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61.
The influence of operative technique on the formation of incomplete cement mantles in the sagittal plane has been rarely considered in the literature. In this article, we discuss the influence of the anatomy of the proximal femur on the formation of incomplete cement mantles and discuss how their incidence can be reduced by correct component positioning. 相似文献
62.
Meyer JS Rauch GM Crawford K Rauch RA Konno S Akiyama H Terayama Y Haque A 《International journal of geriatric psychiatry》1999,14(12):1050-1061
OBJECTIVES: Factors accelerating cerebral degenerative changes represent potentially modifiable risks for cognitive decline. Putative risk factors accelerating subtle cognitive decline and dementia were correlated with repeated measures of cerebral atrophy, CT densitometry, perfusions and cognitive testing among neurologically and cognitively normative ageing volunteers. METHODS: Two hundred and twenty-four normative subjects at increased risk for cognitive decline were admitted to the study. Mean entry age was 59. 5+/-15.8 years. Mean follow-up is 4.3+/-3.1 years. At follow-up, 22 developed subtle cognitive decline (deltaCCSE>/=-3), 19 became demented, eight with vascular type (VAD) and 11 with Alzheimer's type (DAT) and 183 remain cognitively unchanged. Standardized questionnaires, medical, neuropsychological, neurological and blood work examinations were obtained. Cerebral atrophy, tissue densities and perfusions were measured by xenon-enhanced CT. RESULTS: After age 60, cerebral atrophy, ventricular enlargement, polio- and leuko-araiosis geometrically increased as perfusions declined. Risk factors accelerating perfusional decline, cerebral atrophy, polio-araiosis and leuko-araiosis (thinning of grey-white matter densities) were: transient ischaemic attacks (TIAs), hypertension, smoking, hyperlipidemia, male gender. At age 71.5+/-11.9, subtle cognitive decline began, accelerated by TIAs, hypertension and heart disease. Leuko-araiosis began before cognitive decline. TIAs, hypertension and hyperlipidemia correlated with VAD. Excessive cortical perfusional decreases and cerebral atrophy correlated with cognitive decline. Family history of neurodegenerative disease correlated with DAT. CONCLUSION: TIAs, hypertension, hyperlipidemia, smoking and male gender accelerate cerebral degenerative changes, cognitive decline and dementia. 相似文献
63.
BACKGROUND: The purpose of this study was to examine the diagnostic efficiency of prostate-specific antigen (PSA) and digital rectal examination (DRE) testing when using either 4.0 ng/ml or an age-specific reference range (ASRR) as an abnormal cutoff PSA value. METHODS: Between 1992-1995, 116,073 men, aged 40-79 years, were screened during Prostate Cancer Awareness Week. When using a 4.0-ng/ml cutoff PSA value, 22,014 had either an abnormal PSA, an abnormal DRE, or both. When using an ASRR cutoff PSA value, 17,561 had either an abnormal PSA, an abnormal DRE, or both. The positive predictive value (PPV), sensitivity, and specificity of PSA, DRE, and combined PSA and DRE tests were evaluated. RESULTS: When using a 4.0-ng/ml cutoff PSA value, the PPVs of abnormal PSA alone, abnormal DRE alone, and combined abnormal PSA and DRE tests were 27.7%, 17.7%, and 56.0%, respectively. Sensitivities were 34.9%, 27.1%, and 38.0%, respectively. Specificities were 63.1%, 49.0%, and 87.9%, respectively. When using an ASRR cutoff PSA value, the PPVs of each category were 31.8%, 20.8%, and 63.7%, respectively. Sensitivities were 27.1%, 41.0%, and 31.8%, respectively. Specificities were 75.0%, 32.8%, and 92.2%, respectively. The PPVs of the PSA test were higher than those of the DRE. The PPVs of combined tests were highest when using either a 4.0-ng/ml cutoff PSA value or an ASRR cutoff PSA value (all P < 0.001). When using an ASRR, the PPVs of PSA, DRE, and combined tests were higher than those when using a 4.0-ng/ml without statistical significance (all P > 0.05). Sensitivity of PSA when using an ASRR was lower than when using 4.0 ng/ml. CONCLUSIONS: Significantly higher PPVs indicated that utilizing both a PSA test and a DRE is most effective in screening for the early detection of prostate cancer. Although higher PPVs when using an ASRR cutoff PSA value suggested fewer unnecessary biopsies, lower sensitivities resulted in fewer cancers detected. Thus, we recommend that the combination of a PSA test with a cutoff value of 4.0 ng/ml and a DRE should continue to be utilized in the screening programs. 相似文献
64.
Crawford R Puddle B Hunt N Athanasou NA 《The Journal of bone and joint surgery. British volume》1999,81(3):552-554
We reviewed histologically the incidence and pathogenesis of the deposition of calcium pyrophosphate dihydrate (CPPD) crystals in the pseudocapsule, femoral and acetabular membranes and periprosthetic tissue at revision of 789 cases of failed total hip replacement. In 13, periprosthetic tissues were found to have deposits of CPPD crystals in areas of cartilaginous metaplasia; four also showed evidence of localised deposition of amyloid. None of the patients had a history of chondrocalcinosis in the hip or other joints. Cartilaginous metaplasia and other changes in periprosthetic tissues may predispose to the deposition of CPPD and associated localised amyloid. 相似文献
65.
