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991.
One hundred and thirty-four patients with vasoocclusive diseases were retrospectively tested for three kinds of antiphospholipid antibody (aPL). The mean age at onset of the disease in 58 patients with aPL was 43 years old. Seventeen, 11, and 9 patients were positive for the aCL IgA, IgM, and IgG isotypes, respectively. The rates of anti-phospholipid syndrome (APS) in patients with arterial (n=94), venous (n= 31), or both arterial and venous (n=9) occlusion were 45%, 29%, and 78%, respectively.The rates of APS in patients with autoimmune disease (n=13), thromboangiitis obliterans (TAO) (n= 36), arteriosclerosis obliterans (ASO) with lower leg involvement (n=8) or aortic arch syndrome (n=5), Raynaud's syndrome (n=15), aortitis syndrome (n= 13), ischemic heart disease (IHD) with young onset (n =12), and bilateral leg deep venous thrombosis (DVT) (n=10) were 77%, 46%, 13%, 80%, 40%, 62%, 33%, and 70%, respectively. The cumulative patency rate for reconstructive surgery in patients (n=13) with aCL was found to be considerably lower than that in those without aCL (n=13). From these results it was concluded that IgA was the most valuable aCL isotype for the diagnosis of APS and that aPL should be examined in patients with double-vessel occlusion, autoimmune disease, bilateral leg DVT, aortic arch syndrome, TAO, Raynaud's syndrome, or IHD with young onset. Furthermore, prophylaxis for graft failure is more strongly recommended for patients with aCL than for those without it.  相似文献   
992.
Dysfunction of heart valve prostheses—mechanical as well as biological—is a common problem in cardiac surgery. The reasons for the valve failures are still not well understood. Biological valves especially have an unsatisfactory durability; degeneration and calcification very often lead to the failure of the valves. In our opinion, hidden defects present in the valve material prior to implantation of the valves is a plausible explanation for the dysfunction. Hitherto there has been no technique to detect these defects without destructing the specimen. Holographic interferometry proved to be applicable forin vitro evaluation of mechanical heart valve prostheses. In the present paper we describe application of this method to biological valves. Nine porcine bioprostheses and four fresh porcine aortic valves were investigated by means of holographic interferometry. In eight of nine bioprostheses, the results showed irregularities of the leaflet structure which depend on anomalies of the connective tissue of the leaflets of the valves. To make sure that these findings are not due to normal variations of the morphology, the investigations were carried out with fresh and unfixated porcine aortic valves. In the latter, no such anomalies of the structure were detected. The results obtained confirm the above hypothesis on the origin of the later valve dysfunction. Thus, holographic interferometry tests of bioprostheses prior to their implantation prevent the use of potentially dysfunctional valves.Presented at the 35th World Congress, International College of Angiology, Copenhagen, Denmark, July 1993  相似文献   
993.
994.
995.
OBJECTIVE With the development of new long-acting depot preparations of bromocriptine (bromocriptine LAR), we investigated the effectiveness of intramuscular injections of long-acting bromocriptine in patients with prolactin and GH secreting macroadenomas. STUDY DESIGN AND PATIENTS Fourteen patients with PRL secreting (8 patients) and GH secreting (6 patients) macroadenomas were treated with monthly intramuscular Injections of a long-acting and repeatable form of bromocriptine for 3–6 months. A 50-mg monthly dose was administered In the majority of patients with PRL secreting macroadenomas. A 100-mg monthly dose was administered In all patients with GH secreting macroadenomas. MEASUREMENTS Plasma PRL and/or GH levels were measured 6 and 12 hours after the first injection and then on days 1, 2,14 and 28 after each Injection, up to a maximum period of 6 months. Patients were hospitalized for 48 hours after each Injection and were specifically questioned with respect to side-effects. Pituitary imaging with MRI or CT scans was performed In all patients before commencing treatment and was subsequently repeated In 5/8 patients with macroprolactinomas and 5/6 patients with GH secreting macroadenomas after the completion of a 6-month course of treatment. RESULTS In ail patients with macroprolactinomas, serum PRL levels decreased significantly after their first 50-mg injection with nadir levels obtained by 24–48-hours post Injection (12815 ± 8704 vs 1480 ± 1859 mU/l; mean ± SD, P<0.01). At their latest follow-up, on a 50-mg monthly dose, 4 patients developed normoprolactinaemia (PRL levels <360mU/l) while two patients demonstrated a significant reduction In serum PRL levels (70 and 87% of pretreatment values). In two patients, although a substantial decrement of serum PRL levels was achieved 12-24 hours post injection, serum PRL levels Increased to pretreatment values by day 14 post injection. Both patients received a higher (100mg) monthly dose which was partially effective In one patient. In two patients with GH secreting macroadenomas, a sustained decrease of elevated GH levels was observed; in two patients, while a substantial reduction of the elevated serum GH levels was achieved 12–24 hours after the first and subsequent injections, serum GH levels increased to pretreatment values by day 14 post injection; in two patients there was no effect on the elevated serum GH levels. Significant tumour shrinkage (24–50%) was observed In 5/5 patients with PRL secreting macroadenomas assessed at completion of a 6-month course of treatment. Significant tumour shrinkage was also documented In 2/5 acromegalics tested (29 and 46% respectively). CONCLUSION It is concluded that bromocriptine LAR Is an effective treatment in the majority of patients with macroprolactinomas; it is also partially effective in some patients with GH secreting macroadenomas.  相似文献   
996.
