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11.
Wallin C.-J. B.; Jacobson S. H.; Leksell L. G. 《Nephrology, dialysis, transplantation》1996,11(11):2269-2275
It has been postulated that patients with chronic renal failure,even in the absence of cardiopulmonary symptoms, accumulateinterstitial pulmonary fluid, which is removed by haemodialysis.To test this hypothesis we used the indocyanine green (ICG)-heavywater double indicator dilution method to measure lung water,cardiac output, and central blood volume in relation to haemodialysis.Ten uraemic patients, without cardiopulmonary symptoms, wereinvestigated at the beginning and end, and 2 h after, a regulardialysis session. A group of 18 surgical patients about to undergoelective abdominal surgery served as controls. Despite normalgas exchange, central blood volume, and cardiac output at thestart of dialysis the mean (SD) lung water was significantlyhigher than in the control group [4.8 (0.9) compared with 3.6(0.7) ml/kg, P<0.001]. There was no correlation between weightgain between sessions of dialysis and the magnitude of lungwater at the start of dialysis. Lung water decreased (P <0.001)to the level of the control group in response to dialysis. Therewas no correlation between weight loss and reduction in lungwater induced by dialysis. In conclusion, we have verified thepresence of subclinical pulmonary oedema which was removed bydialysis in a group of patients with established renal failure.The variations in lung water cannot be explained by hydrostaticmechanisms alone. 相似文献
12.
J J Corbett D M Jacobson R C Mauer H S Thompson 《American journal of ophthalmology》1988,105(3):261-265
Blind spot enlargement in papilledema has been attributed to either mechanical disruption of the integrity of the peripapillary percipient elements by the swollen optic disk or to the Stiles-Crawford effect. We investigated the possibility that blind spot enlargement in papilledema is caused, at least in part, by a refractive scotoma due to peripapillary hyperopia. We reduced the enlarged blind spot in a patient with focal peripapillary hyperopia, without papilledema, to near normal size by using progressively stronger plus lenses. Similarly, with the addition of plus sphere, we reduced the size of the blind spot in five of six patients with papilledema, but in none of our normal subjects. 相似文献
13.
Cellular models and tissue equivalent systems for evaluating the structures and significance of age-modified proteins 总被引:1,自引:0,他引:1
R W Gracy K U Yüksel T M Jacobson M L Chapman J C Hevelone G E Wise S D Dimitrijevich 《Gerontology》1991,37(1-3):113-127
The accumulation of modified proteins in aging is well documented in many aging models. For example, the deamidated isoforms of triosephosphate isomerase accumulate in: (a) old erythrocytes, (b) fibroblasts from old donors, (c) fibroblasts aged in vitro, (d) premature-aging syndromes and (e) old cells in the eye lens. However, a fundamental remaining question is: 'Do such modified proteins interfere with cellular function?' It has been difficult to assess this question at the molecular level using whole-organism models and equally frustrating to evaluate the physiological significance of such changes using classical cellular models. Tissue equivalent systems (TES) provide an opportunity for examining the molecular basis and physiological consequences of modified proteins during aging. TES are composed of differentiating and proliferating heterogeneous cell types with symbiotic cell-cell and cell-matrix interactions. They closely resemble, both morphologically and functionally, the tissues from which they were derived. Aging studies utilizing TES can provide information on modifications of protein structures, isozyme patterns, enzymes of the cellular environmental protection system and metabolic parameters which may regulate protein synthesis and degradation. 相似文献
14.
Occurrence of anti-C1q antibodies in IgA nephropathy 总被引:1,自引:0,他引:1
Gunnarsson I; Ronnelid J; Lundberg I; Jacobson S 《Nephrology, dialysis, transplantation》1997,12(11):2263-2268
Background: The pathogenic mechanisms and the antigens
involved in the establishment and progress of IgA nephropathy are unknown.
As antibodies against C1q have been reported to correlate with SLE
nephritis, we analysed the occurrence of these antibodies in IgA
nephropathy in order to investigate the possibility of pathogenetic
similarities in these renal disorders. Methods: The
occurrence of IgA- and IgG anti-C1q antibodies (anti-C1q) were determined
by ELISA in patients with IgA nephropathy (n=36) and SLE nephritis (n=37),
diseases both known to be associated with circulating immune complexes.
