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51.
Ignatius KP CHENG 《Nephrology (Carlton, Vic.)》1997,3(1):109-111
Summary: The involvement of the IgA immune system and complement components in IgA glomerulonephritis (IgAGN) has prompted the use of immunosuppressive drugs in therapy, but none has so far been shown to alter the natural course of the disease. Because most patients with IgAGN present during the chronic phase of their illness, at the time when the initiating immune events may no longer be active, nonimmune therapy which targets the common pathway of progressive renal injury is likely to be more useful. There is increasing evidence that angiotensin-converting enzyme inhibitors (ACEI) reduce proteinuria and renal injury in patients with IgAGN, and this effect may be observed in both normotensive and hypertensive patients. Yet to be determined is whether this effect is specific for ACEI and whatever other effective antihypertensive drugs may achieve a similar result. Fish oil has recently been shown to retard the progression of renal failure in patients with aggressive IgAGN, but a narrow therapeutic window appears to exist for this form of treatment. Antiplatelet agents on their own appear to be ineffective but in combination with anticoagulation (low dose warfarin) have been shown to have an antiproteinuric effect and may preserve renal function in patients with progressive disease. Future directions of non-immune therapy of IgAGN include evaluation of the renoprotective effect of angiotensin II receptor antagonists, free-radical scavengers and antilipid drugs. More work should also be done to identify factors which put the patients at risk of developing progressive disease and which predict therapeutic response, as has been done recently with the identification of the deletion polymorphism of the angiotensin-converting enzyme gene as a marker of progressive disease and therapeutic response to ACEI in patients with IgAGN. 相似文献
52.
S. J. Edmondston Dr K. P. Singer R. E. Day R. I. Price P. D. Breidahl 《Osteoporosis international》1997,7(2):142-148
The estimation of vertebral fracture risk in individuals with suspected osteopenia is commonly based on measurements of lumbar spine bone density. The efficacy of vertebral size and deformity, as assessed by vertebral morphometry, in the prediction of fractures has been less studied. In an ex vivo investigation the regional relationships between vertebral size, vertebral deformity, bone density and compressive strength throughout the thoracolumbar spine were examined. In 16 vertebral columns (T1–L5) the bone mineral content (BMC) and bone mineral density (BMD) of each segment were measured using lateral projection dual-energy X-ray absorptiometry, and the vertebral cancellous density (VCD) and mid-vertebral cross-sectional area (CSA) measured using quantitative computed tomography. Vertebral body heights were determined from mid-sagittal CT scans, and vertical height ratios calculated for each segment. The failure load and failure stress of the isolated vertebral bodies were determined using a material testing device. Separate analyses were performed for the upper (T1–4), middle (T5–8) and lower (T9–12) thoracic, and lumbar (L1–5) segments. In all regions, failure load was strongly correlated with BMD (r=0.82–0.86), moderately correlated with VCD (r=0.60–0.71) and vertebral height (r=0.22–0.49), and poorly correlated with the height ratios (r=0.04–0.33). Failure stress was best predicted by BMD (r=0.73–0.78) and VCD (r=0.70–0.78) but was poorly correlated with all morphometric variables (r=0.01–0.33). The segmental correlations between BMD and VCD ranged fromr=0.49 tor=0.79. For all regions, BMD and VCD were included in the stepwise regression models for predicting failure load and failure stress. Either the mid-vertebral height or CSA were included in all the failure load models, while mid-vertebral height was included in only one of the failure stress models. The results suggest that vertebral deformity and size (as assessed by vertebral morphometry) make only a minor contribution to the prediction of vertebral strength additional to that provided by bone densitometry alone. The consistent regional relationships between variables appear to support the practice of global fracture risk assessment based on lumbar spine densitometry. 相似文献
53.
