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71.
An 80-year-old man underwent middle and lower lobectomy of the right lung to treat squamous cell carcinoma (SCC) (4 cm in diameter) originating from the right B4 bronchus. On the 4th postoperative day, a massive air leak from the thoracic drain was noted. At that time, a diagnosis of bronchial stump fistula was made on the basis of the bronchoscopic findings. Continuous thoracic drainage, aspiration of sputum via a tracheostomy and intravenous administration of antibiotics were performed immediately after the diagnosis. However, the patient's condition was complicated by aspiration pneumonia. On the 11th postoperative day, bronchoscopic procedure to close the bronchial fistula was performed via the tracheostomy. During this procedure, metallic coils were first inserted into the fistula to serve as the core for occlusion. Then, instead of directly infusing fibrin glue, several small beans-sized pieces of Surgicell cotton (Johnson & Johnson Co., Cincinnati, OH) soaked in fluid A (concentrated fibrinogen) and the same number of Surgicell cotton pieces soaked in fluid B (thrombin) were alternately inserted into the fistula, to allow closure of the bronchial fistula. After this procedure, the embolus created remained in place without being expectorated, and the aspiration pneumonia entered remission, allowing the patient to be discharged from the hospital on the 24th postoperative day. At preset, 14 months after surgery, the patient is in good condition. This technique allows simple and reliable closure of a fistula if a tracheostomy is available. It should be selected as a therapy of first choice when dealing with patients with a postoperative bronchial stump fistula in poor general condition. Patients undergoing right pneumonectomy or middle and lower lobectomy of the right lung should be considered as belonging to a high risk group for bronchial fistula and as requiring preventable measures (e.g., covering the stump with an intercostal muscle flap).  相似文献   
72.
Moderate hypothermia may have a beneficial effect on the neurological outcome. However, ischemic deterioration such as brain swelling during rewarming has been reported as a notable complication after successful therapeutic cerebral hypothermia. In this study, we investigated the effects of hyperbaric oxygenation during rewarming. Forebrain ischemia was produced in 24 gerbils and sham ischemia in 8 animals. Then ischemia-treated animals were divided into 3 groups, whole-body moderate hypothermia (31 degrees C for 60 min) and hyperbaric oxygenation (HBO2) (2- atmosphere absolute for 60 min using 100% oxygen) during rewarming group (n = 8), moderate hypothermia without HBO2 group (n = 8), and sham treatment without hypothermia and without HBO2 group (n = 8). Both the hypothermia group (77.9 +/- 48.1 neurons per mm, mean +/- SD) and hypothermia + HBO2 group (127.6 +/- 29.7 neurons per mm,) showed significant preservation of CA1 pyramidal neurons in the hippocampus compared to that in the sham treatment group (6.4 +/- 2.7) (p < 0.01). Furthermore, the hypothermia + HBO2 group showed significantly greater preservation of CA1 pyramidal neurons than the hypothermia group (p < 0.05). These results suggest that HBO2 during rewarming preserves the protective effect of hypothermia against ischemic neuronal damage.  相似文献   
73.
In order to examine the pathology in patients with obstructive sleep apnoea/hypopnoea syndrome (OSAHS), the nonlinear properties of respiratory movement and breath-to-breath variations during resting wakefulness with eyes closed was investigated. Recording of the respiratory movement using inductive plethysmography was performed on 14 patients with OSAHS and 13 control subjects for 2 h in the supine position during daytime. To calculate the correlation dimension (D2) for respiratory movement, an algorithm proposed by Grassberger and Procaccia was applied. The indices of breath-to-breath variations were estimated. To calculate D2 and breath-to-breath variations, two different segments were selected (200 s each). The value of D2 for respiratory movement in patients with OSAHS was significantly greater than that in control subjects. In the case of > or = 2.0 of D2 for respiratory movement, the sensitivity and specificity of detecting the presence of OSAHS was 85.7% and 76.9%, respectively. On the basis of breath-to-breath variations, only the coefficient of variation of expiratory time for respiratory movement in patients with OSAHS was significantly greater than that in the control subjects. In conclusion, the measurements of correlation dimensions for respiratory movement with a brief period during wakefulness may be a useful index for identifying patients with obstructive sleep apnoea/hypopnoea syndrome.  相似文献   
74.
We have investigated DNA synthesis in hepatocytes after orthotopic liver transplantation in four rat combinations--DA into DA (isogeneic), DA into PVG (allogeneic, nonrejector), DA into BN (allogeneic, rejector), and DA into (BN X PVG)F1 (allogeneic, intermediate nonrejector). The methods used were assay of thymidine kinase activity in graft homogenate and staining of hepatocytes in liver sections by an antibromodeoxyuridine monoclonal antibody. Both demonstrated increased DNA synthesis in grafts in all combinations except isogeneic, and showed that its intensity and timing paralleled the occurrence of the rejection reaction. The significance of hepatocyte regeneration after liver grafting is discussed.  相似文献   
75.
