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191.
We have used the AO unreamed femoral nail for stabilization of impending and complete pathological fractures since March 1994.

27 patients with 30 pathological fractures (23) or impending fractures (7) of the femur were retrospectively analyzed. These included 18 subtrochanteric fractures, 11 shaft fractures and 1 distal fracture. The mean age of the patients was 68 (51-84) years. All patients were treated with a solid femoral nail inserted by an unreamed technique. The nail was inserted through a minimally invasive approach and with a median surgical time of 55 (35-70) minutes. A reconstructive proximal locking option (spiral blade) was used in 25 cases.

There were no intraoperative complications, no operative mortality. Reliable skeletal stability was obtained in all cases and most were able to mobilize early with minimum discomfort. 1 case was revised for a secondary fracture through a distal metastasis at 6 months. The median survival was 5 (2-9) months. Unreamed nailing with the AO solid femoral nail appears to be a good option for the stabilization of pathological femoral fractures.  相似文献   
192.
Despite its probable importance in health and disease, the elastic tissue in the trachea has rarely been investigated. In addition, various aspects of the trachealis muscle are controversial. The aim of this study was to clarify this clinically relevant anatomy. Ten cadaveric tracheobronchial specimens (age range 68–101 years; seven males; no major airway pathology) were qualitatively investigated by microdissection. Serial histologic sections from multiple sites in three specimens were analyzed after staining for elastin. Findings were correlated with observations from video tracheobronchoscopies. An extensive and prominent meshwork of elastic tissue was found within the trachea and bronchi. Elastic fibers were predominantly longitudinal and aggregated into discrete bundles within the membranous wall of the trachea and main bronchi; a discrete fibroelastic membrane bridging the membranous wall of the trachea; and vertical laminae connecting the ends of successive cartilages. The longitudinal elastic bundles continued into the segmental bronchi, becoming thinner and more circumferentially distributed. Trachealis consisted of a transverse layer of smooth muscle deep to the fibroelastic membrane of the membranous wall of the trachea, together with scattered longitudinal muscle bundles, mostly embedded within the fibroelastic membrane in the distal half of the trachea. In conclusion, there is an extensive but relatively neglected elastic framework within the tracheobronchial tree. This is likely to have major clinical relevance to the pathophysiology of respiratory disease and ageing. The trachealis muscle is more complex than previously stated. Clin. Anat. 22:689–697, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
193.
Genetic instability plays a crucial role in cancer development. The genetic stability of the cell as well as DNA methylation status could be modulated by folate levels. Several studies suggested associations between polymorphisms in folate genes and alterations in protein expression and variations in serum levels of the folate. The objective of this study was to investigate the effect of folate pathway polymorphisms on modulating genetic instability and lung cancer risk. Genotyping of 5 SNPs in folate pathway genes and cytokinesis‐blocked micronucleus cytome assay analysis (to determine the genetic instability at baseline and following NNK treatment) was conducted on 180 lung cancer cases and 180 age‐, gender‐, and smoking‐matched controls. Our results showed that individually, folate pathway SNPs were not associated with cytogenetic damage or lung cancer risk. However, in a polygenic disease such as lung cancer, gene–gene interactions are expected to play an important role in determining the phenotypic variability of the diseases. We observed that interactions between MTHFR677, MTHFR1298, and SHMT polymorphisms may have a significant impact on genetic instability in lung cancer patients. With regard to cytogenetic alterations, our results showed that lymphocytes from lung cancer patients exposed to the tobacco‐specific carcinogen 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanone [NNK] had considerably increased frequency of cytogenetic damage in presence of MTHFR 677, MTHFR 1298, and SHMT allelic variants. These findings support the notion that significant interactions may potentially modulate the lung cancer susceptibility and alter the overall the repair abilities of lung cancer patients when exposed to tobacco carcinogens such as NNK. © 2010 Wiley‐Liss, Inc.  相似文献   
194.
ObjectivesEpilepsy is a neurological disease characterized by sudden, abnormal, and hyper- discharges in the central nervous system (CNS). Valproic acid (VPA) is commonly used as a broad-spectrum antiepileptic therapeutic. However, in many cases, patients develop resistance to VPA treatment due to overwhelming oxidative stress, which in turn might be a major catalyst for disease progression. Therefore, antioxidants can potentially become therapeutic agents by counteracting reactive oxygen species (ROS)-mediated damage. The present study is aimed to evaluate the potential antiepileptic effect of astaxanthin (ASTA) in pentylenetetrazol (PTZ) induced epileptic model rats that are chronically treated with VPA for 8 weeks.MethodFifty-male Wistar rats were randomly divided into five groups: Non-PTZ group, PTZ, PTZ/VPA, PTZ/ASTA, and PTZ/VPA/ASTA treated groups.ResultsPTZ/VPA treated group showed a neuroprotective effect with improvement in antioxidant levels, behavioral test, and histopathological changes induced by PTZ. VPA also exhibited an anti-inflammatory effect as its treatment resulted in the reduction of tumor necrosis factor-α (TNF-α). ASTA exhibited an anticonvulsant effect and enhanced anti-inflammatory effect as compared to VPA. During the combined therapy, ASTA potentiated the antiepileptic effect of the VPA by reducing the oxidative stress and TNF-α as well as increased the glutathione (GSH) levels. Also, there were substantial improvements in the behavioral and histopathological changes in the VPA/ASTA treated group as compared to the VPA treated group.ConclusionASTA could have an antiepileptic and anti-inflammatory effect by reducing ROS generation. Therefore, co-administration of both the therapeutics (VPA/ASTA) has a synergistic effect in treating epilepsy and could potentially minimize recurrence and/or exacerbation of seizures.  相似文献   
195.
