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R Klein

Publications and source records attributed to R Klein.

At least 649 records · Page 36Linked to original sources
PubMed1989

Clomiphene citrate.

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Abnormalities, Drug-Induced↗
PubMed1989

The Wisconsin Epidemiologic Study of Diabetic Retinopathy. IX. Four-year incidence and progression of diabetic retinopathy when age at diagnosis is less than 30 years.

Population-based epidemiologic data on the incidence and progression of diabetic retinopathy are important in medical counseling and rehabilitative services and for developing approaches to preventing diabetic retinopathy. We performed a population-based study in southern Wisconsin of insulin-taking diabetic persons diagnosed before 30 years of age. Of the 271 who had no retinopathy at the first visit, 160 (59%) developed it by the time they were reexamined four years later, and 75 (11%) of the 713 free of proliferative diabetic retinopathy developed it. Overall, worsening of retinopathy occurred in 41% of the population, whereas improvement occurred in only 7%. The incidence of proliferative retinopathy rose with increasing duration until 13 to 14 years of diabetes, thereafter remaining between 14% and 17%. These incidence data underscore the need for careful ophthalmologic follow-up of these people.

Adolescent↗
PubMed1989

The Wisconsin Epidemiologic Study of Diabetic Retinopathy. X. Four-year incidence and progression of diabetic retinopathy when age at diagnosis is 30 years or more.

The four-year incidence and progression of retinopathy were investigated in a population-based sample of people with diabetes diagnosed at 30 years of age or older. For insulin users, 73 (47%) of the 154 who did not have any retinopathy at the first visit developed it in the four-year interval, and 31 (7%) of the 418 free of proliferative retinopathy developed it. Worsening of retinopathy occurred in a total of 34% (142/418). For nonusers of insulin, corresponding rates were 34% (110/320) for incidence of any retinopathy, 2% (11/486) for developing proliferative retinopathy, and 25% (121/486) for worsening. These population-based data clearly indicate the risk of retinopathy worsening in a short interval (four years) in a large proportion of people with older-onset diabetes, a group previously thought to be relatively protected from retinopathy. Such patients who make up the largest proportion of diabetic patients in the United States need examination when diabetes is first diagnosed and regular follow-up.

Adult↗
PubMed1989

The relationship of retinal microaneurysm counts to the 4-year progression of diabetic retinopathy.

The relationship of retinal microaneurysms to the progression of diabetic retinopathy over a 4-year period was examined in a population-based sample of diabetic persons. The number of microaneurysms in color stereoscopic fundus photographs of seven standard fields was counted in the eyes of diabetic persons (n = 236) who had only microaneurysms in photographs at the baseline examination. If only one eye was involved (n = 121), the mean number of microaneurysms was 2.3; with bilateral involvement (n = 115), the mean was 9.3 in the more involved eye. The number of microaneurysms at the baseline examination was positively associated with significant progression of retinopathy. This relationship remained after controlling for the level of glycosylated hemoglobin. These data suggest that the number of microaneurysms at baseline is an important predictor of progression of diabetic retinopathy. Microaneurysm counts may prove to be a useful early end point in clinical trials.

Adult↗
PubMed1989

The Wisconsin epidemiological study of diabetic retinopathy: a review.

The WESDR has provided precise estimates of the prevalence, and 4-year incidence and progression of diabetic retinopathy. It has provided evidence of a possible causal relationship between specific risk factors, such as hyperglycemia and the development and progression of retinopathy. Our data support current recommendations for ophthalmologic examinations for people with diabetes. In 1990 we will reexamine the cohort to determine the 10-year incidence and progression of diabetic retinopathy, macular edema, and visual impairment.

Diabetes Mellitus, Type 1↗
PubMed1989

Anti-laminin antibodies in inner ear diseases: a potential marker for infectious and post-infectious processes.

Natural antibodies against laminin (ALA) have been detected recently in some acute and chronic infectious disorders. In our present study sera of a large number of patients with inner ear disorders of unknown etiology (n = 413) were tested for ALA. Control sera were taken from patients with diseases of known infectious etiology and patients with diseases of unknown etiology in which an infectious etiology was suggested. Patients with classical autoimmune diseases as well as healthy blood donors were also included in this study. The highest frequency of ALA was found in patients with sensorineural hearing loss (SNHL) (68%), whereas the incidence of ALA was comparatively uncommon in patients with Menière's disease (14%). In patients with chronic infectious diseases ALA were detected with almost the same frequency as in patients with SNHL. The elevation of the erythrocyte sedimentation rate and the association of ALA-positive SNHL with other chronic inflammatory disorders suggest that ALA might be stimulated by a persisting infectious process. These findings suggest that certain forms of inner ear disorders might have a chronic infectious etiology.

Autoantibodies↗
PubMed1989

Covert visual orienting: hemifield-activation can be mimicked by zoom lens and midlocation placement strategies.

