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Aneurysm of persistent primitive hypoglossal artery   总被引:2,自引:0,他引:2  
A patient with a ruptured intracranial aneurysm of the right persistent primitive hypoglossal artery is described. Clipping of the aneurysmal neck was achieved by a far lateral approach together with drilling of the jugular tubercle, and it was concluded that this approach should be followed for safe and complete clipping.  相似文献   
104.
OBJECTIVE: To investigate the effect of sodium, protein and calcium in habitual diets on bone resorption. DESIGN: A cross-sectional study. SETTING: A community-based study. SUBJECTS: Healthy free-living male (n=342) and female (n=421) volunteers aged 20-79 y recruited for a health and nutrition examination survey conducted by a local government. METHODS: Bone resorption was assessed by the measurement of free deoxypyridinoline in 24 h urine. Dietary assessment was by one-day dietary record method. Sodium and urea in 24 h urine were also measured for assessment of sodium and protein intake. The relationships between deoxypyridinoline excretion and the dietary factors were examined using correlation and multiple regression statistics. RESULTS: In women aged 50-79 y, protein intake was positively associated with deoxypyridinoline excretion (P<0.05); and the urinary deoxypyridinoline/creatinine ratio was positively associated with both the urinary calcium/creatinine ratio (P<0.01) and sodium/creatinine ratio (P<0.05). In the multiple regression model, the association of the deoxypyridinoline/creatinine ratio and sodium/creatinine ratio was still significant (P<0.05) after adjustment for possible confounders, in this sex and age group. CONCLUSION: In elderly women, habitual excess sodium in diets may result in bone loss through accelerated bone resorption.  相似文献   
105.
The process of the development of the intracranial vessels was studied by means of immunohistochemical analysis of factor VIII in normal and exencephalic chick fetuses. The results revealed that the development of blood vessels in exencephalic brain was far advanced beyond the norm, with intense immunoreactivity to factor VIII on postincubation day 16 exceeding that on day 21 in normal controls. Compared with results regarding the direction of the overgrowth in the neuronal maturation process in the previous study using the chick exencephaly model, the findings of overmatured blood vessels were compatible with NSE- and somatostatin-positive elements that appeared especially in the overgrowth foci. The results of the present study suggested the pathogenic development of the area cerebrovasculosa in the neural placode as a phenomenon consequent upon hypervascularization in response to neuronal overgrowth, as seen in human cases of exencephaly or anencephaly. We emphasize the significance of this specific phenomenon in the development of the fetal central nervous system, namely neurovascular developmental interaction.  相似文献   
106.
Methylterahydrophthalic anhydride (MTHPA) is used as a hardening agent in an epoxy resin system. Because work-related nasal symptoms were observed in some workers exposed toMTHPA at two condenser plants, a cross-sectional survey was performed to improve their work environment. MeanMTHPA levels in the manufacturing processes to which the workers were routinely assigned were extremely low (1.09-22.4 μg/m3). However, specific IgE antibody (S-IgE) was detected in 9 (32%) of 28 workers. Of these, 8 (89%) had nasal symptoms. An IgE-mediated mechanism seems to be associated with at least some of the cases of work-related nasal symptoms. This indicates that the occupational health administration ofMTHPA cannot be controlled simply by limiting exposure in the work environment. Total IgE (T-IgE) levels were significantly higher in S-IgE-positive workers than in S-IgE-negative workers (geometric mean, 200.5 and 51.3 IU/ml, respectively; p<0.002, unpaired t test). These findings demonstrate that workers in whom S-IgE is less likely to be produced, i.e., those in whom the T-IgE level is 80 IU/ml or less, should be assigned to work in these manufacturing processes.  相似文献   
107.
108.
Reduced vasodilatory capacity resulting from occlusive lesions of the major cerebral arteries may return to normal without surgical revascularisation. We aimed to determine prospectively the frequency and predictors of recovery of impaired haemodynamics as demonstrated by acetazolamide (ACZ) reactivity on single-photon emission computed tomography (SPECT). Vasoreactivity was measured by 123I-IMP SPECT with an ACZ challenge, in 37 medically treated patients with unilateral occlusive disease of the internal carotid or middle cerebral artery at an interval of 1–2 years. Each ACZ challenge test was analysed semiquantitatively by calculating the degree of increase in cerebral blood flow (CBF) asymmetry after ACZ administration (ΔAI). Vasodilatory capacity was abnormal initially in 20 patients (65 %); eight of whom (40 %) exhibited spontaneous normalisation on follow-up. Although the baseline characteristics did not differ significantly between patients with or without increase in reactivity, logistic regression analysis revealed that the initial ΔAI (P < 0.05) and the type of vascular lesion (stenosis or occlusion) (P < 0.05) correlated significantly with a return towards normal of reduced ACZ reactivity. Spontaneous improvement of impaired vasodilatory capacity may not be a rare phenomenon. We found that mild reduction in the initial ACZ reactivity and a stenosis, but not complete occlusion, were independent factors contributing to normalisation of impaired cerebral haemodynamics. Received: 12 October 1998/Accepted: 27 April 1999  相似文献   
109.
Allelotype and replication error phenotype of small cell lung carcinoma   总被引:3,自引:1,他引:3  
Allelotype and replication error (RER) phenotype analyses were performed to clarify the pathogenetic significance of inactivation of tumor suppressor genes and genomic instability in the genesis and progression of small cell lung carcinoma (SCLC). We examined 37 cases of SCLC for loss of heterozygosity (LOH) and microsatellite instability at 49 loci on all 39 nonacrocentric chromosomal arms. LOH was frequently (>70%) detected on chromosomes 3p (29/32, 90.6%), 5q (15/21, 71.4%), 13q (25/26, 96.2%), 17p (22/25, 88.0%), and 22q (24/33, 72.7%). Frequent LOH (>70%) on these loci was observed even among seven cases of stage I tumors. The incidence of LOH on all 39 nonacrocentric chromosomal arms was not significantly different between primary tumors and metastases. These results suggest that inactivation of multiple tumor suppressor genes accumulates relatively early during progression of SCLC and it may be responsible for clinically and biologically aggressive phenotype of SCLC. RER was observed in 6/37 (16.2%) of SCLC, however, RER at multiple loci was observed only in two cases. Therefore, it was indicated that genomic instability is uncommon, but might play a role in the genesis of a small subset of SCLC.   相似文献   
110.
CD44 is a cell surface glycoprotein with a number of isoforms generated by alternative splicing of ten 'variant' exons in humans. Variant exon 6-containing isoforms of CD44 (CD44v6) have been implicated in the metastatic potential of rat carcinoma cell lines. Human homologues of CD44v6 are expressed in several tumour types and are involved in their progression. In the present study, we examined the expression of CD44 mRNA in 20 acute myelocytic leukemias by semiquantitative RT-PCR analysis and assessed its prognostic value. In all leukemic cells the predominant isoform was the 'standard' form of CD44 (CD44H), and intense bands were found in eight cases. CD44v6 was expressed in 11 cases, although its levels and those of other variants containing exon v7 through to v10 were much lower than those of CD44H. Isoforms containing exon v4 or v5 could not be detected. The expression of CD44v6 correlated with the death rate from leukemia (p > 0.05), but was not related to other risk factors. On the other hand, the intense expression of CD44H did not correlate with the prognosis of leukemia. CD44v6 thus appears to be a marker for the poor prognosis of acute myelocytic leukemia.  相似文献   
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