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881.
Effects of primary glaucoma on sleep quality and daytime sleepiness of patients residing at an equatorial latitude 下载免费PDF全文
Jacob YH Chin Zhi Hong Toh Ying Tai Lo Hannah TY Wang Elizabeth YW Poh Chun Hau Chu Owen Kim Hee Boon Ang Lim Vernon KY Yong Augustinus Laude Hon Tym Wong Leonard WL Yip 《国际眼科》2020,13(9):1451-1458
AIM: To investigate the efficacy and the safety of umbilical cord derived mesenchymal stem cell (UC-MSC) implantation in patients with retinitis pigmentosa (RP). METHODS: This prospective, single-center, phase 3 clinical study enrolled 124 eyes of 82 RP patients. The patients received 5 million UC-MSCs to the suprachoroidal area with a surgical procedure. Patients were evaluated on the 1st day, 1st and 6th month postoperatively. Best corrected visual acuity (BCVA), anterior segment and fundus examinations, color photography, optical coherence tomography (OCT), and visual ?eld (VF) tests were carried out at each visit. Fundus ?uorescein angiography (FFA) and multifocal electroretinography (mfERG) recordings were performed at the end of the 6th month. Ocular and systemic adverse events of the surgical procedure were also noted. RESULTS: All of the 82 patients completed the 6-month follow-up period. None of them had any serious systemic or ocular complications. There were statistically significant improvements in BCVA and VF during the study (all P<0.05). The amplitudes of the P1 waves in the central areas showed significant improvements in mfERG recordings. There were also significant increases in implicit times of P1 waves in the central areas. CONCLUSION: Suprachoroidal administration of UC-MSCs has beneficial effect on BCVA, VF, and mfERG measurements during the 6-month follow-up period. Cell mediated therapy based on the secretion of growth factors (GFs) seems to be an effective and safe option for degenerative retinal diseases. 相似文献
882.
OBJECTIVE: To describe the gallbladder ghost triad and evaluate its usefulness in the sonographic diagnosis of extrahepatic biliary atresia (BA). METHODS: From October 1997 to February 2002, 217 fasted infants with cholestatic jaundice aged 2-12 weeks were examined sonographically. We defined the gallbladder ghost triad as gallbladder length <1.9 cm, lack of smooth/complete echogenic mucosal lining with an indistinct wall and irregular/lobular contour, and used it as a criteria for BA. Gallbladder wall thickness, triangular cord, diffuse periportal echogenicity and hepatic artery calibre were also recorded. Diagnosis of BA was confirmed surgically and histologically. RESULTS: Thirty of 31 babies with BA demonstrated the gallbladder ghost triad. No false-positives were recorded. The 31st BA baby showed a normal gallbladder at 6 weeks, but developed the ghost triad at 8 weeks. Gallbladder wall thickening was seen in 46/186 non-BA babies, but not in BA. Triangular cord was observed in 24/31 babies. Twenty-two of 186 non-BA babies and 5/31 BA babies showed diffuse periportal echogenicity. The hepatic artery appeared more prominent in BA. All 31 babies diagnosed sonographically as BA had surgery. Three non-BA babies had "negative" laparotomies showing hypoplastic bile ducts. CONCLUSIONS: The gallbladder ghost triad is a very accurate sign of BA. Indeterminate cases require close follow-up. 相似文献
883.
This paper presents a termination criterion for active contour that does not involve alteration of the energy functional. The criterion is based on the area difference of the contour during evolution. In this criterion, the evolution of the contour terminates when the area difference fluctuates around a constant. The termination criterion is tested using parametric gradient vector flow active contour with contour resampling and normal force selection. The usefulness of the criterion is shown through its trend, speed, accuracy, shape insensitivity, and insensitivity to contour resampling. The metric used in the proposed criterion demonstrated a steadily decreasing trend. For automatic implementation in which different shapes need to be segmented, the proposed criterion demonstrated almost 50% and 60% total time reduction while achieving similar accuracy as compared with the pixel movement-based method in the segmentation of synthetic and real medical images, respectively. Our results also show that the proposed termination criterion is insensitive to shape variation and contour resampling. The criterion also possesses potential to be used for other kinds of snakes. 相似文献
884.
Do different lamivudine‐resistant hepatitis B genotypes carry the same risk of entecavir resistance?
