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41.
Atlantoaxial fusion by transarticular screw fixation provides firm fixation, and good results have been reported. However, there are also problems, such as injury of the vertebral artery at the time of screw insertion. For accurate facet fusion, we developed a new hole-in-one guide for screw fixation and obtained good results with its use. In 60 adult subjects, we measured the antero-posterior and transverse axes and determined the center of the atlantoaxial surface and the insertion point of the screw in three dimensions on computed tomography scans. Based on these values, we measured the optimum screw insertion angle on sagittal and coronal planes, and the distance between the center and the posterior margin of the joint surface; our new hole-in-one guide was produced with these data. When the guide tip is determined to be located at the center posterior margin of the axial joint surface, and the guidewire insertion point is determined to be located at the center of the axial inferior facet immediately above the C2/3 joint, the guidewire is passed through the axial pedicle and the center of the atlantoaxial joint. Since April 1997, we have used this hole-in-one guide technique in eight patients with atlantoaxial instability. The screws passed the pars interarticularis and the center of the atlantoaxial joint in all patients with safety and accuracy. No complications associated with this technique occurred. Received: December 24, 1999 / Accepted: August 25, 2000  相似文献   
42.
This study was designed to determine the optimum treatment for a superficial esophageal cancer involving the mucosal or submucosal layer of the esophagus. The subjects were 150 patients with a superficial esophageal cancer who underwent endoscopic mucosal resection (EMR) or esophagectomy in Kurume University Hospital from 1981 to 1997. The mortality and morbidity rates, survival rate, and recurrence rate were retrospectively compared for (1) 35 patients who underwent EMR and 37 patients who underwent esophagectomy for a mucosal esophageal cancer and (2) 45 patients who underwent extended radical esophagectomy and 33 patients who underwent less radical esophagectomy for a submucosal esophageal cancer. Among the 72 patients with a mucosal cancer, lymph node metastasis/recurrence was observed in only one (1%); whereas of 78 patients with a submucosal cancer it was observed in 30 (38%). Among patients with a mucosal cancer the mortality and morbidity rates after EMR were lower than for those after esophagectomy. The survival rate after EMR was the same as that after esophagectomy. No recurrence was observed after either treatment modality. Among the patients with a submucosal cancer, the survival rate was higher and the recurrence rate lower after extended radical esophagectomy; than after less radical esophagectomy; the mortality and morbidity rates after extended radical esophagectomy were the same as those after less radical esophagectomy. Multivariate analysis demonstrated that the treatment modality (EMR versus esophagectomy) did not influence the survival of patients with a mucosal esophageal cancer, whereas it strongly influenced the survival of patients with a submucosal esophageal cancer. We concluded that EMR was the mainstay of treatment for a mucosal esophageal cancer, and extended radical esophagectomy was the mainstay of treatment for a submucosal esophageal cancer.  相似文献   
43.
A male newborn infant born at 38 weeks of gestation and weighing 2,660 g, was diagnosed as esophageal atresia. Although there was mild cyanosis at birth, his initial ultrasonographic examination performed by neonatologist showed normal anatomy of the heart. He underwent a surgical repair of esophageal atresia under general anesthesia. Anesthesia was induced with fentanyl and pancuronium, and maintained with sevoflurane and 60% oxygen. Frequent desaturation occurred during the procedure, requiring manual hyperventilation with 100% oxygen. Since blood pressure during the operation was unstable, volume loading with albumin was attempted. Further echocardiography was performed by pediatric cardiologist after going back to NICU. This revealed total anomalous pulmonary venous connection (TAPVC). He underwent cardiac surgery for repair of TAPVC on the next day. Although TAPVC was not preoperatively diagnosed regardless of results of echocardiogram, cyanosis and unstable blood pressure should be considered as signs of potential cardiac disease. Fluid restriction, higher hemoglobin, lower inspired oxygen and slightly higher carbon dioxide rather than albumin administration and hyperventilation should have been attempted during the esophageal repair.  相似文献   
44.
