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The association of microcephaly and mental retardation with a non-pigmentary retinopathy is described in three siblings of consanguineous parents. The electroretinogram showed the distinctive appearance of markedly attenuated "b" wave but normal "a" wave suggestive of a retinal dystrophy primarily affecting post-receptoral elements in the inner retina. This appears to be an autosomal recessive condition which has not been previously reported.  相似文献   
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Visual-evoked potential evidence of chiasmal hypoplasia   总被引:3,自引:0,他引:3  
PURPOSE: To show that chiasmal hypoplasia or aplasia need not be an isolated developmental anomaly and to examine the spectrum of associated clinical findings to explore the possibility that these patients may represent a phenotypic manifestation of a developmental gene anomaly. DESIGN: An observational case series. PARTICIPANTS: Five infants, between several weeks and 7 months of age, in whom the electrophysiologic characteristic of chiasmal hypoplasia had been noted were included. METHODS: Flash electroretinography and flash and pattern visual-evoked potentials (VEPs) were elicited from all patients. Clinical ophthalmologic examinations, including funduscopy, were performed, and all patients had magnetic resonance imaging (MRI) brain scans. MAIN OUTCOME MEASURES: The occipital distribution of monocular VEP response peaks was studied. The symmetry of lateral channel responses was compared for monocular stimulation. RESULTS: All five patients had a crossed asymmetry in the monocular VEP occipital distribution, which is consistent with a paucity of fibers crossing at the chiasm. The MRI findings supported this electrophysiologic observation, illustrating degrees of chiasmal hypoplasia and variable coincidence of other midline abnormalities of the brain. Optic disc appearances varied from normal to hypoplastic and colobomatous. CONCLUSIONS: The ophthalmologic and MRI findings of five patients who showed a crossed asymmetry in monocular flash VEPs are consistent with a paucity of axons crossing at the chiasm. The similarities between achiasmia in humans and mice due to a Pax2 gene anomaly are discussed.  相似文献   
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To test the hypothesis that Graves' dermopathy is due to cross-reactivity of thyroid autoantibody(ies) with a cellular target in pretibial skin, we tested the serum and serum immunoglobulin fraction of 20 such patients for their effects on the metabolic activities of cultured thyrocytes (rat FRTL cells), human pretibial skin fibroblasts, and human fibroblasts of other origins. The incorporation of 3H-labeled thymidine, amino acids, and glucosamine into DNA, protein, and glycosaminoglycans, respectively, was measured. TSH and the serum of each of the 20 patients with Graves' dermopathy markedly stimulated the synthesis of DNA, protein, and glycosaminoglycans by FRTL cells, but not by fibroblasts, whereas assays of serum from 38 of 40 patients with Graves' disease without dermopathy did not stimulate these processes in FRTL cells more than normal serum. Stimulatory activity was associated with immunoglobulins. Serum dermopathy-associated antibodies disappeared with the disappearance of the skin lesions. These results suggest that the serum of patients with dermopathy contains antibodies that recognize a component of the TSH receptor different from that recognized by serum of Graves' patients without dermopathy, the former acting in some manner to induce lesions in pretibial skin. The skin target remains unidentified.  相似文献   
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ABSTRACT

