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排序方式: 共有714条查询结果,搜索用时 15 毫秒
81.
82.
Riyaz Bhikoo MBChB Rachael L Niederer PhD MBChB Richard Hart FRANZCO Trevor Sherwin PhD Charles NJ McGhee PhD FRCS FRANZCO 《Clinical & experimental optometry》2013,96(4):430-432
We describe the corneal microstructural changes in a patient with spheroidal degeneration using in vivo confocal microscopy. Multiple hypo‐ and hyper‐reflective spherical lesions were observed in the anterior corneal stroma and Bowman's layer ranging from 45 to 220 μm in size. The corneal epithelium, posterior stroma and endothelium were otherwise unaffected. In vivo confocal microscopy demonstrates good correlation with excised histological samples in climatic droplet keratopathy. It provides a non‐invasive technique to examine the living cornea for degenerative disease and acts as a bridge between clinical and laboratory observations. 相似文献
83.
Christina N Grupcheva MD Jennifer P Craig PhD Trevor Sherwin PhD Charles NJ McGhee PhD FRCOphth FRACO 《Clinical & experimental ophthalmology》2001,29(3):133-137
The purpose of this study was to demonstrate microstructural differences between clinically similar, but aetiologically different, cases of corneal oedema in four subjects. In vivo confocal microscopy highlighted oedema of the basal epithelium, prominent nerve–keratocyte interactions, and typical ‘epithelialization’ of the endothelium in a case of iridocorneal endothelial syndrome; however, a similar microstructural appearance was observed in a case of presumed herpetic disciform keratitis. The latter diagnosis was subsequently revised on this basis. Confocal examination of Fuchs’ endothelial dystrophy demonstrated oedema of the basal epithelium, prominent wing cells, anterior stromal alterations, fibrosis of Descemet’s membrane and a typical ‘strawberry’ appearance of the endothelium. In contrast, in vivo microstructural examination of bilateral keratoconus with hydrops confirmed oedema mainly involving the epithelium and anterior stroma. In vivo confocal microscopy allows the clinician to observe the living cornea at a microstructural level and to better diagnose and differentiate borderline or unusual cases of corneal oedema. 相似文献
84.
S. K. BRÆKKAN E. B. MATHIESEN I. NJØLSTAD T. WILSGAARD J. STØRMER J. B. HANSEN 《Journal of thrombosis and haemostasis》2008,6(11):1851-1857
Summary. Background: Recent studies indicate that arterial cardiovascular diseases and venous thromboembolism (VTE) share common risk factors. A family history of myocardial infarction (MI) is a strong and independent risk factor for future MI. Objectives: The purpose of the present study was to determine the impact of cardiovascular risk factors, including family history of MI, on the incidence of VTE in a prospective, population‐based study. Patients and methods: Traditional cardiovascular risk factors and family history of MI were registered in 21 330 subjects, aged 25–96 years, enrolled in the Tromsø study in 1994–95. First‐lifetime VTE events during follow‐up were registered up to 1 September 2007. Results: There were 327 VTE events (1.40 per 1000 person‐years), 138 (42%) unprovoked, during a mean of 10.9 years of follow‐up. In age‐ and gender‐adjusted analysis, age [hazard ratio (HR) per decade, 1.97; 95% confidence interval (CI), 1.82–2.12], gender (men vs. women; HR, 1.25; 95% CI, 1.01–1.55), body mass index (BMI; HR per 3 kg m?2, 1.21; 95% CI, 1.13–1.31), and family history of MI (HR, 1.31; 95% CI, 1.04–1.65) were significantly associated with VTE. Family history of MI remained a significant risk factor for total VTE (HR, 1.27; 95% CI, 1.01–1.60) and unprovoked VTE (HR, 1.46; 95% CI, 1.03–2.07) in multivariable analysis. Blood pressure, total cholesterol, HDL‐cholesterol, triglycerides, and smoking were not independently associated with total VTE. Conclusions: Family history of MI is a risk factor for both MI and VTE, and provides further evidence of a link between venous and arterial thrombosis. 相似文献
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87.