196.
Objectives:   To prospectively evaluate whether trans -rectal Three-Dimensional eXtended Imaging (3D XI) allows characterization of the prostate gland in cases of isolated benign prostate hyperplasia (BPH) so as to elucidate the motive for discrepancy of postvoiding residual urine.
Methods:   The study was conducted according to the standards of the local ethics committee. Patients gave informed consent. Disclosing the 3D XI display of the prostatic urethra and prostatic gland zones was a preliminary essential. The study included 113 men with a clinical diagnosis of BPH in whom transurethral resection of the prostate was planned. Patients aged from 52 to 75 years (mean 63). Other causes of infravesical obstructive uropathy and prostate neoplastic involvement were excluded. All patients were evaluated by three-dimensional Trans-Rectal Ultrasound using 3D XI methods. Patients were grouped according to the postvoiding residual urine volume into three groups, less and more than 100 mL and urine retention.
Results:   3D XI provided excellent resolution and diagnostic authority of prostate gland anatomy and for the appraisal of BPH morphology. The balance and type of nodular eruption proved responsible for the severity of symptoms aspires by extra-axial nodular effect upon the prostate urethra. The 3D XI analysis regarding the nodular stromal to glandular ratio compared to the histopathological results proved effectual in 98.3% of stromal-dominant, 100% in glandular-dominant and 93.3% in mixed type hyperplasia.
Conclusions:   The severity of symptoms among men with BPH showed an association with the nodular credence, highlighted by 3D XI as a supportive tool in characterizing BPH.  相似文献   
197.
198.
This paper presents a new online clustering algorithm called SAKM (Self-Adaptive Kernel Machine) which is developed to learn continuously evolving clusters from non-stationary data. Based on SVM and kernel methods, the SAKM algorithm uses a fast adaptive learning procedure to take into account variations over time. Dedicated to online clustering in a multi-class environment, the algorithm designs an unsupervised neural architecture with self-adaptive abilities. Based on a specific kernel-induced similarity measure, the SAKM learning procedures consist of four main stages: Creation, Adaptation, Fusion and Elimination. In addition to these properties, the SAKM algorithm is attractive to be computationally efficient in online learning of real-drifting targets. After a theoretical study of the error convergence bound of the SAKM local learning, a comparison with NORMA and ALMA algorithms is made. In the end, some experiments conducted on simulation data, UCI benchmarks and real data are given to illustrate the capacities of the SAKM algorithm for online clustering in non-stationary and multi-class environment.  相似文献   
199.
The effect of hypertonic glucose as a provocative test was studied in 51 patients with noncardiac chest pain, 15 patients with esophagitis, and 16 asymptomatic controls. It was compared to esophageal perfusion with 0.1 N HCl and saline and intravenous administration of 10 mg edrophonium. Continuous esophageal manometric recordings were performed at the time of testing. The patients' symptoms were monitored every minute. The effect of these solutions and edrophonium on lower esophageal sphincter (LES) pressure and amplitude of esophageal contractions was also evaluated. Esophageal perfusion with hypertonic glucose, saline, or acid had no significant effect on LES pressure or amplitude of esophageal contractions in most patients. Edrophonium, however, resulted in a significant rise in the amplitude of esophageal contractions and the LES pressure in all groups studied. Hypertonic glucose resulted in chest pain in 13.6% of patients with noncardiac chest pain and 20% of those with esophagitis, whereas edrophonium reproduced the pain in 38.7 and 37%, respectively. Our results indicate that hypertonic glucose is not effective as a provocative test for noncardiac chest pain nor does it contribute to the chest pain in esophagitis. They also had no significant effect on the amplitude of esophageal contractions or LES pressure. Edrophonium continues to be a relatively sensitive test for noncardiac chest pain.  相似文献   
200.
Sera of patients attending a genitourinary clinic, gynaecological clinic in Al Ali General Hospital, Riyadh, Saudi Arabia and from males and females without overt genital diseases were tested for the presence of antichlamydial antibodies using an immuno-fluorescence test. Antibodies for Chlamydia trachomatis were found in 66 (46%) of 145 male patients and 72 (35%) of 200 female patients attending a genitourinary clinic and gynaecological clinic respectively and in two (2%) of 100 men and in none of 100 women without genital diseases. These results suggest that the prevalence of chlamydial infection in Saudi Arabia among both men and women is high. Since serious complications can follow chlamydial genital infection, further work has to be done in this field.  相似文献   
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