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61.
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63.
Introduction. It has been reported that individuals with Autism Spectrum Disorder (ASD) have abnormal reactions to the sensory environment and visuo-perceptual abnormalities. Electrophysiological research has provided evidence that gamma band activity (30–80 Hz) is a physiological indicator of the coactivation of cortical cells engaged in processing visual stimuli and integrating different features of a stimulus. A number of studies have found augmented and indiscriminative gamma band power at early stages of visual processing in ASD; this may be related to decreased inhibitory processing and an increase in the ratio of cortical excitation to inhibition. Low frequency or “slow” (≤1HZ) repetitive transcranial magnetic stimulation (rTMS) has been shown to increase inhibition of stimulated cortex by the activation of inhibitory circuits.

Method. We wanted to test the hypothesis of gamma band abnormalities at early stages of visual processing in ASD by investigating relative evoked (i.e., ~100 ms) gamma power in 25 participants with ASD and 20 age-matched controls using Kanizsa illusory figures. In addition, we wanted to assess the effects of 12 sessions of bilateral “slow” rTMS to the dorsolateral prefrontal cortex on evoked gamma activity using a randomized controlled design.

Results. In individuals with ASD evoked gamma activity was not discriminative of stimulus type, whereas in controls early gamma power differences between target and nontarget stimuli were highly significant. Following rTMS individuals with ASD showed significant improvement in discriminatory gamma activity between relevant and irrelevant visual stimuli. We also found significant improvement in the responses on behavioral questionnaires (i.e., irritability, repetitive behavior) as a result of rTMS.

Conclusion. We propose that slow rTMS may have increased cortical inhibitory tone, which improved discriminatory gamma activity at early stages of visual processing. rTMS has the potential to become an important therapeutic tool in ASD treatment and has shown significant benefits in treating core symptoms of ASD with few, if any side effects.  相似文献   
64.
Contamination of the environment with antimony compounds may affect human health through the persistent exposure to small doses over a long period. Sixty growing male albino rats, weighing 43-57 grams, utilized in this study. The animals were divided into 3 groups; each of 20 rats: animals of group I served as control, animals of group II received 6 mg/kg body weight antimony trisulfide daily for 8 weeks with drinking water, and those of group III received the same dose by the same route for 12 weeks. The Malpighian renal corpuscles showed distortion, destruction and congestion of glomerular tuft, vacuoles in the glomeruli, peritubular haemorrhage, obliteration of Bowman’s space, and thickening with irregularity of Bowman’s membrane. The proximal convoluted tubules demonstrated patchy loss of their brush border, thickening of the basement membrane with loss of its basal infoldings, disarrangement of the mitochondria, pleomorphic vacuoles in the cytoplasm, apical destruction of the cells, apical migration of the nuclei, and absence of microvilli. On the other hand, peri-tubular hemorrhage, apical vacuolation, small atrophic nuclei, swelling of mitochondria, obliteration of the lumina, destruction of cells, and presence of tissue debris in the lumina, were observed in the distal convoluted tubules. The present work demonstrated the hazardous effect of antimony on the renal function as evidenced by the significant increase of the level of blood urea, serum creatinine, and serum sodium and potassium. In conclusion, this study proposed that continuous oral administration of antimony for 8 and 12 weeks has hazardous toxic effect on the structure and function of the kidney in growing albino rat. Based on the results of the present study, it is recommended to avoid the use of any drinking water contaminated with antimony compounds and forbidden its use in infants and children foods.  相似文献   
65.
The purpose of the present study was to identify proliferating cells in control versus experimental condyles two weeks following experimental Induction of anterior disk displacement (ADD) in the rabbit craniomandibular joint (CMJ). The right joint of 15 rabbits was exposed surgically and all diskal attachments were severed except for the posterior attachment. The disk was then repositioned anteriorly and sutured to the zygomatic arch. The left joint served as a sham-operated control. Ten additional joints were used as nonoperated controls. Mandibular condyles were excised two weeks following surgery and processed for proliferating cell nuclear antigen (PCNA) immunostaining. In control and sham operated condyles, PCNA was localized in the nuclei of chondroblasts of the reserve cell layer, chondrocytes of the upper hypertrophic layer and bone marrow cells of the subchondral bone. In contrast to control joints, the PCNA positive cells of the experimental joints were located throughout the osteoarthritic condylar cartilage. In addition, the percentage of PCNA positive cells of the osteoarthritic condylar cartilage was statistically significantly higher when compared to the control group, p < 0.05. It was concluded that surgical induction of ADD in the rabbit CMJ leads to an increase in mitosis of chondrocytes, which lead to cell proliferation and subsequent hyperplasia of the condylar cartilage.  相似文献   
66.

