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61.

Background

Pre- and postoperative knee kinematics in unicompartmental knee arthroplasty (UKA) can be theoretically related to clinical outcome and longevity after UKA with regard to ligament function and the degree of arthritic changes. However, the preoperative knee kinematics of patients indicated for UKA remain to be elucidated, and it is also unclear whether the preoperative kinematics can be maintained by the UKA procedure. The objective of this study was to examine the in vivo pre- and postoperative three-dimensional knee kinematics in UKA while referencing the normal knee kinematics reported in our previous study.

Methods

We analyzed the knee kinematics in 17 knees (14 patients) undergoing UKA via a three-dimensional to two-dimensional registration technique employing femoral condylar translation and femoral axial rotation. The pre- and postoperative knee kinematics during squat motion were evaluated in the same subjects, employing consistent evaluation parameters.

Results

On average, both pre- and postoperative knee kinematics in the range 10–100° of knee flexion demonstrated near-consistent femoral external rotation and anterior translation of the medial condyle and posterior translation of the lateral condyle. However, the mean femoral external rotation angle and the posterior translation of the lateral condyle postoperatively were significantly smaller than the values observed preoperatively.

Discussion

Although the patterns of preoperative knee motion were similar to those seen in normal knees, the magnitude of this motion varied widely between patients, so it was not necessarily representative of normal knees. These variations may be due to the varying degrees of arthritic changes caused by osteoarthritis. Although the patterns of knee kinematics were largely maintained by the UKA procedure, the causes of the significant reductions in the magnitude of motion upon performing the UKA procedure should be investigated in subsequent studies with a larger number of patients.  相似文献   
62.
63.
The objective of this study was to record the clinical course of osteoporosis over time in Japanese women. We hypothesized that successful control of acute pain associated with osteoporosis will allow better treatment for health-related problems. To confirm this working hypothesis, we developed the Japan Questionnaire for Osteoporotic Pain (JQ22) to measure health status associated with osteoporosis. We examined the validity and reliability of the JQ22 compared with the current gold standard scale for back pain, the Roland Morris questionnaire (RDQ). A total of 125 women who were more than 65 years old, had an acute back pain episode, and had a fragile vertebral fracture confirmed by X-ray and clinical signs, participated in this study. The psychometric analyses for validity and reliability were tested for the JQ22 and the RDQ. The time course up to 6 weeks was observed by investigating both changes in pain characteristics and its influence on related activities and social participation. Cronbach’s alpha coefficient was 0.979 and 0.919 for the JQ22 and RDQ, respectively. The Akaike Information Criterion (AIC) indicated that the JQ22 items were separated into four domains, which were sequentially arranged at the baseline and subsequently changed. This structure reflected osteoporotic back characteristics covering a range from pain to social activities. The JQ22 was shown to be a valid and reliable scale for patient-based measurement of osteoporotic back pain. It also revealed both changes in pain characteristics and the influence of pain on related activities and participation.  相似文献   
64.
65.

Background

Downstream activation through receptor tyrosine kinases (RTKs) plays important roles in carcinogenesis. In this study, we assessed the clinical involvement of Axl, an RTK, and its ligand, Gas6, in surgically treated lung adenocarcinoma.

Methods

Axl and Gas6 mRNA and protein expression levels were quantified using quantitative real-time polymerase chain reaction and immunohistochemistry, respectively, in completely resected lung adenocarcinoma tissues (n = 88) and were evaluated for correlation with clinicopathologic features and patient survival.

Results

Higher expressions of Axl mRNA/protein and Gas6 protein were significantly related to worse clinicopathological features and prognosis (5-year overall survival rates: Axl mRNA low: 72.3 %, high: 49.7 %, P = 0.047; Axl protein low: 77.5 %, high: 38.6 %, P < 0.001; and Gas6 protein low: 70.5 %, high: 48 %, P = 0.042). On the contrary, higher Gas6 mRNA expression was related to better clinicopathological features and prognosis (5-year overall survival rates: Gas6 mRNA low: 59.2 %, high: 81.8 %, P = 0.054). Multivariate analysis suggests that high Axl mRNA expression may be an independent factor for poor patient prognosis (P = 0.04).

Conclusions

In lung adenocarcinoma, Axl and Gas6 expression levels were associated with tumor advancement and patient survival, thus rendering them as reliable biomarkers and potential targets for treatment of lung adenocarcinoma.
  相似文献   
66.

Purpose

Cardiac surgery for the patients with advanced liver cirrhosis is still challenging. High mortality has been reported in the literature. We evaluate the clinical outcome of cardiac surgery in patients with advanced liver cirrhosis.

Methods

Patients with advanced liver cirrhosis who underwent cardiac surgery between October 1999 and April 2009 were reviewed. The severity of liver cirrhosis was assessed using Child-Pugh class, Child-Pugh score, and MELD score. Advanced liver cirrhosis was defined as Child-Pugh class B or C. Cardiopulmonary bypass (CPB) was carried out at higher flow rate (2.4–3.2 L/min/m2), and hematocrit (25–30 %). Moderate and more tricuspid regurgitation were aggressively treated. Dilutional ultrafiltration was performed at the termination of CPB.

