Summary. Measurements of the glucose to mann• tracer concentration ratios in renal venous blood and renal lymph of rats supported the hypothesis that reabsorbed glucose may have direct access to renal lymph by passage through the interstitium.Recent morphological investigations have contributed to the clarification of the structural relationship between the renal cortical interstitium and the lymphatic system. Thus, under normal conditions the volume of the interstitium has been measured by morphometric techniques and was found to constitute approximately 4-7% of the renal cortex 2-4. The interstitial space appears as variably narrow slits, and at some other places as wider gaps between tubules and per• blood capillaries. Lymphatic vessels have been seen to originate regularly in the loose connective tissue around the interlobular blood vessels 5 and in the vicinity of glomeruli 6. The morphological evidence thus suggests that the interstitium in the renal cortex through which the bulk of tubular reabsorbate flows, may be separated by a considerable distance from the initial lymph capillaries. Functionally, it has been generally assumed that renal lymph is derived from the cortical interstitium. However, it has not as yet been determined whether those interstitial spaces through which tubular reabsorbate flows do contribute to renal lymph. The experiments described here were aimed at the finding of a constituent of tubular reabsorbate, specifically of reabsorbed glucose, in renal lymph. The results suggest that the concentration of glucose in renal hilar lymph is higher than in renal venous plasma, and that the source of the excess glucose in renal lymph is the tubular reabsorbate.Methods. Sprague-Dawley rats, weighing between 180 and 250 g, were anesthetized with Inactin, 100 mg/kg b.wt. The femural blood vessels on both sides, the left ureter and a left renal hilar lymphatic vessel were cannulated as described earlier 7. Blood from the left renal vein was collected by a non-occluding PE-10 catheter. A mixture of 14C-glucose and 3H-mannitol tracers was administered to the rats in constant i.v. infusion. After a near stabilization of the concentration ratio (R) of lac-glucose/3H-mannitol in arterial plasma serial samples of this ratio in arterial plasma urine, lymph and renal venous plasma were determined (Rap, Ru, R 1 and Rvp, respectively). Because the molecular weights and structures of glucose and mannitol are nearly identical, it was assumed that in the kidney both these tracers are affected equally by diffusion and convective transport. This assumption was confirmed experimentally after the administration of phlorizin (40 mg/kg): When the tubular reabsorption of glucose was blocked by phlorizin, 14 3 there was no difference between the C-glucose/H-mannitol ratios in arterial and renal venous plasma, urine and renal lymph, i.e. R,. ~ Rvp ~ R1 ~ Ru.Results. The results~are illustrated in the The statistical comparison of the venous and hilar lymph ratios was carried out within each animal by means of both...
WISC-Rs and Stanford-Binets were administered to 50 children with developmental disabilities referred for comprehensive evaluations. Although the two IQs correlated highly and significantly, it was found that 5470 of the children received different classifications using the two instruments. Thus, testers should be aware that different classifications of intellectual level may be derived for the same child depending upon which test is used.Recently, two of the most widely used intelligence tests for children have been either revised or restandardized, the WISC-R in 1974 and the Stanford-Binet in 1972. An understanding of the various relationships between these is necessary since important judgments and academic placement decisions frequently are made using their scores. Usually, these tests are administered by school psychologists and psychometrists, psychologists in diagnostic and evaluation clinics, or private practitioners. It is our hope that the data presented for children with developmental disabilities will help professionals understand the danger of relying solely on I& scores in making their decisions. METHOD SubjectsThe subjects were 50 children (36 boys and 14 girls) between the ages of 6 years-0 months and 15 years-11 months who had been referred for evaluation primarily for possible mental retardation and/or learning difficulties. These children often had other developmental problems such as visual-motor difficulties and central nervous system dysfunction. No child was severely or profoundly retarded. The 50 subjects were divided into two groups of 25 each, based on a chronological age median split. The "younger" group had an age range from 6 years-0 months to 8 years-5 months-28 days (x = 7-5 years; SD = 9 months). The range of the "older" group was 8-6-11 to 15-11-0 years (x = 10.9 years; SD = 1.9 years).Each child was administered individually, in counterbalanced order, both the WISC-R and Binet (1972 restandardization) as part of a comprehensive psychological/developmental assessment. Intelligence ClassificationsThe intelligence classifications employed were based, in part, on the AAMD terminology (Brison, 1967). The WISC-R (Wechsler, 1974) and Stanford-Binet (Terman and Merrill, 1973) classifications were used for those children functioning at higher levels. These classification categories were Superior (I& = 120-129), High Average (I& = 110-119), Average (I& = 90-log), Low Average (I& = SO-89), Borderline (I& = 70-79), Mild (Binet, I& = 52-69; Wechsler, I& = 55-69), Moderate MR (Binet, I& = 36-51; Wechsler, I& = 40-54).The research assistance of &even N e e is acknowledged gratefully. Opinions expressed are the authors' and do not necessarily reflect those of the agencies noted above.Requests for reprints should be sent to Allan S. Bloom,
Administered the WISC-R, Revised Stanford-Binet, Bender, VMI, and WRAT to 50 children referred for a multidisciplinary evaluation of developmental disabilities. The correlations among the various WISC-R measures (Standard Scores and IQs) and Binet IQ were significant, with relatively strong relationships among the Binet IQ and those WISC-R subtests that require concentration, short-term auditory memory, visual-motor integration, and the acquisition of new learning. Data showed that the Binet MA correlated as well or better with the other tests than did the various scores from the WISC-R.
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