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1.
Ian A. Chisholm Stephen M. Drance Teresa To 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1989,227(2):110-113
Visual-field areas to a I2e stimulus were measured planimetrically using an X-Y digitizer and a computer program. Sampling of normal subjects and patients suspected of having glaucoma was done at two points in time. Calculations of eye-wall stress were done using ultrasonic data and intra-ocular pressure (IOP) measurements from patient records. For those suspected of having glaucoma who developed chronic open-angle glaucoma (COAG), the time of transition was the second point in time. The visual field area was regressed against patient age at the two points in time. No difference in the regression slopes was found for the normal subjects and unchanged patients. The patients who did develop glaucoma were significantly different. The mean annual rate of visual-field change (rate of decay) was calculated and found to be 28.5 mm2/year for the normals, 153.5 mm2/year for the suspects, and 376.4 mm2/year for those patients who developed glaucoma. The rate of visual-field decay only correlated with patient age (P = 0.03) and eye-wall stress (P < 0.01) in the patients who developed glaucoma. 相似文献
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3.
Pulmonary pathological features in coronavirus associated severe acute respiratory syndrome (SARS) 总被引:5,自引:0,他引:5
Tse GM To KF Chan PK Lo AW Ng KC Wu A Lee N Wong HC Mak SM Chan KF Hui DS Sung JJ Ng HK 《Journal of clinical pathology》2004,57(3):260-265
BACKGROUND: Severe acute respiratory syndrome (SARS) became a worldwide outbreak with a mortality of 9.2%. This new human emergent infectious disease is dominated by severe lower respiratory illness and is aetiologically linked to a new coronavirus (SARS-CoV). METHODS: Pulmonary pathology and clinical correlates were investigated in seven patients who died of SARS in whom there was a strong epidemiological link. Investigations include a review of clinical features, morphological assessment, histochemical and immunohistochemical stainings, ultrastructural study, and virological investigations in postmortem tissue. RESULTS: Positive viral culture for coronavirus was detected in most premortem nasopharyngeal aspirate specimens (five of six) and postmortem lung tissues (two of seven). Viral particles, consistent with coronavirus, could be detected in lung pneumocytes in most of the patients. These features suggested that pneumocytes are probably the primary target of infection. The pathological features were dominated by diffuse alveolar damage, with the presence of multinucleated pneumocytes. Fibrogranulation tissue proliferation in small airways and airspaces (bronchiolitis obliterans organising pneumonia-like lesions) in subpleural locations was also seen in some patients. CONCLUSIONS: Viable SARS-CoV could be isolated from postmortem tissues. Postmortem examination allows tissue to be sampled for virological investigations and ultrastructural examination, and when coupled with the appropriate lung morphological changes, is valuable to confirm the diagnosis of SARS-CoV, particularly in clinically unapparent or suspicious but unconfirmed cases. 相似文献
4.
Case report: human herpesvirus 7 associated fatal encephalitis in a peripheral blood stem cell transplant recipient 总被引:2,自引:0,他引:2
Chan PK Chik KW To KF Li CK Shing MM Ng KC Yuen PM Cheng AF 《Journal of medical virology》2002,66(4):493-496
Previous studies have suggested a neuroinvasive and neuropersistent potential of human herpesvirus 7 (HHV-7). In this report, a case of fatal encephalitis is described and its association with HHV-7 infection is discussed. An 8-year-old girl received a peripheral blood stem cell transplant for relapsed acute lymphoblastic leukaemia. The post-transplant period was uneventful and a course of intrathecal chemotherapy was given on Day-30. On Day-41, she developed acute encephalopathy with diplopia and nystagmus. She ran a rapid downhill course and succumbed despite antiviral treatment. The only positive pathological finding was the multiple microscopic foci of haemorrhage associated with neuronal degeneration detected in the brain stem. All microbiological investigations were negative, except for the presence of HHV-7 DNA in cerebrospinal fluid and brain stem tissue samples. 相似文献
5.
Development and characterization of a whole-cell radioligand binding assay for [125I]gp120 of HIV-1.
L P To V Balasubramanian M E Charlton T A Francis C Doyle P M Sweetnam 《Journal of immunoassay》1992,13(1):61-83
The binding of HIV-1 envelope glycoprotein, gp120, to the CD4 receptor is an important step in productive infection. The development of agents which interrupt this binding phenomenon should be of therapeutic interest. The present study characterizes a whole cell gp120/CD4 radioligand binding assay (radioligand binding assay) modified for use in a high volume screening format. Modifications include the use of human CD4 receptor stably expressed in a Chinese hamster ovary cell line and the gentle fixation (paraformaldehyde) of the CD4 receptor just prior to assay. Binding of [125I]gp120 to fixed CD4 was of high affinity (KD = 6 nM), saturable, reversible, and specific. The kinetics of binding were identical to those of viable (non-fixed) CD4 receptor. [125I]gp120 binding was inhibited by unlabeled recombinant gp120, soluble CD4, and the anti-CD4 monoclonals OKT4A and LEU3A. A number of compounds reported to inhibit gp120 binding and/or gp120 induced syncytium formation were also active in this assay. This modified radioligand binding assay was developed to initiate a rational and extensive screening program to assist in the identification of potential chemotherapeutic agents based on their ability to inhibit gp120 binding to host cells. 相似文献
6.