Purpose: Laparoscopic liver resection is safe, feasible and associated with less blood loss, shorter hospital stays and fewer postoperative complications in the working age patients with malignant liver tumors. However, it is still unclear if the elderly patients with malignant liver tumors would also benefit from that approach as the younger patients. So, the aim of the study was to compare the clinical outcomes of laparoscopic versus open liver resection for malignant liver tumors in elderly patients. Materials and Methods: Between March 2009 and July 2016, all elderly patients (≥70 years old) who underwent laparoscopic (n = 40) and open (n = 202) liver resection for malignant liver tumors were included. A one to one propensity score matching analysis was performed, based on 6 covariates, to decrease the selection bias. Results: There was no significant difference between the laparoscopic and open liver resection groups regarding the patient characteristics and tumor features. The operative time was comparable between both groups (Laparoscopic group 259 min vs Open group 308 min, p = .86), while patients who underwent laparoscopic liver resection had lower intraoperative blood loss (30 ml vs 517 ml, p < .0001), shorter hospital stays (10 days vs 23 days, p < .0001), and less overall morbidity (15% vs 38%, p = .04). The one-, three-, and five-year survival for patients with hepatocellular carcinoma was comparable between both groups (Laparoscopic group 96%, 74%, 47%, vs Open group 94%, 71%, 48%, p = .82), whereas The one-, three-, and five-year recurrence-free survival for patients with hepatocellular carcinoma was significantly higher in the laparoscopic group (88%, 60%, 60% vs 54%, 25%, 19%, p = .019). Conclusions: Laparoscopic approach for minor liver resection in elderly patients is safe and feasible with less blood loss, a shorter hospital stay, less postoperative complications and a better oncological outcome.  相似文献   
45.
Small polydisperse circular (spc) DNA was isolated from mouse thymocytes and cloned into the HindIII site of lambda vector Charon 7. Fifty-six recombinants from this spc DNA library were analyzed. R repeats, which were originally found near immunoglobulin genes, were enriched in spc DNA clones relative to their representation in the chromosome. In one clone, the R sequence was linked to Bam and MIF sequences and the contiguous arrangement was truncated from both ends. In another clone, composite Bam/R and R repeats existed as a pair in inverted repeat orientation. Truncation occurred from the 5' side without affecting the 3' ends. In both clones, short direct repeats flanked the repeated sequences. The possible role of R sequences in transposition and circular formation is discussed.  相似文献   
46.
Plasma lipid peroxidation in hyperlipidemic chickens   总被引:3,自引:0,他引:3  
Laying and genetically defective non-laying hens were evaluated for plasma lipid and plasma peroxidation levels. The non-layers developed extreme hyperlipidemia as well as greatly increased levels of lipid peroxidation. It was concluded that the concurrent presence of lipid peroxidation products must be considered when evaluating hyperlipidemic causes of atherosclerosis in the chicken.  相似文献   
47.
The drainage of the superficial middle cerebral vein (SMCV) is classified into four subtypes. The sphenobasal vein (SBV) drains from the SMCV to the pterygoid venous plexus at the temporal skull base. Epidural procedures in the standard anterior transpetrosal approach (ATPA) may damage the route of the SBV. We report a case in which modified surgical procedures via the ATPA were used to preserve the SBV. A 45-year-old man complained of right facial pain. Magnetic resonance images revealed a right cerebellopontine tumor suggestive of an epidermoid cyst. Right carotid angiography revealed that the SMCV drained into the pterygoid venous plexus via the SBV. The convexity dura mater of the temporal lobe was cut and the anterior part of the temporal lobe was retracted subdurally. The SBV was visualized from the subdural side. The basal dura mater of the temporal lobe posterior to the SBV was cut and the posterior part of the temporal lobe was retracted epidurally. After dissecting the dura mater medial to the greater petrosal nerve and to the edge of the petrous apex, the petrous apex was exposed and drilled out without injuring the SBV. The superior petrous sinus and the tentorium were cut. The tumor compressed the root exit zone of the trigeminal nerve. The tumor was grossly totally removed. The modified ATPA (epidural anterior petrosectomy with subdural visualization of the SBV) is effective in preserving the SBV.  相似文献   
48.
