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991.
We report six eyes with foveal white lesions and associated "abortive" retinal neovascularization. Over a two- to six-year follow-up period the clinical course was benign and the eyes maintained visual acuities of 20/20 to 20/30.  相似文献   
992.
This study presents survey data bearing on the prevalence of young children (0–4) at risk for the development of handicapping conditions, and projects a method for operationalizing the assessment of risk in this population. A statewide survey of 1,551 families in Ohio was conducted through a telephone interview structured to identify young children at risk for the development of handicapping conditions. It was found that over a sixth (17.8 percent) of the 2,133 children were at risk for developing handicapping conditions, based on a criterion of the presence of at least two risk factors. Five percent of the children sampled were identified as having three or more risk factors present. The implications of these results for prevention and service planning are discussed.This study was supported by a grant from the Ohio Department of Mental Retardation and Developmental Disabilities, authorized under P.L. 95-602. The research, Exploring and Expanding Early Intervention Services was implemented through the Southwest Community Health Centers, Inc., in Columbus, Ohio.  相似文献   
993.
We evaluated the toxicity, pharmacokinetics, and localization of a monoclonal IgG2 alpha murine anti-human melanoma (gp240) antibody (ZME-018) that recognizes a tumor-associated cell surface glycoprotein of 240,000 molecular weight present in most melanomas. The antibody was conjugated with DTPA (diethylenetriamine pentaacetic acid) and labeled by chelation of 111In. One mg of antibody labeled with 5 mCi of 111In was infused, together with 0 to 40 mg of "cold" carrier ZME-018. The blood clearance, urinary excretion, and in vivo localization were determined in 26 patients. Scintigraphic images were obtained at 24 hours and 72 hours in all patients. Mild toxicity occurred in one patient. The half-time clearance of labeled monoclonal murine antibody (MoAb) from the blood increased from 16.1 hours at an antibody dose of 1 mg to 35.9 hours at 40 mg. Males showed faster clearance from the blood than did females or a single castrated male, perhaps due to selective concentration of antibody in the testes. Nonspecific uptake in liver, spleen, bone marrow, and intestine was seen in all patients. The percentage of known metastatic foci detected increased with the total dosage of antibody, from 23% at doses less than or equal to 5 mg, to 65%, 87% and 78% for 10, 20, and 40 mg, respectively. We conclude that at doses of greater than or equal to 10 mg, ZME-018 is a safe and potentially useful agent for the scintigraphic detection of metastatic malignant melanoma.  相似文献   
994.
The authors have investigated digital subtraction angiography (DSA) for the differential diagnosis of breast lesions detected initially by mammography. Eighteen patients scheduled for biopsy first underwent digital subtraction angiography of the breast (DSAB). Criteria for malignancy included the presence of abnormal vessels and a "blush" in the area of the lesion. A total of 17 lesions are currently available for histopathologic correlation. Although this is a small series, the initial results of DSAB suggest its potential utility for differentiating between benign and malignant lesions.  相似文献   
995.
996.
Journal of Neuro-Oncology - Molecular data has become an essential part of the updated World Health Organization (WHO) grading of central nervous system tumors. However, stereotactic needle...  相似文献   
997.
PURPOSE: To describe a case of spontaneous central retinal artery occlusion in a young man with hemoglobin sickle cell disease.METHOD: Case report.RESULTS: A 31-year-old African-American man with a history of hemoglobin SC (sickle C) disease developed sudden painless loss of vision in the right eye. Medical history was remarkable for the recent history of a mild sickle crisis, but no other systemic illness or contributing factors. Central retinal artery occlusion was diagnosed with retinal whitening, cherry red spot, and delayed arteriovenous transit on fluorescein angiography. Over the ensuing week, the patient had visual recovery to 20/60 in the absence of therapeutic intervention.CONCLUSION: Central retinal artery occlusion has been reported in sickle cell hemoglobinopathies (ie, SS, S-thal, sickle trait, and SC), but the association with double heterozygous SC disease is rare. Most reports have described additional contributing factors, such as trauma or concomitant systemic illness, to help account for the central retinal artery occlusion. The present case suggests that SC disease alone is sufficient for the development of central retinal artery occlusion.  相似文献   
998.

Background

Heart rate variability (HRV) analysis is uncommonly undertaken in patients with atrial fibrillation (AF) due to an assumption that ventricular response is random. We sought to determine the effects of head‐up tilt (HUT), a stimulus known to elicit an autonomic response, on HRV in patients with AF; we contrasted the findings with those of patients in sinus rhythm (SR).

