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81.
The absolute structure of a new antibiotic lactonamycin is described. The NMR studies deduced one of four possible structures for the aglycon attached by a rhodinose through glycosidic bond. The stereochemistry of the sugar obtained by an acid hydrolysis was determined to be L-form by measuring optical rotation. The stereochemistry of the aglycon was determined by X-ray crystallographic analysis.  相似文献   
82.
We investigated the spontaneous and phytohemagglutinin-stimulated production of interleukin-1 (IL-1) and tumor necrosis factor- (TNF-) by peripheral blood mononuclear cells in patients with chronic hepatitis C during treatment with interferon- (IFN-). Spontaneous productions of these were significantly higher in patients with chronic hepatitis C than in healthy subjects. For patients prescribed interferon, stimulated production of TNF- was significantly higher in complete responders than in partial responders, but the differences were small between the other cytokine levels and outcome of IFN treatment. Spontaneous production of these cytokines was higher in patients with genotype III with complete response than in genotype III patients with a partial response, but this was not the case in patients with genotype II. There was a negative correlation between these cytokines and histological activity index. Spontaneous production of cytokines was decreased only in complete responders after the administration of interferon. These data suggest that the elevated production of cytokines in patients with chronic hepatitis C may be due to host response to the virus, and monitoring cytokines along with alanine aminotransferase and hepatitis C virus RNA during treatment may provide more precise information of the effectiveness of therapy.  相似文献   
83.
In order to clarify the immunogenetical background, host factors in oncology, human leukocyte antigen (HLA) and tumor necrosis factor (TNF) beta alleles as prognostic, preventive and therapeutic indicators were investigated in 712 patients with a histologic diagnosis of adenocarcinoma of the stomach treated with gastrectomy. HLA and TNF beta alleles were tested serologically and by DNA-PCR typing. The absence of HLA Cw1 antigen may represent resistant and prognostic factors. HLA-B51, B61 and TNF beta 10.5 kb homozygote alleles are therapeutic, survival and prognostic factors. Considering the relation with lymph node metastasis, HLA-DR4 antigen and HLA-DRB 1*0405 allele were found to be risk factors for lymph node metastasis in poorly differentiated adenocarcinoma. TNF beta 10.5 kb homozygote allele also represented a risk factor for lymph node metastasis. TNF beta 5.5 kb homozygote allele was considered a resistant factor for lymph node metastasis in poorly differentiated adenocarcinoma. HLA and TNF beta alleles can play an important role as prognostic, preventive and therapeutic indicators in gastric cancer. Therefore, TNMH (TNM with host factor) should be proposed as a new approach.  相似文献   
84.
Neural cell adhesion molecule (NCAM) is an integral membrane glycoprotein that participates in cell-cell interactions. We examined the expression of neural cell adhesion molecule (NCAM) by immunohistochemistry in 65 cases of thyroid disease. In the majority of thyroid tumors, NCAM expression was detected in tumor cells. In chronic thyroiditis, Hurthle cells demonstrated expression of NCAM. In normal thyroid gland, neither follicular nor parafollicular cells expressed NCAM at detectable levels. All papillary carcinomas and most poorly differentiated follicular carcinomas and some follicular adenomas demonstrated NCAM expression. In thyroid carcinoma, clinical stage and recurrent laryngeal nerve paralysis did not correlate significantly with expression of NCAM. Papillary carcinomas with strong expression of NCAM were more likely to have extra capsular invasion. It is supposed that immunohistochemical detection of NCAM expression supports histologic diagnosis and offers prognostic information.  相似文献   
85.
We observed the attacks of nystagmus in a case of infantile spasms and carried out overnight sleep polygraphy. The following findings were obtained:
  • 1 Awake time was prolonged to 56% of TIB, while sleep time was markedly shortened to 44% of TIB. Also REM sleep time was reduced to 20% of SPT and deep slow sleep (stage N3) was absent.
  • 2 Attacks of nystagmus were observed only during wakefulness. At first, fast wave bursts appeared in the right occipital area, and were followed by left-upward deviations of eyeballs, and then the attacks of counterclockwise right-downward rotatory nystagmus. Also the fast wave bursts were succeeded by spreading of fast waves to adjacent areas. At the same time, EMG exhibited elevated muscle action potentials of mentalis and biceps fernoris. During the attacks of nystagmus, there was alteration of respiratory movements.
In NREM sleep, both fast wave bursts and the attacks of nystagmus were not observed. In REM sleep, the fast wave bursts and eye movements were observed but the attacks of nystagmus did not appear. During the fast wave bursts, alteration of respiratory movements were observed. From the results of this study, it was presumed that the brain lesions of this case were extended with severe degree of damage in the great parts of brain containing Cerebral cortex and brain stem.  相似文献   
86.