Kenneth Siu-Sing Leung Timothy Ting-Leung Ng Alan Ka-Lun Wu Miranda Chong-Yee Yau Hiu-Yin Lao Ming-Pan Choi Kingsley King-Gee Tam Lam-Kwong Lee Barry Kin-Chung Wong Alex Yat Man Ho Kam-Tong Yip Kwok-Cheung Lung Raymond Wai-To Liu Eugene Yuk-Keung Tso Wai-Shing Leung Man-Chun Chan Yuk-Yung Ng Kit-Man Sin Kitty Sau-Chun Fung Sandy Ka-Yee Chau Wing-Kin To Tak-Lun Que David Ho-Keung Shum Shea Ping Yip Wing Cheong Yam Gilman Kit-Hang Siu 《Emerging infectious diseases》2021,27(1):196
Initial cases of coronavirus disease in Hong Kong were imported from mainland China. A dramatic increase in case numbers was seen in February 2020. Most case-patients had no recent travel history, suggesting the presence of transmission chains in the local community. We collected demographic, clinical, and epidemiologic data from 50 patients, who accounted for 53.8% of total reported case-patients as of February 28, 2020. We performed whole-genome sequencing to determine phylogenetic relationship and transmission dynamics of severe acute respiratory syndrome coronavirus 2 infections. By using phylogenetic analysis, we attributed the community outbreak to 2 lineages; 1 harbored a common mutation, Orf3a-G251V, and accounted for 88.0% of the cases in our study. The estimated time to the most recent common ancestor of local coronavirus disease outbreak was December 24, 2019, with an evolutionary rate of 3.04 × 10−3 substitutions/site/year. The reproduction number was 1.84, indicating ongoing community spread. 相似文献
7.
Development and evaluation of a new composite Laserskin graft 总被引:5,自引:0,他引:5
BACKGROUND: Tremendous effort has been made to improve the graft take rate of cultured epidermal autograph. The purpose of this study is to develop and evaluate a new composite Laserskin graft (CLSG) as a human skin substitute for wound resurfacing. METHODS: The seeding efficacy of cultured keratinocytes on plain Laserskin was compared with the 3T3 cell-seeded Laserskin and allogenic fibroblast-populated Laserskin. Three different types of CLSG, 2 cm in diameter each, were prepared and tested in rats. Type A CLSG consisted of proliferative allogenic rat fibroblasts on both sides of the Laserskin with autologous keratinocytes also on the upper side. Fibroblasts and keratinocytes were seeded only on the upper side of the Laserskin in type B CLSG. Keratinocytes alone were seeded on plain Laserskin in type C CLSG. Type B CLSG consisting of autologous keratinocytes and autologous dermal fibroblasts was tested on five selected wounds (5x5 cm each) of a patient with full-thickness burn. In another burn patient, type B CLSG consisting of autologous keratinocytes and allogenic dermal fibroblasts was grafted onto three wounds (5x5 cm each). RESULTS: The seeding efficacy of human keratinocytes on plain Laserskin increased from 75% to 95% when proliferative allogenic fibroblasts were grown as a feeder layer on the Laserskin. The seeding efficacy of rat keratinocytes increased from 36% to 88% in the presence of a proliferative allogenic fibroblast feeder layer, whereas human/rat keratinocytes had respective seeding efficacy of 98%/91% on Laserskin preseeded with mitomycin C-treated 3T3 cells. Skin biopsies of grafted type A CLSG on day 14 after grafting showed complete epithelialization without severe inflammation in 16 of 20 (80%) grafted surgical wounds in rats. There were eight (40%) and seven (35%) "takes" of the CLSG in types B and C, respectively. The infection rate in type B CLSG was two (10%). There was one (5%) infection in types A and C. The respective take rates on the two patients grafted with type B CLSG were 60% and 100%. CONCLUSION: The animal experiment and the preliminary clinical data showed that the CSLGs consisting of autologous keratinocytes and of autologous/allogenic fibroblasts are good human skin substitutes in terms of durability, biocompatibility, high seeding efficacy for keratinocytes, high graft take rate, and low infection rate. 相似文献
8.
The preliminary studies on acidic degradation of heparin were performed. The UV-VIS and 1H-NMR techniques were used. The analogical features of degradation products of heparin, glucuronic acid and furfural were found (7 characteristic groups). 相似文献
9.
10.
Staging papillary carcinoma of the thyroid: magnetic resonance imaging vs ultrasound of the neck 总被引:6,自引:0,他引:6
AIM: To evaluate the role of magnetic resonance imaging (MRI) for staging local disease and lymph node metastases in papillary carcinoma of the thyroid by comparing MRI with ultrasound (US) of the neck. MATERIALS AND METHODS: Fourteen patients with papillary carcinoma underwent MRI and US. The images were prospectively reviewed for (1) identification of the primary lesion; (2) presence of multifocal thyroid disease; (3) extracapsular extension; (4) invasion into the trachea, oesophagus and major vessels; and (5) presence of lymph node metastases. Correlation was made with the surgical findings. RESULTS: The site of the primary lesion was correctly identified by US in 14 of 14 (100%) and by MRI in 13 of 14 (93%) of patients. Multifocal thyroid tumour was correctly identified by US in two of two patients (100%) and by MRI in zero of two (0%). Extracapsular extension (n = 9), oesophageal invasion (n = 1) and tracheal invasion (n = 2) were identified by MRI in seven, zero, and one, and by US in six, zero and zero patients, respectively. Invasion of the major vessels was not seen. Metastatic cervical nodes were present in 19 nodal groups in 10 patients involving the internal jugular chain (n = 10), posterior triangle (n = 4) supraclavicular fossa (n = 1) and central group (n = 4). Both MRI and US failed to identify metastatic nodes in the central group but correctly identified 14 of the 15 nodal groups outside the central group. CONCLUSION: Ultrasound should be used as the first line of investigation for detecting the primary lesion, multifocal disease and cervical lymphadenopathy. In cases where the primary tumour is not surrounded by normal thyroid tissue MR imaging should be added to assess extracapsular spread, especially into the trachea. 相似文献