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31.
BACKGROUND CONTEXT: In patients with spinal osteoporosis, the early achievement and maintenance of a biological bond between the pedicle screw and bone is important to avoid screw loosening complications. There are few reports of in vivo investigations involving biomechanical and histological evaluations in the osteoporotic spine. PURPOSE: To evaluate the effect of hydroxyapatite (HA)-coating on the pedicle screw in the osteoporotic lumbar spine and to investigate the relationship between resistance against the screw pull-out force and bone mineral density (BMD) of the vertebral body. STUDY DESIGN/SETTING: Mechanical and pathological investigations in the lumbar spine. METHODS: Two 24-month-old female beagle dogs were fed a calcium-free dog chow for 6 months after ovariectomy (OVX). BMD (in g/cm2) was measured by dual energy X-ray absorptiometry at pre-OVX and 6 months after OVX. Pedicle screws were placed from L1 to L6 at 6 months after OVX. Twenty-four pure titanium cortical screws (Synthes, #401-114) were used as pedicle screws (Ti-PS). Of these, 12 screws had HA-coating (HA-PS). The HA-PS screws were inserted into the right pedicles and the Ti-PS were inserted into the left pedicles. Ten days after this procedure, the lumbar spines were removed en bloc for screw pull-out testing and histological evaluation. RESULTS: The mean BMD value of the lumbar vertebrae 6 months after the OVX was 0.549+/-0.087 g/cm2, which was significantly less than the pre-OVX mean BMD of 0.603+/-0.092 g/cm2 (p < 0.001). The mean resistance against the pull-out force for the HA-PS was significantly greater at 165.6+/-26.5N than in the Ti-PS (103.1+/-30.2N, p < .001). The histological sections in the HA-PS clearly revealed new bone bonding with the apatite coating but only fibrous tissue bonding in the Ti-PS. CONCLUSIONS: The results of this study showed that the resistance to the pull-out force of HA-PS is 1.6 times that of Ti-PS. Furthermore, HA-PS has superior biological bonding to the surrounding bone, as early as 10 days after surgery in this osteoporotic spine model. Thus, in patients with osteoporosis, coating of the pedicle screw with HA may provide better stability and bonding between the pedicle screw and bone in the early postoperative period.  相似文献   
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In order to elucidate the effectiveness of anti-mycotics in treating seborrhoeic dermatitis, an attempt was made to isolate Malassezia from seborrhoeic lesions of patients of seborrhoeic dermatitis. The results revealed that, in male patients, 46/49 cases were positive for Malassezia furfur on the face and 30/48 cases were positive for M. furfur on the scalp. In female patients, 7/13 cases were positive for M. furfur on the face, and 6/17 cases were positive for M. furfur on the scalp. Anti-mycotic agents were excellent in 50% and good in 31% of the spore-positive cases, yielding an overall efficacy rate of 81%. In contrast, the treatment of the face with vehicle alone showed only one excellent result out of 8 cases. Although clinical improvement was rapid on the side treated with a topical corticosteroid in the half-side-test, numerous fungal elements remained. While the improvement with anti-mycotic agents was slower than that with the corticosteroid, clinical improvement became evident by the third week of administration and fungal elements disappeared.  相似文献   
34.
Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line, using an EEA stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is a functionally acceptable option for low rectal cancer.  相似文献   
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36.
Three noninvasive image-diagnosing methods, computed tomography (CT), scintigraphy with201T1C1 and99mTcOh4 , and ultrasonography (US), were preoperatively performed on 50 patients with chronic renal failure and secondary hyperparathyroidism who underwent total parathyroidectomy and parathyroid autograft. The detection rates of the 3 methods on the 191 excised parathyroid glands were compared according to weight and location. CT detected 57.1% of all glands and 78.6% of 103 glands weighing over 500 mg. Scintigraphy detected 51.8% and 75.7%, and US detected 42.4% and 53.4%, respectively. The detection rate of upper glands was best with CT at 58.9% and 89.1%; that of lower glands was best with scintigraphy at 65.3% and 80.4%. Although the combination of the 3 methods diagnosed 69.6% and 89.5%, CT and scintigraphy, the best 2 combinations, visualized 67.5% and 88.3%.
Resumen Tres métodos diagnósticos no invasivos, la tomografía computadorizada (TC), la centelleografía con201T1C1 y99mTcO4 y la ultrasonografía (US) fueron realizados preoperatoriamente en 50 pacientes con falla renal crónica e hiperparatiroidismo secundario sometidos a paratiroidectomía y autotransplante paratiroideo. Las tasas de detección de los 3 métodos fueron comparados sobre las 191 glándulas paratiroideas resecadas en relación a los pesos y a los sitios de ubicación. La TC detectó el 57.1% del total de glándulas y el 78.6% de aquellas glándulas (103) con pesos superiores a 500 mg. La centelleografía detectó 51.8% y 75.7%, y la US 42.4% y 53.4% respectivamente. La tasa de detección para las glándulas superiores fue optima con TC, con 58.9% y 89.1%; la de las glándulas inferiores fue óptima con centelleografía, con 65.3% y 80.4%. Aunque la combinación de los 3 metodos diagnosticó el 69.6% y 89.5%, la TC y la centelleografía, la mejor de las combinaciones, visualizó el 67.5% y el 88.3% respectivamente.

