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SUMMARY A case congenital dislocation of both knees and dislocation of the left hip in an infant whose mother had a chronic amniotic fluid leakage after mid-trimester amniocentesis. 相似文献
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Advanced transcranial lesions may be successfully resected through a variety of contemporary skull base approaches. The identification and isolation of the internal carotid artery throughout its petrous course is essential in most of these surgical techniques. Anatomic landmarks normally used to identify this vital structure, however, may be severely distorted by tumor involvement or previous operative dissection. In an effort to define surgical landmarks that may be used in the identification of the petrous carotid artery, histologic sections of 100 temporal bones from adults were examined and microscopic measurements were recorded from the anatomic dissection of 10 fresh cadaver halfheads. On the basis of these studies, structures we have found useful in identification of the vertical petrous carotid artery during lateral skull base approaches include the: base of the styloid process, bony vascular crest, basal turn of the cochlea, medial wall of the eustachian tube, and the cochleariform process. Identification of the horizontal segment can be achieved by the preliminary delineation of the middle meningeal artery, greater petrosal nerve, tensor tympani muscle, mandibular and maxillary divisions of the trigeminal nerve, and the eustachian tube. Specific anatomic relationships with associated measurements are detailed and correlated with selected, illustrative cases. 相似文献
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C. Faldini M. Manca S. Pagkrati D. Leonetti M. Nanni G. Grandi M. Romagnoli M. Himmelmann 《Journal of orthopaedics and traumatology》2005,6(4):188-193
Abstract Complex tibial plateau fractures are a challenge in trauma surgery. In these fractures it is necessary to anatomically reduce
the articular part of the fracture and to obtain stable fixation. The aim of this study is to review the results of a surgical
technique consisting of fluoroscopic closed reduction and combined percutaneous internal and external fixation. Thirty-two
complex tibial plateau fractures in 32 patients were included. Twenty-one fractures were closed, 4 were open Gustilo grade
I, 3 were Gustilo grade II and 4 were Gustilo grade III. The mean age was 37.8 years (range 21–64 years). Surgery was performed
with patients in transcalcaneal traction and the knee flexed at 30° was used. Through a 1-cm incision centred over the tibial
metaphysis of the tibia, a 3.2-mm hole was drilled in the antero-medial tibial aspect. The tibial plateau fracture fragments
were elevated using either 1 or 2 curved Kirschner wires under fluoroscopy to control the reduction. Then the fragments were
fixed with 2 cannulated AO screws inserted through small incisions into the medial aspect of the tibial plateau. Knee rehabilitation
started postoperatively. Weight bearing started after 8–12 weeks depending upon the radiographic appearance. All external
fixators were removed in outpatient facilities. All patients were clinically and radiographically evaluated at a mean follow-up
of 48 months (range 38–57 months). Clinical results were evaluated according to the Knee Society clinical score. Average healing
time was 24 weeks (range 18–29 weeks). In 1 patient a non-union occurred. This patient was treated with open reduction and
plate fixation. In 2 patients a varus knee deformity occurred and a surgical correction was performed. There were no surgical
complications. Mean knee range of motion was 105° (range 75–125°) and mean Knee Society clinical score was 89. Twenty-five
results were scored as excellent, 4 good, 2 fair and 1 poor. Using this technique there is limited soft tissue damage and
virtually no periosteum damage to the fracture fragments. However anatomical reconstruction of the joint can be obtained.
Furthermore knee rehabilitation can be started immediately after surgery. We think that these factors were responsible for
the optimal clinical long-term results. 相似文献
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高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数 总被引:1,自引:0,他引:1
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。 相似文献
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石杉碱甲类似物的研究II.N-甲基吡啶酮石杉碱甲类似物的合成 总被引:4,自引:1,他引:3
石杉碱甲(1)是从中草药石杉属植物千层塔(Lycopodium serratum Thunb.)中分得的一种高效可逆的乙酰胆碱酯酶抑制剂,临床试验证实它对早老性痴呆症有显著疗效。本文报道N-甲基吡啶酮石杉碱甲类似物2和3的合成。2-甲氧基-5-甲氧羰基-11-亚甲基-5,9-甲撑环辛-7-烯并吡啶(9)在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮10,再用甲醇钠和碘甲烷甲基化得N-甲基吡啶酮11,11经碱性水解,Curtius重排和氨基的脱保护得N-甲基吡啶酮石杉碱甲类似物2。通过类似的途径从中间体2-甲氧基-5-甲氧羰基-7-甲基-11-酮-5,9-甲撑环辛-7-烯并吡啶(14)合成了类似物3。类似物2和3的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。 相似文献
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Short and long term effects of exercise training on the tonic autonomic modulation of heart rate variability after myocardial infarction 总被引:3,自引:0,他引:3
Malfatto G.; Facchini M.; Bragato R.; Branzi G.; Sala L.; Leonetti G. 《European heart journal》1996,17(4):532-538
We studied the effects of cardiac rehabilitation on the sympathovagalcontrol of heart rate variability in 30 patients after a first,uncomplicated myocardial infarction. Twenty-two patients completed8 weeks of endurance training (trained), while eight decidednot to engage in the rehabilitation programme for logisticalreasons, and were taken as untrained controls. Age, site ofinfarction, ejection fraction, ventricular diameter and stresstest duration were similar in the two groups at baseline. Heartrate variability was evaluated 4 weeks after infarction beforestarting rehabilitation, and repeated 8 weeks and one year laterin both trained and untrained patients. Measures of heart ratevariability, obtained from both time- and frequency- domainanalysis of a 15 min ECG recording in resting conditions, wereas follows: mean RR interval and its standard deviation (RRSD),the mean square successive differences (MSSD), the percent ofRR intervals differing >50 ms from the preceding RR (pNTN50),the low and high frequency components of the autoregressivepower spectrum of the RR intervals and their ratio (LF/HF).At baseline, heart rate variability was similar in trained anduntrained patients. In the short term (8 weeks after infarction),training increased RRSD by 25% (P<0·01), MSSD by 69%(P<0·01), pNN50 by 120% (P<0·01), and reducedLF/HF ratio by 30% (P<0·01). The effects persistedafter one year in trained patients. In untrained patients, theautonomic control of heart rate variability did not change 8weeks after myocardial infarction and was only slightly modifiedby time. Thus, exercise training, performed for 8 weeks aftera myocardial infarction, modifies the sympathovagal controlof heart rate variability toward a persistent increase in parasympathetictone, known to be associated with a better prognosis. This maypartly account for the favourable outcome of patients who undergorehabilitation. 相似文献