Purpose

By means of a multicentre retrospective study based on the failure of 418 aseptic unicondylar knee arthroplasties (UKA) our aims were to present the different types of revision procedure used in failed UKAs, to establish a clear operative strategy for each type of revision and to better define the indications for each type of revision.

Methods

Aseptic loosening was the principal cause of failure (n = 184, 44 %) of which 99 cases were isolated tibial loosening (23.5 % of the whole series and 54 % of all loosening), 25 were isolated femoral loosening (six and 13.6 %) and 60 were both femoral and tibial loosening (14.3 and 32.6 %). The next most common causes of failure were progression of arthritis (n = 56, 13.4 %), polyethylene wear (n = 53, 12.7 %), implant positioning errors (n = 26), technical difficulties (n = six) and implant failure (n = 16, 3.8 % of cases). Data collection was performed online using OrthoWave™ software (Aria, Bruay Labuissiere, France), which allows collection of all details of the primary and revision surgery to be recorded.

Results

A total of 426 revisions were performed; 371 patients underwent revision to a total knee arthroplasty (TKA) (87 %), 33 patients (7.7 %) were revised to an ipsilateral UKA, 11 (2.6 %) patients underwent contralateral UKA (ten) or patellofemoral arthroplasty (one) and 11 patients (2.6 %) underwent revision without any change in implants.

Conclusions

Before considering a revision procedure it is important to establish a definite cause of failure in order to select the most appropriate revision strategy. Revision to a TKA is by far the most common strategy for revision of failed UKA but by no means the only available option. Partial revisions either to an alternative ipsilateral UKA or contralateral UKA are viable less invasive techniques, which in carefully selected patients and in experienced hands warrant consideration.  相似文献   
67.

Purpose

This is a prospective study to evaluate the efficacy of elastic nails for the treatment of diaphyseal forearm fractures after failure of conservative management.

Method

In 35 patients with a mean age of 15.3 years (14–17 years), elastic nails were used for the treatment of diaphyseal forearm fractures after failure of conservative management. In 32 patients (91.4%), we performed closed reduction. In the remaining 3 (8.6%), closed reduction failed and an open reduction, through a minimal approach, was required before nailing.

Results

After a mean follow-up of 31 months (range 24–48 months), 20 (60%) patients had an excellent result 10 (34.3%) patients had a good result, and two (5.7%) patients had fair result. The mean time of union was 12 weeks (range 8–15). The mean time in cast was 8.5 weeks (range 7–11). Full range of elbow movement was regained in all cases; however, supination and pronation were limited in two patients. One patient had a superficial infection at the site of entry of the ulnar nail which was successfully treated with oral antibiotics and daily dressing. Neurapraxia affecting superficial branch of the radial nerve in one patient was resolved over a period of time. One case with partial rupture of extensor pollicus longus tendon was reported. There was one case of delayed union. No cases of refracture were reported after removal of the implant.

Conclusion

In adolescents, intramedullary fixation by using elastic nail plus cast immobilization provides effective treatment for diaphyseal forearm fracture when closed management has failed. However, it is of special importance to follow the right indication and to pay attention to correct technical procedure.  相似文献   
68.

