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71.
An autopsy case of a 19-year-old boy who had shown typical gargoyle features, strictly consistent with mucopolysaccharidosis type II (Hunter's syndrome) was reported. Histologically, cytoplasmic vacuolar change was found In hepatocytes, sinusoidal epithelium of spleen, follicular cells of thyroid, Sertoli cells of testis, chromophobe cell of pituitary and generalized fibroblast-like cells including meninges, cardiac valve and periosteum. The vacuoles consisting of membrane-bound structures with flocculus protein-like material and occasional electron dense bodies on electron microscopy, were considered to be the site of mucopolysaccharide deposition by histochemical analysis. Deposition of lipid material consistent with so-called membranous cytoplasmic body was observed in the neurons of central, peripheral and autonomic nervous system. Hepatosplenomegaly could be explained by cytoplasmic deposition, but the cause of cardiomegaly remained further to be studied. Biochemically hepatic mucopolysaccharide was identified as heparan sulfate, while in the kidney dermatan sulfate and heparan sulfate were detected. The correlation between morphology and biochemistry, and between deposition and degeneration was discussed.  相似文献   
72.
Metastatic tumors in the sellar and parasellar regions are uncommon and rarely detected in clinical practice. We present four cases of sellar and parasellar metastatic tumors, which metastasized from distant organ in one case and extended directly from adjacent structures in three. Common presenting symptoms were cranial neuropathies, headache and facial pain. Invasion into the cavernous sinus was noted in all cases. We report rare cases of sellar and parasellar metastases. Also, we should consider the possibility of metastasis in these regions for patients who showed the above clinical presentations in systemic cancer patients. In extensive diseases, transient symptomatic relief could be obtained by direct surgical management, even in restricted degree.  相似文献   
73.
74.
A rare benign condition of uncertain etiology and pathogenesis, Synovial Chondromatosis (SC) is most often seen intraarticularly in adults but only a handful of cases have been reported extraarticularly in children. Symptoms and physical signs consist of pain, swelling, and osteoarthritic changes related to a mass effect. Here we discuss the case of a 9-year-old boy with documented SC of the knee and critically review the Epidemiology, Clinical Presentation, Gross Anatomy and Microscopic Histopathologic Features as well as the role of Imaging Studies in Diagnosis. In addition, this paper reviews Current Pathogenetic Concepts including the infrequent but distinct possibility of malignant transformation.  相似文献   
75.
Rett syndrome is a severe neurodevelopmental disorder that arises from mutations in the X-linked MECP2 gene. It is almost exclusively seen in girls due to the predominant occurrence of the mutations on the paternal X-chromosome, and also the early postnatal lethal effect of the disease causing mutations in hemizygous boys. We identified a boy with features of classic Rett syndrome who is mosaic for the truncating MECP2 mutation R270X. Chromosome analysis showed normal karyotype. These results indicate that a MECP2 mutation associated with Rett syndrome in females could lead to a similar phenotype in males as a result of somatic mosaicism.  相似文献   
76.
In recent years there have been many studies demonstrating a correlation between increased arterial blood pressure and altered lipid profiles, and there has been an especially positive correlation between high cholesterol levels and blood pressure. There are differences between the various reports that are important. In our study the lipid distribution in 105 hypertensive patients with mild or moderate arterial hypertension according to WHO criteria without clinically or ultrasonographically apparent atherosclerosis was compared to the lipid distribution in 65 age-matched healthy persons. On the epidemiological level a significant, positive association was found between LDL serum levels (P 0.001), Apo B serum levels (P 0.001), serum triglyceride levels (P 0.05) and VLDL serum levels (P 0.01) and arterial hypertension. However, in contrast to recent reports, no significant difference was found between total serum cholesterol levels in normotensives and hypertensives, and there was no difference in HDL serum levels. No evidence could be found for a significant increase in lipoprotein (a) serum levels in hypertensives.Abbreviations LDL low density lipoprotein - VLDL very low density lipoprotein - HDL high density lipoprotein - Apo B 100 apolipoprotein B 100 - Apo A I apolipoprotein A I Correspondence to: H. Vetter  相似文献   
77.
It is generally considered that tuberculosis (TB) is a disease which upregulates Th1 cell function. There is a hypothesis that infection of Mycobacterium tuberculosis may prevent allergic disorders such as bronchial asthma. However, our clinical experience of patients with TB somewhat conflicts this hypothesis. Hence, we investigated Th1/Th2 balance in the peripheral blood of patients with active TB by measuring serum levels of IgE antibody and by intracellular cytokine assay. We found that serum levels of IgE in the patients with active TB were significantly higher than in those with lung cancer or with COPD. In the TB patients, titers of IgE tended to correlate with disease severity. Intracellular cytokine assay demonstrated that IFN-gamma-positive cells were significantly decreased in the patients with active TB compared to normal controls. The ratio of IFN-gamma-positive (Th1-like)/IL-4-positive (Th2-like) cells was remarkably reduced in the TB patients (p < 0.0001). This ratio showed a significant negative correlation with erythrocyte sedimentation rate and with C-reactive protein. Therapy against TB for 2-3 months did not result in significant changes of the Th1/Th2 ratio. These findings suggest that infection of M. tuberculosis does not systematically upregulate Th1 cells in some patients, and is unlikely to prevent allergic disorders like asthma.  相似文献   
78.
