, and changes in the expression of NK cell receptors, etc. The individuals expressing activating NK cell receptors and their cognate MHC ligands have activated NK cells. The development of AIDS is significantly delayed in these individuals after HIV infection. The discovery of NK receptors and their ligands has opened new avenues of developing AIDS vaccine and boosting innate and adaptive antiviral immunity in HIV-infected individuals.  相似文献   
978.
During the latter half of 1989, HIV prevalence in South Australian prisoners was 1.4%. The prevalence of HIV infection across the prison system did not change significantly during 1989 but there was clustering of HIV-infected prisoners in some prisons. Almost half the prisoners from all of the South Australian prisons agreed to participate in our studies, from which we estimate that about 42% of prisoners engage in risk behaviours at least once while incarcerated. Prisoners estimated that 36% of all prisoners inject drugs intravenously at some stage during their stay and that 12% engage in anal intercourse at least once. Interviews with former prisoners who had a history of intravenous drug use revealed that about half had injected themselves while in prison, 60% shared needles and most did not clean shared needles adequately. Most of these prisoners injected themselves once a month or less frequently. The conditions for spread of HIV within the prison system exist but at the current prevalence of infection, transmission can be expected to be infrequent. The opportunity exists now to improve and expand preventive measures.  相似文献   
979.
Residual HIV-infected blood in needles and syringes is a source of HIV infection. Using radiolabelled blood we have stimulated needlestick injuries and sharing of syringes by intravenous drug users and quantified the volumes of blood which could be transferred to recipients in these situations. Up to 0.75 microliters of blood was transferred in needlestick simulations, but there was a large variation. In simulations of needlesharing, seven to ten times more blood was transferred from the index user to the first sharer when 2 ml syringes were used compared with 1 ml syringes. Washing with water was not effective in removing 'infected' blood from a syringe.  相似文献   
980.
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