We analyzed linkage between HLA-DRB1 and -DRB3 types in 219 Japanese donors by oligonucleotide genotyping. In the Japanese population, DRB1*1201 was linked with DRB3*0101 in all donors analyzed; in contrast, most Caucasian DRB1*1201 is known to be linked with DRB3*02(01/02) (*0201 or *0202). However, most DRB1*1202 was linked with DRB3*0301. Thus, the two DRw12-related DRB1 types are linked with DRB3 types distinct from each other. All the three DRw14-related DRB1 types, DRB1*1401, DRB1*1402, and DRB1*1405, were linked with DRB3*02(01/02) in the Japanese population, contrasting with the known linkage between DRB1*1402 and DRB3*0101 in other ethnic populations. The serologically "blank" DR type, DRB1*1403, was linked with DRB3*0101. Other DRB1 types, DRB1*0301, DRB1*11(01/04) (*1101 or *1104), and DRB1*13(01/02) (*1301 or *1302) in the Japanese population were linked mostly with the same DRB3 types, like those known in other ethnic populations.  相似文献   
87.
In order to clarify the interaction of volatile anesthetics and extracellular calcium ion on the myocardial contraction, effects of both isoflurane (1.0%) and halothane (0.5%) on the extracellular calcium ion concentration ([Ca2+]O)-tension curve were studied. Increasing [Ca2+]O enhanced the myocardial contraction response, and the maximal response was obtained at [Ca2+]O of 3.0mM. Halothane depressed the maximal value of the tension development in response to increasing [Ca2+]O, while isoflurane did not (P 0.01). The probit response of the developed tension to the changes in [Ca2+]O indicated that isoflurane increased the median effective concentration (EC50) of [Ca2+]O significantly from 0.484 ± 0.051 (mean ± SEM) to 0.870 ± 0.056mM (P = 0.001), but halothane did not (P = 0.018). Therefore, 1.0% isoflurane was concluded to move the [Ca2+]O-tension curve to the right, while a downwards shift occurred with 0.5% halothane.(Saeki S, Hirakawa M, Shimosato S: Effects of Isoflurane and Halothane on the Calcium Ion-tension Curve in Rat Myocardium. J Anesth 6: 172–175, 1992)  相似文献   
88.
This is the first report of a patient with venous insufficiency following compressive arachnoiditis ossificans (AO). Symptoms of fluctuating monoplegia and sensory disturbance appeared monthly, lasting several weeks each time. Spinal magnetic resonance imaging (MRI) showed high T2-weighted signal intensity in the posterior portion of the column from T11 to T12 and an intradural lesion with low T2-weighted signal intensity. Neurological function and MRI improved markedly following an operation on AO. The symptoms seen in the present case were due to posterior venous insufficiency following compressive AO.  相似文献   
89.
We used magnetic resonance imaging (MRI) to evaluate bowleg deformities in infancy. Twenty-five tibiae of 13 infants were examined and divided into two groups based on MRI findings: group A had high intensity area in the medial epiphyseal cartilage on T2-weighted images. Group B had depression of medial physis and abnormal signal in the perichondrial region in addition to the epiphyseal lesion. At the final follow-up, all cases in group A demonstrated normal lower leg alignments, whereas five cases in group B showed characteristic roentogenographic findings of Blount's disease. The improvement rate of metaphyseal-diaphyseal angle was correlated with this classification. These findings suggested that abnormal findings in physis and perichondrial region might be preliminary findings in early stage of Blount's disease. The high intensity areas in the medial epiphyseal cartilage were commonly found among the cases with bowing deformities, which suggested that there might be a common pathomechanism between physiologic bowing and infantile Blount's disease.  相似文献   
90.
Elective neck clipping for unruptured aneurysms in elderly patients   总被引:1,自引:0,他引:1  
BACKGROUND: With the recent advancements of neuroimaging techniques, the number of unruptured aneurysms diagnosed in elderly patients has increased. However, the surgical indications in this special subgroup have not been studied critically. The purposes of this study were to analyze the results of elective neck clipping surgery for unruptured aneurysms in the elderly and to elucidate the surgical indications. METHODS: From 1985 to 1997, 96 patients, aged 70 years or older, with 103 unruptured cerebral aneurysms underwent elective neck clipping. There were 67 females and 29 males. Their ages ranged from 70 to 86, with a mean of 73.3 years. Seventy-five aneurysms were asymptomatic and 28 were symptomatic. The aneurysms were located on the internal carotid artery (46.6%), middle cerebral artery (35.9%), anterior cerebral artery (16.5%), and basilar artery (1.0%). RESULTS: The surgical outcome was a good recovery in 75 patients (78.1%), mild deficits in 12 (12.5%), severe deficits in 4 (4.2%), and death in 5 (5.2%). Recovery from preoperative symptoms with improved quality of life was seen in 22 (78.6%) of the 28 symptomatic cases. Multiple regression analysis showed that increase in the size of aneurysms and location on the middle cerebral artery and internal carotid artery were significantly related to a poor outcome. The causes of the five deaths were hemorrhagic infarction, systemic infection, and myocardial infarction. CONCLUSION: Surgery for elective neck clipping of unruptured aneurysms in the elderly should be considered in symptomatic patients with simple aneurysms that can be clipped without the use of temporary clips.  相似文献   
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