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81.
Mitchell DG; Merton D; Needleman L; Kurtz AB; Goldberg BB; Levy D; Rifkin MD; Pennell RG; Vilaro M; Baltarowich O 《Radiology》1988,167(2):303-306
Color Doppler imaging (CDI) can demonstrate the relative direction and velocity of blood flow in color, superimposed on a conventional gray-scale ultrasound image that depicts stationary tissue. Twenty-five infants were studied with portable CDI in the coronal, sagittal, and axial planes. Bilateral antegrade flow was noted in the anterior, middle, and posterior cerebral arteries in all patients. Multiplanar CDI can image flow in the circle of Willis and its tributaries and branches. 相似文献
82.
Complications of spinal cord arteriography: prospective assessment of risk for diagnostic procedures
Forbes G; Nichols DA; Jack CR Jr; Ilstrup DM; Kispert DB; Piepgras DG; Wiebers DO; Earnest F th; Axley PL 《Radiology》1988,169(2):479-484
A prospective study was done of complications associated with 134 consecutive diagnostic spinal cord arteriograms in 96 patients (63 men and 33 women aged 17-78 years). Patients were examined for either arteriovenous malformation (n = 88) or tumor (n = 8), as indicated by myelography. Among the complications, 11 (8.2%) were local, five (3.7%) were systemic nonneurologic, and three (2.2%) were neurologic (two were associated with full recovery in less than 24 hours, and one was associated with full recovery in less than 1 week). No specific clinical or technical factors were significantly associated with the development of neurologic complications. Details of the clinical profile, angiographic technique, and pathologic findings for each patient were recorded and analyzed with respect to the potential risk for arteriographic complications. Diagnostic spinal cord arteriography had an acceptable risk within the range of other neuroangiographic diagnostic procedures. 相似文献
83.
Spacing of cytochrome oxidase blobs in visual cortex of normal and strabismic monkeys 总被引:3,自引:3,他引:0
Murphy KM; Jones DG; Fenstemaker SB; Pegado VD; Kiorpes L; Movshon JA 《Cerebral cortex (New York, N.Y. : 1991)》1998,8(3):237-244
Some models of visual cortical development are based on the assumption that
the tangential organization of V1 is not determined prior to visual
experience. In these models, correlated binocular activity is a key element
in the formation of visual cortical columns, and when the degree of
interocular correlation is reduced the models predict an increase in column
spacing. To examine this prediction we measured the spacing of columns, as
defined by cytochrome oxidase (CO) blobs, in the visual cortex of monkeys
whose binocular vision was either normal or disrupted by a strabismus. The
spatial distribution of blobs was examined in seven normal and five
strabismic macaques. Tangential sections through the upper layers of the
visual cortex were stained to reveal the two-dimensional (2D) pattern of CO
blobs. Each blob was localized and their center-to-center spacing, packing
arrangement and density were calculated using 2D nearest-neighbor spatial
analyses. The mean center-to-center spacing of blobs (590 microm for
normally reared and 598 microm for strabismic macaques) and the mean
density of blobs (3.67 blobs/mm2 for normally reared and 3.45 blobs/mm2 for
strabismic macaques) were not significantly different. In addition, the 2D
packing arrangement of the blobs was not affected by strabismus. While it
is clear that neural activity plays a key role in the elaboration and
refinement of ocular dominance cortical modules, we conclude that it does
not determine the spatial period of the pattern of CO blobs. This suggests
that aspects of the neural circuitry underlying the columnar architecture
of the visual cortex are established prenatally and its fundamental
periodicity is not modifiable by experience.
相似文献
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86.
Klatskin tumors of the bile ducts: sonographic appearance 总被引:4,自引:0,他引:4
The authors present 3 cases of surgically proved Klatskin tumor diagnosed by ultrasound alone. Sonographic features of these tumors include (a) dilatation of the intrahepatic biliary ducts but not the extrahepatic duct, (b) non-union of the right and left hepatic ducts, and (c) small, solid masses at the hepatic hilus. Local spread to the liver may also be seen. If the pancreas appears normal and no primary tumor can be found, Klatskin tumor can be diagnosed with a high degree of accuracy. 相似文献
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88.
Parul J Shukla Savio G Barreto MMS Bedi N Bheerappa Adarsh Chaudhary MD Gandhi M Jacob S Jesvanth DG Kannan Vinay K Kapoor A Kumar KK Maudar Hariharan Ramesh RA Sastry Rajan Saxena Ajit Sewkani S Sharma Shailesh V Shrikhande A Singh Rajneesh K Singh R Surendran Subodh Varshney V Verma V Vimalraj 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2009,11(8):638-644
Background:
There have been an increasing number of reports world-wide relating improved outcomes after pancreatic resections to high volumes thereby supporting the idea of centralization of pancreatic resectional surgery. To date there has been no collective attempt from India at addressing this issue. This cohort study analysed peri-operative outcomes after pancreatoduodenectomy (PD) at seven major Indian centres.Materials and Methods:
Between January 2005 and December 2007, retrospective data on PDs, including intra-operative and post-operative factors, were obtained from seven major centres for pancreatic surgery in India.Results:
Between January 2005 and December 2007, a total of 718 PDs were performed in India at the seven centres. The median number of PDs performed per year was 34 (range 9–54). The median number of PDs per surgeon per year was 16 (range 7–38). Ninety-four per cent of surgeries were performed for suspected malignancy in the pancreatic head and periampullary region. The median mortality rate per centre was four (range 2–5%). Wound infections were the commonest complication with a median incidence per centre of 18% (range 9.3–32.2%), and the median post-operative duration of hospital stay was 16 days (range 4–100 days).Conclusions:
This is the first multi-centric report of peri-operative outcomes of PD from India. The results from these specialist centers are very acceptable, and appear to support the thrust towards centralization. 相似文献89.
Parveen Rewri Aprajita Lohan Sagarika Aggarwal Priyanka Chodhary Aparna Singhal 《Indian journal of ophthalmology》2021,69(6):1575
Purpose:The aim of this study was to know proportion of white cataracts from among patients coming for cataract surgery, and to find causes delaying uptake of cataract surgery.Methods:A hospital-based, prospective study enrolled patients of senile cataract between April 2018 and March 2019. The proportion of white cataract was calculated and underlying causes delaying uptake of cataract surgery studied.Results:White cataracts constituted 13.5% of total 3634 senile cataract patients, with gender disparity disfavoring women. Bilateral white cataract was presentation in 39 (8%) patients and lens-related glaucoma in 24 (5%) patients. Pseudophakia in the other eye was single most common cause of delay.Conclusion:A large proportion of white cataracts suggest that penetration of cataract surgical services in not reaching to the most eligible individual. 相似文献
90.