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81.
Single photon emission computerized tomography (SPECT) is now widely used as one of the tools in evaluating cerebral blood flow (CBF). The authors report the CBF changes in childhood hydrocephalus. Five pediatric cases studied by 123I-IM SPECT in children are presented. The authors counted radioactivities both in early and delayed images in each patient, and calculated the reabsorption ratio (RR). Two negative-RR cases and three positive-RR cases were found. All of the negative-RR patients had a poor prognosis, while all of the positive-RR patients had a favorable outcome.  相似文献   
82.
BACKGROUND: Maternal viral infection is associated with increased risk for schizophrenia. It is hypothesized that the maternal immune response to viruses may influence fetal brain development and lead to schizophrenia. METHODS: To mimic a viral infection, the synthetic double strand RNA polyriboinosinic-polyribocytidilic acid (poly I:C) was administered into pregnant mice. Behavioral evaluations (thigmotaxis, methamphetamine [MAP]-induced hyperactivity, novel-object recognition test [NORT]), sensorimotor gating (prepulse inhibition [PPI]), and biochemical evaluation of the dopaminergic function of the offspring of phosphate-buffered saline (PBS)-treated dams (PBS-mice) and that of poly I:C-treated dams (poly I:C-mice) were examined. RESULTS: In juveniles, no difference was found between the poly I:C-mice and PBS-mice. However, in adults, the poly I:C-mice exhibited attenuated thigmotaxis, greater response in MAP-induced (2 mg/kg) hyperlocomotion, deficits in PPI, and cognitive impairment in NORT compared with the PBS-mice. Cognitive impairment in the adult poly I:C-mice could be improved by subchronic administration of clozapine (5.0 mg/kg) but not haloperidol (.1 mg/kg). Increased dopamine (DA) turnover and decreased receptor binding of D2-like receptors, but not D1-like receptors, in the striatum were found in adult poly I:C-mice. CONCLUSIONS: Prenatal poly I:C administration causes maturation-dependent increased subcortical DA function and cognitive impairment in the offspring, indicating a neurodevelopmental animal model of schizophrenia.  相似文献   
83.
84.
We reevaluated the optimum conditions for analysis of 13 urinary organic acids using solvent extraction and GC/MS by the stable isotope dilution technique. The acids analyzed were uracil, and lactic, oxalic, 3-hydroxybutyric, succinic, fumaric, glutaric, adipic, pyroglutamic, 2-ketoglutaric, orotic, sebacic, and citric acids. Analytical recovery and accuracy for 13 organic acids ranged from 90 to 107% and from 1.6 to 13.7%, respectively. The optimal pH for most organic acids was 1-2, while that for oxalic and citric acids was 0.25, and that for 2-ketoglutaric and orotic acids was 0.5. The presence of urinary albumin decreased the extraction rates of organic acids, especially of orotic and citric acids; in slight albuminuria (0.5 g/l) the extraction recovery (the extraction rate with albumin/that without albumin) of orotic and citric acid was 38% and 67%, respectively, and in more marked albuminuria (5 g/l), 6% and 26%. Membrane pretreatment with Centricon-3 improved these extraction rates under the condition of albuminuria. Dehydration with the desiccant agent decreased urinary acid extraction rates, especially of uracil and orotic and citric acids. The extraction rates of these three organic acids was decreased in albuminuria and by the desiccant agent. Accurate quantitative analysis of urinary organic acids by the stable isotope dilution technique is necessary for routine examination conducted in clinical laboratories.  相似文献   
85.
Analogues of erythrocyte protein 4.1, spectrin and ankyrin were examined in the thyroid gland of pig and rat by immunohistochemical techniques. Analysis with immunofluorescence microscopy revealed that the peripheral cytoplasm and apical-lateral plasma membrane of follicle epithelial cells of thyroid glands were stained with antibodies against erythrocyte protein 4.1, spectrin, or ankyrin. The results indicate that membrane skeletal protein lattice might exist in thyroid follicle epithelial cells.  相似文献   
86.
A case of traumatic spinal subarachnoid hematoma causing compression of the cauda equina is reported here. The patient, a 76 year-old woman, who had fallen down by accident 1 month before, was admitted to our hospital presenting lumbar pain radiating into her right thigh, monoplegia of the right leg and urinary incontinence. Myelography and metrizamide CT demonstrated a filling defect mimicking intradural extramedullary tumor at the level of L1 and L2. Magnetic resonance imagings (MRI) revealed a subacute or chronic hematoma compressing the conus medullaris and the cauda equina. Operation was performed and an old hematoma, which occupied most of the spinal subarachnoid space and compressed the conus and cauda equina from right to left, was removed. No definite bleeding point was detected and no traumatic change was seen on the cord. Neither tumor nor abnormal vessel was detected. After surgery, the symptoms improved partially. On a review of the literature, we found only 4 cases of traumatic spinal subarachnoid hematoma, all of which occupied the cervical or thoracic portion of the spine. Our case is the first report, except for the cases following lumbar spinal tap, of traumatic spinal subarachnoid hematoma causing compression of the cauda equina. Though usually blood in CSF diffuses immediately, a clot may be formed when a large amount of bleeding obstructs the spinal canal. In our case, furthermore, deformity and narrowing of the spinal canal had preceded for many years, following lumbar vertebral compressed fracture related with osteoporosis. This might have promoted the process of canal obstruction and clot formation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
87.
