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91.
To evaluate coronary hemodynamics and myocardial perfusion, left coronary digital subtraction angiography (DSA) and Tl-201 myocardial scintigraphy were performed in patients with syndrome X. The coronary circulation time (CCT) was significantly prolonged after the injection of isosorbide dinitrate and contrast medium i.c. Apical T1/2 was also prolonged on ergonovine malate provocation test. We suspected that the vascular response of the coronary peripheral artery was impaired, and microvascular spasm probably existed in patients with syndrome X. The prevalence of abnormal myocardial perfusion defect on exercise Tl-201 SPECT in syndrome X was very high, and coronary hemodynamics was significantly disturbed in the group of syndrome X with abnormal Tl-201 SPECT. Tl-201 lung/heart count ratio significantly increased in syndrome X on treadmill test. Because of this, exercise induced left ventricular dysfunction was suspected. We concluded that the main pathophysiological finding of impaired coronary circulation in syndrome X was microvascular spasm. 相似文献
92.
H Saito 《Kekkaku : [Tuberculosis]》1991,66(12):843-858
93.
K Takaoka T Nishina K Ohzono M Saito M Matsui N Sugano S Saito T Kadowaki K Ono 《Clinical orthopaedics and related research》1992,(277):121-127
Eighty-three hips in 66 patients with nontraumatic avascular necrosis of the femoral head (ANFH) showing evidence of severe collapse or secondary osteoarthritic changes were treated with surgical implantation of bipolar hip prostheses either with or without cement fixation of femoral stems. The cases were observed for more than three years (range, three to ten years seven months; average, five years seven months) and assessed in terms of functional and roentgenographic results. These data were compared with the results of classic hemiarthroplasties using fixed head prostheses (Austin-Moore-type with curved or straight stem) that were performed at the authors' institutions before 1980. The results confirm that the clinical outcome is improved with use of the bipolar prosthesis. Satisfactory results (a score of 80 or greater on a hip function scoring system proposed by the Japanese Orthopaedic Association) were maintained throughout the follow-up period in most cases (71 of 83 hips) with the bipolar prosthetic replacements. In a group of patients with unsatisfactory results (12 hips), proximal migration of prosthetic head was seen in two cases. The incidence of proximal migration of bipolar heads, including those exhibiting minimal movement, was significantly lower when compared with that observed in an Austin-Moore-type head-fixed prosthesis group (7/83 versus 12/19) during a comparable postoperative follow-up period. It is noteworthy that the proximal migration of the bipolar head was not progressive, and, in most cases observed more than five years, the cartilaginous spaces of acetabulum were preserved, whereas in the Austin-Moore-replaced group, the migration was evident and progression occurred within three years of surgery.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
94.
Livers from fed rats (180-240 g) were perfused noncyclically with a hemoglobin-free medium in vitro to determine whether vasoactive intestinal peptide (VIP) increases hepatic glucose production through a cAMP- or a Ca(2+)-dependent mechanism. Glucose output did not increase, but cAMP increased maximally during 10(-9) M VIP infusion. When VIP was perfused at 10(-8) M or more, glucose output increased dose dependently, whereas cAMP increased only a little during the VIP infusion, but increased greatly after the infusion. When Ca2+ was excluded from the perfusate, glucose output produced by 10(-8)-10(-7) M VIP was only 40% of that observed in the Ca(2+)-containing perfusion, and the increase in cAMP was abolished almost completely. By adding 10(-7) M A23187 for 10 min during the infusion of 10(-9) M VIP, cAMP, which increased with VIP alone, decreased during the A23187 infusion and increased again after the cessation of the A23187 infusion, whereas glucose output increased during the A23187 infusion. These results were similar to those observed with higher concentrations of VIP. When 10(-4) M isobutylmethylxanthine and 10(-8) M VIP were infused concurrently, cAMP increased rapidly during the infusion and decreased after the infusion. In conclusion, 1) glycogenolysis is produced by VIP through a Ca(2+)-dependent mechanism, rather than a cAMP-dependent one; and 2) the restriction of cAMP accumulation during the infusion of high concentrations of VIP is caused by Ca(2+)-induced phosphodiesterase activation. 相似文献
95.