Exposure of expanded polytetrafluoroethylene-wrapped hydroxyapatite orbital implant: a report of two patients 总被引:2,自引:0,他引:2
Choo PH Carter SR Crawford JB Seiff SR 《Ophthalmic plastic and reconstructive surgery》1999,15(2):77-78
PURPOSE: Hydroxyapatite (HA) spheres used to replace volume after an enucleation are often wrapped with autologous tissue before orbital implantation. Man-made materials are less expensive and pose no risk for viral transmission. The use of expanded polytetrafluoroethylene (ePTFE) to wrap HA spheres was evaluated. METHODS: The medical records of 2 consecutive patients who underwent uncomplicated implantation of an HA sphere wrapped in ePTFE were reviewed. RESULTS: An unusual reaction to the ePTFE material that was nonresponsive to topical or systemic antibiotic therapy developed in these 2 patients. Eventual wound erosion and bacterial infection of the implant necessitated its removal. CONCLUSIONS: Although well tolerated in other surgeries, ePTFE, when used to wrap HA spheres and placed into the orbit, may cause persistent conjunctival discharge, pyogenic granuloma formation, and eventual wound erosion. Therefore, the use of this material to wrap HA spheres is not recommended. 相似文献
66.
C R Hicks A B Clayton S Vijayasekaran G J Crawford T V Chirila I J Constable 《Ophthalmic plastic and reconstructive surgery》1999,15(5):326-332
PURPOSE: To develop a poly(2-hydroxyethyl methacrylate) orbital implant that allows tissue ingrowth and direct muscle attachment to minimize the risk of extrusion and to enhance cosmesis. METHODS: Assessment of clinical outcomes and histologic findings after implantation of 18 prototype prostheses into rabbits. The implants were not wrapped with other tissues or materials. RESULTS: One case of infection was observed but there were no extrusions, with up to 21 months follow-up. Biocolonization was confirmed histologically. Good movement was observed when a cosmetic shell was fitted. CONCLUSIONS: The prototype prosthesis appears promising, with particular advantages being the direct attachment of extraocular muscles, good cosmesis and movement, and a low complication rate in this pilot study. 相似文献
67.
Runnegar M Seward DJ Ballatori N Crawford JM Boyer JL 《Toxicology and applied pharmacology》1999,161(1):40-49
Microcystin-induced ser/thr protein phosphatase (PP) inhibition and toxicity were examined in the little skate (Raja erinacea), an evolutionarily primitive marine vertebrate. As in mammals, PP inhibition and toxicity were exclusively hepatocellular, but were much more persistent in the skate. A dose of 63 microg/kg given iv to adult male skates resulted in the near complete inhibition of hepatic PP activity at 24 h. PP activity was still 95% inhibited 7 days after dosing in skates given 125 microg/kg microcystin. Mortality occurred at doses of 500 microg/kg or more. Hepatic lesions were only seen in animals with fully inhibited PP activity in liver. The histological changes seen at 125 microg/kg were mild periportal inflammatory changes increasing in severity together with hepatocyte necrosis at higher doses of microcystin. Microcystin persisted and could be detected in plasma up to 7 days after dosing. This finding shows that, in the skate, as in mammals, the liver is the only organ capable of uptake of microcystin, since there was no significant inhibition of PP activity in the rectal gland and small decreases in PP activity of the kidney that were not time or dose dependent. In vitro microcystin caused dose-dependent inhibition of PP activity in isolated skate hepatocytes, while it was without effect in cultured rectal glands. Uptake of microcystin and the accompanying inhibition of PP activity in skate hepatocytes was prevented by the addition of a series of organic dyes and bile acids. The spectrum of inhibitors of microcystin uptake in skate is similar to that seen in the rat, indicating common features of the carrier(s) in these diverse species. 相似文献
68.
Marshall ME Wolf M O'Rourke M Barnett TC Crawford ED 《Cancer biotherapy & radiopharmaceuticals》1996,11(2):119-123
Based upon prior data suggesting that alpha-interferon possesses chemomodulatory activity, the Southwest Oncology Group conducted a study in which patients with hormone refractory, metastatic (stage D2) adenocarcinoma of the prostate were treated with 5-fluorouracil (5-FU) and Roferon-A. All patients had bidimensionally measurable disease. Treatment consisted of 5-FU 750 mg/m2/day by continuous i.v. infusion for 5 days with Roferon-A 9 million units subcutaneously ono days 1, 3 and 5. Roferon-A was continued three times weekly throughout treatment. Following a one week hiatus from 5-FU (week 2), 5-FU was continued at a dose of 750 mg/m2 i.v. bolus weekly. Nineteen patients were evaluable for toxicity. The most common toxicities were gastrointestinal and mucosal, hematologic and a flu-like syndrome. There were no deaths related to treatment. Among the 14 patients evaluable for response, the response rate was 0% (95% confidence interval, 0-18%). Thirteen of the 19 evaluable patients have died with a median survival of 9 months. The combination of 5-FU and Roferon-A does not have sufficient activity against advanced, hormone refractory prostate cancer to warrant further investigation. 相似文献
69.
70.
Devere White RW Deitch AD Tesluk H Blumensteinj B Lowe BA Sagalowsky AI Smith JA Schellhammer PF Stanisic TH Grossman HB Messing E Crissman JD Crawford ED 《Urologic oncology》1996,2(1):27-34
While 80% of transitional cell carcinomas (TCC) present as Ta Tl lesions, they account for only 15% of deaths caused by TCC. We have evaluated the ability of DNA ploidy analysis to predict outcome in 228 patients with Ta Tl TCC. All patients were judged to be at increased risk for tumor recurrence due to having two occurrences of Stage TI tumor within 56 weeks, or three or more tumors presenting simultaneously within 16 weeks of registration. Concurrent carcinoma in situ was acceptable. All patients were treated with either bacillus Calmette Guerin (BCG) immunotherapy or mitomycin-C (MMC) intravesical chemotherapy. Patients with nondiploid tumors had higher hazard rates for both tumor progression and death (p = 0.007 and p = 0.016, respectively); however, the prognostic information of DNA ploidy was not additive to tumor grade. 相似文献