Résumé Trois méthodes d'imagerie non invasives, la tomodensitométrie, la scintigraphie (avec T1C1210 et TcO4 99m), et l'ultrasonographie ont été pratiquées avant l'intervention chez 50 malades qui présentaient une insuffisance rénale chronique compliquée d'hyperparathyroïdisme secondaire et qui furent traités par parathyroïdectomie totale et autogreffe parathyroïdienne. Les taux de détection de ces 3 méthodes concernant 191 glandes parathyroïdes réséquées ont été évalués en fonction du poids et du siège des lésions. La tomodensitométrie a permis de découvrir 57.1% de toutes les glandes et 78.6% des glandes dont le poids dépassait 500 mg; la scintigraphie 51.8% et 75.7%; l'ultrasonographie 42.4% et 53.4%. Le taux de détection des glandes supérieures fut plus élevé avec la tomodensitométrie: 58.9% et 89.1%; celui des glandes inférieures le fut avec la scintigraphie: 65.3% et 80.4%. Si la combinaison des 3 méthodes permet le diagnostic dans 69.6% et 89.5% des cas la tomodensitométrie associée seulement à la scintigraphie donne des résultats très voisins, les taux respectifs étant de 67.5% et de 88.3%.


Presented at the International Association of Endocrine Surgeons in Paris, September 1985.  相似文献   
37.
Summary To study the effects of family history and reproductive, anthropometric, and dietary factors on the risk of breast cancer among low risk populations, we conducted a hospital-based case-control study involving 908 patients with breast cancer and their matched controls, in Japan. A positive family history of breast cancer significantly increased the risk of breast cancer (odds ratio = 1.52, 95% confidence interval: 1.14–2.03). The risk further increased with increasing number of family members affected. Obesity, single marital status, fewer births, a late childbirth, and less consumption of green-yellow vegetables and dairy products were also associated with an increased risk of breast cancer. These associations were independent in multivariate analyses. There was no increase in risk associated with consumption of high fat foods. When analyzed by menopausal status, the association with family history of breast cancer, especially in the first degree of relatives, was more evident for premenopausal breast cancer. The associations with obesity and lower consumption of dairy products were more pronounced for postmenopausal breast cancer, while those with lower parity and single marital status were stronger for premenopausal breast cancer.  相似文献   
38.
We assessed the local cerebral blood flow (LCBF) in 40 patients under fentanyl-diazepam anesthesia. The measurement of LCBF was made using 50%–70% stable xenon with 20 min of inhalation interval and a shuttle method for computed tomography imaging. All patients were anesthetized with 5.95±1.76 μg·kg−1 fentanyl and 0.22±0.07 mg·kg−1 diazepam under mechanical ventilation during CBF measurement. The values and distribution of LCBF on non-affected hemisphere appeared to be unaltered by fentanyldiazepam anesthesia. We also assessed the cerebral carbon dioxide reactivity in 6 patients. The cerebral carbon dioxide reactivity, expressed as percentage change in LCBF per unit change in arterial carbon dioxide partial pressure, was 5.39±1.07, and there were no significant differences of reactivity among regions studied. In conclusion, we showed reference values of LCBF and carbon dioxide reactivity, measured by stable xenon-enhanced computed tomography, in patients under fentanyl-diazepam anesthesia. Carbon dioxide reactivity was preserved in all regions including gray matter, white matter, and basal ganglia.  相似文献   
39.
A 77-year-old man, who underwent segmental pancreatectomy for intraductal papillary mucinous adenoma in 2001, was referred to our hospital with complaints of hematemesis and melena on January, 2004. Emergency upper gastrointestinal endoscopy showed a pulsating submucosal protrusion in the duodenal bulb, which was identified as a gastroduodenal arterial aneurysm measuring 1.5cm on abdominal CT imaging. Transcatheter arterial embolization of the aneurysm with metallic coils was successfully performed. Periodically repeated endoscopic examination has revealed the coils protruding into the duodenal lumen without any serious complication.  相似文献   
40.
Although the causes of stroke are diverse, thromboembolism due to a mobile aortic thrombus is rare. We describe a surgical case of acute massive pulmonary embolism after critical cerebral infarction associated with a mobile ascending aortic thrombus in a 52-year-old woman. Concomitant surgical removal of the aortic thrombus and pulmonary embolectomy was performed successfully, and the patient has been stable without recurrent thromboembolic complications after 18 months of follow-up.  相似文献   
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