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991.
Many authors have previously described that several types of human cancer were associated with elevated levels of IgA and IgA-containing immune complexes. We have recently identified and characterized IgA directed against a ‘benzo[a]pyrene-like’ antigen in sera of patients with mammary tumors. Circulating immune complexes from these sera were precipitated and analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A 18–20·kDa protein was found closely associated with high levels of anti-‘benzo[a]pyrene-like’ IgA in sera of patients having a proliferative pathology.  相似文献   
992.
993.
Background: The effects of desflurane on myocardial contraction and relaxation in diseased myocardium have not been completely understood.

Methods: The effects of desflurane (1.8 to 9.4 vol%) in left ventricular papillary muscles of healthy hamsters and those with genetically induced cardiomyopathy (strain BIO 14.6) were investigated in vitro (29 [degree sign]C, pH 7.40, Ca2+ 2.5 mM; stimulation frequency, 3/min) under low (isotony) and high (isometry) load. Data are mean percentages of baseline +/- SD.

Results: Desflurane induced no significant inotropic effect in healthy muscles (maximum unloaded shortening velocity and isometric active force at 9.4 vol%: 97 +/- 9% and 92 +/- 20%, respectively). In contrast, in cardiomyopathic muscles, desflurane induced a moderate negative inotropic effect (maximum unloaded shortening velocity and active force at 9.4 vol%: 84 +/- 19% and 75 +/- 25%, respectively). The negative inotropic effect was more pronounced than that in healthy muscles under low (P < 0.05) but not high load, and even when concentrations were corrected for minimum alveolar concentrations in each strain. Adrenoceptor blockade or pretreatment with reserpine did not modify the inotropic effect of desflurane, suggesting the absence of intramyocardial catecholamine release. However, tyramine also did not induce any significant catecholamine release in hamster myocardium. In both strains, desflurane induced no significant lusitropic effect under low or high load.  相似文献   

994.
Intrathecal Clonidine Combined with Sufentanil for Labor Analgesia   总被引:3,自引:0,他引:3  
Background: Intrathecal sufentanil provides rapid-onset and complete analgesia for the first stage of labor. The dose required to produce this effect can be associated with maternal respiratory depression, hypotension, nausea, or pruritus. Because clonidine potentiates the analgesic effects of opioids without increasing their side effects, the authors wanted to determine the efficacy of low doses of intrathecal clonidine (15 and 30 micro gram) combined with sufentanil.

Methods: Ninety-eight parturient requesting labor analgesia were studied. In a combined spinal-epidural technique, patients were randomly assigned to receive one of the following intrathecal solutions: either 15 micro gram clonidine (n = 10); 30 micro gram clonidine (n = 10); 2.5 micro gram sufentanil (n = 13); 5 micro gram sufentanil (n = 13); 2.5 micro gram sufentanil and 15 micro gram clonidine (n = 13); 2.5 micro gram sufentanil and 30 micro gram clonidine (n = 13); 5 micro gram sufentanil and 15 micro gram clonidine (n = 13); or 5 micro gram sufentanil and 30 micro gram clonidine (n = 13). Visual analog scores for pain, blood pressure, heart rate, sensory levels, incidence of nausea and pruritus, and motor blockade, and maternal and cord blood concentrations of clonidine were recorded.

Results: Patients receiving 30 micro gram intrathecal clonidine with 2.5 or 5 micro gram intrathecal sufentanil had significantly longer-lasting analgesia (145 +/- 36 and 145 +/- 43 min vs. 104 +/- 35 for those receiving 5 micro gram intrathecal sufentanil alone). Clonidine levels were undetectable in maternal serum.  相似文献   

