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71.
Neurodegenerative disorders are characterized by disruptions to neuronal function and circuitry,leading to a variety of clinical syndromes depending on the affected neuroanatomic regions(Geula,1998).Many proteinopathies implicated in neurodegenerative diseases are characterized by the pathologic accumulation of proteins into inclusions that are initially deposited in specific areas of the brain and spread widely with disease progression.  相似文献   
72.
Objectives To compare objective voice measures of vocal stability during different speech tasks in women taking oral contraceptives to those in women not taking oral contraceptives. Methods Voice recordings obtained from 28 women, aged 20-30 years old, were used for the study. Eighteen of the women were taking some form of oral contraception at the time of the recording (OC women); ten women were not taking any oral contraceptive medication (NOC women). Measures related to pitch, vocal stability, and loudness were obtained from sustained vowel and paragraph reading tasks. Results The OC women demonstrated significantly higher pitch levels but lower values related to measures of vocal stability. Conclusions The use of oral contraceptives appears to exert a positive influence upon vocal fold function. Women taking oral contraceptives demonstrate higher pitch levels and greater stability during phonation than do women not taking oral contraceptives. This improvement in vocal function is contributed to the more stable hormonal environment that occurs with the use of oral contraceptives.  相似文献   
73.
Osteomyelitis: detection with US   总被引:2,自引:0,他引:2  
Abiri  MM; Kirpekar  M; Ablow  RC 《Radiology》1989,172(2):509-511
To evaluate the role of ultrasound (US) in the detection of osteomyelitis, the authors prospectively studied 48 patients clinically suspected of having osteomyelitis. A sonographic diagnosis was made if fluid was seen directly in contact with bone, without intervening soft tissues. Twelve of the 48 patients were subsequently found to have osteomyelitis. In 10 of them, US demonstrated abnormal fluid adjacent to the bone. This fluid was thought to represent an inflammatory exudate dissecting in a subperiosteal and/or extraperiosteal location. Eight of the 48 patients had soft-tissue fluid collections. The rest of the patients either had no abnormalities or had cellulitis. The authors conclude that US can be useful in the detection of osteomyelitis.  相似文献   
74.
研究发现银屑病皮损能够高度聚集原卟啉Ⅸ(PpⅨ,一种由5-ALA产生的内源性光源物质),但进行荧光诊断时却发现皮损内PpⅨ的分布存在差异,造成这种差异的原因目前尚不清楚。  相似文献   
75.
Objective: To investigate the diagnosis and surgical treatment of excessive lateral pressure syndrome of the patellofemoral joint caused by military training. Methods: Fifteen patients (patient group) and 18 healthy volunteers (control group) were involved in this retrospective study. Radiographs of the knee joints of all patients and volunteers were taken. The bone architecture was assessed, the trochlear angle, coincidence angle and patellofemoral joint index measured in both groups, and the resulting data compared. All 15 patients (17 knees) were treated by lateral collateral retinaculum release. Pre‐ and post‐operative pain was evaluated with a visual analog scale (VAS). Results: The differences between the two groups in coincidence angle (patient group: 7.67°± 5.81°; control group: ?2.2°±?2.71°) and patellofemoral joint index (patient group: 2.49 ± 1.40; control group: 1.25 ± 0.15) were statistically significant. Subchondral bone sclerosis and osteophytosis in the patellofemoral joint were more pronounced in the patient group than in the control group. The VAS was higher preoperatively (7.06 ± 0.85) than postoperatively (6 months postoperatively: 3.87 ± 0.24; 1 year postoperatively: 3.01 ± 0.17), and the differences between preoperative and postoperative were statistically significant. Conclusions: Apart from the case history, typical symptoms and physical signs, X‐ray examination is the most basic way to diagnose excessive lateral pressure syndrome of the patellofemoral joint, and the patellofemoral joint index is the most reliable for diagnosis. Lateral collateral retinaculum release with a small‐incision is an effective treatment for this disease.  相似文献   
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78.

Background

Wear particle-induced periprosthetic osteolysis that results in aseptic loosening is the most common cause of long-term failure after total joint replacement.

Materials and methods

Icariin (ICA), a flavonoid isolated from Epimedium pubescens, inhibits osteoclast formation, but its effects on wear particle-induced inflammatory osteoclastogenesis remains unclear. We investigated the role of ICA in the regulation of osteoclast differentiation in a murine macrophage cell line (RAW264.7), which is stimulated by titanium (Ti) particles and the receptor activator of NF-κB ligand.

