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81.
BackgroundAccurate preoperative planning is a key component of successful total hip arthroplasty (THA). The purpose of the present study was to compare the accuracy and reliability of three-dimensional (hipEOS) and common digital two-dimensional (TraumaCad) templating with special focus on stem morphology.Methods51 patients undergoing THA were randomized to two groups. Preoperative planning was performed on 23 patients with hipEOS (3D) and on 28 patients with TraumaCad (2D) planning software. Planning results were compared with the implanted component size. Inter- and intraobserver reliability as well as planning accuracy of both planning methods with special focus on straight and short stem design were recorded.ResultsIntraobserver reliability of both planning methods was good for component planning (ICC2,1: 0.835-0.967). Interobserver ICC2,1 for stem and cup planning were higher for 3D templating (3D ICC2,1: 0.906-0.918 vs. 2D ICC2,1: 0.835-0.843). Total stem and cup size predictions were within 2 sizes for 3D and within 3 sizes for 2D planning. Comparing short stem planning accuracy of both planning methods, absolute difference between implanted and planned component size was significantly lower in 3D planning (P = .029). There was no significant difference in straight stem (P = .935) and cup (P = .954) planning accuracy.ConclusionOur findings suggest that 3D templating with hipEOS software has a good overall reliability and may have a better planning accuracy of short stem prostheses than digital templating with TraumaCad software. Assuming that the number of implanted short stem prostheses will further increase in coming years, a more precise planning with 3D technique can contribute to improve surgery outcome.  相似文献   
82.
BackgroundClostridioides difficile infection (CDI) is traditionally taught to be an antibiotic associated diarrheal infection. This diagnosis is based on the presence of clinical symptoms (usually defined as more than 3 watery, loose or unformed stool within 24 h) coupled with a diagnostic test. There is now a new presentation of CDI, including progression to toxic megacolon, in patients without diarrhea.MethodsWe report a case series of 9 surgical patients from a single institution who developed CDI without preceding diarrhea.ResultAll 9 patients had CDI with positive laboratory testing for C. difficile toxin. They, however, presented with a lack of or minimal bowel movements. Six patients had rapid development of abdominal distention, 1 patient had a single episode of watery stool in 3 days, while the other 2 patients presented with constipation. Seven patients received stool softeners, suppositories and/or enemas for presumed constipation. Four patients had a mild course of infection and were successfully treated medically. The other 5 patients developed toxic megacolon, and eventually required total abdominal colectomy. Out of the 5 patients that required total colectomy, 2 expired.ConclusionCDI must be suspected in patients who rapidly develop abdominal distention, vague abdominal complaints or change in bowel function even in the absence of diarrhea, especially if coupled with multi-system organ failure.  相似文献   
83.
Yoga interventions can reduce stress, but the mechanisms underlying that stress reduction remain largely unidentified. Understanding how yoga works is essential to optimizing interventions. The present study tested five potential psychosocial mechanisms (increased mindfulness, interoceptive awareness, spiritual well-being, self-compassion and self-control) that have been proposed to explain yoga's impact on stress. Forty-two participants (62% female; 64% White) in a yoga program for stress reduction completed surveys at baseline (T1), mid-intervention (T2) and post-intervention (12 weeks; T3). We measured two aspects of stress, perceived stress and stress reactivity. Changes were assessed with paired t-tests; associations between changes in mechanisms were tested in residual change models. Only stress reactivity decreased, on average, from T1 to T3. Except for self-compassion, all psychosocial mechanisms increased from T1 to T3, with minimal changes from T2 to T3. Except for self-control, increases in each mechanism were strongly associated with decreases in both measures of stress between T1 and T2 and decreases in perceived stress from T1 to T3 (all p's < 0.05). Increased psychosocial resources are associated with stress reduction. Yoga interventions targeting these resources may show stronger stress reduction effects. Future research should test these linkages more rigorously using active comparison groups and larger samples.  相似文献   
84.
85.
Induction of replicative competence ("priming") in normal liver   总被引:3,自引:0,他引:3  
J E Mead  L Braun  D A Martin  N Fausto 《Cancer research》1990,50(21):7023-7030
We have used a system of nutritional manipulation to investigate whether hepatocytes of the normal liver can be primed for replication in vivo. In this system, rats that are denied protein for 3 days undergo a burst of hepatic DNA synthesis and mitosis when they are refed amino acids, while normally fed or starved rats do not respond. To determine if hepatocytes of protein deprived (PD) rats have been "primed" for replication, we examined changes in protooncogene expression in livers of PD rats to see if they would mimic the pattern of gene expression that is induced early after partial hepatectomy. c-jun, c-myc, and p53 mRNAs were elevated in livers of PD rats, while c-fos and c-ras genes were not expressed. The administration of amino acids to PD rats stimulated hepatic DNA synthesis in a shorter period than is required after partial hepatectomy and induced p53 and c-ras expression. In culture, hepatocytes from PD rats had higher levels of c-myc mRNA, underwent morphological changes more rapidly, and reached maximum rates of DNA synthesis earlier than normal hepatocytes. In both normal and primed hepatocyte cultures, transforming growth factor alpha stimulated DNA synthesis more effectively than epidermal growth factor. We conclude that hepatocytes pass through a priming stage before they proliferate and that replicative competence without DNA synthesis can be induced in hepatocytes in the normal liver.  相似文献   
86.
