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The expression of an X-linked defect in the CBA/N strain of mice has been found to result in a number of immune abnormalities. These include low responsiveness to antigens and a greatly reduced ability to respond to many of the common B cell mitogens. An in vitro manifestation of this condition is the virtual inability of CBA/N B cells to form colonies in lipopolysaccharide (LPS)-containing semisolid agar cultures. In this report we show evidence that the colony-forming ability of CBA/N spleen cells can be effectively restored by the bone marrow stromal-derived cell line S17. Spleen cells from 4-5-week-old homozygous CBA/N female mice were grown in double-layer agar cultures containing S17 feeder layers. Control cultures contained the fibroblast-like cell line 95.17 or were treated with medium alone. It was found that at an input cell concentration of 10(4) cells per plate, CBA/N colony formation was increased from a frequency of approximately 1 in 5,000 to 1 in 50 total splenic cells. Studies with purified surface immunoglobulin-positive cells indicate the direct involvement of S17 in this process. The CBA/N colonies formed were dependent on the presence of a mitogen (LPS) and secreted detectable amounts of IgM. Major implications of these findings and the application of this assay system to study the CBA/N defect have been discussed.  相似文献   
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Chaetomium is a soil fungus of which more than 180 species are now known. Most species cause degradation of cellulose-rich substrates, such as components in soil, straw or wood. Growth ofChaetomium globosum is often stimulated in the presence ofAspergillus fumigatus, which excretes such compounds as sugar phosphates and phospho-glyceric acid. A 73-year-old woman, with longstanding pain and secretion from her left maxillary sinus, was admitted to hospital where an infundibulectomy was performed. Histological examination showed necrotic material with hyphae ofA. fumigatus and perithecia ofChaetomium sp. The latter fungus is rarely pathogenic to man.  相似文献   
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Purpose:This study aimed to evaluate the knowledge, awareness and attitude of eye donation among non-clinical staff of tertiary eye hospitals and to convey a positive attitude toward eye donation by enhancing their awareness and knowledge.Methods:An online cross-sectional study was conducted among the non-clinical staff from all centers of a tertiary eye care hospital across Tamil Nadu. Quiz link was emailed to non-clinical staff of all the centers. On completion of the quiz, the participants viewed their respective scores and the correct answers to all questions. This activity was presumed to subsequently improve their knowledge and clear up the myths on eye donation.Results:Two hundred twenty-eight non-clinical staff from 11 hospitals participated in the quiz. Mean age was 35.3 ± 9.8 years and 130 were female staff (57.05%). One hundred eighty-one participants (79.39%) scored over 50% of the total 17 queries. One hundred eighty-six (81.58%) and 142 (62.28%) participants scored over 50% in the awareness section and knowledge section, respectively. Eye bank volunteers (73, 32.02%) were the main source of information. Twenty-four (10.53%) had already taken pledge for eye donation and 175 (76.75%) were willing to pledge, 29 (12.72%) were not willing to pledge. Twenty-two out of these 29 (75.86%) had no specific reason for not pledging. Family, religious reasons, lack of clarity and fear were least cited reasons (13.79%).Conclusion:Non-clinical staff of an eye hospital are easily approachable and are expected to be more knowledgeable by the general public around them. They might act as primary motivators in raising awareness within their family, friends, relatives and neighbors.  相似文献   
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Purpose:To assess the retinal manifestations of Parkinson’s disease using optical coherence tomography.Methods:A prospective case-control study comparing 30 eyes from 15 patients with Parkinson’s disease and 22 eyes from 11 healthy age-matched controls. Total macular subfield thickness and the thickness of the ganglion cell layer, nerve fiber layer, and peripapillary retinal nerve fiber layer were measured with spectral-domain optical coherence tomography (SD-OCT).Results:The mean age of PD patients was 68.4 years ± 10.64 (range: 46–82) and in the control group was 66.36 ± 5.22 (range: 64–68). The average disease duration in patients with PD was 6.7 ± 2.8 years (range: 2–10 years). The mean best-corrected visual acuity in PD was 20/26 and 20/20 in controls, with P = 0.0059, which was significant. Significant difference was also found in the contrast sensitivity between both groups. Structural differences in the central macular thickness (P = 0.0001), subfield thicknesses in the superior (P = 0.003), inferior (P = 0.001), nasal (P = 0.004), and temporal subfields (P = 0.017) was seen. Severe thinning of the ganglion cell layer was seen in PD patients (P = 0.000) as well as of the nerve fiber layer (P = 0.004). Peripapillary retinal nerve fiber thickness measured showed significant thinning in superotemporal (P = 0.000), superonasal (P = 0.04), inferonasal (P = 0.000), inferotemporal (P = 0.000), nasal (P = 0.000), and temporal quadrants (P = 0.000).Conclusion:Visual dysfunction was observed in patients with PD along with structural alterations on OCT, which included macular volumes, ganglion cell layer, and peripapillary retinal nerve fiber layer.  相似文献   
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The emergence of smartphone-based imaging devices has been a boon in the field of ophthalmology, especially in obtaining high-quality ocular images. They can be specialized and utilized for imaging-specific regions of the eye. Among the multitude of applications of smartphone-based imaging, one of the upcoming major use is to image the microbiological world. Previous few reports have described attaching magnifying lenses of various types to the smartphone camera and transforming it into a microscope for imaging fungal hyphae and ocular surface parasites. We describe a novel technique of attaching the smartphone-based intraocular lens microscope (IOLSCOPE) to the slit lamp, thereby utilizing the slit lamp joystick for moving the smartphone over the concerned slide specimen to make it steady and obtain images of high resolution. This innovative do-it-yourself novel modification is especially useful in peripheral centers, vision centers, and local clinics for immediate screening and identification of microbial pathogens such as fungi and ocular surface parasites.  相似文献   
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Purpose:To analyze the reasons for delay in cataract surgery in patients with advanced cataracts during the COVID-19 pandemic.Methods:This was a prospective, cross-sectional, multicenter questionnaire study which included patients with mature cataract, nuclear sclerotic cataract grade IV, and cataracts with best corrected visual acuity (BCVA) <5/60, during the COVID-19 pandemic from December 2020 to April 2021. Reasons for delay in presentation to the hospital were analyzed.Results:One thousand four hundred seventy two patients were recruited with advanced cataracts. Absence of ophthalmic care nearby (44.2%), lack of awareness regarding elective surgeries (42.6%), lack of public transportation (37%), fear of contracting COVID-19 (23.4%), and waiting for outreach camps (20.4%) were found to be the reasons behind the delay in cataract surgery. 53.7% of the patients had worsening of defective vision and 55.3% of them had difficulty in carrying out activities of family living. 30.8% of the patients faced difficulty in commuting and 8.4% of the patients suffered a fall during this pandemic due to worsening of the visual acuity.Conclusion:The lockdown imposed during the pandemic has created a significant backlog of patients who are progressing to advanced cataracts due to lack of ophthalmic care nearby, lack of awareness regarding elective surgeries, lack of public transportation, and no outreach camps. Proactive measures to deal with this backlog are of utmost need to prevent blindness due to cataract.  相似文献   
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