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61.
Atypical meningioma spreading via the perivascular spaces 总被引:2,自引:0,他引:2
62.
The association between APOE and dementia does not seem to be mediated by vascular factors 总被引:7,自引:0,他引:7
OBJECTIVE: The effect of APOE on dementia may be mediated through dyslipidemia and atherogenesis through its effect on cholesterol metabolism. The authors investigated this possibility among aged survivors from the UK Medical Research Council Trial of the Treatment of Hypertension in Older Adults. DESIGN: A total of 370 of 657 survivors from an initial cohort of 1,088 recruited into the trial between 1983 and 1985 were traced in 1994 and agreed to be screened for dementia. Blood samples were analyzed for APOE genotype and serum fibrinogen. Cholesterol level, smoking behavior, blood pressure, body mass index, and EKG recordings had been measured at recruitment 10 to 12 years earlier. Odds ratios (ORs) for the association between APOE epsilon4/* and both AD and dementia were estimated and adjusted incrementally for the effect of age and premorbid intelligence, cholesterol, other risk factors for vascular disease, and EKG evidence of cardiovascular disease. RESULTS: The authors diagnosed 24 cases of National Institute of Neurological and Communicative Disorders and Stroke AD from 41 cases of dementia. The crude OR for the association between APOE epsilon4/* and AD was 3.40 (95% CI 1.30 to 8.91). APOE genotype was associated with serum cholesterol level, and there was a nonsignificant trend for an association with smoking behavior. After adjusting for these and all other vascular risk factors and vascular disease variables listed earlier, the OR for the association between APOE epsilon4/* and AD increased to 4.81 (1.60 to 14.4). CONCLUSION: Presence of APOE epsilon4/* seems to increase the risk for dementia and AD independently of its effect on dyslipidemia and atherogenesis. 相似文献
63.
Thromboembolic disease: variability of interobserver agreement in the interpretation of CT venography with CT pulmonary angiography 总被引:7,自引:0,他引:7
OBJECTIVE: The objective of this study was to determine interobserver agreement in the diagnosis of acute deep venous thrombosis on CT venography performed in addition to CT pulmonary angiography. SUBJECTS AND METHODS: One hundred forty-six CT venograms of 144 patients (mean age, 61.74 years) clinically suspected of having pulmonary embolism were analyzed prospectively and independently by two experienced thoracic and body imaging radiologists and later by consensus of the two radiologists. The CT venography protocol consisted of 5-mm-thick axial images at 20-mm intervals from the popliteal fossa to the renal veins. Images were acquired 3-4 min after the start of 100-150 mL of undiluted contrast medium administration at 4 mL/sec. Thirteen venous segments were analyzed in each patient. There were 1586 analyzable venous segments. RESULTS: Interobserver agreement, with the patient as the unit of analysis, was moderately good (kappa, 0.59; 95% confidence interval [CI], 0.39-0.78). Kappa values were similar for CT venography studies performed with 150 mL of contrast medium and 4-min delay (kappa, 0.62; 95% CI, 0.30-0.88) and with 3-min delay and 100 mL of contrast medium (kappa, 0.56; 95% CI, 0.32-0.80). Interobserver disagreement occurred in 17 (12%) of 146 CT venography studies. Findings of 11 CT venography studies were interpreted as negative, and six were interpreted as positive after consensus interpretation. CONCLUSION: Interobserver agreement for deep venous thrombosis with CT venography is moderately good. 相似文献
64.
A complete remission of widely metastatic bladder carcinoma was obtained with chemotherapy in a 41-year-old man. Severe persistent anorexia led to a 33% weight loss. The anorexia correlated with an elevated sucrose recognition threshold. Following 16 days of intravenous hyperalimentation, taste sensation returned to normal, anorectic symptoms cleared, and weight gain and positive nitrogen balance resulted. There was no stimulation of tumor growth. Restoration of nutritional deficits with intravenous hyperalimentation can improve taste function and appetite so that adequate oral alimentation can be tolerated. 相似文献
65.
Increasingly, in the United States, lives are being extended at ever-older ages through the implementation of routine medical procedures such as renal dialysis. This paper discusses the lives and experiences of a number of individuals 70 years of age and older at two dialysis units in California. It considers what kind of life it is that is being sustained and prolonged in these units, the meanings of the time gained through (and lost to) dialysis for older people, and the relationship of "normal" life outside the units to an exceptional state on the inside that some patients see as not-quite-life. Highlighting the unique dimensions of gerontological time on chronic life support, the article offers a phenomenology of the end of life as that end is drawn out, deferred by technological means, and effaced by the ethos and experiential course of dialysis treatment. 相似文献
66.