Methods

Consecutive, clinically indicated tilt tests were examined for 207 patients: 176 in SR, 31 in AF. Patients in AF were compared to an age‐matched SR cohort (n = 69). Five minute windows immediately before and after tilting were analyzed using time‐domain, frequency‐domain and nonlinear HRV parameters. Continuous, noninvasive assessment of blood pressure, heart rate and stroke volume were available in the majority of patients.

Results

There were significant differences at baseline in all HRV parameters between AF and age matched SR. HUT produced significant hemodynamic changes, regardless of cardiac rhythm. Coincident with these hemodynamic changes, patients in AF had a significant increase in median [quartile 1, 2] DFA‐α2 (+0.14 [?0.03, 0.32], p < .005) and a decrease in sample entropy (?0.17 [?0.50, ?0.01], p < .005).

Conclusion

In the SR cohort, increasing age was associated with fewer HRV changes on tilting. Patients with AF had blunted HRV responses to tilting, mirroring those seen in an age matched SR group. It is feasible to measure HRV in patients with AF and the changes observed on HUT are comparable to those seen in patients in sinus rhythm.
  相似文献   
999.
Kinesin participates in melanosomal movement along melanocyte dendrites   总被引:6,自引:0,他引:6  
Movement of melanosomes along melanocyte dendrites is necessary for the transfer of melanin pigment from melanocytes to basal and suprabasal keratinocytes, an event critical to epidermal photoprotection and maintenance of normal skin color. Recent murine data suggest that in melanocyte dendrites the microtubule-associated melanosome movement is bidirectional and that actin-associated myosin V secures the peripheral melanosomes, preparing them to be transferred to surrounding keratinocytes. We now report that human melanocytes express high levels of kinesin, a molecule that participates in microtubule-associated transport of organelles in other cell types, and that ultrastructurally kinesin molecules are closely associated with melanosomes. To determine whether kinesin participates in melanosomal transport, cultured melanocytes were treated with sense or antisense oligonucleotides complementary to kinesin heavy chain sequences. Antisense oligonucleotides decreased kinesin protein levels and inhibited the bidirectional movement of the melanosomes, promoting their backward movement. Furthermore, guinea pigs were exposed to ultraviolet B irradiation, known to enhance transport of melanosomes from melanocytes to epidermal keratinocytes, and then were treated with kinesin sense or antisense oligonucleotides. The areas that were treated with kinesin antisense oligonucleotides showed significantly less pigmentation clinically and histologically than control (sense) oligonucleotide-treated areas. As observed ultrastructurally, in antisense-treated areas melanosomes remained in melanocyte dendrites but over several days were not transferred to the surrounding keratinocytes. Our study supports a major role for kinesin in microtubule-associated anterograde melanosomal transport in human melanocyte dendrites.  相似文献   
1000.
The importance of timing of intravenous streptokinase (SK) administration in patients with acute myocardial infarction (AMI) was evaluated. Intravenous SK, 750,000 U, was administered within 4 hours of the onset of ischemic chest pain to 72 consecutive patients having their first AMI. Six days later, cardiac catheterization was performed to calculate global ejection fraction (EF), and computer-derived infarct-related regional EF and dysfunction index were also determined; electrocardiograms were recorded, from which QRS scores could be calculated to estimate infarct size. Of 19 patients who had an anterior AMI, 12 (63%) who received intravenous SK within 2 hours after onset of pain sustained only minimal damage in terms of global EF, infarct-related EF, dysfunction index and QRS score. All 10 patients who received SK 2 to 4 hours after pain onset had large infarcts (p less than 0.001). Of the former group, 11 of 12 patients (91%) whose pain was relieved within 1.5 hours of intravenous SK administration (presumably due to successful reperfusion) had a good outcome, whereas all 7 whose pain lasted longer did poorly (p less than 0.001). Furthermore, among patients with anterior AMI, 11 of 14 (79%) whose pain was relieved within 3.5 hours of onset had small infarcts, compared with none of the 12 patients whose pain lasted longer (p less than 0.0001). In inferior AMI, the critical time between onset of pain and initiation of intravenous SK was 1.5 hours (p less than 0.05). The timing of initiation of thrombolytic therapy and the total pain duration are critical in determining outcome in AMI, and time intervals vary depending on infarct localization.  相似文献   
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