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排序方式: 共有586条查询结果,搜索用时 15 毫秒
41.
Centrilobular emphysema: CT-pathologic correlation 总被引:5,自引:0,他引:5
Foster WL Jr; Pratt PC; Roggli VL; Godwin JD; Halvorsen RA Jr; Putman CE 《Radiology》1986,159(1):27-32
Over a 5-year period, 25 patients who had undergone chest computed tomography (CT) died and were autopsied. Their lungs were fixed in the inflated state and were assessed for the presence and severity of centrilobular emphysema (CLE). Three radiologists independently evaluated the CT scans for nonperipheral low-attenuation areas, peripheral low-attenuation areas, pulmonary vascular pruning, pulmonary vascular distortion, and pulmonary density gradient. The CT criterion that best correlated with the presence and severity of CLE was the nonperipheral low-attenuation area. With this CT criterion, lung destruction was correctly identified in 13 of 15 cases. The absence of this criterion resulted in correct identification of eight of ten normal lungs. These preliminary data suggest that CLE can be reliably identified and quantified with current CT scanners. 相似文献
42.
Prostatic evaluation by transrectal sonography with histopathologic correlation: the echopenic appearance of early carcinoma 总被引:6,自引:0,他引:6
Fifty-two patients with clinical stage A and B carcinomas of the prostate were imaged by ultrasound (US) transrectally with a 5-MHz linear array transducer and transabdominally with a 3-MHz sector scanner prior to radical prostatectomy. The fresh specimens of 44 prostate glands were scanned in a water bath with a 5-MHz linear array transducer in multiple planes. In all cases, histopathologic correlation was obtained. Prostatic carcinoma presented as an echopenic lesion in 54% of the specimens, as a slightly hypoechoic area in 22%, and could not be identified in 24% because of its isoechoic characteristics. In contrast to many previous reports, no instance of echogenic cancer was observed. 相似文献
43.
Baker LL; Hajek PC; Burkhard TK; Dicapua L; Leopold GR; Hesselink JR; Mattrey RF 《Radiology》1987,163(1):89-92
High-resolution magnetic resonance (MR) imaging with a surface coil was utilized to evaluate the normal scrotum. Scrotal contents, spermatic canal, and inguinal regions were visualized within the same field of view. Differences in signal intensity in the testis, epididymis, tunica albuginea, fluid, fat, and spermatic cord allowed for clear delineation of these structures in detail. The high contrast and spatial resolution of MR imaging, coupled with the wide field of view and absence of ionizing radiation, make MR imaging well suited for evaluation of the scrotum. 相似文献
44.
Peptic ulcer and gastric carcinoma: diagnosis with biphasic radiography compared with fiberoptic endoscopy 总被引:1,自引:0,他引:1
Shaw PC; van Romunde LK; Griffioen G; Janssens AR; Kreuning J; Eilers GA 《Radiology》1987,163(1):39-42
The diagnostic value of biphasic radiographic examination of the stomach and duodenum was compared with that of fiberoptic endoscopy in a prospective, blinded study of 385 patients with dyspepsia. This investigation was directed at gastric malignancies and peptic ulcers. Methodologically there is no absolute standard for a study of this kind because histologic examination is useful for detection of cancer but inadequate for ulcers. As an alternative, kappa indexes and the sensitivity and specificity, as derived by Hui and Walter, were calculated and compared. For the detection of gastric carcinoma, radiographic and endoscopic findings had almost perfect agreement beyond chance. For gastric ulcers, radiography and endoscopy had substantial agreement, which became perfect if small ulcers (less than 5 mm) were excluded. For duodenal ulcers, radiography had a lower sensitivity than endoscopy; this disagreement disappeared if small ulcers were excluded. Both methods have equal merit; choice of the initial diagnostic procedure will therefore depend on cost, discomfort to the patient, and risk of complications. 相似文献
45.
Anthropomorphic radiologic phantoms 总被引:1,自引:0,他引:1
A technique is being developed for the design and fabrication of anthropomorphic phantoms for diagnostic x-ray imaging. Anatomic information extracted from actual patient radiographs is incorporated into the phantoms using computer image processing and computer-assisted machining methods. In this paper, the technique is described as applied to a breast phantom, and preliminary images that closely mimic human anatomy on radiographs are shown. 相似文献
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A microcapillary method utilizing phthalate esters or an ultracentrifuge method are both capable of separating autologous from homologous erythrocytes in polytransfused patients. The microcapillary technique which is readily adaptable to blood bank laboratories provides a previously unavailable method for defining blood group antigen typings in transfused patients. Such typings are of vital importance in the laboratory evaluation of transfused patients with multiple or weak blood group antibodies. 相似文献
49.
Total radical trapping antioxidant potential (TRAP) and exercise 总被引:1,自引:0,他引:1
Sharpe PC; Duly EB; MacAuley D; McCrum EE; Mulholland C; Stott G; Boreham CA; Kennedy G; Evans AE; Trinick TR 《QJM : monthly journal of the Association of Physicians》1996,89(3):223-228
The relationship between physical activity, physical fitness and total
radical trapping antioxidant potential (TRAP) was examined in the Northern
Ireland Health and Activity Survey. This was a cross-sectional population
study (n = 1600) using a two-stage probability sample of the population.
TRAP was calculated using the sum of the individual serum antioxidant
concentrations (urate, protein thiols, ascorbate, alpha tocopherol and
bilirubin) multiplied by their respective stoichiometric values. Physical
fitness was determined by estimation of VO2max by extrapolation from
submaximal oxygen uptake, and physical activity was recorded by
computer-assisted interview. Mean serum TRAP concentrations were
significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared
to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female
smokers had significantly lower TRAP values than non-smokers (males p <
0.0001, females p = 0.02). In females, there was a positive relationship of
TRAP with age (p < 0.001) and body mass index (p < 0.001) but a
negative relationship with physical fitness (p < 0.05). The known
beneficial effects of exercise and activity do not appear to be directly
mediated through increased antioxidant status.
相似文献
50.
HE Connor W Feniuk DT Beattie PC North AW Oxford DA Saynor PPA Humphrey 《Cephalalgia : an international journal of headache》1997,17(3):145-152
The biological profile of naratriptan (N-methyl-3-(1-methyl-4-piperidinyl)-1H-indole-5-ethane-sulphona-mide), a novel 5HT1B/1D receptor agonist, was investigated in a variety of experimental models of relevance to migraine. Naratriptan has high affinity for human recombinant 5HT1B and 5HT1D receptors (pKi = 8.70.03 and 8.30.1, respectively) and causes contractions of dog isolated basilar and middle cerebral artery (EC50 values of 0.11 and 0.07 M, respectively). Naratriptan causes small contractions of human isolated coronary arteries (EC50 value of 0.17 M; maximum contraction equivalent to 33% of 5HT maximum). In anaesthetized dogs, naratriptan causes selective vasoconstriction of the carotid arterial bed (CD50 dose = 193 g kg−1 ) and, in anaesthetized rats, naratriptan selectively inhibits neurogenic plasma protein extravasation in the dura (ID50 = 4.1 g kg−1 ). In a variety of antinociceptive tests, naratriptan has no effect even at high doses. In conscious rats and dogs, naratriptan has high oral bioavailability (71% and 95%, respectively). The data show that naratriptan is a selective agonist at 5HT1B/1D receptors, with a pharmacological profile very similar to that of sumatriptan, albeit 2-3 fold more potent. These observations, coupled with high oral bioavailability in animals, suggest that naratriptan has the profile of an orally effective anti-migraine drug. 相似文献