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91.
Hans Carlson 《Acta physiologica (Oxford, England)》1978,103(2):198-209
A histochemical analysis has been performed of the activity of myofibrillar ATPase, NADH2tetrazolium-reductase, succinic dehydrogenase and phosphorylase and of the content of fat and glycogen in the muscles of the cat's lumbar back region. The correlation between the fiber composition and the previously studied contraction properties of the muscles was analyzed. All muscles contain fibers with a low activity (type I) and such with a high activity (type II) of myofibrillar ATPase following preincubation at pH 9.4. Type II fibers showed either a low (type II A) or an intermediate (type II B) reaction when stained for ATPase, preincubation at pH 4.6. Type 1 fibers have a high, II A an intermediate-high and II B fibers a low activity of oxidative enzymes. The longissimus, iliocostalis and sacrocaudalis dorsalis lateralis muscles are characterized by high percentages of type II B fibers and low proportions of type I and type II A fibers. The central region of the longissimus which is connected to a well developed intermuscular septum is composed of a high proportion of type I fibers. The multifidi, interspinales and intertransversarii mediales muscles have higher proportions of type I and type II A fibers than the other muscles in the region. 相似文献
92.
We describe an extraction and an isocratic "high-performance" liquid-chromatographic (HPLC) separation of cyclosporine (CsA) and nine metabolites (M1, M8, M17, M18, M21, M25, M26, M203-218, and MUNDF1) from whole blood. Metabolites (for standards) were purified from human bile with liquid-liquid and solid-phase extractions, chromatographed on a cyanopropyl (CN) semipreparative HPLC column, and further purified on octyl, CN, and silica columns. The identity of each metabolite was verified with authentic standards on three chemically different HPLC columns and on the basis of cross-reactivity data from radioimmunoassay. For the routine analytical method, 1 mL of whole blood is diluted, hemolyzed, and applied to a Bond Elut CN (500 mg) cartridge to extract CsA, metabolites, and cyclosporin C, the internal standard. Interferences are removed by using four wash solutions and an additional cartridge of octyldecyl sorbent introduced prior to elution. Analytes are separated on a Zorbax CN analytical column maintained at 58 degrees C, with detection at 214 nm. Analytical recovery, as tested with three lots of CN sorbent, ranged from 47% to 95% for the 10 cyclosporines. Between-run CVs are less than 10% at 200 micrograms/L (concentration of each compound) and the standard curves are linear to 1500 micrograms/L. We also report a study of the separation mechanisms. 相似文献
93.
B E Carlson 《The American journal of orthopsychiatry》1986,56(2):308-312
It has been asserted that family violence is linked to the physical punishment of children. To explore children's views on different types of punishment, brief vignettes depicting a child misbehaving were presented to 201 9-12-year-olds who were asked to provide a "parental" response. Although few recommended physical punishment, the findings suggest that for some children physical punishment and aggression are associated. 相似文献
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Victor R. Carlson Iain S. Elliott Graham J. DeKeyser Christopher E. Pelt Lucas A. Anderson Jeremy M. Gililland 《The Journal of arthroplasty》2021,36(5):1799-1803
BackgroundDistortion is an intrinsic phenomenon associated with image-intensified fluoroscopy that is both poorly understood and infrequently appreciated by orthopedic surgeons. Little information exists regarding its potential influence on intraoperative parameters during orthopedic surgery, let alone during direct anterior (DA) total hip arthroplasty (THA). The purpose of this study was to quantify the amount of potential error caused by fluoroscopic distortion during DA THA.MethodsIntra-operative fluoroscopic pelvic images from 74 DA THAs were reviewed by two independent readers. All images were obtained using the same fluoroscopic C-arm unit with a radiopaque grid attached to the image intensifier. The vertical distortion from a straight central horizontal line at the peripheries of images were measured and summed to yield the combined vertical distortion similar to how a surgeon calculates a side to side comparison of limb lengths. Simple linear regression was used to evaluate associations between total distortion and patient demographics, operating theaters, and various operative parameters.ResultsThe average combined distortion was 10.0mm (range 2.0-20.0mm). There was a significant difference in the average distortion observed in different theaters (P < .001). There was no association between distortion and patient demographics or fluoroscopic time (all, P > .05).ConclusionFluoroscopic distortion is unpredictable and can cause a substantial amount of error when comparing limb lengths during DA THA. This is a critical finding as this amount of inaccuracy could lead to unintended implant positioning and limb-length discrepancies if unaccounted for. 相似文献
96.
