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991.
Introduction The purpose of this study was to compare the clinical and functional results and complications associated with staged bilateral total knee arthroplasty (TKA) performed 4–11 days apart during a single hospitalization in patients who were obese and patients who were not obese. Methods We retrospectively evaluated 48 (96 knees) patients who were obese and divided into two groups based on their body mass indices (BMI). Morbidly obese patients (group A1, BMI ≥ 40 kg/m2) consisted of 21 patients (42 knees), and obese patients (group A2, BMI ≥ 30 kg/m2) consisted of 27 patients (54 knees). The control group (group B, BMI < 30 kg/m2) consisted of 20 non-obese patients (40 knees), who were undergoing staged bilateral procedure within the same time frame. All patients had cemented TKAs with use of posterior cruciate sparing prosthesis without patellar resurfacing. If medically stable after the first arthroplasty the patients then underwent the second arthroplasty 4–11 days later. The data on major complications and minor complications were evaluated. Results Although, there was no statistically significant difference in overall complication rates in any of the groups, the non-obese group had fewer wound complications than the other groups (P > 0.05). No significant differences in preoperative or postoperative Knee Society score, and functional score could be demonstrated between the three groups (P > 0.05). Both obese and nonobese patients showed improvements in pain and function from pre-surgery to a minimum 2 years follow-up. Conclusion Results of bilateral staged TKAs in obese patients have low complication and high success rates and increased BMI has no negative effect on the early outcome. Bilateral staged TKA might be a good treatment alternative for the improvement of the patient’s quality of life and functional and clinical outcomes.  相似文献   
992.
Adenosine A(2A) receptors are predominantly expressed in the dendrites of enkephalin-positive gamma-aminobutyric acidergic medium spiny neurons in the striatum. Evidence indicates that these receptors modulate striatal dopaminergic neurotransmission and regulate motor control, vigilance, alertness, and arousal. Although the physiological and behavioral correlates of adenosine A(2A) receptor signaling have been extensively studied using a combination of pharmacological and genetic tools, relatively little is known about the signal transduction pathways that mediate the diverse biological functions attributed to this adenosine receptor subtype. Using a candidate approach based on the coupling of these receptors to adenylate cyclase-activating G proteins, a number of membranal, cytosolic, and nuclear phosphoproteins regulated by PKA were evaluated as potential mediators of adenosine A(2A) receptor signaling in the striatum. Specifically, the adenosine A(2A) receptor agonist, CGS 21680, was used to determine whether the phosphorylation state of each of the following PKA targets is responsive to adenosine A(2A) receptor stimulation in this tissue: Ser40 of tyrosine hydroxylase, Ser9 of synapsin, Ser897 of the NR1 subunit of the N-methyl-d-aspartate-type glutamate receptor, Ser845 of the GluR1 subunit of the alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid-type glutamate receptor, Ser94 of spinophilin, Thr34 of the dopamine- and cAMP-regulated phosphoprotein, M(r) 32,000, Ser133 of the cAMP-response element-binding protein, Thr286 of Ca(2+)/calmodulin-dependent protein kinase II, and Thr202/Tyr204 and Thr183/Tyr185 of the p44 and p42 isoforms, respectively, of mitogen-activated protein kinase. Although the substrates studied differed considerably in their responsiveness to selective adenosine A(2A) receptor activation, the phosphorylation state of all postsynaptic PKA targets was up-regulated in a time- and dose-dependent manner by treatment with CGS 21680, whereas presynaptic PKA substrates were unresponsive to this agent, consistent with the postsynaptic localization of adenosine A(2A) receptors. Finally, the phosphorylation state of these proteins was further assessed in vivo by systemic administration of caffeine.  相似文献   
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Background  Isolated tumor cells (ITC) are more likely to be identified when serial sectioning and immunohistochemical staining are used to evaluate sentinel lymph nodes (SLN). Our goal was to identify clinicopathologic features associated with ITC in patients undergoing sentinel lymph node dissection (SLND). Methods  We reviewed clinicopathologic data for 3557 patients with no clinical evidence of lymph node metastases undergoing SLND between November 1993 and March 2007. Patients were staged according to the 6th edition of the American Joint Committee on Cancer staging system, with metastasis ≤.2 mm classified as ITC. Results  A SLN was identified in 3475 patients (97.7%), including 2518 (72.4%) with negative nodes and 169 (4.9%) with ITC. A statistically significant association existed between lobular histology and the identification of ITC; 13.6% of patients with ITC had lobular histology versus 7.3% of patients with a negative SLN (P = .003). The presence of lymphovascular invasion (LVI) was also associated with ITC; 18.3% of patients with ITC had LVI in the primary tumor versus 8.5% of patients with a negative SLN (P < .001). No difference existed between patients with and without ITC with respect to T stage, grade, estrogen receptor, progesterone receptor, HER2/neu status, or biopsy method. Conclusion  The association between ITC and LVI, a known predictor of poor outcome, suggests ITC may have clinical relevance. The relationship between lobular histology and ITC is consistent with the known pattern of lobular metastases, which frequently present as small foci requiring immunohistochemistry for detection. Longer follow-up is needed to determine whether ITC have prognostic significance.  相似文献   
996.
