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101.

Purpose

The reduction of periosteal compression through the use of a locking plate may minimize disturbances of bone blood supply and may improve the rate of bone union. A single-centre, assessor blinded randomized controlled trial was conducted to compare the clinical effectiveness of a locking plate and a non-locking plate.

Methods

A total of 52 patients with AO/OTA 44B lateral malleolar fractures were included in this study. All patients underwent surgical fixation using a lag screw and neutralization plate. An identical treatment protocol was used in all patients, with exception of plate selection. The rate of radiographic bone union, defined as the complete disappearance of fracture lines confirmed through anteroposterior, lateral, and internal oblique views was compared at three, six, and 12 months following surgery. In addition, the Medical Outcomes 36-Item Short-Form Health Survey (SF-36) score, the time required for resolution of tenderness at the fracture site and the complication rate were evaluated.

Results

Twenty-three patients were randomly assigned to undergo fixation using a locking plate, and 29 patients were assigned to undergo fixation using a non-locking plate. Intention-to-treat analysis showed no difference in the radiographic bone union rate of fibula, SF-36 score, the time for resolution of tenderness at the fracture site and complication rates.

Conclusion

No differences were observed in patients with AO/OTA 44B lateral malleolar fractures undergoing fixation with a locking versus non-locking neutralization plate.  相似文献   
102.

Purpose

Hyponatremia in hospitalized patients has been reported to be associated with in-hospital mortality. We studied patients treated at our hospital for hip fracture regarding the factors related to hyponatremia at admission.

Methods

Among 580 patients aged 60 years or above who were admitted to our hospital since January 1997 for treatment of hip fracture, 512 patients (110 males, 402 females) from whom serum sodium level at admission was available were studied. In 512 patients, the age at injury ranged from 60 to 103 (mean 82.6) years. Fracture types were femoral neck fracture in 191 patients, and trochanteric fracture in 321. These patients were divided into two groups by the blood sodium level at admission: a hyponatremia group with sodium levels lower than 135 mEq/L, and a normonatremia group with sodium levels within normal range. The age, gender, fracture type, residence before injury, pre-injury walking capability, anemia at admission, liver function, kidney function, inflammatory status, urinary glucose status, lung disease, ECG abnormality, systemic chronic disease, status of dementia, treatment modality, hospital stay (days), and in-hospital death were investigated. First a univariate study was conducted to identify the factors that differ significantly between the two groups. Then multivariate analysis was conducted using the parameters with significant difference as independent variables

Results

Hyponatremia was found in 49 of 512 (9.6 %) patients. In univariate analyses, six factors (age; residence before injury; anemia; dementia; treatment modality; in-hospital death) were significantly different between the hyponatremia group and normonatremia group. Multivariate analysis identified in-hospital death [odds ratio (OR) = 3.64, p = 0.035] and age (OR = 1.05, p = 0.029) as independently associated with hypernatremia.

Conclusion

Hyponatremia at admission is prevalent in old aged patients with fracture, and is related to in-hospital death.  相似文献   
103.
The effect of Nizofenone (Y-9179), a verebral protective agent, on delayed ischemic neurological deficits following subarachnoid hemorrhage (SAH) due to aneurysmal rupture was investigated by a cooperative double-blind clinical trial. Delayed ischemic neurological deficits following SAH are closely associated with the occurrence of vasospasm, and the effectiveness of any cerebral protective agent depends on sufficient coverage by the drug over the period around the onset of ischemic insult. Therefore, the study was designed so that the effect of Nizofenone could be analyzed in terms of these two factors.

In patients admitted within day 9 of SAH, drug administration was immediately initiated and continued for 5 days. When delayed ischemic neurological deficits occurred, angiography was carried out to confirm the presence of vasospasm, and then drug administration was extended for an additional 5 days. Ten of the 100 cases enlisted in the study were excluded prior to code-breaking because of the occurrence of severe complications not related to vasospasm.