The hypothesis that differences in drug effects of risperidone and haloperidol on negative symptoms in schizophrenia are secondary to effects on positive, extrapyramidal, and depressive symptoms was investigated by means of an analysis of the data from the USA-Canada risperidone double-blind randomized clinical trial of 523 chronic schizophrenic patients. Regression analyses in the total sample and within treatment groups confirmed a strong relationship between changes in negative symptoms and the other variables studied (R2=0.50–0.51,p<0.001). Only depressive symptoms did not contribute significantly to these results (p>0.10). Path analysis showed that the greater mean change (p<0.05) of negative symptoms with risperidone compared to haloperidol could not be fully explained by correlations with favourable effects on positive and extrapyramidal symptoms. The relationship between shift in extrapyramidal symptoms and shift in negative symptoms failed to reach statistical significance; however, there was a clear tendency in the expected direction in both treatment groups.  相似文献   
997.
Summary Rats were treated with desipramine 5mg/kg, nomifensine 10mg/kg, zimelidine 25 mg/kg or with 0.9% sodium chloride once a day during the second and third weeks after birth, and brain stem, caudate/putamen and cortical monoamines, and caudate/putamen dopamine D1 (3[H]SCH 23390) and D2 (3[H]spiroperidol) receptor binding were measured when rats were at two months of age. In the brain stem, the concentration of 3-methoxy-4-hydroxy-phenyl glycol was increased in nomifensine rats and the ratio of 5-hydroxyindoleacetic acid to 5-hydroxytryptamine was increased in zimelidine rats. In the caudate/putamen, the concentrations of 3,4-dihydroxyphenylacetic acid and homovanillic acid and the ratio of homovanillic acid to dopamine were increased in desipramine rats; neither3[H]SCH 23390 nor3[H]spiroperidol binding were affected by any of the three monoamine uptake inhibiting antidepressants studied. In the cortex, the ratio of 5-hydroxyindoleacetic acid to 5-hydroxytryptamine was increased in desipramine and zimelidine rats. The findings suggest that desipramine but not nomifensine increases the metabolism of dopamine in the caudate/ putamen and nomifensine but not desipramine increases the metabolism of norepinephrine in the brain stem, and furthermore that the metabolism of serotonin is affected by desipramine as well as by zimelidine. It is possible that also treatment of women with these drugs during late pregnancy causes long-lasting changes in the brain of human fetus.  相似文献   
998.
Cardiovascular disease is common in the developing world where lack of sophisticated diagnostic equipment may make adequate assessment of the disease impossible. Two-dimensional echocardiography has made a major contribution to the practice of cardiology in Transkei by improving diagnostic ability, aiding in the assessment of patients for surgery locally and for referral elsewhere for open-heart surgery, and in monitoring the progress of pericardial disease. It is cost-effective and appropriate technology for the developing world.  相似文献   
999.
Brain abscess in the 1980s   总被引:1,自引:0,他引:1  
Brain abscess was reviewed in 24 patients admitted to University Hospital, Nottingham over a period of 3 years. Chronic ear infection was the most common predisposing factor, but in 11 patients the focus of infection remained unknown. CT scanning, carried out in all patients, was negative in one patient with clinical signs of meningitis. Polymicrobial and anaerobic infections were common. Actinomyces species were isolated in mixed culture from seven patients; in five the abscess was located in the cerebellum. Therapy was most often a combination of surgical drainage and antimicrobial therapy with beta-lactam agents and metronidazole. Evidence suggests that cefotaxime may offer a suitable alternative to chloramphenicol and benzylpenicillin in the treatment of brain abscess.  相似文献   
1000.
Summary It has been suggested that inherited traits play a role in the development of osteoporosis by providing a background for the modulation of gene expression. In this study, we examine the influence of the different alleles of alpha2-HS glycoprotein (AHSG), a protein of the bone matrix, on quantitative estrogens, estrone and estradiol, and bone measures, bone area and density. Estrogens provide a protective effect against fractures in older women and were thus included in the analyses. Isoelectric focusing of AHSG from sera followed by immunoblotting was used to type 163 white post-menopausal women participating in a clinical trial of the effects of walking on bone loss. Plasma hormones were measured by a combination of extraction, column chromatography, and radioimmunoassay; bone measures on the dominant radius were determined with computerized tomography. Analysis of variance was done on estrogen and bone measures after controlling for the effects of age and body mass index. The two major alleles of AHSG result in three phenotypes, designated AHSG 1-1, AHSG 2-1, and AHSG 2-2. The AHSG 1-1 homozygote showed a decreased concentration of estradiol, the AHSG 2-2 homozygote showed an increased concentration, and the AHSG 2-1 heterozygote was intermediate (P=0.001). Estrone demonstrated a similar pattern in residual analysis although it did not reach statistical significance.  相似文献   
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