How is attention distributed over visual space when an observer expects a target to occur at one of several possible locations? Two experiments sought to understand the source of the conflict between studies leading to the notions of hemifield activation (Hughes and Zimba 1985) and attentional gradients (Downing and Pinker 1985; Shulman et al. 1985, 1986). subjects were cued to attend one of the 4 corners of an imaginary square centered at fixation, allowing comparison of uncued locations in the cued and uncued hemifields. In one experiment marking of the 4 locations was varied to determine if providing a 'target' for attention is necessary to obtain within-hemifield gradients. RT was faster at the cued location than at the three uncued locations which had equivalent latencies, a pattern that was unaffected by marking of the potential target locations. This result, which is consistent with the notion of a gradient around the attended location is a strong disconfirmation of the hemifield activation hypothesis. The second experiment demonstrated that an unusual procedure for presenting the probe stimuli in Hughes and Zimba (1985) is at least partially responsible for their evidence for uniform hemifield activation. It is proposed that visual attention is directed to visuo-spatial channels with fixed structural properties, and that when attention to two locations is desired, the subject may attend a spatial channel located between them.

Adult↗
PubMed1989

The Wisconsin epidemiologic study of diabetic retinopathy. XI. The incidence of macular edema.

As part of a population-based study of diabetes mellitus, the 4-year incidence of macular edema and its relationship to various risk factors was examined in a group of younger onset insulin-taking persons (n = 610) and older onset persons (n = 652). The presence of macular edema at the baseline and follow-up examinations was determined from gradings of stereoscopic fundus photographs. The overall incidence of macular edema in the younger onset group was 8.2% (50/610); in the group of older onset persons using insulin, 8.4% (23/273) and in the group of those not using insulin, 2.9% (11/379). The incidence of macular edema was associated with higher level of glycosylated hemoglobin, longer duration of diabetes, and more severe retinopathy at the baseline examination in both younger and older onset groups. These data provide accurate population-based estimates of incidence of macular edema, and suggest that the level of glycemia is a significant risk factor for the development of macular edema.

Adolescent↗
PubMed1989

High antibody levels against mouse laminin with specificity for galactosyl-(alpha 1-3)galactose in patients with inner ear diseases.

Sera of 413 patients with inner ear diseases were examined for ELISA binding to mouse laminin and compared to a normal group. Strongly enhanced antilaminin antibody reactions were observed in a large number of patients with sensorineural hearing loss (68%), tinnitus (60%), and sudden deafness (46%), but not in those with Meniere's disease (14%) or normal individuals (8%). Absorption experiments demonstrated that these antibodies are also responsible for the antisarcolemmal antibody pattern in the immunofluorescence test and for the reaction with pig kidney microsomes in the ELISA. Immunochemical studies showed that laminin binding of high or low titer in sera from patients and normal individuals is due to the Gal alpha 1-3Gal epitope present in N-linked oligosaccharides of mouse laminin. No reactions were observed with human laminin, which lacks this epitope. The findings suggest that high levels of antibodies against carbohydrate structures are triggered by persistent infections, providing some new insights about the possible cause of these diseases.

Adult↗
PubMed1989

Proteinuria in Mexican Americans and non-Hispanic whites with NIDDM.

Mexican Americans have a threefold greater prevalence of non-insulin-dependent diabetes mellitus (NIDDM) than non-Hispanic Whites as found in the San Antonio Heart Study, a population-based study of diabetes and cardiovascular disease. In addition, Mexican-American diabetic subjects have higher levels of glycemia than non-Hispanic White diabetic subjects. We therefore hypothesized that the prevalence of clinical proteinuria would be greater among Mexican-American diabetic subjects (n = 317) than among non-Hispanic White diabetic subjects (n = 67). Clinical proteinuria, defined as greater than or equal to 1+ on the Ames Albustix test, was 2.82 times more prevalent in Mexican-American diabetic subjects compared with non-Hispanic White diabetic subjects adjusting for age and duration (95% confidence interval [CI] = 1.05, 7.55; P = .039). After controlling for other possible confounding variables (i.e., glycemia, systolic blood pressure, smoking, and insulin use), the excess of proteinuria in Mexican-American diabetic subjects was only slightly attenuated, although the statistical significance became borderline (odds ratio [OR] = 2.59, 95% CI = 0.91, 7.32; P = .072). The prevalence of microalbuminuria (greater than 30 mg/L) was also significantly higher in Mexican-American diabetic subjects than in non-Hispanic White diabetic subjects (OR = 3.54, 95% CI = 1.28, 9.81; P = .015). We also compared previously diagnosed Mexican-American diabetic subjects (n = 243) from San Antonio with previously diagnosed non-Hispanic White diabetic subjects in Wisconsin (n = 476).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Search performance without eye movements.

Visual search performance (with sets chosen to elicit both serial and parallel search patterns) under two conditions that precluded saccades was compared to the typical situation in which visual inspection of the array is possible. In one condition, the display duration was so brief that any saccades that were executed would be too late to bring the targeted portion of the array into the fovea. In the other, the display remained present until the subject's response, but eye position was monitored and trials with shifts in fixation were excluded from analysis. The latter condition produced search latencies that were nearly identical to those with free inspection. Brief exposure, in contrast, did not produce the pattern typical of serial search, presumably because of strategies induced to deal with the rapid decay of the visual array. It is concluded that saccadic eye movements play little role in the patterns of performance used to infer serial and parallel search, and that brief exposure is not a satisfactory technique for exploring the role of saccadic eye movements in visual search.

Adult↗