M Goyette  R Faris  L Braun  D Hixson  N Fausto 《Cancer research》1990,50(15):4809-4817
We have established an in vivo/in vitro system in which epithelial cells ("oval cells") isolated from livers of rats fed a carcinogenic diet for a very brief period are placed in culture and transfected with an oncogene. Injection s.c. into nude mice of oval cells transfected with the activated c-Ha-ras (EJ oncogene) produces tumors with morphological features of differentiated hepatocellular carcinomas. Using monoclonal antibodies that can recognize hepatocyte, oval cell, and tumor antigens, we investigated the expression of these antigens in oval cells in culture, transfected with either the EJ oncogene or the normal c-Ha-ras allele and in tumors derived from the oncogene-transfected cells. We show that EJ-transfected cells and most particularly the tumors they produce expressed hepatocyte and oval cell antigens not detectable in untransfected cells or cells transfected with the normal c-Ha-ras gene. Furthermore, we found that in cloned tumor cells, the expression of hepatocyte antigens could be induced by changes in culture conditions and was accompanied by a decrease in the expression of oval cell markers. Trabecular hepatocellular carcinomas had higher reactivity toward monoclonal antibodies recognizing hepatocyte antigens while tumors with glandular architecture reacted predominantly with monoclonal antibodies against oval cells. We conclude that, in addition to its tumorigenic effect, the EJ oncogene induced the differentiation of tumor cells toward the hepatocyte lineage. In addition, the data provide further confirmation that oval cells can serve as progenitors of differentiated hepatocellular carcinomas.  相似文献   
87.
OBJECTIVE: To assess the 1-year outcome of standard medical care of acute ankle sprains in a general clinic-based population. DESIGN: A self-administered survey was mailed to all adult patients who presented to a health system provider for evaluation of ankle sprain. SETTING: A regional primary care health system. PARTICIPANTS: Four hundred sixty-seven (66.5%) of 702 patients with ankle sprains evaluated by a system physician from April 1, 1995, to March 31, 1996. MAIN OUTCOME MEASURES: Prevalence and severity of self-reported ankle pain, swelling, perceived instability, and perceived weakness 6 to 18 months after medical evaluation. RESULTS: Most patients sought medical evaluation shortly after injury and were immobilized or braced; 32.7% reported formal or home-based physical therapy. Six to 18 months after injury, 72.6% reported residual symptoms. Of these, 40.4% reported at least 1 moderate to severe symptom, most commonly perceived ankle weakness; 40.3% were unable to walk 1 mile; and 43.3% were unable to jump or pivot on the ankle without symptoms. Factors associated with moderate to severe residual symptoms were reinjury of the ankle (odds ratio [OR], 7.21; 95% confidence interval [CI], 4.14-12.68), activity restriction longer than 1 week (OR, 2.04; 95% CI, 1.25-3.32), and limited weight bearing longer than 28 days (OR, 2.16; 95% CI, 1.28-3.63). CONCLUSIONS: Residual lifestyle-limiting symptoms are common 6 to 18 months after an ankle sprain. Ankle sprains may be more problematic than generally thought, or standard medical treatment may be inadequate. Further studies evaluating treatment regimens are needed to identify effective methods to reduce the long-term functional limitations of ankle sprain in general clinic populations.  相似文献   
88.
Human milk is commonly considered to be unique when compared with the milk of other species with regard to its high content of complex fucosylated and sialylated lactose-derived oligosaccharides. We describe the application of high-pH anion-exchange chromatography with pulsed amperometric detection and TLC to characterize and quantitate neutral and sialylated lactose-derived oligosaccharides in milk from three Asian elephants and human milk. The lactose contents of elephant and human milks were 25-30 g/l and about 66 g/l respectively, whereas total oligosaccharide concentration was about three times higher in elephant milk and comprised up to 40% (10% in human milk) of the carbohydrate content. The ratio neutral: acidic components was different in the milk of the two species; in elephant milk, the N-acetylneuraminic acid-containing oligosaccharides made up almost half of the total amount v. 30% in human milk. Most oligosaccharides in elephant milk were more fucosylated and/or sialylated compared with human milk components. By mild acid hydrolysis, fucose and N-acetylneuraminic acid were cleaved off from complex components, and this resulted in increased amounts of fucose, galactose, N-acetylneuraminic acid, lactose and lacto-N-neo-tetraose. Unique to elephant milk are the high levels of 3'-galactosyllactose (up to 4 g/l) and lacto-N-neo-tetraose which are present in human milk only in trace amounts. Elephant and human milks have high levels and unique patterns of oligosaccharides which may reflect the relative importance of these components in neonatal host defence, in endothelial leucocyte interactions or in brain development.  相似文献   
89.
The location of the center of resistance of the dentomaxillary complex has recently been identified more accurately than before. Based on this new finding, various modifications of the common facebow are presented for use in protraction therapy. Clinical applications for specific treatment objectives are also reviewed. Orthopedic and biomechanical implications of various standard retraction type extraoral appliances are also analyzed.  相似文献   
90.
Particle-mediated delivery was used as a method to vaccinate ruminants with a DNA vaccine. The optimal conditions for gene gun-based delivery of gold particles into the epidermal layer of the skin were determined. After delivery of the gold particles, an inflammatory response was observed. This response occurred regardless of the presence of plasmid and therefore was a result of the physical disturbance of the skin by the gold particles. To identify transfected cells, a plasmid expressing a green fluorescent protein was delivered into the skin. Fluorescent cells were located primarily in the outermost layers of the epidermis and outside the core of gold particles deposited by the gene gun. Cattle were immunized by gene gun with a plasmid expressing a truncated, secreted form of bovine herpesvirus-1 glycoprotein D. Serum antibody responses, antigen-specific proliferation, and interferon-gamma secretion by peripheral blood lymphocytes were demonstrated. These immune responses were found to be of long duration and sufficient magnitude to protect cattle against challenge with bovine herpesvirus-1, which demonstrates the efficacy of gene gun-based delivery of DNA vaccines to target species.  相似文献   
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