Extensive calcification of mitral apparatus may preclude optimal valve repair, thus requiring debridement. We performed mitral valve replacement in a 55-year-old woman with a modified bileaflet preservation technique to avoid complications related to extensive debridement. Posterior transposition of the anterior leaflet as a buttress over the posterior ventricular wall provided extra support for the weakened tissues and covered the decalcified areas, which protected against debris embolism. This technique is safe and reproducible, especially for elderly patients who have complex calcification that requires extensive debridement, enables better preservation of ventricular function, and avoids disruption of the mechanical left ventricular wall.  相似文献   
997.
TNF and IL-1, which are produced from phagocytic cells, can produce a significant systemic inflammatory response independently by inducing systemic leukocyte and endothelial cell activation. These cytokines play a pivotal role in development of systemic inflammatory response after severe burn. Thalidomide has been shown to decrease the secretion of TNF from phagocytic cells, therefore suppression of TNF and IL-1 production from activated phagocytic cells might be a successful treatment modality for prevention of systemic inflammatory response following severe burn. To address this issue, we aimed to show whether thalidomide treatment decreased or suppressed plasma levels of TNF and IL-1 following burn in rats. Following the injury, 36 rats were randomly separated into two experimental groups at the third and seventh days. Rats in the experimental group had oral thalidomide (10mg/kg day) treatment for three and seven consecutive days whereas animals in control groups had no treatment. Thalidomide treatment decreased TNF and IL-1 significantly in both experimental groups at both the points (P<0.05). Although in this study we just showed inhibitory effect of thalidomide on plasma the level of TNF and IL-1, we speculate that thalidomide may have modulatory effect on the systemic inflammatory response after burn by decreasing plasma levels of TNF and IL-1.  相似文献   
998.
Prednisolone is a safe antiinflammatory agent for the treatment of inflammatory diseases. To improve the aqueous solubility of the drug and dissolution rate, the complexation of prednisolone with skimmed milk was studied. A physical mixture and solid dispersion of prednisolone with skimmed milk were prepared. The lyophilization method was used to prepare the solid dispersion. Detection of inclusion complexes was performed in the solid state using differential scanning calorimetry (DSC), powder X-ray diffractometry, and scanning electron microscopy. The diffractogram of the complex differed from that of the physical mixture, where the characteristic peaks of prednisolone, particularly at 23.9 degrees, 44.6 degrees, and 72.2 degrees (2 theta), nearly disappeared, indicating the formation of a true inclusion complex. These observations were in accordance with the results of the DSC analysis. Disappearance of the specific DSC peaks of the drug in the DSC curve of the solid dispersion showed that the drug interacts with the carrier.  相似文献   
999.
The effect of SO2 was examined on active avoidance learning, thiobarbituric acid reactive substances (TBARS), and the activities of Cu, Zn superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in young (3 months), middle-age (12 months ), and old (24 months) Swiss male albino rats. Ten ppm SO2 was administered to the animals of SO2 groups in an exposure chamber for 1 h/day x 7 days/week x 6 weeks while control groups were exposed to filtered air in the same condition. The most prominent effect of aging on active performance was also observed in the older group. SO2 exposure significantly decreased the active avoidance learning in the young group, but it had no effect on this parameter in the middle-aged and the older group compared with their corresponding control groups. SO2 exposure resulted in increased levels of Cu, Zn-SOD activity while decreased level of GSH-Px activity in all experimental groups compared with their corresponding control groups. CAT activities were unaltered. TBARS levels of all SO2 exposed groups were significantly increased compared with their respective control groups. In conclusion, results from the present research showed that SO2 exposure resulted in an increase in the lipid peroxidation and caused alterations in antioxidant enzyme activities. Additionally, SO2 exposure impaired cognitive function only in the young rats during the acquisition phase of active avoidance learning.  相似文献   
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