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31.
Severe spondylolisthesis. Reduction and internal fixation 总被引:11,自引:0,他引:11
The authors have developed and algorithm for management of spondylolysis and spondylolisthesis. Since March 1983, 15 patients with an average age of 20 years and with greater than 50% anterior displacement have been treated. The mean follow-up period is 24 months. Before surgery the average anterior displacement was 72%, the average delta angle at L5-S1 representing kyphosis was 73 degrees, and the average lumbar lordosis from L1 to L5 was 64 degrees. An anterior release and fusion was combined with a posterior reduction and instrumentation using the internal fixator. Correction of the anterior displacement averaged 46%, while the kyphosis was corrected a mean of 20 degrees and the lordosis a mean of 12 degrees. The L4 segment was preserved in 13 cases and the L4-L5 angle was improved by a mean of 7 degrees. Postoperative pain and function were improved in all cases. Neurologic complications occurred in four patients, three permanent and one temporary. Hardware failure occurred in two patients, and reoperation has been required in one. Further follow-up evaluation of this technique is required. 相似文献
32.
33.
W D Foltz Y Yang J J Graham J S Detsky G A Wright A J Dick 《Magnetic resonance in medicine》2006,56(6):1311-1319
MRI evaluations of intramyocardial hemorrhage in acute infarction have relied on T(2) and T(2)(*) shortening only. We propose a more comprehensive evaluation of hemorrhagic infarction based on the concept that fluctuations in T(2) and T(1) relaxation in acute reperfused infarction will reflect transient edema and hemoglobin oxidative denaturation to uncompartmentalized methemoglobin. Anteroapical infarction was created via percutaneous balloon in young swine (22-25 kg, N = 12). T(2), T(1), diastolic wall thickness (DWT), and the Gd-DTPA partition coefficient (lambda) were measured on days 0, 2, and 7. DWT was elevated at 1 hr postreperfusion (128% +/- 53%, P = 0.0001), and alleviated on days 2 and 7 (48% +/- 10%, P = 0.008; 53% +/- 24%, P = 0.003). T(2) and T(1) elevations were coincident with early edema (DeltaT(2) = 55% +/- 24%, P < 0.0001; DeltaT(1) = 27% +/- 18%, P < 0.04). T(2) and T(1) were nearly normal on day 2 (DeltaT(2) = 8% +/- 8%, P = 0.27; DeltaT(1) = 0% +/- 1%, P = 0.65). On day 7, T(2) increased while T(1) decreased (DeltaT(2) = 27% +/- 16%, P = 0.005; DeltaT(1) = -14% +/- 10%, P = 0.02). Lambda was elevated by >150% at all time points (P < or = 0.002). Histology verified hemorrhagic injury. T(1) and T(2) fluctuations are consistent with transient edema, as well as hemoglobin oxidative denaturation to decompartmentalized methemoglobin. This methodological development may broaden our understanding of hemorrhagic microvascular injury and improve its detection in clinical populations. 相似文献
34.
L Cornet M Richard-Kadio H A N'Guessan P Yapo H Hossoko R Dick J M Casanelli 《Bulletin de la Societe de pathologie exotique (1990)》1992,85(5):355-358
Buruli's ulcer is a real disease of public health. In Ivory Coast, 50 patients were treated from February 1987 to August 1991. It realizes a real destruction of skin and subcutaneous tissues. The germ is Mycobacterium ulcerans. The preferential localisation is the limbs in children of 14 years old. Large ulcer with polycyclic margin are treated by extended excision and thin skin grafts. But deformities persist after the surgical treatment. Hospitalisation is long and drugs are expensive. 相似文献
35.
Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
36.
We measured the amounts of three types of radiographic contrast media (RCM) that could be entrapped in liposomes prepared by the dehydration-rehydration vesicle (DRV) technique. To make DRVs, one initially makes water-containing, small unilamellar vesicles, adds contrast media and lyophilizes the mixture. Upon rehydration, the DRVs re-form, passively entrapping RCM. Diatrizoate, iohexol and iotrolan proved to be entrappable in similar amounts (diatrizoate was best), but all of these amounts were less than for other small molecules, such as carboxyfluorescein (P less than 0.05). Entrapment was directly proportional to lipid concentration (r = 0.76; P less than 0.002), and inversely related to iodine concentration (r = 0.86; P less than 0.002). Under ideal conditions with neutral lipids, 19.45 +/- 9.9% of diatrizoate was entrapped, corresponding to 1.05 +/- 0.50 g I per g lipid. These values are close to those achievable for large unilamellar vesicles. Use of an automated mixing device (the Microfluidizer) in place of sonication, facilitated production of large liposome batches and improved entrapment (P less than 0.05). Computed tomography (CT) scans of rats showed 30 and 218 HU of liver and spleen enhancement, respectively, per g I/kg injected DRVs. These studies showed this method (possible augmented by the Microfluidizer) allows efficient production of contrast-carrying liposomes. 相似文献
37.