Out of the 42 cases of the Nizofenone group and 48 of the placebo group, 25 and 29 developed vasospasm, respectively. Thus Nizofenone did not prevent vasospasm. Of the 25 cases of the Nizofenone group with vasospasm, 13 cases received sufficient drug coverage around the onset of vasospasm. The placebo group, the total Nizofenone group, and the Nizofenone group with sufficient drug coverage were stratified according to the occurrence of vasospasm. The disability status index one month after admission and the neurological functions, such as motor and speech functions, of each group were then compared. In patients who developed vasospasm, only the Nizofenone group with sufficient drug coverage had a significantly better outcome than the placebo group (p < 0.05). No particular side effect of Nizofenone was observed.

Thus, the results indicate that Nizofenone may be useful in the therapy of delayed ischemic neurological deficits following SAH, although the effect of the drug may be considerably influenced by the timing of its administration.  相似文献   
104.
To identify fetuses at high risk of poor neurological outcomes using a novel ultrasound evaluation system. We assessed an ultrasound evaluation system based on our previous findings, consisting of screening for decreased or lack of fetal movements, abnormal patterns of fetal heart rate, congenital CNS malformations, polyhydramnios of unknown cause, and a “brief ultrasound evaluation” of fetal brain functions, including movement of extremities, breathing movements, ultradian rhythm, REM period, and NREM period. We then assessed the correlation between fetal brain functions and neurological outcomes in infancy (MR, CP, and low Developmental Quotient). During screening, we prospectively evaluated 4978 fetuses receiving prenatal and intrapartum management between January 2000 and December 2009 in our hospital that were later delivered between 32 and 41 weeks’ gestation and identified 93 cases as suspicious for impairment. Of the 93 fetuses, 26 underwent the second step of brief ultrasound examination at 35–40 weeks’ gestation. Our findings revealed that this method was adequately sensitive (80%) and specific (88%) in identifying neurological impairment. We concluded that this method was mainly useful in the clinical setting for establishing the first indication for fetal CNS examination for functional impairment, rendering it suitable for clinical application.  相似文献   
105.
The purpose of this study was to develop and report upon a methodology for a non-linear capacity 3D modeling finite element analysis evaluating the loading behavior of different partial denture designs. A 3D finite element model using human CT data was constructed. An original material constant conversion program was implemented in the data simulation of non-linear tissue behavior. The finite element method material properties of residual ridge mucosa were found to have seven material constants and six conversion points of stress values. Periodontal tissues were found to have three constants, and two conversion points. Three magnetic attachment partial denture designs with different bracing elements were evaluated. Technical procedures for finite element model simulation of nonlinear tissue behavior properties evaluating the oral behavior of prosthetic device designs are reported for prosthodontic testing. The use of horizontal cross-arch bracing positively impacts upon the comparative stability of the partial denture designs tested.  相似文献   
106.
Hyponatremia is the most common clinical electrolyte disorder. Once thought to be asymptomatic in response to adaptation by the brain, recent evidence suggests that chronic hyponatremia may be linked to attention deficits, gait disturbances, risk of falls, and cognitive impairments. Such neurologic defects are associated with a reduction in quality of life and may be a significant cause of mortality. However, because underlying diseases such as adrenal insufficiency, heart failure, liver cirrhosis, and cancer may also affect brain function, the contribution of hyponatremia alone to neurologic manifestations and the underlying mechanisms remain unclear. Using a syndrome of inappropriate secretion of antidiuretic hormone rat model, we show here that sustained reduction of serum sodium ion concentration induced gait disturbances; facilitated the extinction of a contextual fear memory; caused cognitive impairment in a novel object recognition test; and impaired long-term potentiation at hippocampal CA3–CA1 synapses. In vivo microdialysis revealed an elevated extracellular glutamate concentration in the hippocampus of chronically hyponatremic rats. A sustained low extracellular sodium ion concentration also decreased glutamate uptake by primary astrocyte cultures, suggesting an underlying mechanism of impaired long-term potentiation. Furthermore, gait and memory performances of corrected hyponatremic rats were equivalent to those of control rats. Thus, these results suggest chronic hyponatremia in humans may cause gait disturbance and cognitive impairment, but these abnormalities are reversible and careful correction of this condition may improve quality of life and reduce mortality.  相似文献   
107.