This study examined the acid base disturbances in 18 adults with acute renal failure (ARF) from one of new aspects, which is lactate metabolism and pathophysiology. 10 patients (55%) of them were accompanied by lactic acidosis and 9 patients (90%) of those with lactic acidosis also had severe hepatic failure. Mortality of patients with lactic acidosis was 80%, and much higher than that of ARF (66.7%). Lactate, pyruvate, lactate-to-pyruvate ratio (L/P) were 76.7 +/- 15.66 mg/dl, 3.30 +/- 0.74 mg/dl and 19.9 +/- 1.41, respectively. All of them significantly raised, compared to values of healthy adults, patients with liver cirrhosis, chronic renal failure and diabetes mellitus. Arterial pH and HCO3- levels were 7.20 +/- 0.04 and 10.6 +/- 1.20 mEq/l. Anion gap (AG) was 30.0 +/- 3.66 mEq/l. Significant correlations of lactate with pH, HCO3-, AG and L/P were demonstrated, while correlations of lactate with BUN, CR and prothrombin time were not significantly observed. Lactic acidosis results from two mechanisms. One is lactate overproduction (e.g tissue hypoxia) and the other is lactate underutilization (e.g severe liver and/or renal failure). Whenever lactic acidosis occurred, both mechanisms were present simultaneously and continuously. Especially, the latter mechanism had a very important role on it, and seemed to decide the prognosis of the patients with lactic acidosis. Therapy of lactic acidosis was very difficult. First of all, we tried to improve the circulatory failure and severe acidemia (pH less than 7.20) not to fall into vicious cycle. Then, CAVH, if combined with alkali infusion, seemed to be the most useful technique in managing lactic acidosis with ARF.  相似文献   
88.
Seven human gastric cancer xenografts with different concentrations of EGF receptor were established in nude mice. The expression of EGF receptor in the tumors was demonstrated by Western blotting with anti-EGF receptor antibody, binding assay with 125I-EGF and immunohistochemistry with anti-EGF receptor antibody. Western blotting revealed EGF receptor doublet bands at molecular masses of 150 KDa and 170 KDa in all of the samples. The concentration of 125I-EGF binding activity in the tumors ranged from 36.0 to 11,000 fmol/mg protein, with a mean of 345 fmol/mg protein. EGF receptor was also demonstrated immunohistochemically on the apical border of the glands and the cell membrane of the tumor cells. There seemed to be a close correlation between the concentration of 125I-EGF binding activity and the doubling time of these tumors in nude mice (gamma = -0.68). However, no definite correlation was observed between EGF ligand binding and histological features of intestinal type or diffuse type. The expression of EGF receptor appears to facilitate the growth of human gastric cancer xenografts in nude mice.  相似文献   
89.
BACKGROUND: A recent report provided evidence that a disintegrin and metalloprotease domain 33 (ADAM33), a member of the ADAM family, is a novel susceptibility gene in asthma linked to bronchial hyper-responsiveness. However, there has been no investigation of the genetic role of ADAM33 variants in nasal allergy. OBJECTIVE: The purpose of this study was to test the association between ADAM33 polymorphisms and Japanese cedar pollinosis (JCPsis), a most common seasonal allergic rhinitis in Japan. METHODS: We conducted a case-control association study among a Japanese population, involving 95 adult individuals with JCPsis and 95 normal healthy controls. A total of 22 single-nucleotide polymorphisms (SNPs) in ADAM33 were genotyped using PCR-based molecular methods. RESULTS: Six SNPs of ADAM33 gene, three in introns (7575G/A, 9073G/A and 12540C/T) and three in the coding region (10918G/C, 12433T/C and 12462C/T), were strongly associated with JCPsis (P = 0.0002-0.022 for absolute allele frequencies) and most of the SNPs were in linkage disequilibrium with each other. A higher frequency of the common alleles of these SNPs was noted for the subjects with JCPsis in comparison with healthy controls. We also identified a haplotype associated with the disease susceptibility. In addition, associations were found between ADAM33 polymorphisms and various cedar pollinosis phenotypes including clinical severity, eosinophil counts in nasal secretion and allergen-specific IgE levels in sera, but not total serum IgE levels. CONCLUSION: These results indicate that polymorphisms in the ADAM33 gene are associated with susceptibility to allergic rhinitis due to Japanese cedar pollen, but the functional relationship still needs clarification.  相似文献   
90.
Objects We evaluated whether the presence of lacunar skull deformity (LSD) with myelomeningocele is a predictive factor for subsequent hydrocephalus development. Materials and methods We reviewed the clinical and radiological records of 18 infants with myelomeningocele, divided the patients into groups with (group A, n=9) and without (group B, n=9) ventriculomegaly at birth and assessed whether the presence of LSD was predictive of the necessity for ventriculoperitoneal shunt (VPS) placement. Results LSD was present in five group A patients. All nine group A patients underwent VPS placement. Among the group B patients, five had LSD; they underwent VPS placement. A significantly higher proportion of those with ventricle enlargement or LSD at birth required VPS placement (p=0.0001). Conclusion Adding to the ventriculomegaly at birth, the presence of LSD alerts to the necessity to monitor these infants closely to determine the necessity for VPS placement.  相似文献   
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