Effects of vitamin D and calcium supplementation on falls: a randomized controlled trial. 总被引:21,自引:0,他引:21
Heike A Bischoff Hannes B St?helin Walter Dick Regula Akos Margrith Knecht Christian Salis Matthias Nebiker Robert Theiler Michael Pfeifer Bettina Begerow Robert A Lew Martin Conzelmann 《Journal of bone and mineral research》2003,18(2):343-351
Specific receptors for vitamin D have been identified in human muscle tissue. Cross-sectional studies show that elderly persons with higher vitamin D serum levels have increased muscle strength and a lower number of falls. We hypothesized that vitamin D and calcium supplementation would improve musculoskeletal function and decrease falls. In a double-blind randomized controlled trial, we studied 122 elderly women (mean age, 85.3 years; range, 63-99 years) in long-stay geriatric care. Participants received 1200 mg calcium plus 800 IU cholecalciferol (Cal+D-group; n = 62) or 1200 mg calcium (Cal-group; n = 60) per day over a 12-week treatment period. The number of falls per person (0, 1, 2-5, 6-7, >7 falls) was compared between the treatment groups. In an intention to treat analysis, a Poisson regression model was used to compare falls after controlling for age, number of falls in a 6-week pretreatment period, and baseline 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum concentrations. Among fallers in the treatment period, crude excessive fall rate (treatment - pretreatment falls) was compared between treatment groups. Change in musculoskeletal function (summed score of knee flexor and extensor strength, grip strength, and the timed up&go test) was measured as a secondary outcome. Among subjects in the Cal+D-group, there were significant increases in median serum 25-hydroxyvitamin D (+71%) and 1,25-dihydroxyvitamin D (+8%). Before treatment, mean observed number of falls per person per week was 0.059 in the Cal+D-group and 0.056 in the Cal-group. In the 12-week treatment period, mean number of falls per person per week was 0.034 in the Cal+D-group and 0.076 in the Cal-group. After adjustment, Cal+D-treatment accounted for a 49% reduction of falls (95% CI, 14-71%; p < 0.01) based on the fall categories stated above. Among fallers of the treatment period, the crude average number of excessive falls was significantly higher in the Cal-group (p = 0.045). Musculoskeletal function improved significantly in the Cal+D-group (p = 0.0094). A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49% compared with calcium alone. Over this short-term intervention, recurrent fallers seem to benefit most by the treatment. The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function. 相似文献
38.
Maroun Dick M.D. Tulio E. Bertorini M.D. Masanori Igarashi M.D. 《Developmental medicine and child neurology》1992,34(3):262-265
Respiratory failure is an unusual initial manifestation of congenital muscular dystrophy. The authors describe a case of congenital muscular dystrophy in a patient presenting with rhabdomyolysis at birth. Despite an initially poor prognosis, aggressive respiratory therapy during the neonatal period permitted normal subsequent development. The muscular dystrophy predominantly involved the respiratory muscles. 相似文献
39.
T C Greiner C P Burns F R Dick K M Henry I Mahmood 《American journal of clinical pathology》1992,98(5):522-525
Congenital dyserythropoietic anemia type II is a rare disorder that is often diagnosed in patients before age 20 years. Patients with this disorder, which is also called hereditary erythroblastic multinuclearity associated with a positive acidified serum lysis test, may have symptoms of iron overload. The purpose of this case report is to alert physicians to consider the diagnosis of congenital dyserythropoietic anemia type II in elderly patients who have anemia and iron overload. 相似文献
40.
Christine N Vidal Rob Nicolson Timothy J DeVito Kiralee M Hayashi Jennifer A Geaga Dick J Drost Peter C Williamson Nagalingam Rajakumar Yihong Sui Rebecca A Dutton Arthur W Toga Paul M Thompson 《Neuropsychopharmacology》2006,60(3):218-225
BACKGROUND: Volumetric studies have reported reductions in the size of the corpus callosum (CC) in autism, but the callosal regions contributing to this deficit have differed among studies. In this study, a computational method was used to detect and map the spatial pattern of CC abnormalities in male patients with autism. METHODS: Twenty-four boys with autism (aged 10.0 +/- 3.3 years) and 26 control boys (aged 11.0 +/- 2.5 years) underwent a magnetic resonance imaging (MRI) scan at 3 Tesla. Total and regional areas of the CC were determined using traditional morphometric methods. Three-dimensional (3D) surface models of the CC were also created from the MRI scans. Statistical maps were created to visualize morphologic variability of the CC and to localize regions of callosal thinning in autism. RESULTS: Traditional morphometric methods detected a significant reduction in the total callosal area and in the anterior third of the CC in patients with autism; however, 3D maps revealed significant reductions in both the splenium and genu of the CC in patients. CONCLUSIONS: Statistical maps of the CC revealed callosal deficits in autism with greater precision than traditional morphometric methods. These abnormalities suggest aberrant connections between cortical regions, which is consistent with the hypothesis of abnormal cortical connectivity in autism. 相似文献