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991.
BACKGROUND: It remains very difficult to clarify the spatial arrangement of the branches of the pancreatic ducts in the head of the pancreas despite recent progress in diagnostic imaging techniques. METHODS: We minutely dissected the head region from 15 cadavers after injection of silicone rubber into the ducts through the papilla of Vater to investigate the distribution of these ducts. RESULTS: We found that the branches that drained the uncinate process not only joined the main pancreatic duct but also constantly joined the accessory pancreatic duct. In addition, the branches of the uncinate process that joined the accessory duct ran anterior to those to the main duct. We classified the arrangement of the pancreatic ducts into type 1 (10 cases) and type 2 (5 cases) on the basis of the pattern of the branches of the uncinate process. The distance from the papilla of Vater to the junction of the main and accessory pancreatic ducts in type 1 (> 23.0 mm) was significantly longer than that in type 2 (< 22.0 mm). CONCLUSIONS: Careful attention should be paid to the branches of the uncinate process to the accessory pancreatic duct to enable more accurate diagnoses of the pancreas head region. 相似文献
992.
993.
Keyaki A Nabeshima S Bessho H Uji T Higuchi K Sato T Morimoto M Mori K 《No shinkei geka. Neurological surgery》1999,27(3):275-279
A case of fibrous dysplasia of the frontal bone in a 51 year-old male is described. He was admitted to our hospital with a hard, painless growing mass in the left frontal region. A symmetrical protrusion of his forehead has been observed since several years before. Neurological examination and laboratory data revealed no abnormalities. Skull x-rays demonstrated two different lesions. One showed a ground glass appearance in the supraorbital region, and the other showed a radiolucent lesion with marginal sclerosis crossing the left coronal suture CT scan revealed an intradiploic multilocular mass. T1 and T2 MR images showed an abnormal low-intensity mass, and heterogeneous gadolinium-enhancement was noticed in both lesions. Selective external carotid angiography showed tumor stain in the left coronal mass fed by middle meningeal and superficial temporal arteries mimicking intraosseous meningioma. On the other hand, a supraorbital hyperostotic lesion showed no apparent vascularity. An operation was performed on the left coronal lesion to verify the nature of the progressively enlarging mass, which was histologically confirmed to be a fibrous dysplasia rich in numerous vessels. Postoperative course was uneventful. Correlation with clinical activity and enhancement pattern was not known, however, careful observation is required in hypervascular fibrous dysplasia such as was observed in this case. 相似文献
994.
In vivo intradiscal pressure measurement in healthy individuals and in patients with ongoing back problems 总被引:15,自引:0,他引:15
STUDY DESIGN: In vivo intradiscal pressure measurement in different postures in healthy individuals and in those with ongoing back problems. OBJECTIVES: With the most recent technique, 1) to analyze the influence of degeneration on the intradiscal pressure, 2) to calculate the spinal load on the L4-L5 intervertebral discs, and 3) to assess the relation between the spinal load and movement of the intervertebral motion segment. SUMMARY OF BACKGROUND DATA: Almost all the data on intradiscal pressure are from the studies by Nachemson. The results from these pioneering studies have formed the basis for current knowledge about the in vivo loading conditions of the human spine. Although performed already during the 1960s and 1970s with the technique available at that time, virtually no other similar studies have been performed to corroborate the findings. METHODS: The intradiscal pressure (vertical and horizontal) was measured using an advanced pressure sensor in 8 healthy volunteers and 28 patients with ongoing low back pain, sciatica, or both at L4-L5. Among other calculations, the actual loading conditions in various body positions were calculated in relation to the angle between the two vertebrae of the studied motion segments. RESULTS: The effect of respiration on intradiscal pressure was shown as a continuously periodic fluctuation in the healthy prone individual. The intradiscal pressure was significantly reduced according to the degree of disc degeneration as estimated by magnetic resonance imaging. There possibly was a difference between the vertical and horizontal pressures in the degenerated and nondegenerated discs because the nucleus pulposus was pressure-tropic property. The spinal load increased in the following order of body positions: prone, 144 N; lateral, 240 N; upright standing, 800 N; and upright sitting, 996N (P < 0.0001). In the standing and sitting body positions, the spinal load increased not only with forward bending, but also with backward bending. The spinal load was highly dependent on the angulation in the motion segment. The movements of the spine from a flexed to an extended position made the load of the spine change in a curvilinear fashion, fitting a squared equation in the standing body position. There was a correlation between the spinal load and the angle of the motion segment in the standing but not in the sitting body position. CONCLUSIONS: The spinal load was highly dependent on the angle of the motion segment in normal discs in vivo. The intradiscal pressure in degenerated discs was significantly reduced compared with that of normal discs. However, further studies on the effect of respiratory movement on intradiscal pressure, the difference between vertical and the horizontal pressures, and the difference in the spinal load between standing and the sitting body positions are necessary. The data obtained from the current study are fundamental to understanding the pathomechanisms and biomechanical problems of disc disease. 相似文献
995.