Guan Huei Lee Myat Oo Aung Yock Young Dan Yin Mei Lee Belinda Mak How Cheng Low Kieron Lim Maung Aye Thwin Poh Seng Tan Seng Gee Lim 《Journal of medical virology》2013,85(1):26-33
Entecavir switch is one of the treatment options for lamivudine‐resistant hepatitis B (HBV) patients in Asia. This study examined the outcome of patients with different baseline resistance genotypes in a cohort study. In this study, 14 patients with chronic HBV were treated with entecavir 1 mg/day for 5 years. Enrolment criteria include: documented lamivudine resistant mutations, treatment with adefovir 10 mg/day for at least 24 weeks, and Child‐Pugh score <7. Most had previous failed adefovir therapy and compensated cirrhosis of the liver. Clinical outcomes, liver biochemistries, and HBV DNA were monitored regularly. Patients with virologic breakthrough were rescued with add‐on adefovir. At the end of the treatment period, the mean HBV DNA fell from 5.92 × 106 (baseline) to 3.67 × 101 IU/ml. The presence of a HBV polymerase rtM204V mutation at the baseline was found to be the major risk factor for adverse outcomes. Compared to the patients with the rtM204I mutant, patients with the rtM204V mutant had increased risk of virologic breakthrough (80% vs. 0%, P = 0.010) requiring add‐on adefovir, slower virologic responses (log rank test, P = 0.0011), failure to reach undetectable HBV DNA levels (60% vs. 0%, P = 0.045), and higher risk of entecavir‐resistance (60% vs. 0%, P = 0.045). All the patients with rtM204I and rtA181 mutants had undetectable HBV DNA from 18th month. In summary, lamivudine‐resistant HBV patients with the rtM204V mutation have the highest risk of developing entecavir resistance, and entecavir monotherapy should be avoided. Those with the rtM204I and rtA181V mutations may have lower risks, but regular surveillance for viral breakthrough is required. J. Med. Virol. 85:26–33, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
885.
Ductal carcinoma in situ with spindle cells: a potential diagnostic pitfall in the evaluation of breast lesions 总被引:4,自引:0,他引:4
AIMS: To evaluate the morphological features of 11 cases of breast ductal carcinoma in situ (DCIS) with spindle cells and to propose an approach to distinguish it from benign mimics. The association with neuroendocrine differentiation was also investigated. METHODS: Cases of breast DCIS with a spindle cell component diagnosed in the Department of Pathology, Singapore General Hospital, between June 1996 and January 2003, were included in the study. The histological characteristics were documented, and immunohistochemistry for neuroendocrine markers, hormone receptors, cerbB2, smooth muscle actin (SMA) and high-molecular-weight (HMW) cytokeratins, was carried out. Electron microscopy was carried out on reprocessed paraffin-embedded material in three cases. RESULTS: Of 11 women diagnosed with DCIS with spindle cells, four presented with nipple discharge, six with a breast lump, while one was discovered to have a screen detected density. The tumour size ranged from 3 to 41 mm. The proportion of spindle cells varied from 10% to 80% of the in-situ tumour cell population. Nuclear grade was low in seven cases and intermediate in four. Necrosis was observed in two cases. Architectural pattern was papillary in six cases, and mixed in the rest. Microinvasion was present in two cases, with possible microinvasion in another two. Immunohistochemistry for neuroendocrine markers synaptophysin and chromogranin showed positive reactivity for at least one marker in all but three cases; one of these latter cases demonstrated ultrastructural neurosecretory granules. Oestrogen and progesterone receptors were expressed in 10 and nine cases, respectively, while cerbB2 was positive in only one case. HMW cytokeratin immunoprofile revealed a general lack of immunostaining within the abnormal cell population; likewise, no positivity for SMA of the cellular proliferation was detected. CONCLUSIONS: Almost all DCIS lesions with spindle cells disclose neuroendocrine differentiation. Although the distinction from benign florid usual hyperplasia may pose a diagnostic histological problem, the presence of diffuse neuroendocrine expression, in conjunction with the pattern of HMW keratin profile on immunohistochemistry, supports an in-situ neoplastic process. The absence of SMA immunostaining, in conjunction with negative reactivity for cytokeratins 5/6 and 14, makes the possibility of a myoepithelial proliferation unlikely. 相似文献
886.
Chen HY Lu Y Howard T Anderson D Fong PY Hu WP Chia CP Guan M 《Clinical and diagnostic laboratory immunology》2005,12(5):593-598
An immunochromatographic test for rapid detection of IgM antibodies in patients with acute hepatitis E infection was developed utilizing the well-characterized recombinant protein EP2.1 and monoclonal antibody 4B2. The new rapid test based on a novel reverse-flow technology was able to generate a positive result within 2 to 3 min. Our study showed that this test was able to detect anti-HEV IgM antibodies in 96.7% of the patient samples tested (n = 151) while maintaining an excellent specificity of 98.6% with samples from various patient or healthy control groups (total n = 208). Furthermore, this rapid test gave a good specificity of 90.9% when tested with rheumatoid factor (RF)-positive sera (RF value of < or =850 IU/ml; n = 11) although a higher concentration of RF in samples might cause cross-reactivity. The new test has a good agreement of 97.2% with a kappa value of 0.943 when compared with a reference enzyme-linked immunosorbent assay. The positive predictive value and the negative predictive value for the rapid test thus reached 98.0 and 97.6%, respectively. This is the first rapid, point-of-care test for hepatitis E and will be especially useful for the diagnosis of acute hepatitis E virus infection in field and emergency settings and in resource-poor countries. 相似文献