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991.
Nonocclusive mesenteric ischemia (NOMI) is a disorder with an extremely high mortality. Salvage of affected patients requires early recognition and aggressive intervention to prevent intestinal gangrene. Dialysis patients represent a group at particularly high risk for this condition. Clinicians should develop a high index of suspicion for NOMI in dialysis patients to lessen the risk of death. A high interventional posture must be maintained due to the notoriously unreliable signs and symptoms of this disorder.  相似文献   
992.
Bertalanffy  H.  Kretzschmar  H.  Gilsbach  J. M.  Ott  D.  Mohadjer  M. 《Acta neurochirurgica》1990,104(3-4):151-155
Summary This case report describes a patient presenting with symptoms of increased intracranial pressure, whose computerized tomographic (CT) scan was highly suggestive of a large low-grade glioma invading the basal ganglia. Magnetic resonance imaging (MRI) revealed a well-demarcated space-occupying mass of increased intensity in the left lateral ventricle and adjacent white matter. Following stereotactic biopsy, which yielded a homogeneous jelly-like material, the mass was removed microsurgically and was found to be most like a colloid cyst on histological examination. Discussion focusses on the clinical and differential diagnostic implications of this very unusual combination of findings.  相似文献   
993.
A review of hip radiographs of patients with severe hemophilia showed Legg-Calvé-Perthes disease in four of 63 patients examined before the era of specific treatment. In another series of 44 patients receiving prophylactic treatment, there was no evidence of Legg-Calvé-Perthes disease. A case report of a boy with severe hemophilia with hip joint bleeding that caused joint capsule distention and greatly increased intracapsular pressure is presented. Based on our findings, and previously published results, we suggest that Legg-Calvé-Perthes disease in hemophilia is caused by increased intracapsular pressure secondary to hemarthrosis.  相似文献   
994.
During a routine physical examination in 1976, a 54-year-old man was noted to suffer from hearing difficulty and continuing tinnitus of his right ear. He had, however, no further consultations for the next five years, although the symptom persisted and gradually worsened. In May 1981, he experienced complete hearing loss in his right ear. A computed tomography disclosed no abnormalities, and other laboratory tests were unremarkable. In September 1981, the patient began to complain of paresthesia of the right angle of the mouth and tongue, right-sided facial paralysis, and walking difficulty. A repeated computed tomography showed a tumor at the right cerebellopontine angle region. A clinical diagnosis of acoustic schwannoma was made. The first operation was performed in December 1981. Complete removal of the tumor was impossible because of its unexpected, unusual hardness. The pathologic diagnosis was a malignant mesenchymal tumor, compatible with a malignant nerve sheath tumor of the acoustic nerve. A second operation was performed in January 1982, but the rapid postoperative regrowth of the tumor necessitated a third operation in March 1982. The patient died in the next month. Family histories did not show any evidence of von Recklinghausen's disease, and neither did the patient have any clinical stigmata of this disease.  相似文献   
995.
To examine the possible role of transscleral outflow routes, enucleated human and porcine eyes underwent noncontact neodymium:yttrium aluminum garnet (Nd:YAG) laser cyclophotocoagulation 3 mm posterior to the limbus. Pars plana lesions were verified histologically. The eyes were perfused with saline solution at 50 mm Hg perfusion pressure, placing the tip of the needle into the hyaloid orbicular space. The outflow facility was 0.072 microliter/min/mm Hg in paired controls and 0.105 microliter/min/mm Hg in human lasered eyes, a difference of 31%. In porcine eyes the difference was 43%. Since concepts of aqueous production, impaired circulation, and inflammation do not apply to enucleated eyes, the increase may be related to pars plana transscleral flow facilitated by disruption of the neuroepithelial barrier.  相似文献   
996.