Levels of these antibodies were also determined in two other glomerular
diseases, i.e. idiopathic membranous glomerulo-nephritis (n=7) and minimal
change disease (n=2), in which circulating immune complexes are usually not
present, and in 40 healthy controls. Results: IgA
anti-C1q was observed in increased titres in 11/36 of the patients with IgA
nephropathy, in 2/37 of the patients with SLE nephritis (both with
proliferative disease) and in 1/9 of the patients with membranous and
minimal change disease (P<0.001). Increased titres of IgG anti-C1q
were observed in 1/36 of the patients with IgA nephropathy, in 17/37 of the
patients with SLE nephritis and in 0/9 of the patients with membranous and
minimal change disease (P<0.001). There were no correlations between
the levels of anti-C1q antibodies and clinical parameters such as degree of
proteinuria, haematuria, or renal function. Nor was there any correlation
to the concentration of C3a and the terminal complement complex (TCC) in
patients with IgA nephropathy. Conclusions: The
occurrence of anti-C1q antibodies in both IgA nephropathy and SLE
nephritis, albeit of different predominating isotypes, indicates the
possibility of a similar pathogenic mechanism involved in these renal
disorders. The occurrence of IgA anti-C1q antibodies in patients with IgA
nephropathy has to our knowledge not previously been reported. 相似文献
15.
John W. Jacobson 《Journal of developmental and physical disabilities》1992,4(2):99-113
Controversy about the use of restrictive behavioral procedures persists within the field of developmental disabilities. Many advocates and proponents of the use of exclusively nonrestrictive behavioral procedures have argued that restrictive procedures pose unacceptably high risks of adverse side effects and harm to the people who are treated with them. Yet, little is known about the extent to which procedures like timeout, manual restraint, and overcorrection are actually used in the treatment of people with developmental disabilities who manifest severe behavior disorders. In this article, data gathered on a national sample of people with developmental disabilities age 45 years and older are reviewed to ascertain the extent to which several restrictive procedures are being used in treatment. Findings indicate that these procedures are not being used in an indiscriminate manner. 相似文献
16.
Kimberly M Miller Michael S Okun Hubert F Fernandez Charles E Jacobson Ramon L Rodriguez Dawn Bowers 《Movement disorders》2007,22(5):666-672
Depression is common in Parkinson's disease (PD) and affects 30 to 50% of all patients. In contrast to the wealth of research on depression in PD, little is known about the occurrence of depression in other movement disorders. The primary objective of the current study was to determine whether the high prevalence of depression symptoms seen in PD is also found in other movement disorders, by directly comparing rates of specific depression symptoms and depression severity across PD, dystonia, and essential tremor (ET). Three hundred and fifty-four patients with PD, 83 patients with dystonia, and 53 patients with ET completed the Beck Depression Inventory (BDI). We found no significant between-groups differences for depression severity, frequency, or endorsement of specific depression symptoms. Forty-eight percent of PD patients, 37.3% of dystonia patients, and 34% of ET patients were found to be at least mildly depressed (BDI score of 10 or higher). The most commonly endorsed symptoms were fatigability, difficulty with work, anhedonia, and sleep disturbance. Clinicians should be aware that depression is a frequent problem in dystonia and ET, in addition to PD, and inquire about depression symptoms in these patients so that they can be appropriately treated. 相似文献
17.
The role of renal alpha 2-adrenoceptors in the regulation of glomerular filtration and renal perfusion is unknown. We studied the effects of alpha 2-adrenergic blockade on renal hemodynamics in six patients with insulin-dependent diabetes mellitus (IDDM) and in six healthy subjects. At the basal state, glomerular filtration rate (GFR) was higher in IDDM although the difference from control levels was not statistically significant. Volume expansion, achieved by infusion of isotonic sodium chloride solution, during placebo infusion induced a significant drop in GFR in healthy subjects but not in IDDM patients. Infusion of the alpha 2-adrenoceptor antagonist idazoxan did not further modify the effect of volume expansion on GFR. Renal plasma and blood flow as well as filtration fraction were not significantly changed by volume expansion or idazoxan infusion. Plasma renin activity and plasma aldosterone levels decreased during volume expansion in both IDDM and control subjects. In conclusion, volume expansion induced decreased GFR in healthy controls but not in IDDM patients. Since infusion of idazoxan did not affect GFR or other parameters of renal hemodynamics, renal alpha 2-adrenoceptors do not seem to be involved in the regulation of renal function. Hence, enhanced renal alpha 2-adrenoceptor activity is not likely to underlie hyperfiltration as seen in IDDM. 相似文献
18.
