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991.
This study investigates the effects of varying degrees of mother-child language stimulation activities on the test performance of poor Black children and their adolescent mothers.
The sample consisted of 60 mothers paired with their three or four year old children who attended full day preschool. The families were randomly assigned to one of three groups for a twelve week period.
The tests used in the study were the Peabody Picture Vocabulary Test; the Cultural Language Test — Mean Length of Utterance; the Cultural Language Test — Standard English; and the Conversation — Mean Length of Utterance Measure.
Three major findings result from the study:
The sample consisted of 60 mothers paired with their three or four year old children who attended full day preschool. The families were randomly assigned to one of three groups for a twelve week period.
The tests used in the study were the Peabody Picture Vocabulary Test; the Cultural Language Test — Mean Length of Utterance; the Cultural Language Test — Standard English; and the Conversation — Mean Length of Utterance Measure.
Three major findings result from the study:
- The children of mothers provided with intensive training and practice (Group 1) scored significantly higher on all four tests than did the children whose mothers received minimal help (Group 2) or children whose mothers received no help at all (Group 3).
- Group 2 children did not score any higher than did Group 3.
- Group 1 mothers scored significantly higher on all measures.
992.
Mechanisms of proteoglycan inhibition of hydroxyapatite growth 总被引:7,自引:0,他引:7
Summary Purified bovine nasal cartilage proteoglycans (aggregate and subunit containing fractions) and to a lesser degree, chondroitin
4-sulfate of physiological size, retard seeded hydroxyapatite (HA) growthin vitro. The large hydrodynamic size and high charge density of these macromolecules are believed to be associated with the ability
of proteoglycans to inhibit HA formation and growth. We now demonstrate the involvement of the negative charges of proteoglycans
in this inhibition (a) by comparing the inhibitory ability of chondroitin 4-sulfate and its desulfated analog, and (b) by
comparing the growth of HA seed crystals coated either with proteoglycan aggregates or chondroitin 4-sulfate to that of uncoated
crystals. In the desulfation experiments, desulfated chondroitin sulfate was a less efficient HA growth inhibitor than untreated,
undesulfated chondroitin sulfate of similar molecular size. Dextran sulfate showed higher inhibitory effectiveness than unchanged
neutral dextran. Both experiments suggest that sulfate groups play an important role in the regulation of mineral deposition
by proteoglycans. In the coating experiment, precoating of HA seed crystals with proteoglycan aggregates decreased the amount
of HA precipitated as a function of time, suggesting proteoglcans may block the active nucleating sites on HA surface and
slow down the growth process. Chondroitin 4-sulfate has a similar but weaker coating effect. Neural dextran, having little
affinity for HA, had no effect. 相似文献
993.
Jennifer S Storch 《The Journal of neuroscience nursing》2005,37(2):68-71
Lumbar burst fractures occur when unusual force and flexion are placed on the spine, causing the vertebral body to rupture and possibly protrude into the spinal canal. A resulting conus medullaris injury is possible, but not common. In this case presentation, a young man suffered bowel, bladder, and sexual dysfunction after a 25-foot fall that caused a burst fracture of the first lumbar vertebra. The presentation's primary focus is the nursing education needed to care for patients who experience the unusual side effect of conus medullaris injury. The psychosocial aspects attributable to age, developmental stage, and stigma for a young man with these dysfunctions also are explored. 相似文献
994.
Eric A Storch Tanya K Murphy Gary R Geffken Daniel M Bagner Ohel Soto Muhammad Sajid Pam Allen Erin M Killiany Wayne K Goodman 《Journal of clinical child and adolescent psychology》2005,34(2):312-319
This study examined the psychometric properties of the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS; Scahill et al., 1997). Participants were 82 children and adolescents diagnosed with obsessive-compulsive disorder (OCD). Confirmatory factor analyses of 2 previously found models (Obsessions and Compulsions; Disturbance and Severity) yielded poor fit indexes. Exploratory factor analysis supported a model of severity and disturbance with slightly different item content than found by McKay et al. (2003). The internal consistency of the factors was acceptable, and the convergent and divergent validity was supported vis-a-vis correlations with clinician ratings of impairment, self-report measures of depression and anxiety, and parent ratings of Tourette's disorder (TD) symptoms. These findings suggest that the CY-BOCS Total Score may represent an inaccurate assessment of symptom severity and supports the use of the revised Severity and Disturbance factors in assessing illness severity. 相似文献
995.
