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901.
902.
beta 2-Microglobulin (beta 2-MG)-related amyloidosis has been reported as a complication in long-term hemodialysis patients. We observed beta 2-MG amyloid deposits in synovial sheaths, bone cysts and gastric mucosa. They showed unique ultrastructural features, that is bundles or nodules consisting of curved or linear amyloid fibrils, associated with various cell reactions. The electron-microscopic histochemical study showed that they strongly stained with periodic acid-silver methenamine stain. A similar phenomenon was noticed in the spicules or bundles of amyloid fibrils in primary and secondary renal amyloidosis. With the cationic reagent toluidine blue 0, proteoglycan-like structures were observed around amyloid bundles and nodules, but not on each fibrils. Based on these results, we postulate that there is a close relationship between ultrastructural features and histochemical characteristics in beta 2-MG amyloid fibrils.  相似文献   
903.
This is the second reported case of a malignant fibrous histiocytoma of the heart that metastasized to the brain. A 33-year-old woman developed headache, nausea, and ataxic gait 9 months after removal of the tumor from the left atrium of the heart. Computed tomographic and magnetic resonance imaging scans disclosed multiple metastatic tumors in the brain. Although dramatic improvement in her symptoms and signs followed the removal of the brain tumors, she died of tumor recurrence in the left atrium 3 months after the removal of the metastatic brain tumors.  相似文献   
904.
This is a case report on a patient with double cancer of kidney and urinary bladder. The patient was a 65-year-old female, and she was admitted with the chief complaint of gross hematuria and right flank pain. After careful examinations, she was diagnosed with right nonfunctioning kidney caused by invasive bladder cancer. Computerized tomography incidentally revealed a mass in the upper pole of the left kidney. Selective left renal arteriography showed stretched arteries and irregularity and tortuosity of the smaller vessels. She was diagnosed with double cancer of bladder and left kidney. Owing to the damage of the right renal function, left partial nephrectomy, total cystectomy, right nephroureterectomy and left ureterocutaneostomy were performed. According to DMSA scintigraphy measured 15 days later, the uptake value of the left kidney was 13.25%, compared to the preoperative value of 25.62%. To date, this case is 36th reported case in Japan.  相似文献   
905.
The occurrence sites of intracranial primary germ cell tumors are most often the pineal and suprasellar regions. The histological type observed most frequently in these tumors is germinoma. Cases of embryonal carcinoma arising in the basal ganglia are rarely reported. To our knowledge, only 4 such cases have been previously reported in the literature. A case of an embryonal carcinoma arising in the basal ganglia is reported. A 17-year-old boy was admitted to our hospital on July 30, 1988 because of headache and vomiting, and a right hemiparesis. On admission, physical inspection showed no abnormalities and neurological examination revealed obtunded consciousness, a right central facial paresis and a right hemiparesis with Hoffman and Babinski reflexes. Noncontrast CT scan showed a large mass of low-to slightly high-density in the region of the left basal ganglia accompanied with midline shift and ventricular dilatation. Enhancement of the lesion was made by contrast CT scan. It was not homogeneous. Cerebral angiogram displayed a contralateral shift and an unrolling of the anterior cerebral artery, a lateral stretch of middle cerebral artery, a downward stretch of anterior choroidal artery and a tumor stain fed by the Heubner artery. On August 3, left frontotemporal craniotomy was performed. The tumor was totally removed in a piecemeal manner using microsurgical techniques. Histopathological diagnosis was mixed-type of germ cell tumor comprising embryonal carcinoma and teratoma. Postoperative CT scan showed complete disappearance of the tumor. A course of radiation of 4950 rads and two courses of a combination chemotherapy with cis-platinum, vinblastine and bleomycin were given within 3 months after the operation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
906.
Experimental study on chronic entrapment neuropathy   总被引:1,自引:0,他引:1  
This study was undertaken to clarify the pathology and pathophysiology of chronic entrapment neuropathy. Ten mm long Silastic tubes with internal diameter of 1.5 mm were placed on the right sciatic nerves of adult Wistar rats. Morphological and functional changes were studied from one to 14 months after tubing. The earliest changes consisted of thickening of the epineurium and perineurium, followed by breakage of nerve-blood barrier. Intraneural edema and segmental demyelination were evident at the central and peripheral areas of funiculi from 4 months after tubing. At 14 months after treatment, intraneural fibrosis was recognized. Compound action potentials and motor nerve conduction velocity were decreased in 4 and 8 month specimens respectively. Tadpole deformity of the myelin sheath was observed at 4 months and later. The fast axonal transport declined at 8 months after tubing. Our results were compatible with clinical and pathological findings of human materials. This model was thought to be useful one to elicit the pathology and pathophysiology of clinical entrapment neuropathy.  相似文献   
907.
