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111.
The modifying effects of oltipraz on induction of glandular stomach carcinogenesis by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in a total of 120 male 6-week-old Wistar rats, divided into six groups. Groups 1-3 (30 animals each) were given 100 p.p.m. MNNG in their drinking water for 10 weeks as an initiation treatment for gastric cancer induction and respectively fed diets supplemented with 0.04%, 0.02% and 0% oltipraz for 12 weeks, starting 1 week before and finishing 1 week after the carcinogen exposure. Groups 4-6 (10 animals each) were similarly treated without the application of MNNG. At the end of the 80th experimental week, all surviving animals were autopsied and examined histopathologically for the existence of gastric proliferative lesions. The incidence and multiplicity of adenocarcinomas were significantly (P < 0.01) lower in group 1 than in group 3. In addition, the multiplicity of atypical hyperplasias in the pyloric region was significantly (P < 0.05) decreased in group 1 as compared with the group 3 value. No gastric proliferative lesions were found in groups 4-6. In an additional short-term experiment, oltipraz significantly reduced cell proliferative activity (P < 0.01) and elevated glutathione levels (P < 0.05) in the glandular stomach mucosa of rats treated with MNNG. Thus our results clearly indicate that oltipraz can inhibit induction of proliferative glandular stomach lesions by MNNG in the rat.   相似文献   
112.
COVID‐19 infection can be a possible trigger for peripartum cardiomyopathy. Multidisciplinary teamwork was crucial for the favorable outcome in our patient. Small bowel strangulation is a rare complication post‐cesarean section.  相似文献   
113.
Total anomalous pulmonary venous drainage is a rare congenital anomaly. It usually involves a pulmonary to systemic venous shunt and most cases have a septal defect in order to survive. Anomalous pulmonary venous drainage with pulmonary venous shunting is an extremely rare and entirely benign entity. We present two such cases, in which there was atresia of the left superior pulmonary vein and drainage via a tortuous collateral vein to the left inferior pulmonary vein. This collateral was mistaken on plain film and CT for a pulmonary arteriovenous malformation. Awareness of this anomalous unilateral single pulmonary vein and its radiological appearances may help in avoiding unnecessary pulmonary angiography.  相似文献   
114.
Mild hyperhomocysteinaemia is a major risk factor for vascular disease and neural tube defects (NTDs), conferring an approximately three-fold relative risk for each condition. It has several possible causes: heterozygosity for rare loss of function mutations in the genes for 5,10-methylene tetrahydrofolate reductase (MTHFR) or cystathionine-&bgr;-synthase (CBS); dietary insufficiency of vitamin co-factors B6, B12 or folates; or homozygosity for a common 'thermolabile' mutation in the MTHFR gene which has also been associated with vascular disease and NTDs. We quantified the contribution of the thermolabile mutation to the hyperhomocysteinaemic phenotype in a working male population (625 individuals). Serum folate and vitamin B12 concentrations were also measured and their relationship with homocysteine status and MTHFR genotype assessed. The homozygous thermolabile genotype occurred in 48.4, 35.5, and 23.4% for the top 5, 10 and 20% of individuals repectively) ranked by plasma homocysteine levels, compared with a frequency of 11.5% in the study population as a whole establishing that the mutation is a major determinant of homocystein levels at the upper end of the range. Serum folate concentrations also varied with genotype, being lowest in thermolabile homozygotes. The MTHFR thermolabile genotype should be considered when population studies are designed to determine the effective homocysteine-lowering dose of dietary folate supplements, and when prophylactic doses of folate are recommended for individuals.   相似文献   
115.
AnewratmodelofportalhypertensioninducedbyintraportalinjectionofmicrospheresLIXiangNong1,ISBenjamin2andBAlexander2Subjecthead...  相似文献   
116.
目的 了解氯喹单用及与青蒿琥脂伍用治疗恶性疟前后 ,pfcrt和 pfmdr1抗药性有关基因的点突变变化特征。  方法 使用PCR RFLP技术检测基因点突变。 结果 氯喹及与青蒿琥脂伍用治疗前后的所有样本都发现有恶性疟原虫pfcrt基因氨基酸编码 76突变为苏氨酸的特征。但是 ,氯喹治疗前 ,5 0 % pfmdr1基因氨基酸编码 86为天冬酰氨酸 (野生型 ) ,而剩余的 5 0 %为野生型和突变型 (苏氨酸 )的特征。氯喹治疗后 ,在 18个复燃的病例中 ,83 .3 %的 pfmdr1基因 86位点为野生型 ,剩余的 16.7%是混合型。氯喹与青蒿琥脂伍用治疗前 ,3个样本携带混合型基因型 ,剩余的 (86% )为野生型 ,但治疗后 ,所有样本只携带野生型。 结论 这些结果可能支持这样的假说 :pfcrt基因突变起主导作用 ,但 pfmdr1基因突变增强了氯喹抗药性的效果。  相似文献   
117.
