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991.
992.
ACB Molteno FRCS FRACO J. Hoare-Nairne FRACO † GF Sanderson BSc FBOA DA Peart MB ChB FCS IJ Hodgkinson MSc PhD ‡ 《Clinical & experimental ophthalmology》1993,21(4):257-265
The Otago photoscreener is a 35 mm single lens reflex camera in which the flash light comes from a narrow ring around the outer margin of its lens. The margin is also the limiting aperture of the optic system and in the centre of the lens is a flickering fixation light. In a colour photograph taken at a distance of 66 cm from the face of the subject who is accurately focusing on and fixing the camera fixation light with both eyes, the fundus reflex in each pupil is very dark red and the corneal light reflexes are symmetrical. If either or both eyes are not appropriately focused or fixing, the fundus reflex is brighter and yellow or white. This article describes a prospective trial of the performance of the Otago photoscreener in a series of 1000 infants with actual or suspected amblyopia, refractive error or strabismus. In this study photoscreening showed a sensitivity of 94% and a specificity of 79%. Photoscreening also identified some cases of esotropia and of refractive error which were missed on clinical examination. In this series photoscreening passed as normal three children with mild to moderately severe amblyopia. This represents les than 1 % of the clinically abnormal children. 相似文献
993.
Detrano R; MacIntyre WJ; Salcedo EE; O'Donnell J; Underwood DA; Simpfendorfer C; Go RT; Jones H; Butters K; Leatherman J 《Radiology》1985,155(1):19-23
Forty-three patients who had undergone direct-contrast ventriculography were submitted to intravenous digital subtraction ventriculography and first-pass radionuclide ventriculography to compare the left ventricular ejection fractions obtained by each method. Ejection fractions were calculated by the area-length method from the direct contrast ventriculograms, by both area-length and videodensitometric methods from the digital subtraction ventriculograms, and by count densitometry from the radionuclide ventriculograms. Satisfactory correlations were found between values obtained by the late mask resubtracted videodensitometric method and the radionuclide method (r = 0.85) and by the digital ventriculographic area length method and direct-contrast method (r = 0.88). Videodensitometric methods may be an alternative way to estimate left ventricular ejection fractions accurately without reliance on geometric assumptions about the shape of the left ventricular cavity. 相似文献
994.
Supratentorial ependymoma: CT appearance 总被引:5,自引:0,他引:5
Armington WG; Osborn AG; Cubberley DA; Harnsberger HR; Boyer R; Naidich TP; Sherry RG 《Radiology》1985,157(2):367-372
The computed tomographic appearances of 22 biopsy-proved supratentorial ependymomas were analyzed. Supratentorial ependymomas were usually intraparenchymal, larger than 4 cm, and cystic. Contrast enhancement was moderate to intense, with homogeneous or ring-enhancement patterns commonly seen. Intratumoral calcification was present in one-third of the cases, while hydrocephalus and peritumoral edema were seen in 50%. Intratumoral hemorrhage was not a characteristic of the lesion. In contrast to cellular ependymomas, malignant ependymomas and ependymoblastomas demonstrate higher attenuation prior to administration of contrast material, more intense enhancement, lower frequency of calcification within the tumor, and less distinct margination. 相似文献
995.
Feinberg DA; Crooks LE; Hoenninger JC; Watts JC; Arakawa M; Chang H; Kaufman L 《Radiology》1986,158(3):811-817
Section thickness in two-dimensional Fourier transform (FT) imaging is dependent on gradient strength and the shape of the radio-frequency pulses used to excite the nuclei. By manipulation of these parameters, it is possible to obtain 2.5-mm-thick sections in contiguous, multisection imaging. Because this method is efficient in imaging with long repetition times (TR), it effectively complements three-dimensional FT thin-section imaging techniques, which require imaging with short TRs. Fifteen double-echo, contiguous images of 0.9 X 0.9 X 2.5-mm resolution were obtained in 17.1 minutes for a TR of 2 seconds. 相似文献
996.
SPRIGGS DA; FRENCH JM; MURDY JM; CURLESS RH; BATES D; JAMES OFW 《QJM : monthly journal of the Association of Physicians》1992,83(4):555-562
In a case-controlled study we recruited 400 patients admittedto hospital with stroke and 400 community controls matched forage, gender and family practitioner. Snoring history was obtainedfrom 326 patients and 345 controls. Odds ratio for admissionto hospital with stroke was 3.2 (95 per cent confidence intervals2.34.4) for regular snorers against those who did notsnore regularly. This risk was independent for age, gender andother risk factors for stroke. Snoring did not increase thechances of stroke during sleep. Level of consciousness was reducedmore frequently in snorers (p = 0.0003). As the frequency ofsnoring increased so did the mortality to 6 months (p = 0.0006).Snoring is an important risk factor for stroke and adverselyaffects the prognosis in patients admitted to hospital withstroke. 相似文献
997.
998.
999.
Philip Jacobs Rita Yim Arto Ohinmaa Ken Eng Carolyn S Dewa Roger Bland Ray Block Mel Slomp 《Revue canadienne de psychiatrie》2008,53(5):306-313
OBJECTIVE: To measure total public and private expenditures on mental health in each province. METHOD: Data for expenditures on mental health services were collected in the following categories: physician expenditures (general and psychiatrist fees for service and alternative funding), inpatient hospital (psychiatric and general), outpatient hospital, community mental health, pharmaceuticals, and substance abuse. Data for 2 years, 2003 and 2004, were collected from the Canadian Institute for Health Information (hospital inpatient and fees for service physicians), the individual provinces (pharmaceuticals, alternative physician payments, hospital outpatient, and community), and the Canadian Centre on Substance Abuse. Totals were expressed in terms of per capita and as a percentage of total provincial health spending. RESULTS: Total spending on mental health was $6.6 billion, of which $5.5 billion was from public sources. Nationally, the largest portion of expenditures was for hospitals, followed by community mental health expenses and pharmaceuticals. This varied by province. Public mental health spending was 6% of total public spending on health, while total mental health spending was 5% of total health spending. CONCLUSIONS: Canadian public mental health spending is lower than most developed countries, and a little below the minimum acceptable amount (5%) stated by the European Mental Health Economics Network. 相似文献
1000.
目的检测无基因重复的腓骨肌萎缩症患者间隙连接蛋白32(connexin32,Cx32)基因的突变情况。方法应用变性高效液相色谱(DHPLC)结合混合样品池法和脱氧核糖核酸(DNA)序列测定对1个临床可疑的X连锁显性遗传的腓骨肌萎缩症CMTX1型家系的先证者和15名家庭成员及60名家系外健康对照者进行Cx32基因外显子2的基因编码区突变检测,分3个片段扩增其基因编码区全长。结果先证者在片段2的DHPLC中发现杂合双峰,经DNA序列测定证实其Cx32外显子2发生Leu89Pro(266T→C)错义突变;家系内其他4例发病者和5名未发病者Cx32外显子2都有与先证者一致的DHPLC杂合双峰。60名健康对照者中未发现上述改变。结论Leu89Pro是该家系的致病性突变。该突变体的致病机制如何,有待于做进一步研究。 相似文献