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31.
We present a patient with vertebrobasilar insufficiency, with vertigo and horizontal nystagmus, induced by turning the head to the right. Angiography demonstrated transient occlusion of the left vertebral artery at the atlantoaxial joint during rotation of the head. The pathogenesis and angiographic findings are discussed.  相似文献   
32.
Two elderly women complaining of intermittent claudication complicated with persistent sciatic artery are herein reported. A direct femoral arteriogram showed hypoplasty of the superficial femoral artery and an unnatural anatomical relationship between the distal superficial femoral artery and the proximal popliteal artery, thus suggesting the presence of persistent sciatic artery. The diagnosis of persistent sciatic artery was finally made based on the aortography findings including the iliac arterial system and computed tomography (CT) scan. Magnetic resonance imaging (MRI) was helpful to demonstrate the entire image of this anomaly in cases with non-thrombolized sciatic artery. These diagnostic methods were useful in designing the optimal surgical strategy. The first case with a gluteal pulsating mass underwent exclusion of the persistent sciatic artery including the aneurysm through a retroperitoneal approach with a combination of femorotibial bypass, while the second case with thrombosed persistent sciatic artery only underwent femoropopliteal bypass. To recognize such a rare lesion, awareness of the differential diagnosis is important, and to provide appropriate treatment, an accurate whole image including adequate angiography, a CT scan, and magnetic resonance imaging is necessary.  相似文献   
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The clinical significance of ras oncogene expression in non-small cell lung cancer was evaluated in 116 surgically treated patients. Archival paraffin sections of the tumors were analyzed immunohistochemically using anti-ras p21 monoclonal antibody (MoAb) rp-35, and p21 staining was correlated with clinicopathologic parameters and survival. Positive reactions (+ and ++) were observed in 72.5% of the adenocarcinomas and 55.6% of the squamous cell carcinomas studied. The T1 tumors showed a ++ reaction less frequently than T2 and T3 tumors (P less than 0.05). Stage I tumors also were less reactive with MoAb rp-35 than tumors in more advanced stages (P less than 0.05). Survival analysis showed that patients with p21-negative tumors had significantly longer survival times (a 5-year survival rate of 64.1%) than those with p21 + tumors (38.0%, P less than 0.05) or those with p21 ++ tumors (11.5%, P less than 0.005). The significant correlation between p21 staining and patient survival was independent of histologic type, stage of disease, tumor or node status, and the resectability of tumors. On Cox's multivariate analysis, p21 staining was a major and independent prognostic determinant of survival. These results suggest that enhanced ras p21 expression may be one of the important biologic and clinical markers indicating the malignant potential of non-small cell lung cancer.  相似文献   
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A simplified technique of the liver transplantation under hypothermia has been studied in dog. An immersion hypothermia was used in both the donor and the recipient. The temperature of the graft at excision was lowered to 20 degrees C with supplemental use of topical cooling. The temperature of the recipient was lowered at 27 degrees C when the transplantation was attempted. Chlorpromazine and dopamine were employed beneficially in hypothermia. No perfusion or irrigation of the graft was performed. The use of heparin was avoided. Anastomoses were carried out in turn of the proximal vena cava, portal vein, distal vena cava and the hepatic artery with a stem shaped aorta. Reperfusion was established after the completion of anastomosis between the proximal vena cava and portal vein. The anhepatic phase of the recipient was uneventfully lasted without heparinization. All dogs, 5 out of 11 without early surgical troubles survived more than 5 days. Immunosuppressive therapy was not employed except one which died of pneumonia on the 19th postoperative day. Histologically, these dogs were free from ischemic injury and/or thrombotic lesion throughout transplantation procedure.  相似文献   
37.
To determine the healing potential and healing process of torn supraspinatus tendons, in situ hybridization was used to localize cells containing α1 type-I procollagen mRNA. Biopsy specimens of torn supraspinatus tendons from 19 patients with complete-thickness tears and 13 patients with incomplete-thickness tears were obtained during surgery. Four macroscopically normal supraspinatus tendons were obtained to serve as normal controls. Specimens were fixed in 10% buffered formalin and embedded in paraffin. A 22-mer oligonucleotide probe was labeled with digoxigenin and used as an in situ marker. The labeled cells were mainly composed of tenocytes and undifferentiated mesenchymal cells. In complete-thickness tears, the labeled cells at the proximal tendon stumps in the specimens that were obtained less than 4 months after trauma were significantly more abundant than in the specimens obtained 4 months or more after trauma. However, the number of labeled cells was maintained at the torn portion even in long-standing incomplete-thickness tears. The labeled cells at the margins of concomitant intratendinous extensions of the tears were detected even in the long-standing tears. The intratendinous extensions exhibited more labeled cell than were bursal-side or joint-side layers of the tendon substance in the incomplete-thickness tears (p < 0.05). The torn supraspinatus tendon may possess an intrinsic healing capability in the intermediate and late phases of tendon healing. Incomplete-thickness tears and concomitant intratendinous extensions can continue to rupture after the initial injury.  相似文献   
38.
Detection limit in low-amplitude EEG measurement.   总被引:1,自引:0,他引:1  
Electrocerebral inactivity for the determination of cerebral death is defined as no findings of EEG greater than the amplifier's inherent internal noise level when recording at increased sensitivity. A surface biopotential electrode contains two interfaces composed of skin gel (electrolyte) and gel electrode (metal), each forming a noise source. The power spectral density, S(f), of extremely low noise signals was obtained by means of autocorrelation and fast Fourier transformation. Interelectrode resistance, R(f), was measured with synchronous rectification. The formula of equivalent noise resistance R(n) = S(f)/4kT, where k is the Boltzmann constant and T is room temperature in Kelvin, gives a resistance that generates the thermal noise corresponding to the measured S(f). Rn/R is a parameter derived from normalization by R. When Rn/R = 1, measured noise contains thermal noise only. Meanwhile, Rn/R > 1 indicates presence of excess noise, such as 1/f, and tissue noise in addition to the thermal noise. Mean square root (Rn/R) of the scalp noise was 10.8 at 10 Hz, showing existence of excess noise. The study results suggest that it is necessary to take excess noise into consideration in the measurement of low-amplitude EEG for the determination of cerebral death.  相似文献   
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We report on a 66-year-old woman in whom GPi pallidotomy produced progressive and eventually complete relief of hemichorea/ballism (HCB) after a subthalamic hemorrhage. Although choreoballistic movements were unchanged during and immediately after the surgery, the symptoms were gradually improved and consequently abolished by 5 days postoperatively. HCB has never recurred up to the present (9 months follow-up period). This note is the first report describing detailed postsurgical process in HCB relief after pallidotomy.  相似文献   
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