J S Carey R A Cukingnan L K Singer 《The Journal of thoracic and cardiovascular surgery》1992,103(1):108-115
The effect of increasing age on quality of life, survival, and risk of reoperation was studied in 2479 patients followed up prospectively 2 to 20 years after myocardial revascularization. Quality of life was determined from annual questionnaires, which we used to calculate a health status index from the patient's symptomatic status and subjective response to the operation, which was graded between zero and 1.00 (asymptomatic). Four age groups were studied: age 49 years or less (AG40), 50 to 59 years (AG50), 60 to 69 years (AG60), and 70 years or older (AG70). Associated problems (left ventricular aneurysm, valve disease, acute myocardial infarction) necessitating treatment were present in 17% (61/361) of AG40 patients, 19% (165 of 859) of AG50 patients, 23% (213/927) of AG60 patients, and 31% (102/332) of AG70 patients. The hospital mortality rate was higher in older patients undergoing combined procedures but not in patients undergoing coronary bypass grafts only. Probability of survival and health status indexes were calculated excluding patients with valve disease and cardiogenic shock. Probability of survival was significantly better (p less than 0.001 by the Wilcoxon test) in patients less than age 60 than in those 60 years or older, but in patients with an ejection fraction greater than or equal to 0.40, probability of survival at 12 years was 0.64 (age less than 60) versus 0.62 (age greater than or equal to 60). The actuarial risk of reoperation, calculated as the difference between probability of survival and probability of survival without reoperation, progressively increased in younger patients but not in patients aged 60 years or older. At 15 years, the reoperation rates were 26% (AG40), 14% (AG50), 5% (AG60), and 7% (AG70). Mean health status index for years 1 to 5 was 0.85 in AG40 patients, 0.84 in AG50 patients, 0.89 in AG60 patients, and 0.90 in AG70 patients; for years 6 to 10, 0.81, 0.80, 0.86, and 0.89; and for years 11 to 15, 0.77, 0.78, 0.84, and 0.84, respectively. Thus quality of life after myocardial revascularization is better, improvement lasts longer, and reoperation rate is less in patients aged 60 years or older. 相似文献
54.
55.
Sociodemographic and behavioral characteristics of HIV antibody-positive blood donors. 总被引:1,自引:1,他引:0
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P D Cleary E Singer T F Rogers J Avorn N Van Devanter S Soumerai S Perry J Pindyck 《American journal of public health》1988,78(8):953-957
This paper describes the sociodemographic and behavioral characteristics of 173 blood donors who were confirmed by Western blot tests to have antibodies to human immunodeficiency virus (HIV), the etiologic agent for acquired immunodeficiency syndrome (AIDS). Seropositive donors were predominantly young, unmarried, and male, and major risk factors could be identified for almost all donors. However, more than 20 per cent of the study participants were women, and many participants were not aware that they were at risk of infection. The heterogeneity of the study population, the lack of awareness among many subjects of risk factors and self-exclusion procedures, and the high level of distress among many subjects after notification, emphasize the need for intensive, well-designed education and support programs. 相似文献
56.
57.
Bakamjian introduced the deltopectoral skin flap in 1965, and thereafter it was used extensively for reconstructive surgery of the head and neck. Flap failure rates of 10% to 25% were reported, necessitating the development of alternative methods of reconstruction and eventually relegating the flap to historical references. Since 1991, we have used the deltopectoral flap in 24 patients for reconstruction after head and neck tumor surgery. Simple technical modifications have been used to enhance the reliability of this flap, with no observed failures or even partial flap loss. The deltopectoral flap remains a versatile and reliable tissue source that can be used simultaneously with the pectoralis major myocutaneous flap for a variety of complex head and neck reconstructions. Laryngoscope, 106:1230-1233, 1996 相似文献
58.
A study was carried out to evaluate the andrological parameters in 540 human semen specimens divided into groups according to sperm counts. The parameters were: motility percentage and grade, percentage of viability and of morphologically normal sperm and immature cells. The Duncan multiple range test and the Kruskal-Wallis test with multiple comparison of ranks were used in the statistical analyses. Of particular interest, among other our findings, were the significant differences obtained by comparing the group with sperm counts up to 5 x 10(6) per ml semen and that with counts ranging from 5.1 to 10 x 10(6) per ml semen. This was true for all parameters with the exception of semen volume. Comparison of the oligozoospermic groups (up to 20 x 10(6)/ml) with those having higher sperm counts also showed significant differences. There was a trend towards improvement of the examined parameters with the increase in sperm density, but with a remarkable heterogeneity particularly within the oligozoospermic groups. In all groups motility, viability and morphological normality of sperm showed a positive correlation with each other. "Normal values" of the parameters studied could be derived from scatterplot charts over the entire range of sperm counts and from the statistical evaluation of the grouped material. 相似文献
59.