The effects of left ventricular assist system (LVAS) implantation on renal hemodynamics remains to be fully elucidated. We evaluated renal function and intrarenal blood flow in five advanced heart failure patients who had been supported with a Toyobo LVAS for bridge to heart transplantation. Renal function expressed as estimated glomerular filtration rate (eGFR) was calculated using the modified formula of Modification of Diet in Renal Disease. Mean blood velocities in the bilateral segmental arteries during systolic and diastolic perfusion were measured using duplex Doppler sonography, and renal vascular resistance (resistive index [RI]) of the segmental arteries was defined as (peak systolic velocity [PSV]-end-diastolic velocity [EDV])/PSV. All studies were performed before and after implantation (mean duration of support, 15.6±10.9 months). LVAS implantation significantly improved eGFR (42.7±7.9 to 64.1±16.3mL/min, P<0.05). Beat-by-beat measurements of heart rate did not change significantly. Mean PSV decreased significantly (38.2±8.9 to 28.3±2.2cm/s, P<0.05), and mean EDV increased significantly (8.3±3.2 to 11.3±1.3cm/s, P<0.05), and thus, mean RI was significantly improved (0.79±0.06 to 0.60±0.04, P<0.01). In conclusion, in advanced heart failure patients, pulsatile LVAS implantation is associated with improved renal function, and this improvement may be mediated in part through an improvement of intrarenal hemodynamics.  相似文献   
49.
Aortic arch replacement with proximal first technique.   总被引:2,自引:0,他引:2  
BACKGROUND: Deep hypothermic circulatory arrest (DHCA) without retrograde cerebral perfusion (RCP) has a strict time limit. We modified a surgical technique for anastomosis to shorten the period of DHCA and unilateral cerebral perfusion (UCP). METHODS: Between March 1993 and August 2001, retrospective analysis was done on 23 consecutive patients, who underwent aortic arch replacement with branches. The patients were divided into two groups: DHCA group and UCP group. The DHCA group, in which DHCA alone and without additional cerebral perfusion was performed, comprised of nine patients. Proximal aortic anastomosis was performed first during systemic cooling; then both the brachiocephalic artery and left carotid artery were reconstructed with the branches of the artificial graft during circulatory arrest; thereafter, cerebral and coronary perfusions were resumed. The UCP group, in which DHCA was not used but right hemisphere perfusion during deep hypothermia was performed when the origin of brachiocephalic artery was safely clamped, consisted of 14 patients. RESULTS: Mean time of DHCA was 18.8+/-4.2 minutes and that of right hemisphere perfusion time was 11.0+/-3.8 minutes, respectively. Twenty-one patients survived the surgery (91.3%), and two (8.7%) died during hospitalization. Transient cerebral complication occurred in four patients in the DHCA group and all recovered. Logistic regression analysis revealed that DHCA was the only parameter to significantly influence temporary neurological dysfunction. There was no other significant difference between the two groups. CONCLUSION: With our modified and simple surgical technique for aortic arch repair, we were able to successfully shorten the DHCA time and right hemisphere perfusion time. However, because DHCA was the only parameter to significantly influence temporary neurological dysfunction, some form of continuous cerebral perfusion at deep hypothermia may be a safer method to preserve cerebral function.  相似文献   
50.
BACKGROUND--Amyloidosis cutis dyschromica, a special type of primary cutaneous amyloidosis, is assumed to be a congenital disorder and sun exposure is thought to be the major causal factor. Herein we report a case of this rare disease and DNA repair characteristics of UV damages in the fibroblasts derived from the patient. OBSERVATIONS--A 24-year-old Japanese woman showed hyperpigmented and hypopigmented xerotic lesions in sun-exposed skin since she was 10 years old; deposits of amyloid material were detected in the papillary dermis. The fibroblasts were hypersensitive to UV-B, but not so sensitive to UV-C. Unscheduled DNA synthesis of the patient's cells after UV-C exposure was lower than that of normal cells at 3 hours and both reached the same level at 6 hours. After UV-B exposure, unscheduled DNA synthesis of the patient's cells was lower than that of normal cells at least until 6 hours after UV exposure. CONCLUSION--Although the origin of amyloidosis cutis dyschromica is unknown, hypersensitivity to UV-B with possible DNA repair defects is suggested to be the cause of this disease.  相似文献   
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