Alex J. Lancaster Victor R. Carlson Christopher E. Pelt Lucas A. Anderson Christopher L. Peters Jeremy M. Gililland 《The Journal of arthroplasty》2021,36(6):2178-2183
BackgroundTwo-stage revision remains the standard of care for prosthetic joint infection after total hip arthroplasty. However, there are substantial complications associated with articulating antibiotic hip spacers. Handmade and molded spacers have been shown to have higher rates of spacer fracture than antibiotic-coated prostheses (ACPs). The aim of this study is to review outcomes with an implant that is often categorized as an ACP spacer, the Zimmer-Biomet StageOne Select Femoral Spacer (ZBSO).MethodsA retrospective review was performed of 63 patients who underwent placement of a ZBSO. Patients were compared based on whether or not an extended trochanteric osteotomy (ETO) was performed using Fisher’s exact and t-tests.ResultsFive patients were excluded due to lack of follow-up or death shortly after stage 1 surgery, leaving 58 patients. Spacer fracture was noted in 5 of 58 patients (8.6%). Sixteen patients underwent ETO and 25.0% suffered a spacer fracture compared to 2.3% without ETO (odds ratio 13.7, P = .0248). There was no association between patient demographics or ETO length and spacer fracture. Two patients had periprosthetic fractures (3.4%) and 4 had dislocations (6.9%). Forty-nine patients (84.4%) went on to second-stage revision; of those 26.5% failed to clear the infection and required an average of 2.2 additional surgeries.ConclusionThe ZBSO spacer has overall complication rates similar to previously reported spacer series. Although the ZBSO looks like an ACP spacer, in the setting of ETO, it behaves like a molded or handmade spacer with a high rate of spacer fracture (25%) due to the small diameter of the core. This implant should be used with caution in combination with an ETO. 相似文献
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99.
Pia Egerup Nicholas Carlson Louise Bruun Oestergaard Paul Blanche James R. Scott Mads Hornum Christian Torp-Pedersen Ole Bjarne Christiansen 《American journal of transplantation》2021,21(3):1171-1178
Information related to short- and long-term risks of children born to kidney-transplanted women remains limited. With the aim of investigating the risk of neonatal complications, and the short- and long-term risk of infections in offspring of kidney-transplanted women, all children born to kidney-transplanted women in Denmark from 1964 to 2016 were identified in a nationwide retrospective matched cohort study. A total of 124 children of kidney-transplanted women were identified and matched on gender, birth year, and number of siblings at birth 1:10 with children born to nontransplanted women identified in the Danish general population. Prevalence of low birth weight (37.9%, risk ratio [RR] = 12.61; 95% confidence interval [CI], 8.5-18.5), premature birth (46.0%, RR = 11.32; 95% CI, 8.1-15.7) and malformations (11.3%, RR = 1.98; 95% CI, 1.2-3.4) was increased in children of kidney-transplanted women compared with controls. Similarly, prevalence of hospitalization due to infection was increased during the first year of life (21.0%, RR = 1.94; 95% CI, 1.3-2.8), from age 1 to 5 (34.2%, RR = 1.89; 95% CI, 1.4-2.5), and overall (41.9%, RR = 1.67; 95% CI, 1.3-2.1). The risk of infection was also higher in children of kidney-transplanted mothers born preterm or with low birth weight compared with similar controls. In conclusion, risk of neonatal complications, malformations, and both early and late infection were increased in children born to kidney-transplanted women. 相似文献
100.
We present 2 cases of polymicrobial catheter sepsis in patients with long term central venous catheters who were receiving home parenteral nutrition. Both patients were generally unwell with haemodynamic instability. Attempts at catheter salvage by combined antibiotic and fibrinolytic administration through the central line were unsuccessful and resulted in patient deterioration. Catheters were removed in both patients. We conclude that catheter salvage should be considered very carefully in patients with polymicrobial catheter sepsis and there should be a low threshold for catheter removal in these cases. 相似文献