T Okamura R Suzuki Y Nakagawa A Terao S Sato A Kitamura Y Naito H Imano Y Tamura M Iida Y Komachi 《[Nihon kōshū eisei zasshi] Japanese journal of public health》1999,46(8):616-623
Since 1969, community-based stroke prevention programs have been conducted in N town, Kochi prefecture. To clarify factors related to participation in medical checkups including social networks, a cross-sectional questionnaire survey was performed on 6,704 residents aged 40 and over in N town in 1996. 1. Location of the workplace, types of medical insurance and interest in health were significantly associated with participation in medical checkups. 2. Participation in medical examinations provided at the workplace was significantly, inversely related with participation rates in community checkups in the group aged 40 to 59 years. 3. Low independence level in daily activities was inversely associated with participation rates for medical checkups in groups aged 60 years and older. 4. Visiting medical facilities was inversely associated with the participation rate for medical checkups in female groups. 5. The group with the highest social networks score (5 points) had the highest participation rate for medical checkups. After adjusting for other participation related factors, social networks scores had a significantly positive association with the participation rate for medical checkups provided by the Health Services for the Elderly Act. 相似文献
996.
S Araki T Sakai H Sato T Kaneko R Sakai K Yokoyama 《[Nihon kōshū eisei zasshi] Japanese journal of public health》1999,46(9):769-778
Multiple Chemical Sensitivities (MCS) have been defined as an acquired disorder characterized by recurrent symptoms, referable to multiple organ systems, occurring in response to demonstrable exposure to many chemically unrelated compounds at doses far below those established in the general population to cause harmful effects; no single widely accepted test of physiologic function can be shown to correlate with symptoms (Cullen MR, 1987). The etiology of MCS is hypothesized as a toxicant-induced loss of tolerance to multiple chemicals with subsequent manifestation of multiple-organ symptoms triggered by low-level exposure to such chemicals. The involvement of multiple organs might be attributed to a neurogenic switching mechanism. The final diagnosis of MCS is to rely on provocation of symptoms in a exposure chamber by a double-blind method. Relations of MCS to allergy, poisoning, psychogenic illness, chemical sensitivity, idiopathic environmental intolerances etc. are discussed in terms of case definition and etiology of these disorders. 相似文献
997.
H Sato Y Yamada N Ishigure T Nakano H Enomoto S Takahashi Y Kubota J Inaba 《Journal of radiation research》1999,40(2):197-204
Wistar rats inhaled 239PuO2 particles prepared by the calcination of 239Pu hydroxide at 1150 and 400 degrees C. Lung retention, fecal and urinary excretion, and translocation of 239Pu were compared between the two calcination temperatures. The clearance of 239Pu from the lungs was significantly faster in the rats exposed to 239PuO2 calcined at 400 degrees C (low-temperature group) than those exposed to 239PuO2 calcined at 1150 degrees C (high-temperature group). Both the fecal excretion of 239Pu and the ratio of fecal excretion to urinary excretion was greater in the low-temperature group than in high-temperature group. The amounts of 239Pu translocated from the lungs to the other organs were very small. Even in the liver, which accumulated the largest amount of 239Pu except for the lungs, only 0.13-0.20% of the initial lung burden was retained 1 year after inhalation. The amount of 239Pu deposited in the liver was greater in the high-temperature group than in the low-temperature group both at 1 month and 1 year after the inhalation. These findings clearly suggest that the lung retention of 239Pu in rats is significantly affected by the calcination temperature of 239PuO2. 相似文献
998.