An 80-year-old man was evaluated for an epibulbar tumor on a phthisical eye. The initial biopsy diagnosis of the epibulbar tumor was poorly differentiated neoplasm. Exenteration of the phthisical eye and orbital contents showed an extensive pleomorphic adenocarcinoma of the nonpigmented epithelium of the ciliary body with extraocular extension. There was evidence of hyaluronic acid secretion and immunohistochemical staining was strong for vimentin, focal for epithelial membrane antigen and S-100 protein, and weak for neuron-specific-enolase. Electron microscopy demonstrated desmosomes between tumor cells, areas of thick, multilaminar basement membrane production surrounding individual tumor cells, and occasional intracytoplasmic intermediate filaments.  相似文献   
997.
The intraocular pressure and the anteroposterior length of the eye are of great clinical importance for the diagnosis and management, before and after surgery, of congenital glaucoma. It is well-known that normal intraocular pressure in children is different from the normal levels in adults. We performed measurements of intraocular pressure and axial length in 141 children who had been admitted for eye problems other than glaucoma. The intraocular pressures were measured with the Perkins hand-held applanation tonometer at the beginning of general anesthesia. Simultaneously, A-scan ultra-sound measurements of the axial lengths of the eyes were made. In 10 children under the age of two years, the intraocular pressure was 11.85 +/- 1.35 mmHg. In 79 children from two to seven years, the intraocular pressure was 12.80 +/- 1.73 mmHg. In 52 children from seven to 15 years, the intraocular pressure was 13.31 +/- 1.79 mmHg. The axial lengths of the eyes in children under the age of two years, from two to seven years, and from seven to 15 years, were 21.31 +/- 0.97 mm, 22.04 +/- 0.92 mm, and 23.22 +/- 1.00 mm, respectively. These results were considered to be guidelines for measuring intraocular pressure and axial length in children suspected of having congenital glaucoma. The differences of intraocular pressures stated by other authors are due to early measurement of the intraocular pressure at the beginning of general anesthesia.  相似文献   
998.
This study has shown that the retinae of Prototherian (egg-laying) mammals possess two neuronal types that are present in non-mammalian retinae, but absent or morphologically different in the retinae of Eutherian (placental) mammals. First, endogenous serotonin-like immunoreactivity has been localized in a population of presumptive amacrine cells in the platypus retina, the first such report in a mammalian retina. Second, the protein kinase C-immunoreactive (PKC-IR) bipolar cells in the echidna retina appear similar to the PKC-IR bipolars in the chicken retina, in that their dendrites give rise to a Landolt's club and their axons are multistratified. By contrast, the PKC-IR rod bipolar cells in the rabbit and in the brushtail possum, a Metatherian (marsupial) mammal, have no Landolt's clubs and their axons form terminal lobes in the innermost stratum of the inner plexiform layer.  相似文献   
999.
The study examines whether the order of administering 2 doses of quinpirole (0.5 and 8 mg/kg) affects the development of behavioral sensitization, as measured by the amount of forward progression and mouthing. Results show that injection of the high dose greatly enhances the subsequent locomotor response to the low dose of quinpirole, but not vice versa. Mouthing activity is not influenced by order of administration but is significantly greater at the higher dose of quinpirole. The present findings are consistent with a hypothesis that locomotor sensitization involves down-regulation of a D1 tone normally inhibitory to D2 locomotor activation.  相似文献   
1000.
The influence of beta-blockers in short- and long-term application on the epithelium of the cornea was studied in rabbits with intact tear film, concentrating not on the completeness of the drug group but on general differences. The new unpreserved beta-blocker timolol was compared on an exemplary level with the following beta-blocker formulas: (1) beta-blocker eye drops with 0.01% of the preservative benzalkonium chloride; (2) beta-blocker eye drops with 0.005% of the preservative benzalkonium chloride, and (3) beta-blocker eye drops with 0.004% of the preservative benzalkonium chloride and the tear substitute polyvinyl alcohol. Exposure time in the short-term test was 30 min, in long-term tests the time was 24 weeks. Any cell damages observed were of only minor importance and rarely of clinical relevance; however, it could be shown that micromorphological cell reactions differed as a function of the preservative concentration. Complete absence of preservatives causes no difference in micromorphologically relevant changes in comparison with the control group. Drugs without preservatives are thus a meaningful alternative for patients with allergies, sensitive eyes or existing impairment of the precorneal film.  相似文献   
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