Aim

The purpose of this study is to evaluate the clinical and radiological outcomes of cemented bipolar arthroplasty as a primary treatment for unstable intertrochanteric fracture in the elderly patients.

Methods

Twenty hips with unstable intertrochanteric fractures were followed for more than 2 years after cemented bipolar hemiarthroplasty. The mean age was 69 years, and the mean follow-up period was 30.5 months. We evaluated the results by Harris hip score, complications, and radiologic findings.

Results

At the last follow-up, the mean Harris hip score was 83.3 points. Radiologically, there was no case of osteolysis. All stems were stable without significant changes in alignment or progressive subsidence.

Conclusions

Bipolar hemiarthroplasty with calcar reconstruction is a good option for unstable intertrochanteric fractures in elderly patients with severe osteoporosis with strict indication selection. Longer-term studies with larger numbers of patients are required to address the issues of late complications.  相似文献   
69.
This study was conducted to evaluate the outcome of treatment for open fractures of the tibial plateau using external circular fixation combined with or without limited internal fixation. Twenty-five patients (16 males and 9 females) with open fracture tibial plateau were treated with circular external fixator with minimal internal fixation. The mean age of the patients was 36 years (range between 23 and 62 years). According to AO classification system, there was six (24 %) C1, eleven (44 %) C2, and eight (32 %) C3. According to Gustilo and Anderson classification, seven (28 %) were grade 1; nine (36 %), grade 2; six (24 %), grade 3b; and three (12 %), grade 3c. According to ASAMI score, Italy, the results were excellent in 8 (32 %) cases, good in 12 (48 %) cases, and fair in five (20 %) patients. The patients’ satisfaction was significantly related to the functional results (p < 0.05). Complications included skin gaping in one case 10 days postoperatively. Pin tract infection was seen in 20 % of cases, one case showed deep infection and no cases of septic arthritis. There is no correlation between the final outcome and articular depression (p > 0.05). Ilizarov external fixator provides acceptable outcomes but with a high rate of complication rate, typical of this type of fracture. It avoids extensive soft tissue dissection.  相似文献   
70.
Background: Few epidemiological studies of the prevalence of neuromuscular disorders have been undertaken. The aim of the study was to estimate the prevalence of the most common types of neuromuscular disorders in Qena governorate/Egypt.

Methods: A random sample was taken from 11 districts, involving 9303 inhabitants with 57.3% urban residents and 42.7% rural residence. Patients were diagnosed using a screening questionnaire for the diagnosis of neuromuscular disorders. All positive cases were referred to Qena University hospital where they underwent full clinical, electrophysiological, and laboratory investigations.

Results: Out of 9303 participants 448 cases were identified positive during survey. Four hundred and twenty-six cases proved to have neuromuscular disorders giving a crude prevalence rate (CPR) of 4.57%; 408 cases had definite neuropathy and 18 cases had muscular disorders equivalent to CPR of 4.39% and 193/105 respectively. There was a higher prevalence in the rural than urban population. The CPR of focal compression neuropathies was 1.8%, with the majority of cases having carpal tunnel syndrome (CPR = 1.67%). CPR of diabetic neuropathy was 1.67%. The CPR of compressive radiculopathy was 0.34%. Traumatic nerve injury had a CPR 0.06%. The lifetime prevalence of Bell’s palsy was 0.16%. Hereditary motor and sensory neuropathy had a CPR 0.08%. The CPR of idiopathic neuropathy was 0.09% and Infective Leprotic neuropathy was 0.04%. Five patients were diagnosed as having muscular dystrophy and another 5 patients had myotonia with CPR of 54/105 for each. Two cases of myasthenia gravis and another two cases with systemic myopathy were recorded giving a CPR of 21/105.

Conclusion: The overall CPR of neuromuscular disorders in the general population in Qena governorate/Egypt was higher than reported in other countries.  相似文献   
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