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61.
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   
62.
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   
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64.
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   
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The risk of cerebral infarction (CI) in an individual is dependent on the interplay between genetic risk factors and environmental influences. Binding of thromboxane A2 (TXA2) to its receptor (TP) modulates thrombosis/hemostasis and plays a significant role in the pathogenesis of CI. The aim of the present study was to investigate the relationship between human TP gene single nucleotide polymorphisms (SNPs) and haplotypes and CI in a Japanese population. A genetic association study was performed in 194 CI patients and 365 non-CI subjects by specifically characterizing 6 SNPs in the human TP gene (rs2271875, rs768963, rs2238634, rs11085026, rs4523 and rs4806942). Analysis demonstrated that there were significant differences in the overall distribution of genotypes and dominant or recessive models of rs2271875 and rs768963 between the CI and the non-CI groups. Multiple logistic regression analysis revealed that the C allele of rs768963 was significantly associated with CI (p = 0.029), even after adjusting for confounding factors (odds ratio: 2.41). Further, the C-T-C haplotype of rs768963-rs2238634-rs4806942 was significantly more frequent in the CI group (23.0%) than in the non-CI group (17.7%). These results suggest that specific SNPs and haplotypes may have utility as genetic markers for the risk of CI and that TP or a neighboring gene is associated with the increased susceptibility to CI.  相似文献   
67.
Progressive multifocal leukoencephalopathy (PML) is caused by opportunistic infection of JC virus which belongs to Papovavirus, and presents with progressive demyelinating lesion in the central nervous system. PML was originally reported as a rare complication of hematologic disorders, but later greatly increased in number in association with acquired immunodeficeincy syndrome (AIDS). Original neuropathological features of PML consist of demyelination lacking inflammatory reaction or necrosis, accompanying oligodendroglial nuclear inclusions in the periphery of demyelination. The lesion is preferentially localized to gray-white junction of the cerebral hemisphere and manifests as characteristic demyelinating lesion, called scallopping. Detection of JC virus is essential for the final diagnosis of PML and is achieved via immunohistochemical detection of JC virus with antibodies raised against their components, ultrastructural demonstration of virions characteristic of JC virus, or detection with in-situ hybridization of the genome of JC virus. JC virus can replicate only in oligodendroglial cells, but astrocytes are frequently infected by the virus. The resume of immunological function through therapeutic intervention develops new pathology in PML, exhibiting severe inflammatory reaction with edema and necrosis. This new pathological feature is called immune reconstruction syndrome and clinically presents with severe progression in symptoms of the central nervous system. Nevertheless, treatment of PML is directed for the elimination of the viruses by host immune system. The modification of the above immune reconstruction syndrome is essential for successful outcome of such therapeutic trial.  相似文献   
68.
A case of thrombasthenia (Glanzmann) associated with an intracerebral cavernous angioma in a 32-year-old woman is reported. Since her childhood, the patient had experienced a tendency to develop purpura following minor trauma. But she had not had major bleeding even during pregnancy and delivery. On April 4, 1987, she presented generalized convulsion. A high density mass in the right temporal lobe was demonstrated with CT scan. Carotid angiogram was normal except that the right anterior choroidal artery was stretched. Inhomogeneous signal intensities in T1- and T2-weighted MRI images were seen in the tumor locus. The clinical diagnosis was cavernous angioma which was complicated with intracerebral hemorrhage. The patient had a disorder of platelet function without thrombocytopenia. Her bleeding time was markedly prolonged. Because of this, we did not try surgical excision at first. During the 13-month observation period, however, intracerebral bleeding occurred 5 times. We decided to operate on the patient using fresh blood and platelet transfusion. The postoperative course was uneventful and pathological diagnosis confirmed cavernous angioma. We would like to emphasize possible pitfalls in treating cases of intracerebral angioma with thrombasthenia.  相似文献   
69.
The thymoma-prone rat of the BUF/Mna strain is a useful model for human thymoma. In this strain thymoma development is regulated by a single autosomal susceptible gene, Tsr-1. At pre-thymoma age, BUF/Mna rats have extremely large thyrauses, when compared to those of other strains of rats. Genetic studies in crosses between BUF/Mna rats with large thymuses and WKY/NCrj rats with small thymuses suggested the presence of a major autosomal gene, Ten-1 , which contributes to thymus enlargement in a backcross population. Linkage studies between Ten-1 and microsatellite markers in backcross rats of (WKY/NCrj×BUF/Mna)Fl×BUF/Mna have led to the localization of Ten-1 in chromosome 1. This result may provide an approach to clone Tsr-1 , which could be allelic to Ten-1.  相似文献   
70.
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