N. Limberger E. A. Singer K. Starke 《Naunyn-Schmiedeberg's archives of pharmacology》1988,338(1):62-67
Summary Experiments were carried out in rabbit cerebrocortical slices in order to find out whether the attenuation by presynaptic 2-autoreceptors of effects mediated by presynaptic opioid - and adenosine A1-receptors requires activation of the 2-receptors. The slices were preincubated with 3H-noradrenaline and then superfused with medium containing desipramine 1 mol/l. They were stimulated electrically either with single pulses or with trains of 32 pulses at 1 Hz.The overflow of tritium elicited by a single pulse amounted to 0.21% of the tritium content of the tissue. It was Ca2+-dependent and tetrodotoxin-sensitive and not changed by rauwolscine 1 mol/l or yohimbine 0.3 mol/l. Ethylketocyclazocine (EK; 0.1–10 nmol/l) and R-(–)-N6-phenylisopropyladenosine (PIA; 1–1,000 nmol/1) potently inhibited the overflow evoked by a single pulse, and their effects were not changed by yohimbine. — The overflow of tritium elicited by trains of 32 pulses at 1 Hz amounted to 0.92% of the tritium content of the tissue and was increased approximately fourfold by yohimbine 0.3 mol/l. EK and PIA were less potent inhibitors than in the one pulse experiments. Yohimbine greatly enhanced the effects of EK and PIA. The enhancement was even more pronounced when the Ca2+ concentration in the medium was reduced in order to obtain a control tritium overflow similar to that evoked by 32 pulses in the absence of yohimbine.The results demonstrate that there is no 2-adrenergic autoinhibition when noradrenaline release is elicited by a single pulse. Under these conditions, the non-activated presynaptic 2-adrenoceptor does not interfere with presynaptic opioid - and adenosine A1-receptor mechanisms. It is only when the autoreceptor is activated by released noradrenaline that it attenuates neighbouring presynaptic receptor mechanisms, and this attenuation is removed by 2-adrenoceptor antagonists.Send offprint requests to N. Limberger at the above address 相似文献
60.
P. Phillips S. Shafran G. Garber C. Rotstein F. Smaill I. Fong I. Salit M. Miller K. Williams J. M. Conly J. Singer S. Ioannou 《European journal of clinical microbiology & infectious diseases》1997,16(5):337-345
A randomized trial was conducted to compare the efficacy and safety of fluconazole versus that of amphotericin B in the treatment of candidemia in non-neutropenic adults. Enrollment was stratified by disease severity (APACHE II score). Patients were randomized (1:1) to receive amphotericin B 0.6 mg/kg/day (cumulative dose 8 mg/kg) or fluconazole 800 mg intravenous loading dose, then 400 mg daily for four weeks (intravenous for at least 10 days). Patients were monitored for six months. A total of 106 patients were enrolled. A protocol amendment implemented midway through the trial required patients to be removed from the study and treated with amphotericin B if species identification indicated candidemia due toCandida glabrata orCandida krusei. Baseline characteristics were similar for the two groups; 103 patients (fluconazole, 50; amphotericin B, 53) met the major enrollment criteria. The intention-to-treat analysis indicated successful therapy in 50% of fluconazole recipients compared to 58% of the amphotericin B group (p=0.39; one-sided 95% Cl, –8 to 24%). The efficacy analysis included 84 patients (fluconazole, 42; amphotericin B, 42); successful outcomes were observed in 57% and 62% of cases in the fluconazole and amphotericin B groups, respectively (p=0.66: one-sided 95% Cl, –12 to 22%). The mortality at day 14 for the fluconazole group was 26% and for the amphotericin B group 21% (p=0.52; chi-square test) and remained similar throughout the course of follow-up. Drug-related adverse events were more frequent with amphotericin B than with fluconazole and prompted switching of therapy for two (4%) and zero cases, respectively. Fluconazole and amphotericin B were associated with similar clinical response rates and survival in the treatment of candidemia among non-neutropenic patients; however, drug-related adverse events were more frequent with amphotericin B. 相似文献