Mitsuru Izumisawa DDS Masanori Shozushima DDS PhD Hirotaka Sato DDS PhD 《Oral Radiology》2003,19(2):47-55
Objectives It is known that, in fluorine-18 fluorodeoxyglucose Positron Emission Tomography (FDG PET) for the diagnosis of oral cancer,
FDG uptake may vary even among different cases of the same squamous cell carcinoma. However, the details of this phenomenon
have not yet been elucidated. In this study, we analyzed the relationship between histopathological findings in oral squamous
cell cancer and PET findings on FDG uptake.
Methods We examined 45 patients with oral squamous cell carcinoma who had undergone FDG PET before treatment. FDG uptake was assessed
by a standardized uptake value (SUV) calculated according to the PET-measured tissue concentration of FDG, the administered
dose of radionuclide, and the body weight of the patient. The relationship between the mean SUV and each of the following
parameters was examined: histological grade of malignancy, degree of cell differentiation, size and/or local extent of the
primary lesion, and cell density of the tumor.
Results The mean SUV of FDG uptake did not depend on the histological grade of malignancy or on the degree of cell differentiation,
but tended to be greater the larger the primary lesion. SUV also depended on cell density, increasing with the percentage
of tumor parenchyma.
Conclusions It is concluded that cancer cell density greatly influences the SUV of FDG, in that a tumor with fewer cellular elements in
cancer tissue tends to become a false negative. 相似文献
96.
H Sakugawa A Higashionna T Oyakawa K Kadena F Kinjo A Saito 《Gastroenterologia Japonica》1992,27(1):69-77
Primary Budd-Chiari syndrome, obstruction of the hepatic portion of the inferior vena cava (IVC), is a rare disorder, but relatively prevalent in the Far East, northern India and Africa. Ultrasound examination was carried out on 9 patients with primary Budd-Chiari syndrome. There were 5 men and 4 women aged 27-60 years. In all the 9 cases, the diagnosis was confirmed by cavography and liver histology. Moreover, 7 of the 9 subsequently underwent radical operation using a patch graft. Ultrasonic study showed several characteristic findings suggestive of the syndrome, and frequencies of the main findings were as follows: 1) an echogenic obstructing membrane; 22.2%, 2) segmental obstruction of the IVC; 77.8%, 3) occlusion of the major hepatic veins at the juxtacaval portion; 100%, 4) enlarged inferior right hepatic veins; 55.6%, 5) abnormal intrahepatic venous structures and collaterals; 88.9%. Of these findings, 5) was the most prominent and most characteristic in the diagnosis of the syndrome. It is necessary for early detection of this entity to evaluate carefully intrahepatic venous abnormalities and patency of either the IVC or major hepatic veins on ultrasonic examination. The careful examination for Budd-Chiari syndrome should be done in cases with cryptogenic liver cirrhosis, particularly in countries where the prevalence of the syndrome is high. 相似文献
97.
Wheat germ agglutinin-horseradish peroxidase conjugate was injected in the unilateral superior cervical ganglion (SCG), and the projection pathways of postganglionic sympathetic nerve fibers innervating the cochlea were traced in the rat. The labeled axons advanced along the internal carotid artery (ICA), and a few advanced caudally in the major petrosal nerve (MPN) and entered the facial nerve, while the majority ran rostral to the pterygopalatine ganglion at the point where they crossed the MPN in the carotid canal. The rest of the labeled fibers remained on the surface of the ICA and advanced to the cranial cavity. Most of the labeled fibers along the facial nerve joined the cochlear nerve and finally reached the osseous spiral lamina through the spiral ganglion. Some of the labeled fibers ran along the anterior inferior cerebellar artery from the basilar artery which was previously thought to have been the only pathway. We could not find any labeled fiber on the modiolar artery from anterior inferior cerebellar artery in the cochlea. These observations are consistent with our hypothesis that the sympathetic fibers innervating the neural tissues or related structures follow nerve fibers and meninges as matrices of projection pathways rather than arteries. 相似文献
98.
99.
The distribution of glucose-6-phosphate dehydrogenase (G6PD) activity has been studied by a copper ferrocyanide method in the adrenal cortex cells of a rat. The site of the G6PDH activity was close to the ribosome between the round mitochondria of zonas fasciculata and reticularis. 相似文献