996.
Assessment of pharmacodynamic vascular response in a phase I trial of combretastatin A4 phosphate. 总被引:6,自引:0,他引:6
Helen L Anderson Jeffrey T Yap Mathew P Miller Adele Robbins Terry Jones Patricia M Price 《Journal of clinical oncology》2003,21(15):2823-2830
PURPOSE: Clinical evaluation of novel agents that target tumor blood vessels requires pharmacodynamic end points that measure vascular damage. Positron emission tomography (PET) was used to measure the effects of the vascular targeting agent combretastatin A4 phosphate (CA4P) on tumor and normal tissue perfusion and blood volume. PATIENTS AND METHODS: Patients with advanced solid tumors were enrolled onto part of a phase I, accelerated-titration, dose-escalation study. The effects of 5 to 114 mg/m2 CA4P on tumor, spleen, and kidney were investigated. Tissue perfusion was measured using oxygen-15 (15O)-labeled water and blood volume was measured using 15O-labeled carbon monoxide (C15O). Scans were performed immediately before, and 30 minutes and 24 hours after the first infusion of each dose level of CA4P. All statistical tests were two sided. RESULTS: PET data were obtained for 13 patients with intrapatient dose escalation. Significant dose-dependent reductions were seen in tumor perfusion 30 minutes after CA4P administration (mean change, -49% at >or= 52 mg/m2; P =.0010). Significant reductions were also seen in tumor blood volume (mean change, -15% at >or= 52 mg/m2; P =.0070). Although by 24 hours there was tumor vascular recovery, for doses >or= 52 mg/m2 the reduction in perfusion remained significant (P =.013). Thirty minutes after CA4P administration borderline significant changes were seen in spleen perfusion (mean change, -35%; P =.018), spleen blood volume (mean change, -18%; P =.022), kidney perfusion (mean change, -6%; P =.026), and kidney blood volume (mean change, -6%; P =.014). No significant changes were seen at 24 hours in spleen or kidney. CONCLUSION: CA4P produces rapid changes in the vasculature of human tumors that can be assessed using PET measurements of tumor perfusion. 相似文献
997.
Mario Mastrolonardo Francesco Loconsole Adele Conte Francesco Rantuccio 《Journal of the European Academy of Dermatology and Venereology》1995,5(1):59-61
We describe the case of a 50-year-old Caucasian woman with Kaposi's sarcoma. After nearly 15 years of very benign course, a sudden exacerbation of the disease led to extensive involvement of the lower limbs and amputation of distal phalanxes of toes on the left foot. Of note, a previously overlooked adenocarcinoma of the sigmoid and oesophageal candidiasis were also detected in the absence of any obvious cause of immunosuppression. 相似文献
998.
999.
V W Storch K H Frank K D Kunze H Porst K U Schentke 《Deutsche Zeitschrift für Verdauungs- und Stoffwechselkrankheiten》1983,43(4):173-184
We report immunohistological findings in liver, spleen, brain, and skeletal muscle of a 23-year-old woman with hepatitis nonA/nonB caused by contaminated anti-D-globulin. She died in a liver coma. At autopsy, a chronic liver dystrophy with cirrhosis was diagnosed. The necrotic areas of the liver showed a collapse of the reticulin framework, newly formed collagen fibres, and diffuse inflammation with immunohistological evidence of IgG, CIq, C9, and fibrinogen. C4 and C9 could be localised in bile thrombi and in the cytoplasm of pseudotubular transformed hepatocytes. In addition, C9 was found in blood vessel walls. A local distribution of HBsAg was found in the cytoplasm and/or the periphery of liver cells. HBcAg could not be detected in any of 5 different regions of the liver. A serum with antibodies to acute phase antigen of nonA/nonB hepatitis stained the cytoplasm and nuclei of (mostly intact) liver cells focally and their cell membranes diffusely. Patchy deposits of IgA and IgM were demonstrated in liver, brain und spleen. Circulating antibodies to cell nuclei and smooth muscle reacted with the patient's own liver and brain but not with spleen and skeletal muscle.--It is suggested that the manifold immunohistological findings in this patient are an expression of the vain attempt of the organism to clear away antigenic material, probably induced by different hepatitis viruses. 相似文献
1000.