A survey was conducted to ascertain the risk of tuberculosis (TB) among migrant farm workers on the Delmarva peninsula. Relevant histories were obtained from 842 migrants; a total of 709 skin tests were completed, and 239 sputum specimens were examined for acid-fast bacilli (AFB) and culture. No cases of infectious tuberculosis were ascertained by history or AFB examination. One sputum culture was positive for M. tuberculosis and 13 were positive for various species of nontuberculous mycobacteria. Thirty-seven per cent of migrants tested had significant skin test reactions of 10 mm or more. Reaction rates for men were 41 per cent and for women 25 per cent. Age specific rates ranged from 14 per cent in children aged 5-14 to 54 per cent for ages 45-54. Rates for the principal national/ethnic groups were Haitians 55 per cent, Mexicans 36 per cent, US Blacks 29 per cent and US-born Latinos 20 per cent. Based on these results and other information currently available, it is recommended that current Centers for Disease Control (CDC) recommendations for TB prophylaxis continue to be applied for migrant workers, but that mass screening by skin testing in camp populations not be emphasized. Other recommendations focus on: case finding of active disease, improving continuity and follow-up, increasing coordination among involved agencies, and actively supporting improved economic and living conditions for migrant farm workers. 相似文献
19.
John J Doyle Alfred I Neugut Judith S Jacobson Victor R Grann Dawn L Hershman 《Journal of clinical oncology》2005,23(34):8597-8605
PURPOSE: Adjuvant chemotherapy, especially with anthracyclines, is known to cause acute and chronic cardiotoxicity in breast cancer patients. We studied the cardiac effects of chemotherapy in a population-based sample of breast cancer patients aged > or = 65 years with long-term follow-up. PATIENTS AND METHODS: In the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, we analyzed treatments and outcomes among women > or = 65 years of age who were diagnosed with stage I to III breast cancer from January 1, 1992 to December 31, 1999. Propensity scores were used to control for baseline heart disease (HD) and other known predictors of chemotherapy, and Cox proportional hazards models were used to estimate the risk of cardiomyopathy (CM), congestive heart failure (CHF), and HD after chemotherapy. RESULTS: Of 31,748 women with stage I to III breast cancer, 5,575 (18%) received chemotherapy. Chemotherapy was associated with younger age, fewer comorbidities, hormone receptor negativity, multiple primary tumors, and advanced disease. Patients who received chemotherapy were less likely than other patients to have pre-existing HD (45% v 55%, respectively; P < .001). The hazard ratios for CM, CHF, and HD for patients treated with doxorubicin (DOX) compared with patients who received no chemotherapy were 2.48 (95% CI, 2.10 to 2.93), 1.38 (95% CI, 1.25 to 1.52), and 1.35 (95% CI, 1.26 to 1.44), respectively. The relative risk of cardiotoxicity among patients who received DOX compared with untreated patients remained elevated 5 years after diagnosis. CONCLUSION: When baseline HD was taken into account, chemotherapy, especially with anthracyclines, was associated with a substantially increased risk of CM. As the number of long-term survivors grows, identifying and minimizing the late effects of treatment will become increasingly important. 相似文献
20.
A P Moore P O Behan W Jacobson W L Armarego 《Journal of neurology, neurosurgery, and psychiatry》1987,50(1):85-87
Tetrahydrobiopterin is an essential co-factor in the natural synthesis of dopamine. Oral tetrahydrobiopterin was given in small doses to four patients with early Parkinson's disease but had no discernible effect. 相似文献