995.
996.
Haemorrhagic nephritis enteritis of geese (HNEG) is a fatal disease of geese aged from 3 to 12 weeks. The causative virus, Goose haemorrhagic polyomavirus (GHPV), is a member of the Polyomaviridae family We examined goslings either spontaneously or experimentally infected with GHPV. Tissues were sampled for histology, GHPV DNA detection and electron microscopy. Clinical signs and gross lesions observed in experimentally infected goslings were largely consistent with those noticed in field cases. Histological examination showed that, in the acute phase of HNEG, GHPV replicates in almost all the tissues with a particular tropism for endothelial and lymphoid cells. Haemorrhagic foci were widespread in many tissues, including brain. Ultrastructural features were largely consistent with other polyomavirus infections, with accumulation of virions in the nucleus. Non-typical, double-membraned organelles were observed in the cytoplasm. GHPV DNA distribution was widespread in tissues of infected birds, from day 5 post-infection. GHPV therefore induces a systemic disease in its host, leading to severe vascular dysfunction and immunosuppressive B-cell depletion.  相似文献   
997.
Background: The value of postoperative cardiac troponin I (cTnI) has been shown to indicate a higher risk of in-hospital death after cardiac surgery. The authors therefore assessed the long-term prognostic value of cTnI in patients undergoing elective coronary artery bypass grafting.

Methods: Consecutive patients (n = 202) were included and divided into two groups according to the postoperative value of cTnI (< or >= 13 ng/ml). In-hospital mortality and nonfatal cardiac events (delayed extubation > 24 h; postoperative requirement of inotropic agent; ventricular and supraventricular arrhythmia; postoperative myocardial infarction) were recorded. Survivors were then followed up over a 2-yr period. Data are median and odds ratio (95% confidence interval).

Results: Of all patients, 174 (86%) had a low cTnI (4.1 ng/ml; range, 1.1-12.6) and 28 (14%) had a high cTnI (23.8 ng/ml; range, 13.4-174.6). In-hospital mortality was not significantly different (4 vs. 2%), whereas long-term mortality (18 vs. 3%, P = 0.006) and mortality from cardiac cause (18 vs. 1%, P < 0.001) was greater in patients with a high cTnI. A high cTnI was a significant factor predicting death (odds ratio, 7.3 [2.0-27.1]) or death from cardiac causes (odds ratio, 37.4 [4.2-334.4]). Nonfatal cardiac events were also more frequent in the hospital (64 vs. 41%, P = 0.02) and within the 2-yr follow-up period (39%vs. 16%, P = 0.03) in patients with high cTnI.  相似文献   

998.
Multitherapy for diabetes   总被引:1,自引:0,他引:1       下载免费PDF全文
  相似文献   
999.
The modified Strecker synthesis of Patel & Worsley was combined with an enzymatic deamidation in the final step, to produce the title compound. The amino acid is a member of the family of the “fat” amino-acids with high lipophilicity and space-filling properties, as estimated by its Hansch hydrophobicity constant and its Charton steric parameter v. It can be used for qualitative and quantitative studies of structure-activity relationships in biologically active peptides. Three of its derivatives suitable for peptide synthesis are also described.  相似文献   
1000.
Objective: To evaluate the effect of Brief Supportive-Expressive Group Psychotherapy as an adjunct to standard medical care in reducing psychological distress, medical symptoms, and health care costs and improving quality of life in women with systemic lupus erythematosus (SLE). Methods: A randomized clinical trial was conducted with 133 SLE female patients from 9 clinics across Canada. Clinical and psychosocial measures were taken at baseline, posttreatment, and 6 and 12 months posttreatment. Outcomes assessed were psychological distress, quality of life, disease activity, health service utilization, and diminished productivity. Results: Intention-to-treat analyses revealed that there were no clinically important group differences on any of the outcome measures. Conclusion: Although both groups improved over time on several measures (e.g., decreases in psychological distress, stress, and emotion-oriented coping), these changes could not be attributed to the psychotherapeutic intervention. Thus, evidence does not support the referral of these patients to this type of intervention. The study was funded by the National Health and Research Development Program Grant 6605-5080-11  相似文献   
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