Anxiety is the most prevalent psychiatric disturbance in childhood effecting typically 15–20% of all youth. It has been associated with attachment insecurity and reduced competence in peer relations. Prior work has been limited by including mainly White samples, relying on questionnaires, and applying a cross-sectional design. The present study addressed these limitations by considering how at-risk non-White youth (n = 34) responded to the Friends and Family Interview (FFI) in middle childhood and how this linked up with anxiety symptoms and an anxiety diagnosis three years later in early adolescence. Five dimensions of secure attachment, namely, (i) to mother, (ii) to father, (iii) coherence, (iv) developmental understanding, and (v) social competence and quality of contact with best friend in middle childhood, were found to correlate significantly (and negatively) with self-reported anxiety symptoms. Linear regression results showed independent influences of female gender, and (low) quality of best friend contact as the most efficient model predicting anxiety symptoms. Logistic regression results suggested a model that included female gender, low social competence, and immature developmental understanding as efficient predictors of an anxiety diagnosis, evident in only 18% of the sample. These results point to the usefulness of after-school programs for at-risk minority youth in promoting peer competence, developmental awareness, and minimizing anxiety difficulties.  相似文献   
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BACKGROUND Abnormal liver function tests(LFTs) in post-liver transplant(LT) patients pose a challenge in the timing and selection of diagnostic modalities.There are little data regarding the accuracy of endoscopic retrograde cholangiopancreatography(ERCP) and liver biopsy(LB) in diagnosing post-transplant complications.AIM To evaluate the diagnostic performance of ERCP and LB in patients with nonvascular post-LT complications.METHODS This single-center retrospective study evaluated patients undergoing both ERCP and LB for evaluation of elevated LFTs within 6 mo of LT from 2000 to 2017.Diagnostic operating characteristics including accuracy,sensitivity and specificity for various diagnoses were calculated for ERCP and LB.The R factor(ratio of alkaline phosphatase to alanine aminotransferase) was also calculated for each patient.RESULTS Of the 1284 patients who underwent LT,91 patients(74.7% males,mean age of 51)were analyzed.Anastomotic strictures(AS,24.2 %),acute cellular rejection(ACR,11 %) and concurrent AS/ACR(14.3 %) were the most common diagnoses.ERCP carried an accuracy of 79.1%(95 % CI:69.3-86.9),LB had an accuracy of 93.4%(95 % CI:86.2-97.5),and the combination of the two had an accuracy of 100%(95 % CI:96-100).There was no difference between patients with AS and ACR in mean R factor(AS:1.9 vs ACR:1.1, P=0.24).Adverse events did not differ between the two tests(ERCP:3.1% vs LB:1.1%,P=0.31).CONCLUSION In patients with abnormal LFTs after LT without vascular complications,the combination of LB and ERCP carries low risk and improves diagnostic accuracy over either test alone.  相似文献   
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We prepared artificial vesicles that are lysed upon cell-mediated immunological attack by human lymphocytes. These vesicles are made from a mixture of dimyristoyl lecithin, dipalmitoyl lecithin, and cholesterol, have eye muscle membrane protein (EMP) inserted into the bilayer wall, and contain intravesicular (99m)Tc marker. Injury to the vesicular membrane was assessed by measurement of (99m)Tc release. Thyroglobulin (Tg) and Tg-anti-Tg complex (TgA) bind to EMP-vesicles to an extent equal to or greater than to native eye muscle membranes in vitro; this binding requires the presence of normal human IgG. The role of Tg, TgA, IgG, and peripheral blood lymphocytes in altering membrane permeability was analyzed. Incubation of vesicles for up to 3 hr alone, with added IgG alone, or with further addition of Tg or TgA did not result in (99m)Tc release. Addition of lymphocytes from normal donors to the above four preparations showed release in the presence of TgA. Lymphocytes from each of eight patients with Graves ophthalmopathy caused release not only in the presence of TgA, but also in the presence of Tg. Separation of a patient's lymphocytes into high- and low-affinity rosette-formers (T and K cells, respectively) showed that cell-mediated vesicle lysis in the presence of TgA was greater with K cells than with T cells, while vesicle lysis in the presence of Tg was greater with T cells than with K cells. Vesicles made with inserted Tg but lacking EMP were not lysed by such T cells. Lymphocytes failed to induce permeability changes in vesicles containing other inserted proteins obtained from human nonextraocular muscle, liver, spleen, or adrenal, even if Tg or TgA were present. The results support the concept that muscle cell damage in Graves ophthalmopathy is immunological, cell-mediated, and of two types: (i) K lymphocytes reacting to immune complex, TgA, on the eye muscle cell surface (i.e., antibody-dependent cytotoxicity) and (ii) sensitized T lymphocytes reacting to Tg on the eye muscle cell surface. An antigenic role for EMP is possible, but has not been unequivocally proven.  相似文献   
10.
Background

The presumed mechanism of rib fractures in abuse is violent grasping of the torso causing anterior–posterior chest compression. We hypothesized an asymmetrical distribution of rib fractures in abused infants given the greater incidence of right-hand dominance within the general population.

Objective

The objective of this study was to characterize rib fractures in abused children, particularly sidedness; additionally, we evaluated the sidedness of other abusive skeletal fractures.

Materials and methods

We reviewed medical records from abused children (0–18 months old) with rib fractures. We also retrospectively reviewed their radiographs to determine characteristics of rib fractures (number, side, rib region, level, acuity) and other skeletal fractures (number, side, location), as well as differences in the distribution of rib and other skeletal fractures.

Results

A total of 360 rib fractures were identified on 273 individual ribs involving 78 abused children. Sixty-three children (81%) had multiple rib fractures. There was a significantly greater number of left-side rib fractures (67%) than right-side fractures (P<0.001). Fractures were most often identified in the posterior and lateral regions and mid level of the ribcage (Ribs 5 through 8). Fifty-four percent of subjects had other skeletal fractures; these non-rib fractures were also predominantly on the left side (P=0.006).

Conclusion

In our study of abused children, there was a higher incidence of rib fractures in the posterior, lateral and mid-level locations. Additionally, we found a predominance of left-side rib and other skeletal fractures. Further research is needed to understand whether factors such as perpetrator handedness are associated with these unequal distributions of fractures in abused children.

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