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991.
In order to find a new class of anti-Helicobacter pylori (H. pylori) agents, a series of 4-[(3-acetamido)phenyl]-2-(substituted guanidino)thiazoles and some structurally rigid analoges were synthesized and evaluated for antimicrobial activity against H. pylori. Among the compounds obtained, high anti-H. pyrori activities were observed in benzyl derivative 34 (MIC = 0.025 microg/mL) and phenethyl derivatives 35 and 36 (MIC = 0.037 microg/mL and 0.017 microg/mL). Though alkyl derivatives generally showed lower activity, the 2-methoxyethyl derivative 28 preserved significant activity (MIC = 0.32 microg/mL) and also exhibited more potent gastric antisecretory activity than ranitidine. Structural restriction by bridging between the thiazole and the phenyl rings with an alkyl chain did not improve the activity in this series.  相似文献   
992.
993.
We studied the immune profiles of 21 Japanese hemophiliac patients who had been infected with human immunodeficiency virus type 1 (HIV-1) by the blood preparations during the 1982-84 period, and carried out the genotyping of HIV-1 V3 region for uncultivated peripheral blood mononuclear cells (PBMC) from 8 patients. Ten years after infection, asymptomatic carrier (AC, 14 cases) yet outnumbered those in AIDS related complex (ARC, 4 cases) and AIDS (3 cases), and the CD4+ and CD8+ T-cell numbers were not correlated with clinical stages. Macrophage tropic sequences, as identified according to the known tropism determinants, appeared to be more frequent as the CD4+ T-cell numbers were higher. There was no correlation of the cell tropism with the disease stages, however. It might be due to HIV-1 of CD4+ T-cells being more productive. The mutation in the V3 region appears to differentially influence the escape from antibody attack and clinical stages, and the cell tropism may not be related to the cell immunity of the host.  相似文献   
994.
A 64-year-old man underwent a medical checkup in May 1996 and was evaluated as class V using sputum cytology. Chest X-ray examination, bronchoscopy and chest computed tomography (CT) demonstrated no abnormalities. Thereafter, the patient was followed up with chest X-ray, bronchoscopy and chest CT at 3-month intervals. In December 1996, chest CT showed an increased density at the mediastinal side of the left upper bronchus, B1+2. There were no findings on bronchoscopy, but subsequent exfoliative cytology demonstrated keratinized malignant cells in samples obtained from left upper bronchus, B1+2. Although, it was difficult to identify localization of the tumor, left upper lobectomy was performed and the diagnosis of squamous cell carcinoma in situ was finally made. Here, we report on the course of this patient and discuss the diagnostic usefulness of sputum cytology as well as the pathogenesis of lung squamous cell carcinoma.  相似文献   
995.
Factors relating alterations in plasma and urine composition to recurrence of urinary stones during drug therapy were investigated by using a multiple regression analysis technique. These factors were influenced not only by the efficacy of the drugs but also by other factors (plasma or urinary constituents and overall health of the patients, etc.). In order to study the effect of drug therapy or other treatment on the alteration of plasma and urine constituents, multiple regression analysis is more appropriate than Student's pairedt-test which has been used by some workers. These two analytical methods yield different results even if used on the same data.  相似文献   
996.
997.
Fiber connections of the lateral valvular nucleus were investigated in a percomorph teleost, the tilapia (Oreochromis niloticus), by tract-tracing methods. Following tracer injections into the lateral valvular nucleus, neurons were labeled in the ipsilateral dorsal part of dorsal telencephalic area, corpus glomerulosum pars anterior, dorsomedial thalamic nucleus, central nucleus of the inferior lobe, mammillary body, semicircular torus, valvular and cerebellar corpus, in the bilateral rostral regions of the central part of dorsal telencephalic area, dorsal region of the medial part of dorsal telencephalic area, habenula, anterior tuberal nucleus, posterior tuberal nucleus, and spinal cord, and in the contralateral lateral funicular nucleus. Labeled fibers and terminals were found in the ipsilateral cerebellar corpus and bilateral valvula of the cerebellum. Tracers were injected into portions of the telencephalon, pretectum, inferior lobe, and cerebellum to confirm reciprocally connections with the lateral valvular nucleus and to determine afferent terminal morphology in the lateral valvular nucleus. Telencephalic fibers terminated mainly in a dorsolateral portion of the lateral valvular nucleus. Terminals from the corpus glomerulosum pars anterior, central nucleus of the inferior lobe, and mammillary body showed more diffuse distributions and were not confined to particular portions of the lateral valvular nucleus. Labeled terminals in the lateral valvular nucleus were cup-shaped or of beaded morphology. These results indicate that the lateral valvular nucleus receives projections from various sources including the telencephalon, pretectum, and inferior lobe to relay information to the valvular and cerebellar corpus. In addition, the corpus glomerulosum pars anterior in tilapia is considered to be homologous to the magnocellular part of superficial pretectal nucleus in cyprinids.  相似文献   
998.
Mutations of the p53 gene in lymphoid leukemia.   总被引:4,自引:0,他引:4  
  相似文献   
999.
FT-207 or UFT was administered preoperatively to 74 patients with gastric cancer. The 5-FU and FT-207 concentrations in the serum and various tissues were investigated. The 5-FU concentration in various tissues was higher than in the serum after the administration of FT-207 or UFT. Especially it showed that 5-FU concentration in tumor was highest in other normal tissues. The 5-FU concentration in the tumor for the UFT group was higher than for the FT-207 group. There was a significant difference between the UFT and FT-207 groups (P less than 0.05). Levamisole had no influence on the concentration of 5-FU.  相似文献   
1000.
Extraskeletal myxoid chondrosarcoma arising from the retroperitoneum   总被引:1,自引:0,他引:1  
A case of extraskeletal myxoid chondrosarcoma is presented. The tumor occurred in the retroperitoneum and systemic metastases were found at autopsy. The primary and metastatic tumors were soft and strikingly myxoid on gross appearance. Microscopic observation revealed undifferentiated malignant tumor having large amounts of myxoid substance and a small amount of well-differentiated chondrosarcoma element in the primary lesions. The authors obtained an immunohistochemical result that the tumor cells showed positivity for alpha-1-antitrypsin and alpha-1-antichymotrypsin. Regarding S-100 protein, the well-differentiated chondrosarcoma element revealed intense positivity, whereas the poorly differentiated myxoid areas were not positive except for a few tumor cells. This is the first case, to our knowledge, of extraskeletal myxoid chondrosarcoma arising from the retroperitoneum, and immunohistologic findings suggest that alpha-1-antitrypsin and alpha-1-antichymotrypsin may be available markers in poorly differentiated chondrosarcomas showing a negative reaction for S-100 protein.  相似文献   
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