Platelet-vessel wall interaction is an important process in physiological hemostasis and pathological thrombosis. In oriental countries, some medicinal plants have been claimed for uses to improve circulation, induce fibrinolysis or prevent thrombosis. In cooperation with chemists using bioassay-based step-by-step purification, some antiplatelet agents were isolated from plant sources. According to their effects on platelet aggregation, release reaction and signal transductions involved, these antiplatelet agents can be classified into eight groups: 1. platelet-activating factor (PAF) antagonists, 2. collagen-receptor antagonists, 3. thromboxane-receptor antagonists, 4. ADP-receptor agonists, 5. inhibitors of phosphoinositide breakdown, 6. inhibitors of thromboxane formation, 7. agents increasing cyclic nucleotides, and 8. protein kinase C activators. These new pharmacological agents derived from medicinal plant sources may be useful as leads to develop as effective cardiovascular drugs.  相似文献   
79.
General anesthetics modulate autonomic nervous system function including thermoregulatory control, which resides in the preoptic area of the anterior hypothalamus. However, the mechanism by which anesthetics modulate hypothalamic function remains unknown. We hypothesized that isoflurane increases norepinephrine release in the preoptic area and in the posterior hypothalamus causing hypothermia during anesthesia. To test this hypothesis, we performed a series of in vivo and in vitro studies in rats. In vivo studies: 1) Norepinephrine release was measured by microdialysis in the preoptic area or the posterior hypothalamus (n=9 each) before, during (30 min), and after (50 min) rats were anesthetized with 2% isoflurane. 2) In five rats, blood gases and arterial pressure were measured. 3) Body temperature changes (n=6 each) were measured after prazosin (0, 0.05, 0.5 microg), norepinephrine (0, 0.1, 1.0 microg), or 0.5 microg prazosin with 1.0 microg norepinephrine injection into the preoptic area. In vitro study: Norepinephrine release was measured from anterior or posterior hypothalamic slices (n=10 each) incubated with 0, 1, 2, or 4% isoflurane in Ca2+-containing buffer or with 4% isoflurane (n=10) in Ca2+-free buffer. Data were analyzed with repeated measures or factorial ANOVA and Student-Newman-Keuls tests. P<0.05 was significant. During anesthesia, norepinephrine release in the preoptic area was increased approximately 270%, whereas the release in the posterior hypothalamus remained unchanged. During emergence, posterior hypothalamic norepinephrine release increased by approximately 250% (P<0.05). Rectal temperature changes correlated with norepinephrine release from the preoptic area. Norepinephrine in the preoptic area enhanced isoflurane-induced hypothermia, while prazosin reversed it. Norepinephrine release from anterior hypothalamic slices increased at all isoflurane concentrations, but only at the highest concentration in posterior hypothalamic slices. Under Ca2+-free conditions, 4% isoflurane increased norepinephrine from both regions. These results suggest that augmentation of norepinephrine release in the preoptic area is responsible for hypothermia during general anesthesia.  相似文献   
80.
Intracranial pressure (ICP) monitoring is a critical measure for avoiding severe brain dysfunction or brain death by directing supportive therapy so as to prevent ICP increase severe enough to reduce cerebral blood perfusion. Such situations occur with brain swelling, increased cerebral vascular volume, and increase in cerebrospinal fluid (CSF) volume. Causes include ischemic stroke, subarachnoid bleeding, brain contusion, encephalitis (as in Reye's syndrome), and hydrocephalus from meningitis or neoplasm. When several days of ICP monitoring can direct resolution of the pressure crisis, the invasive direct connection of an intracranial sensor with external recording device carries only minimal infection risk. Prolonged ICP monitoring for weeks or months demands telemetry and becomes desirable in a number of chronic disease problems including both congenital and acquired hydrocephalus where enlarged and pressurized cerebral ventricles develop with reduced absorption of continuously secreted CSF. Although the primary disturbance in CSF circulation can remain incurable, its palliation by valve-regulated CSF diversions or shunting can restore normal brain function and in infants permit normal brain development. Missing this goal can result from failure to maintain a sufficiently normal pattern of CSF dynamics and ICP. Monitoring of the CSF pressure fluctuations transmitted through an intraventricular catheter provides the most accurate record of ICP pulsations. Therefore, a pressure sensing module can be “T'd” into an existing shunt system in continuity with the already placed ventricular tube. The capacity to monitor ICP accurately by telemetry was first established in dogs made hydrocephalic to assure free CSF pulse through a ventricular catheter (1,2,3, 4,5). The subsequent use of ICP monitoring by telemetry in three patients will be described.  相似文献   
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