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1.
Different methods have been used throughout the years for syndesmotic injury but there is no consensus on the ideal treatment. Some methods are expensive and some have more complications. The aim of this study is to compare single suture endobutton with double suture endobutton and screw fixation for syndesmotic injury.Sixty nine patients with syndesmotic injury with fibular fractures whom were treated with a single interosseous suture endobutton system (ZipTightTM, Zimmer Biomet), a double interosseous suture endobutton system (ZipTightTM, Zimmer Biomet) and 1 syndesmotic screw (TST, Istanbul, Turkey) were included in this study. Functional and radiological results from patient records between 2015 and 2018 were retrospectively evaluated.Twenty patients were treated with the double interosseous suture endobutton, 23 were treated with the single interosseous suture endobutton, and 26 were treated with traditional AO screw fixation. Three patients from the screw fixation group (11.5%) required revision surgery (P < .05). All the radiologic and clinical outcomes were statistical similar in all 3 groups.Our findings showed that the interosseous suture endobutton system is at least as safe as the screw fixation technique for treatment of syndesmosis joint injuries and can be used as an alternative to the screw method. The interosseous suture endobutton system eliminates the need for a second surgery to remove the hardware, which minimizes the probability of re-diastasis. Since our results showed no statistical difference between single and double interosseous suture endobutton systems, the less costly single endobutton system may be the better alternative.  相似文献   
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OBJECTIVE: To evaluate the possible effects of sex and age on strength-duration time constant (SDTC). METHODS: The SDTC of 126 healthy volunteers was measured following stimulation of right median nerve at the wrist. Variations in values were evaluated according to sex and age. RESULTS: The SDTC was 438.6+/-114.5 micros in women and 396.2+/-90.3 in men (P=.023). In men, as age increased, so did SDTC. However, this was not true in women. Comparing the values of women and men, aged below 40, demonstrated a difference in excitability, confined to younger patients. CONCLUSIONS: As SDTC depends on the biophysical properties of the axonal membrane and can provide some information about Na(+) channel function, these data raise the possibility of a difference in Na(+) channel function between men and women and a difference in the conductance with age. SIGNIFICANCE: The age- and sex-related differences shown in this study suggest a possible biochemical or hormonal influence on axonal excitability.  相似文献   
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There is a large body of literature describing the causative role of oxidative stress mediated by increased levels of reactive oxygen species in the pathogenesis of cardiovascular disease such as atherosclerosis, hypertension, and restenosis after angioplasty. The positioning of a soft silicone collar around the rabbit carotid artery elicits intimal thickening. The findings from recent studies demonstrated that both intimal thickening and atherosclerosis lead to synthesis of inducible nitric oxide synthase, resulting in abundant amounts of nitric oxide. We investigated the effects of collaring and nicardipine treatment on the activities of antioxidant enzymes, superoxide dismutase and catalase, and total nitrite/nitrate levels, stable products of nitric oxide. Placing the collar increased the total nitrite/ nitrate levels and decreased superoxide dismutase activity in collared arteries. Treatment with nicardipine (20 mg/kg/day, s.c.) prevented enhanced nitric oxide degradation without affecting superoxide dismutase and catalase activities. Our results suggest that enhanced nitric oxide production and superoxide anion are generated in response to the collaring, resulting in oxidative stress within the segment in this model.  相似文献   
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OBJECTIVE: Hyperventilation and ischaemia increase axonal excitability by changing Na+ conductance in healthy subjects. However, the changes in excitability during and after ischaemia in diabetic patients are less than in healthy controls. This is known as ischaemic resistance. In this study, we investigated the effects of hyperventilation for 20 min on strength-duration time constant (SDTC) of motor axons of the median nerve of diabetic patients with polyneuropathy to determine whether diabetics are less affected by hyperventilation, a form of resistance similar to the ischaemic resistance of diabetics. METHODS: The SDTC of 14 diabetic patients with polyneuropathy and 10 healthy volunteers were measured following stimulation of right median nerve at the wrist prior to and after hyperventilation for 20 min. RESULTS: There was a significant increase in the SDTC in control subjects, but no significant change in the SDTC for patients with diabetic polyneuropathy. The score of the clinical response (paraesthesiae and carpopedal spasm) to hyperventilation of controls was also significantly greater in the controls than the patients. CONCLUSION: Hyperventilation for 20 min has little influence on SDTC in patients with diabetic polyneuropathy. SIGNIFICANCE: The 'resistance' of diabetic nerve is not confined to ischaemia but involves other manoeuvres that can alter axonal excitability.  相似文献   
6.