Results

ICA effectively inhibited osteoclast formation and bone resorption in the differentiation medium. ICA (10−7 mol/L) significantly reduced the number of tartrate-resistant acid phosphatase-positive cells compared with the control, and significantly reduced the percentage of the surface covered by resorption lacunae. Quantitative real-time polymerase chain reaction analysis showed that ICA inhibited messenger RNA expression for the receptor activator of nuclear factor-κB, cathepsin K, tartrate-resistant acid phosphatase-positive, and matrix metalloproteinase-9 in RAW264.7 cells stimulated by Ti particles and receptor activator of NF-κB ligand. ICA also reduced pro-inflammatory cytokine expression of interleukin-1β and tumor necrosis factor-α in RAW264.7 cells cultured with Ti particles. In addition, incubation with cholecystokinin-8 showed that ICA had no toxic effects on RAW264.7 cells.

Conclusions

ICA possibly elicited inhibitory effects on inflammatory osteoclastogenesis induced by Ti particles, indicating that ICA may be useful for the prevention and treatment of wear particle-induced osteolysis.  相似文献   
79.

Aim

Ischemia-reperfusion injury (IRI) has been considered as the major cause of acute kidney injury and can result in poor long-term graft function. Functional recovery after IRI is impaired in the elderly. In the present study, we aimed to compare kidney morphology, function, oxidative stress, inflammation, and development of renal fibrosis in young and aged rats after renal IRI.

Materials and methods

Rat models of warm renal IRI were established by clamping left pedicles for 45 min after right nephrectomy, then the clamp was removed, and kidneys were reperfused for up to 12 wk. Biochemical and histologic renal damage were assessed at 12 wk after reperfusion. The immunohistochemical staining of monocyte macrophage antigen-1 (ED-1) and transforming growth factor beta 1 (TGF-β1) and messenger RNA level of TGF-β1 in the kidney were analyzed.

Results

Renal IRI caused significant increases of malondialdehyde and 8-hydroxydeoxyguanosine levels and a decrease of superoxide dismutase activity in young and aged IRI rats; however, these changes were more obvious in the aged rats. IRI resulted in severe inflammation and tubulointerstitial fibrosis with decreased creatinine (Cr) clearance and increased histologic damage in aged rats compared with young rats. Moreover, we measured the ratio of Cr clearance between young and aged IRI rats. It demonstrated that aged IRI rats did have poor Cr clearance compared with the young IRI rats. ED-1 and TGF-β1 expression levels in the kidney were significantly higher in aged rats than in young rats after IRI.

Conclusion

Aged rats are more susceptible to IRI-induced renal failure, which may associate with the increased oxidative stress, increased histologic damage, and increased inflammation and tubulointerstitial fibrosis. Targeting oxidative stress and inflammatory response should improve the kidney recovery after IRI.  相似文献   
80.

Objective

To compare the biomechanical and histological changes in a rabbit model after reconstructing the anterior cruciate ligament (ACL) with solely autologous tendon and with autologous tendon combined with the ligament advanced reinforcement system (LARS) artificial ligament.

Methods

Anterior cruciate ligament reconstruction was performed in 72 knees from 36 healthy New Zealand white rabbits (bodyweight, 2500–3000 g). The Achilles tendons were harvested bilaterally. The left ACL were reconstructed solely with autografts (autologous tendon group), while the right ACL were reconstructed with autografts combined with LARS ligaments (combined ligaments group). The gross observation, histological determination, and the tension failure loads in both groups were evaluated at 12 weeks (n = 18) and 24 weeks (n = 18) postoperatively.

Results

Gross examination of the knee joints showed that all combined ligaments were obviously covered by a connective tissue layer at 12 weeks, and were completely covered at 24 weeks. Fibrous tissue ingrowth was observed between fascicles and individual fibers in the bone–artificial ligament interface at both time points; this fibrovascular tissue layer localized at the bone–artificial ligament interface tended to be denser in specimens obtained at 24 weeks compared with those obtained at 12 weeks. The tension failure loads of the knees were similar in the autologous tendon group and the combined ligaments group at 12 weeks (144.15 ± 3.92 N vs. 140.88 ± 2.75 N; P > 0.05), and at 24 weeks (184.15 ± 1.96 N vs. 180.88 ± 3.21 N; P > 0.05).

Conclusion

Reconstructing the ACL in rabbits using autologous tendon combined with the LARS artificial ligament results in satisfactory biointegration, with no obvious immunological rejection between the autologous tendon and the artificial ligament, and is, therefore, a promising ACL reconstruction method.
  相似文献   
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