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1.
Anton A. Semenistyy Elena A. Litvina EA Anna G. Fedotova Chukwuweike Gwam Andrey N. Mironov 《Injury》2019,50(2):515-520
Background
Intramedullary nailing is considered a “gold standard” for treatment of tibial shaft fractures. However, some types of fractures are typically considered as “difficult for nailing”. This group includes the periarticular fractures, fractures of both bones at the same level, comminuted and segmental fractures of the tibia. Fixator-assisted nailing (FAN) is an effective method treatment of these types of fractures. The main requirements for the ideal reduction device are an ease of its installation and an ability of multiplanar fracture reduction. Fixator-assisted nailing (FAN) with the use of two perpendicular to each other monolateral tubular frames perfectly meets these requirements. In this study we present this new surgical technique and the analysis of first 30 cases.Methods
A prospective analysis was conducted for 30 patients with “difficult for nailing” tibial fractures treated with fixator-assisted nailing in our institution between September 1st, 2017, and March 1st, 2018. The duration of surgery and its different stages, the time of fluoroscopy, difficulties encountered during surgery, were analyzed. Clinical and radiological methods were used to evaluated reduction quality.Results
In all 30 cases the acceptable reduction was achieved. The mean duration of the surgical procedure was 73.7?±?3?min. The mean duration of fluoroscopy 85.9?±?4.8?s. In 7 cases we faced with technical difficulties, which were successfully addressed.Conclusion
The described technique of FAN is an effective method for the treatment of “difficult for nailing” tibial fractures. Future multi-centered studies with a larger number of patients are needed to validate our results. 相似文献2.
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Solitary bronchioloalveolar carcinoma: CT criteria 总被引:14,自引:0,他引:14
Kuhlman JE; Fishman EK; Kuhajda FP; Meziane MM; Khouri NF; Zerhouni EA; Siegelman SS 《Radiology》1988,167(2):379-382
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis. 相似文献
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Berbaum KS; el-Khoury GY; Franken EA Jr; Kathol M; Montgomery WJ; Hesson W 《Radiology》1988,168(2):507-511
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information. 相似文献
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The effect of external potassium on the elementary conductance of the ACh-induced potassium channel in the sino-atrial node 总被引:1,自引:0,他引:1
A. Noma W. Osterrieder W. Trautwein 《Pflügers Archiv : European journal of physiology》1979,381(3):263-269
The mechanism underlying the increase in the potassium conductance of the acetylcholine (ACh)-induced channel on increasing the extracellular potassium concentration (|K|0) was studied. The relaxation as well as the current fluctuations of the drug-induced current were measured at 3 and 12 mM |K|0 by conducting voltage clamp experiments in the rabbit sinoatrial node. The following results were obtained:
- The time constant of relaxation (τrelax) was not affected by changing |K|0. In both cases τrelax was about 130 ms at ?80 mV, 100 ms at ?40 mV and 60 ms at + 20 mV. It is, therefore, unlikely that the increase of the ACh-induced potassium conductance is due to a longer average open time of the drug-operated potassium channels.
- The chord conductance of the ACh-induced K current was increased by a factor of 1.7 at ?40 mV and by 1.5 at +10 mV on elevation of |K|0 from 3 to 12 mM.
- From the relation between the variance of the current fluctuations and the mean amplitude of the current the single channel conductance was determined to be 3.3 pS at 3 mM |K|0 and 5.9 pS at 12 mM |K|0, thus γ was increased by a factor of 1.7.
- From the power density spectrum an increase in the single channel conductance by a factor of 1.8 (at ?40 mV) could be calculated. The corner frequency was not affected.
- The increase in the potassium conductance, expected from the constant field equation when |K|0 is increased, agrees well with the experimental results.