Background

Determination of daily protein intake in the management of chronic kidney disease (CKD) requires precision. Inaccuracies in recording dietary intake occur, and estimation from total urea excretion presents hurdles owing to the difficulty of collecting whole urine for 24 h. Spot urine has been used for measuring daily sodium intake and urinary protein excretion.

Methods

In this cross-sectional study, we investigated whether urea nitrogen (UN) concentration in spot urine can be used to predict daily protein intake instead of the 24-h urine collection in 193 Japanese CKD patients (Stages G1–G5). After patient randomization into 2 datasets for the development and validation of models, bootstrapping was used to develop protein intake estimation models.

Results

The parameters for the candidate multivariate regression models were male gender, age, body mass index (BMI), diabetes mellitus, dyslipidemia, proteinuria, estimated glomerular filtration rate, serum albumin level, spot urinary UN and creatinine level, and spot urinary UN/creatinine levels. The final model contained BMI and spot urinary UN level. The final model was selected because of the higher correlation between the predicted and measured protein intakes r = 0.558 (95 % confidence interval 0.400, 0.683), and the smaller distribution of the difference between the measured and predicted protein intakes than those of the other models.

Conclusion

The results suggest that UN concentration in spot urine may be used to estimate daily protein intake and that a prediction formula would be useful for nutritional control in CKD patients.
  相似文献   
108.
109.
Knee osteoarthritis (OA) is becoming more prevalent worldwide due to increases in the numbers of elderly and obese patients. Currently, pharmaceutical medicines used for the treatment of OA are for symptomatic therapy and therefore new therapeutic agents are needed. Kaempferia parviflora (KP) is a plant growing naturally in Southeast Asia and has various pharmacological effects including an anti-inflammatory effect, but no effect on OA has yet been reported. We therefore conducted a search for the effects KP and the active components of KP extract (KPE) exert on OA as well as its mechanism of action. Results from a study of KPE using the monoiodoacetic acid rat OA model revealed that KPE reduced the pain threshold and severity of osteoarthritic cartilage lesions. The mechanism of action and active components were then investigated using IL-1β-treated human knee-derived chondrocytes. KPE, as well as 5,7-dimethoxyflavone and 5,7,4′-trimethoxyflavone, which are key constituents of KPE and highly absorbable into the body, reduced the expression of matrix metalloproteinases (MMPs), which are the main extracellular matrix enzymes that degrade collagen within cartilage. As mentioned above, KPE acted to suppress OA and 5,7-dimethoxyflavone and 5,7,4′-trimethoxyflavone were shown to be involved as part of KPE’s mechanism that inhibits MMPs.  相似文献   
110.
PURPOSE: The use of osseointegrated implants for maxillofacial prostheses reduces the need for adhesives, provides for a more stable and more esthetic prosthesis with thinner margins, and results in increased patient acceptance and confidence. The purpose of this study was to compare the retention and load transfer characteristics of differently designed implant-retained auricular prostheses. MATERIALS AND METHODS: A photoelastic model was fabricated of the auricular-temporal region of a human skull. Craniofacial implants 3.75 mm in diameter and 4 mm long were embedded in locations typically selected to retain auricular prostheses. Two retention mechanisms were evaluated on the implants: a Hader bar with 3 clips and the use of 3 Locator attachments. The retentive capacity of the prostheses was determined on an Instron test machine. Initial retention and changes with multiple removals were examined. Dislodgment forces were applied to each retentive device in the field of a circular polariscope. Resulting stresses were monitored and recorded photographically. RESULTS: The highest initial retention demonstrated by the Locator device was 12.4 +/- 0.9 lb, and the highest retention value for the Hader bar with clips was 7.5 +/- 1.1 lb. All attachments decreased in retention after multiple removals. The Locator devices produced higher peri-implant stresses compared to the Hader bar-with-clips design. CONCLUSIONS: Since higher retention is associated with higher stresses, results of this study suggest that a balance between retention and stress production is necessary in selecting a retention mechanism for the specific requirements of the patient being treated. The Locator attachment was correlated with higher retention values as well as with higher peri-implant stress compared to the Hader bar-and-clip attachment design. Retention decreased and then stabilized after multiple  相似文献   
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