Goulding SM Leiner AS Thompson NJ Weiss PS Kaslow NJ Compton MT 《Early intervention in psychiatry》2008,2(3):162-168
Aim: Evidence suggests that treatment delay, represented by the duration of untreated illness (DUI) and the duration of untreated psychosis (DUP), may be a potentially powerful determinant of the early course of primary psychotic disorders. Yet, research on the predictors of treatment delay has only just begun. To date, there are virtually no empirical data on the relationship between family functioning and treatment delay in the context of first‐episode psychosis. In this study, it was hypothesized that family strengths would be inversely correlated with DUI and DUP; and families of patients with a short DUI/DUP would have greater family strengths than those of patients with a long DUI/DUP. Methods: Family strengths (including pride and accord dimensions), DUI and DUP were assessed in 34 African Americans hospitalized for first‐episode psychosis and their respective 34 family members most involved in initiating care. Results: The total score of the Family Strengths scale and the accord subscale score were significantly inversely correlated with both DUI and DUP, although the correlation between the pride subscale score and DUI/DUP was not as strong and failed to reach statistical significance. Similarly, the family members of patients with a short DUI/DUP had higher family strength scores than those of patients with a long DUI/DUP. Conclusions: Given the dearth of research on the functioning of families beginning to initiate care for individuals with first‐episode psychosis, it is imperative to further clarify the role family characteristics may play in understanding treatment delay (DUI/DUP) and in the development of preventive interventions to facilitate early intervention for at‐risk populations. 相似文献
88.
Hall RM; Unsworth A; Wroblewski BM; Siney P; Powell NJ 《Rheumatology (Oxford, England)》1997,36(1):20-26
Charnley prostheses, retrieved at revision surgery, were studied to assess
the effects of friction on the total hip replacement procedure. Frictional
resistance was measured using the Durham hip function simulator under both
dry and lubricated conditions. The friction factor values (f) for the
explanted prostheses were found to have a non- Gaussian distribution with
medians of 0.13 [inter-quartile range (IQR) 0.10-0.16] and 0.06 (IQR
0.005-0.08) for dry and lubricated (n = 0.01 Pa s) regimes, respectively.
New Charnley prostheses had values of f equal to 0.11 +/- 0.025 and 0.04
+/- 0.01 under the same conditions, and showed no large deviation from a
Gaussian distribution. There was found to be a statistically significant
difference in the medians of the friction factors for new and retrieved
prostheses in the lubricated regime. Ingression of cement into the worn
region of the cup was found to increase the friction factor significantly
under dry conditions. There was no evidence of an increase in the friction
factor or torque for those joints that had a loose socket with respect to
those that were fixed at revision. A decrease in the frictional torque
against number of cycles undergone by the joint in vivo may indicate that a
fatigue-type process may have a role in the loosening of the socket.
However, this relationship was found not to be significant for friction
measured under lubricated conditions and it seems unlikely that the
frictional torque generated in this type of prosthesis will contribute
significantly to the long-term loosening of the socket.
相似文献
89.
90.
R A Kaslow J P Phair H B Friedman D Lyter R E Solomon J Dudley B F Polk W Blackwelder 《Annals of internal medicine》1987,107(4):474-480
In 1984 a large prospective study of gay and bisexual men was begun to elucidate the natural history of the human immunodeficiency virus (HIV) infection. At two successive semiannual examinations, clinical or hematologic abnormalities were found up to 13 times more often among HIV-seropositive men (n = 1611) than HIV-seronegative men (n = 2646). More than 30% of the seropositive participants had persistent generalized lymphadenopathy, independent of T-helper lymphocyte (CD4) counts and most other signs and symptoms. Other clinical manifestations such as thrush, anemia, thrombocytopenia, neutropenia, fever, and fatigue occurred with only slightly reduced CD4 counts (400 to 700/mm3) and appeared to increase exponentially with progressively lower counts. A simple systematically derived clinical index using these manifestations identified more than 70% of the seropositive men with significant T-helper cell depletion. This kind of clinical index may be useful for assessing groups of HIV-infected persons, especially those whose T-lymphocyte numbers and function cannot be readily measured. 相似文献