OBJECTIVES: Deep hypothermic circulatory arrest (DHCA) is commonly used during thoracic aortic surgery, and is initiated only after a sufficient degree of cerebral hypothermia is induced. The criteria for initiating DHCA vary among institutions: most centers use temperature criteria, some use electroencephalography, and a minority use jugular bulb oxyhemoglobin saturation SjO(2) criteria. The purpose of this study was to determine whether the use of SjO(2) monitoring to guide the onset of DHCA was associated with better post-operative neuropsychological outcome. METHODS: Sixty-one thoracic aortic surgical patients underwent both pre- and post-operative neuropsychological testing. Patients were divided into three groups: (1) those with SjO(2)> or =95% at DHCA onset; (2) those with SjO(2)<95% at DHCA onset; and (3) those without SjO(2) monitoring. RESULTS: There were no statistically significant differences in the incidence of post-operative decline in neuropsychological function among the three groups of patients. Patients in whom SjO(2) data were used to guide onset of DHCA had lower esophageal and bladder temperatures at that time compared with patients without SjO(2) monitoring. CONCLUSIONS: Monitoring of SjO(2) had no apparent effect upon post-operative neuropsychological outcome, and there were no trends in our small patient cohort suggesting differences that our study was not adequately powered to detect. Use of SjO(2) monitoring was associated with more profound hypothermia prior to DHCA due to more prolonged cooling in attempts to bring the SjO(2) above the 95% threshold. Using our institutional cooling protocol, SjO(2) monitoring does not appear to increase neuroprotection in patients undergoing DHCA for thoracic aortic repairs.  相似文献   
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Abstract Alzheimer's disease (AD) is defined pathologically by the presence of β-amyloid plaques, neurofibrillary tangles and extensive neuronal loss. Evidence indicates that increased DNA damage may contribute to neuronal loss in AD. Recently, it has been shown that in AD neurons have a reduced capacity for some types of DNA repair. Polymorphisms in DNA repair genes may be associated with differences in repair efficiency of DNA damage. Variants of several DNA repair genes, including the base excision repair gene XRCC1, have been described previously. We hypothesised that Arg194Trp polymorphism of XRCC1 gene may contribute to genetic susceptibility for AD. In order to test this hypothesis, we investigated Arg194Trp polymorphism at the XRCC1 gene in the DNA samples of 98 patients with AD and 95 healthy subjects. The frequency of the Trp allele was more pronounced among cases (11.2%) compared with controls (5.8%). On combining the homozygous and heterozygous variants of each codon, the variants seemed to be at twofold risk of AD, although the risk estimates were not statistically significant (OR=1.95, 95% CI 0.88–4.34, p=0.09). In addition, the 194Trp allele revealed a borderline significance (OR=2.05, 95% CI 0.96–4.37, p=0.056). According to our results, it may be speculated that the polymorphic variants of XRCC1 codon 194 have a role in the development of AD.  相似文献   
10.
The possibility for maxillary artery (MA) to petrous internal carotid artery (ICA) bypass was investigated. Five adult cadavers were dissected bilaterally. After zygomatic arch osteotomy, the coronoid process was sectioned at its base. An extensive infratemporal craniotomy was performed at the level of foramina ovale, rotundum and spinosum. The petrous portion of the ICA was exposed by drilling away the floor of the middle fossa, posterior to the foramen ovale and medial to the foramen spinosum. The MA was identified medial to the infratemporal crest and was followed in the pterygopalatine fossa, then transected at the origin of the infraorbital artery. The MA graft was brought posteromedially to reach the petrous ICA. The mean caliber of the MA before the origin of the infraorbital artery was 2.54±0.31 mm, 2.76±0.14 mm at the site of anastomosis, and 3.46±0.32 mm after giving off the middle meningeal artery. The average length of the MA between the middle meningeal artery and the infraorbital artery was 43.4±2.35 mm, and up to the site of anastomosis was 37.64±1.68 mm. We conclude that the length and diameter of the MA are sufficient for a tension-free anastomosis between MA and petrous ICA, and such a procedure could be used in the treatment of patients with tumors of the infratemporal fossa invading the high cervical ICA.

Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at
Étude anatomique des possibilités de by-pass entre la partie pétreuse de l'artère carotide interne et l'artère maxillaire
Résumé La possibilité d'un by-pass entre l'artère maxillaire et la partie pétreuse de l'artère carotide interne a été étudiée. Cinq cadavres adultes ont été disséqués des deux côtés. Après ostéotomie de l'arcade zygomatique, le processus coronoïde était sectionné à sa base. Une large craniotomie infra-temporale était effectuée au niveau du foramen ovale, du foramen rond et du foramen épineux. La partie pétreuse de l'artère carotide interne était exposée par fraisage du plancher de la fosse cérébrale moyenne, en arrière du foramen ovale et en dedans du foramen épineux. L'artère maxillaire était identifiée en dedans de la crête infra-temporale et suivie dans la fosse ptérygo-palatine, puis sectionnée à l'origine de l'artère infra-orbitaire. Le greffon d'artère maxillaire était transposé en dedans et en arrière pour atteindre la partie pétreuse de l'artère carotide interne. Le calibre moyen de l'artère maxillaire était de 2,54±0,31 mm à l'origine de l'artère infra-orbitaire, 2,76±0,14 mm au niveau de l'anastomose, et 3,46±0,32 mm après la naissance à l'artère méningée moyenne. La longueur moyenne de l'artère maxillaire entre l'artère méningée moyenne et l'artère infra-orbitaire était de 43,4±2,35 mm et au-delà du site d'anastomose était de 37,64±1,68 mm. Nous en avons conclu que la longueur et le diamètre de l'artère maxillaire était suffisant pour une anastomose sans tension entre l'artère maxillaire et la partie pétreuse de l'artère carotide interne. Ainsi, une telle technique pourrait être utilisée pour le traitement de patients porteurs d'une tumeur de la fosse infra-temporale envahissant la partie cervicale haute de l'artère carotide interne.
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