Results

Eighteen patients (mean age 70 years, male:female = 14:4) were identified. Twelve patients had hepatitis virus infection and 6 cases were alcohol-related. Fourteen patients were graded as Child-Pugh class B and 4 in class C. Seventeen patients underwent cardiac surgery with the use of cardiopulmonary bypass, and 1 patient underwent off-pump coronary artery bypass surgery. The overall mortality rate was 17 % (3 of 18). The cause of death was liver failure, esophageal variceal bleeding and bacteremia. The mortality of redo surgery was high (50 %). The incidence of postoperative liver failure was 11 % (2 of 18). Child-Pugh class or score was not correlated with hospital mortality. MELD score was significantly higher in hospital mortality (10.8 ± 4.0 vs. 17.3 ± 2.1, p = 0.001).

Conclusions

Although the mortality of redo surgery was high, cardiac surgery could be safely performed in selected patients with advanced liver cirrhosis.  相似文献   
67.
Objective:To develop surgical stents for cone-beam computed tomography (CBCT) 3-dimensional (3D) image-based stent-guided orthodontic miniscrew implantation and to evaluate its accuracy.Materials and Methods:Ten surgical stents were fabricated with stereolithographic appliances (SLAs) according to 3D CBCT image-based virtual implantation plans. Thirty self-drilling miniscrews were implanted at two to three positions on each side of the maxillary or mandibular posterior arches in three phantoms: 20 guided by 10 surgical stents in two phantoms (stent group) and 10 guided freehand in one phantom (freehand group). Six parameters (mesiodistal and vertical deviations at the corona and apex and mesiodistal and vertical angular deviations) were measured to compare variations between the groups.Results:No root damage was found in the stent group, whereas four of 10 miniscrews contacted with roots in the freehand group. In the stent group, deviations in the mesiodistal and vertical directions were 0.15 ± 0.09 and 0.19 ± 0.19 mm at the corona, respectively, and 0.28 ± 0.23 and 0.33 ± 0.25 mm at the apex, respectively; angular deviations in the mesiodistal and vertical directions were 1.47° ± 0.92° and 2.13° ± 1.48°, respectively. In the freehand group, the corresponding results were 0.48 ± 0.46 mm and 0.94 ± 0.87 mm (corona), 0.81 ± 0.61 mm and 0.78 ± 0.49 mm (apex), and 7.49° ± 6.09° and 6.31° ± 3.82°. Significant differences were found in all six parameters between the two groups (Student''s t-test, P < .05).Conclusions:3D CBCT image-based SLA-fabricated surgical stents can provide a safe and accurate method for miniscrew implantation.  相似文献   
68.
This article describes the foundation of a psychoanalytic institute in Japan and how its creation was based on the experience of training at the William Alanson White Institute. The process of starting a new institute is compared to the stages of growing plants, including planting seeds, sprouting, pruning, and transplanting. Creating an “ideal” institute requires a belief in education, the ability to find joy in relating to colleagues, and a capacity to deal with the evaluation process and with healthy tensions among subgroups.  相似文献   
69.
Ammonia, which is considered to be the main agent responsible for hepatic encephalopathy, inhibits oxidative glucose metabolism in the brain. However, the effects of ammonia on cerebral glucose metabolism in different brain regions remains unclear. To clarify this issue, we added ammonia directly to fresh rat brain slices and measured its effects on glucose metabolism. Dynamic positron autoradiography with [18F]2-fluoro-2-deoxy-d-glucose and 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium (WST-1) colorimetric assay revealed that ammonia significantly increased the cerebral glucose metabolic rate and depressed mitochondrial function, as compared to the unloaded control in each of the brain regions examined (cerebral cortex, striatum, and cerebellum), reflecting increased glycolysis that compensates for the decrease in aerobic metabolism. Pre-treatment with (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (MK-801), a N-methyl-d-aspartate (NMDA) receptor antagonist, significantly attenuated these changes induced by ammonia in cerebellum, but not in cerebral cortex or striatum. The addition of ammonia induced an increase in cyclic guanosine monophosphate (cGMP) levels in cerebellum, but not in cerebral cortex or striatum, reflecting the activation of the NMDA receptor-nitric oxide-cGMP pathway. These results suggested that NMDA receptor activation is responsible for the impairment of glucose metabolism induced by ammonia specifically in cerebellum.  相似文献   
70.
The aim of this study was to investigate mineralizing ability of a premixed calcium phosphate cement (premixed-CPC) compared to mineral trioxide aggregate (MTA) and zinc oxide eugenol cement (SuperEBA) in ROS17/2.8 cells. The measurements of cell proliferation, alkaline phosphatase (ALPase) activity and mineralized nodule formation in the presence or absence (control) of the test materials were performed using a cell culture insert method with the test materials placed on a porous membrane of culture plate insert. Mineralized nodules were detected by staining with alizarin red, and the calcium content of the mineralized nodules was determined quantitatively using a calcium assay kit. Premixed-CPC and MTA indicated significantly higher cell proliferation, ALPase activity, mineralized nodule formation, and calcium content in nodules than those of SuperEBA (p<0.05). The present results suggest that premixed-CPC has the same mineralizing ability as MTA.  相似文献   
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