William H. Heydorn Russ Zajtchuk John Miller George F. Schuchmann 《The Annals of thoracic surgery》1977,23(6):539-544
In an effort to evaluate polytetrafluoro-ethylene (Gore-Tex) as a replacement for large veins, tubular grafts of the material were substituted for the precava in 33 mongrel dogs weighing 15 to 30 kg. Thirteen dogs had grafts 10 cm long by 12 mm wide with a 15- to 30-u pore size; 15 dogs had grafts of the same length and width from 90-μ. pore size material; and 5 dogs had grafts 5 cm long by 12 mm wide, of 90-μ pore size Gore-Tex. The effect of Gore-Tex tubes with and without spiral support and the differences in anatomical positions of the grafts were evaluated in terms of patency. Dogs were killed if a venogram showed occlusion of the graft. Twelve dogs survived 90 days; the longest survivor was killed at eleven months. At postmortem examination, the graft was patent but extremely narrow at the atrial end. Modification in the fabrication of Gore-Tex may eliminate factors contributing to graft failure; experiments longer than 90 days are necessary to evaluate Gore-Tex as a large vein replacement material. The 90-μ pore size material used in this experiment was unsuitable as a canine venous substitute. 相似文献
67.
Evidence of oxidative stress in full-term healthy infants 总被引:5,自引:0,他引:5
We hypothesized that early infancy would be a time of oxidative stress due to the difficulty of adapting to ambient oxygen. Therefore, we measured levels of products of lipid peroxidation (F2-isoprostanes), antioxidant enzyme activity (catalase (CAT) and superoxide dismutase (SOD)), and ability to resist oxidative stress (ferric reducing ability of plasma (FRAP)) in full-term infants (38-42 wk) fed human milk from birth. Seventy-seven infants were followed at 1, 3.5, 6, and 12 mo of age. F2-isoprostanes in plasma declined significantly (p < 0.05) from 1 to 6 mo (160 +/- 43; 90 +/- 33; 41 +/- 27 pg/mL (mean +/- SD)). FRAP values (775 +/- 196, 723 +/- 133, 697 +/- 126, 669 +/- 145 microM) 1, 3.5, 6, and 12, respectively) declined (p = 0.06) from 1 to 3.5 mo and from 3.5 to 6 mo of age. RBC-SOD (2.7 +/- 2, 3.2 +/- 2.8, 2.1 +/- 1.8, 2.5 +/- 1.8 U, 1, 3.5, 6, 12 mo, respectively) declined from 3.5 to 6 mo. RBC-CAT (76 +/- 23, 94 +/- 28, 81 +/- 22, 85 +/- 31 U, 1, 3.5, 6, 12 mo, respectively) also declined between 3.5 and 6 mo, after a significant increase between 1 and 3.5 mo. These data suggest that the human infant is under oxidative stress early in infancy and further study may be warranted to assess the potential benefits of antioxidant supplementation for either the mother or the infant. 相似文献
68.
69.
Zusammenfassung Die hämatogene Osteomyelitis (HOM) bei Erwachsenen ist in industrialisierten Ländern äußerst selten. Dahingegen dürfte die Morbidität in tropischen Klimazonen deutlich höher liegen, begünstigt u. a. durch Hämoglobinopathien wie Sichelzellenanämie und Thalassämie, durch die HIV-Pandemie und Tuberkulose. Pathogenetisch werden bakterielle—unspezifische und spezifische (Tb, Syphilis, Sarkoidose)—von abakteriellen Formen der HOM unterschieden (plasmazelluläre OM, sklerosierende OM, SAPHO-Syndrom). HOM durch atypische Erreger (Pilze, Viren, Parasiten) sind trotz ihrer Seltenheit differenzialdiagnostisch ebenso zu berücksichtigen wie Knochenveränderungen durch benigne und maligne Neoplasien (Ewing-Sarkom, Osteosarkom, Knochenlymphom u. a. m.). Epidemiologie und Pathologie der HOM mit Erregerspektrum, Quellgebieten, bahnenden Kofaktoren und pathomorphologischen Veränderungen werden ausführlich dargestellt, ebenso wie das aktuelle diagnostische und therapeutische Procedere. 相似文献
70.
BACKGROUND: Intracranial dural arteriovenous fistulas account for 10 to 15% of all intracranial arteriovenous malformations. Tentorial dural arteriovenous fistulas with spinal medullary venous drainage causing spinal cord myelopathy are very rare, but have been previously described. We describe a case using a cranio-orbito zygomatic approach with intraoperative angiography for the surgical treatment of a tentorial artery dural arteriovenous fistula causing spinal cord myelopathy. CASE PRESENTATION: A 42-year-old male presented complaining of a 1-year history of incoordination and dizziness and a 2-month history of progressive myelopathy with bowel and bladder incontinence. The patient had magnetic resonance imaging (MRI) performed along with cerebral and spinal angiography that revealed a right tentorial artery dural arteriovenous fistula with spinal medullary venous involvement down to T11. Angiographic embolization was attempted, but selective catheterization was unsuccessful. The patient underwent a cranio-orbito zygomatic approach with obliteration of the dural arteriovenous fistula. An intraoperative angiogram confirmed complete obliteration of the dural arteriovenous fistula. CONCLUSION: Intracranial dural arteriovenous fistulas are a rare cause of spinal cord myelopathy. When a patient presents with suspicion of spinal dural fistula and negative spinal angiography, an intracranial origin should be suspected and a cerebral angiogram performed. Skull base approaches along with intraoperative angiography provide an alternative modality for obliteration of the dural arteriovenous fistula nidus, thereby eliminating the venous congestion and hence the spinal cord ischemia. 相似文献