A 6-year-old boy was sent to us due to basal meningoencephalocele detected by MRI. He had had a past history of strabismus and morning glory syndrome since 6 months of age, as well as hypopituitary dwarfism since he was 3 years old. On admission, physical examination revealed hypertelorism and left coloboma. Laryngoscopic examination revealed a round mass covered by normal nasal mucose in the midline of the tegmen of the choana. X-ray tomogram and CT scan demonstrated an isodense mass protruding into the nasopharyngeal cavity through a bony defect of the sella turcica. Right carotid angiogram showed stenosis of the right internal carotid artery and abnormal fine vessels in the basal ganglia similar to basal Moyamoya network. There was an irregular filling of the right anterior cerebral artery. Left carotid angiogram showed an irregular filling of the left middle cerebral artery. MRI showed an anterior part of the third ventricle descending into, and the meningocele protruding into the nasopharyngeal cavity. It also showed a stalk extending from the hypothalamus into the meningocele, but the pituitary gland was not recognized. The meningocele was of the same signal intensity as CSF in both T1 and T2 weighted images. Growth hormone deficiency was confirmed by radioimmunoassay of the peripheral blood. An operation was scheduled transcranial to prevent snoring during sleep at age 9. The stalk was observed behind the chiasm during the operation, but a radical operation was not performed because of a possibility of postoperative hypothalamic-pituitary dysfunction. Transsphenoidal encephalocele is rare. So far as we could see, only 30 cases have been reported.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
76.
Cardiac output monitoring by impedance cardiography in cardiac surgery   总被引:1,自引:0,他引:1  
The cardiac output monitoring by impedance cardiography, NCCOM3, was evaluated in adult patients (n = 12) who were subjected to coronary artery bypass grafting. Values of cardiac output measured by impedance cardiography were compared to those by the thermodilution method. Changes of base impedance level used as an index of thoracic fluid volume were also investigated before and after cardiopulmonary bypass (CPB). Correlation coefficient (r) of the values obtained by thermodilution with impedance cardiography was 0.79 and the mean difference was 1.29 +/- 16.9 (SD)% during induction of anesthesia. During the operation, r was 0.83 and the mean difference was -14.6 +/- 18.7%. The measurement by impedance cardiography could be carried out through the operation except when electro-cautery was used. Base impedance level before CPB was significantly lower as compared with that after CPB. There was a negative correlation between the base impedance level and central venous pressure (CVP). No patients showed any signs suggesting lung edema and all the values of CVP, pulmonary artery pressure and blood gas analysis were within normal ranges. From the result of this study, it was concluded that cardiac output monitoring by impedance cardiography was useful in cardiac surgery, but further detailed examinations will be necessary on the relationship between the numerical values of base impedance and the clinical state of the patients.  相似文献   
77.
A 65-year-old man was referred to our hospital because of fever and abnormal shadow in the left lung. An aortogram revealed a large artery arising from the descending aorta supplying the left basal segment and, which then flowed into the pulmonary vein. This artery had an aneurysm and 30 mm in diameter. Bronchography showed compression of the left basal branch. A clinical diagnosis of an aberrant left pulmonary basal aneurysm arising from descending aorta was made, and left lower lobectomy was performed, because of the danger apprehension of the aneurysmal rupture. The procedure was successful. There are only 15 case reports of a systemic artery supplying the lung with normal bronchial branch in Japan. Differences of this anomaly from pulmonary sequestration were discussed.  相似文献   
78.
To clarify how the peripheral nerve adapts to elongation during gradual limb lengthening, electrophysiological and histomorphometric examinations were performed on the sciatic nerves in 18 rabbits. External fixators were used to lengthen the right femora by 30 mm (30%), at a daily rate of 0.5 mm (Group 1) or 2.0 mm (Group 2). Examinations were performed immediately after the limb lengthening procedure. Electrophysiologically, mild conduction slowing was observed in Group 1; a conduction block was evident in Group 2. Histologically, the mean diameter of myelinated fibers was unchanged in Group 1, but a significantly decreased diameter was observed in Group 2. Electron microscopy revealed that mild degenerative change of unmyelinated axons occurred sporadically in two cases in Group 2, but neither group showed evidence of thinning of myelin sheath of myelinated fibers. The mean internodal length (between nodes of Ranvier) of teased fibers was 1216+/-295 microm in the control contralateral side, 1484+/-347 microm in Group 1, and 1467+/-322 microm in Group 2. Thus the internodes were lengthened by 22.1% (Group 1) and 20.7% (Group 2) in comparison with those of the controls. Straightening of the geometry of paranodal myelin sheath was significantly correlated with the rate of distraction. These results indicate that myelinated nerve fibers adapt to gradual elongation by lengthening each Schwann cell body, not by proliferation of Schwann cells.  相似文献   
79.
80.
Screening of H-ras Gene Point Mutations in 50 Cases of Bladder Carcinoma   总被引:2,自引:0,他引:2  
Background Mutation converts the H-ras gene into an activated oncogene in about 10% of human bladder cancers. Codons 12 and 61 are the major "hot spots" for activation. A simple and accurate method to detect point mutations in these codons may be clinically useful for early diagnosis of bladder cancer.
Methods Bladder cancer samples from 50 patients, plus 10 samples of normal bladder mucosa, were analyzed for possible point mutation of the H-ras gene at either codon 12 or codon 61. The H-ras gene DNA segments that include these 2 codons were amplified by PCR methods, then the possible presence of a point mutation was evaluated at each codon by susceptibility of the respective DNA segments to digestion with the restriction enzyme and by dot blot hybridization assay. A bladder cancer patient who had an H-ras gene mutation was examined to see whether the mutation was also detectable in the cells released in the urine.
Results Definite or possible point mutations were found in 6 (1 2%) out of 50 bladder cancer patients, while no mutation was detected in normal mucosa. A point mutation could also be detected in cells isolated from the patient's urine sample.
Conclusion The prevalence of point mutations at codon 1 2 or codon 61 of the H-ras gene found in this study was similar to that previously estimated for human bladder cancer by DNA transfection assay. The method we have used for detecting point mutations of the H-ras gene provides a simple and highly accurate way to detect mutated cancer cells even in the urine. It may be clinically usable for early diagnosis of bladder cancer.  相似文献   
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