We previously reported isolation of human T-cell leukemia virus II (HTLV-II) from a second patient (N.R.A.) with atypical hairy cell leukemia. Follow-up analysis of the characteristics of the patient's HTLV-II infection over a 2-year period has revealed that the patient had two coexistant lymphoproliferative disorders. Oligoclonally integrated HTLV-II was detected in DNA extracted from the patient's peripheral blood mononuclear cells on separate occasions greater than 1 year apart, similar to integration of HTLV-I seen in adult T cell leukemia/lymphoma. Although integrated provirus was readily detected, no HTLV-II viral RNA expression was seen in fresh peripheral blood lymphoid cells. Although the patient's peripheral blood consistently contained a majority of atypical lymphoid cells with a T cell antigenic phenotype, he ultimately developed extensive pleural, hepatic and soft tissue infiltration with malignant Tac+, tartrate-resistant, acid phosphatase-positive (TRAP+) B cells of clonal origin. To further characterize the role of HTLV-II, the patient's peripheral blood mononuclear cells were fractionated into four enriched subpopulations at autopsy. Oligoclonally integrated HTLV-II was detected in DNA from a T cell-enriched fraction and a CD8+ T cell-enriched fraction, but not in a CD4+ T cell-enriched fraction, a non-T cell fraction, or in B cells obtained from the malignant pleural effusion. We conclude that the patient harbored two distinct lymphoproliferative disorders, a TRAP+, Tac+ B cell malignancy consistent with hairy cell leukemia that did not contain HTLV-II and a Tac-, CD8+ lymphoproliferative syndrome with oligoclonally integrated HTLV-II.  相似文献   
118.
Human T-cell leukemia virus type I (HTLV-I) is recognized as the etiologic agent of adult T-cell leukemia (ATL), a disease endemic in certain regions of southeastern Japan, Africa, and the Caribbean basin. Although HTLV-I can immortalize T lymphocytes in culture, factors leading to tumor progression after HTLV-I infection remain elusive. Previous attempts to propagate the ATL tumor cells in animals have been unsuccessful. Severe combined immunodeficient (SCID) mice have previously been used to support the survival of human lymphoid cell populations when inoculated with human peripheral blood lymphocytes (PBL). SCID mice were injected intraperitoneally with PBL from patients diagnosed with ATL, HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), or from asymptomatic HTLV-I-seropositive patients. Many of these mice become persistently infected with HTLV-I. Furthermore, after human reconstitution was established in these mice, HTLV-I-infected cells displayed a proliferative advantage over uninfected human cells. Lymphoblastic lymphomas of human origin developed in animals injected with PBL from two ATL patients. The tumor cells represented outgrowth of the original ATL leukemic clone in that they had monoclonal or oligoclonal integrations of the HTLV-I provirus identical to the leukemic clone and predominantly expressed the cell surface markers, CD4 and CD25. In contrast, cell lines derived by HTLV immortalization of T cells in vitro did not persist or form tumors when inoculated into SCID mice, indicating differences between in vitro immortalized cells and ATL leukemic cells. This system represents the first small animal model to study HTLV-I tumorigenesis in vivo.  相似文献   
119.
120.
Summary The authors report a case of total persistence of the hyoïdo-stapedial artery (HSA) discovered fortuitously in an adult. The external carotid artery terminated as the superficial temporal, middle deep temporal and transverse facial arteries; the HSA arose from the intrapetrous internal carotid artery, coursed within the middle ear and the middle cranial fossa where it gave off the middle meningeal artery before leaving the skull via the foramen spinosum to become the maxillary artery.
Persistance complète de l'artère hyoïdo-stapédienne chez l'homme: à propos d'un cas (origine carotidienne intrapétreuse de l'artère maxillaire)
Résumé Les auteurs rapportent un cas de persistance totale de l'artère hyoïdo-stapédienne (AHS) de découverte fortuite chez un adulte. L'artère carotide externe se termine en artère temporale superficielle, temporale moyenne profonde et transverse de la face; l'AHS naît de la carotide interne intrapétreuse, chemine à l'intérieur de l'oreille moyenne et de la fosse cérébrale moyenne où elle abandonne l'artère méningée moyenne avant de quitter le crâne en passant par le trou petit rond pour devenir l'artère maxillaire.
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