PURPOSE: We reviewed the records of 10 patients who had impending central retinal vein occlusion in order judge whether anticoagulant treatment with warfarin potassium (Warfarin) was indicated. PATIENTS: 6 men and 4 women, ranging in age from 25 to 83 (average 55) years were studied. RESULTS: Of 6 eyes, retinal hemorrhage disappeared completely within 6 months. Four patients whose visual acuity was 0.1 or less at one month needed photocoagulation. Four other patients whose late venous circulation time at fluorescein angiography improved within 30 seconds had good visual prognosis, 3 eyes of 4 patients aged 65 or older were not successful in regaining their visual acuity. CONCLUSION: Warfarin was not effective for patients who had clearly lost their visual acuity and the elderly in this series. Late venous circulation time at fluorescein angiography was a useful index for this treatment. 相似文献
999.
Magnetic resonance imaging and tendon anomaly associated with congenital superior oblique palsy 总被引:1,自引:0,他引:1
Sato M 《American journal of ophthalmology》1999,127(4):379-387
PURPOSE: To assess the relationship between tendon anomalies and the volume of the superior oblique muscle in patients with congenital unilateral superior oblique palsy. METHODS: Thirty-three patients with unilateral congenital superior oblique palsy were enrolled. Coronal, cross-sectional magnetic resonance imaging scans of the superior oblique muscle were obtained, and the volume of the paretic superior oblique muscle belly was calculated as a percentage of the superior oblique muscle belly on the normal side. The percentage volume of the affected superior oblique muscle was compared retrospectively with the angle of the vertical deviation in the primary position, the tendon looseness determined by a traction test, and other intraoperative findings. RESULTS: When a tendon was loose, the volume of its muscle belly was significantly smaller than the belly of muscles with a normal taut tendon (Mann-Whitney U test, P = .0005). The average vertical deviation of patients assessed to have loose tendons was 4.80 prism diopters, and the deviation in patients with normal tendons was 9.90 prism diopters. The mean vertical deviation of patients with atrophic muscle belly on magnetic resonance imaging was 18.1 prism diopters, and that with normal muscle structure was 10.1 prism diopters. The cases with loose tendon as determined by the traction test after administration of general anesthesia and the cases with atrophic muscle belly had significantly larger vertical deviation in the primary position than the cases with normal tendons and muscles. (Mann-Whitney U test, P = .01 and .0196, respectively). CONCLUSIONS: The traction test is sensitive enough to detect anomalies of the superior oblique tendons. Anomalous superior oblique tendons are nearly always associated with attenuated superior oblique muscle and this information provides us with an explanation for the phenomenon of laxity of the superior oblique tendon. 相似文献
1000.
The effects of aldose reductase inhibitors on lens protein modifications induced by naphthalene-1,2-dihydrodiol were investigated in vitro to confirm the role of aldose reductase on naphthalene cataract formation. HPLC analysis of naphthalene-1, 2-dihydrodiol incubated with aldose reductase and NAD+indicated the formation of a metabolite peak corresponding to 1,2-naphthoquinone. Soluble proteins from rat lenses prepared by gel filtration of crude lens extracts through Sephadex PD-10, incubated with naphthalene-1, 2-dihydrodiol in the presence of NAD+displayed an absorbance ca 450 nm and their spectra were essentially identical to those of 1, 2-naphthoquinone-protein adducts. Similar spectra were also obtained from proteins isolated from the intact rat lens after in vitro incubation in medium containing naphthalene-1,2-dihydrodiol. The spectra obtained from lens proteins incubated with 1, 2-dihydroxynaphthalene were distinct from those of either naphthalene-1,2-dihydrodiol or 1,2-naphthoquinone. Aldose reductase inhibitors possessing either hydantoin or carboxylic acid groups prevented protein modification induced by naphthalene-1, 2-dihydrodiol but not protein modification induced by 1, 2-dihydroxynaphthalene or 1,2-naphthoquinone. Therefore, the metabolite formed from naphthalene-1,2-dihydrodiol by aldose reductase is 1,2-naphthoquinone. Lens proteins modified by naphthalene-1,2-dihydrodiol appear essentially identical to protein adducts formed with 1,2-naphthoquinone and their formation can be prevented by both hydantoin and carboxylic acid containing aldose reductase inhibitors. 相似文献