We have developed an implant heating system (IHS) for interstitial hyperthermia of brain tumors. IHS consists of three compartments: ferromagnetic implant with low Curie point, induction coil and generator to produce high frequency magnetic field. The device works as follows: It is heated up to a Curie temperature (Tc) by Eddy current under the magnetic field. Heat generated in the implant is conducted to the tumor tissue into which it has been implanted. To evaluate the effect of this hyperthermia, a brain tumor model was produced by innoculation of VX2 tumor cells and treated either by hyperthermia with IHS alone, chemotherapy with ACNU alone, or with a combination of both. The longest survival was obtained by the combined treatment, and significant prolongation of survival was found in the single treatment groups. In the Phase I clinical trial, one or several implants (1.8 mm X 15 mm, Tc = 68 degrees C) made of Fe-Pt alloy were placed in the tumor by CT guided stereotactic procedure, or manually during craniotomy. Hyperthermia of above 42 degrees C for 30 to 60 minutes twice a week was brought about in ten cases of malignant brain tumor. CT evaluation was made in nine cases treated for more than ten times in this way. Five out of the nine cases responded to this hyperthermia with irradiation. In conclusion, a safe, repeated and longterm treatment was possible without significant side effects. The hyperthermia with IHS may also be applicable to benign intracranial tumors and neoplasms in other part of body as well.  相似文献   
908.
Aneurysms of the inferior left ventricular wall represent only a small fraction of all aneurysms that have been reported in surgical series. And in comparison to anterior left ventricular aneurysms, a comparatively higher percentage of reported inferior wall aneurysms was classified as false. A 73-year-old male was admitted for acute inferior myocardial infarction. Three weeks after admission, cardiac catheterization was carried out. Coronary arteriography revealed triple vessel disease and left ventriculography showed an aneurysm of the inferior left ventricular wall, whose feature near the mitral annulus was multiple fenestrations. Left ventricular aneurysmectomy and aortocoronary bypass grafting to the left anterior descending artery were simultaneously performed under cardiopulmonary bypass with moderate hypothermia. The pathological feature was a true aneurysm. The postoperative course was uneventful.  相似文献   
909.
Implantation of scleral-fixated posterior chamber intraocular lenses   总被引:1,自引:0,他引:1  
A surgical technique for implanting a posterior chamber intraocular lens (IOL) in eyes without capsular or zonular support is presented. A 10-0 polypropylene suture attached to a standard needle is tied to the apex of each haptic and passed transclerally through the ciliary sulcus to secure the haptics at the 3 o'clock and 9 o'clock meridians. This technique produced good visual results in six aphakic patients who were contact lens intolerant, two patients in whom capsular or zonular rupture at the time of cataract surgery precluded standard nonsuture fixation techniques, one patient who had intracapsular cataract extraction for a subluxated, cataractous lens, and one patient who had secondary IOL implantation in combination with penetrating keratoplasty for aphakic bullous keratopathy. Advantages over other techniques of posterior chamber lens implantation in the absence of capsular support include technical ease, avoidance of iris fixation, and more precise placement of scleral fixation sutures, thus minimizing IOL decentration.  相似文献   
910.
We investigated the effects of energy restriction on the pituitary-ovarian axis and on a hormone responsive gene, the mouse mammary tumor virus (MMTV). Female C3H/SHN F1-hybrid mice, known to display a high incidence of mammary tumors, ate an energy-restricted diet (48 kcal/wk) or a control diet (95 kcal/wk) beginning at the time of weaning. By 67 wk of age, 12 of 32 mice in the control group, but none of the 33 mice in the energy-restricted group, had developed mammary tumors. Six tumor-free mice from each group were studied in detail at 67 wk of age. All six tumor-free control mice, but none of the six energy-restricted mice, showed uterine endometrial hyperplasia at autopsy. Mice subjected to energy restriction did not display an estrous cycle. The average levels of MMTV mRNA in mammary glands and uteri were strongly reduced by energy restriction. MMTV mRNA levels in mammary glands from control mice were two orders of magnitude lower than those in mammary tumors. Energy restriction lowered the percentage of pituitary mammatropes and suppressed proliferation of mammatropes with advancing age. Energy restriction thus appeared to inhibit endometrial hyperplasia and to decrease MMTV production at the mRNA level in the mammary glands and in the uterus. These effects may be a consequence of hormonal changes originating at the pituitary-ovarian axis.  相似文献   
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