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排序方式: 共有1113条查询结果,搜索用时 15 毫秒
991.
Effect of A3 pulley and adjacent sheath integrity on tendon excursion and bowstringing@Xie RG 相似文献
992.
993.
An unusual complication in a patient with Crohn enterocolitis is presented. Ultrasound and computed tomographic studies showed stationary gas in the portal vein, and a presumptive diagnosis of septic ascending portal thrombophlebitis was made. Emergency laparotomy was performed and the terminal ileum was excised for recurrent Crohn disease. Pathologic examination showed a fistula from the lumen of the inflamed segment to the superior mesenteric venous system. Autopsy 1 month later showed organizing thrombi and fecal debris in the portal venules. 相似文献
994.
A L Hoffman L Makowka D V Cramer X Cai A Pascualone B F Banner D G Sheahan P Rettinger T E Starzl 《Journal of investigative surgery》1989,2(3):241-251
Graft versus host disease (GVHD) may be abrogated and host survival prolonged by in vitro depletion of T lymphocytes from bone marrow (BM) prior to allotransplantation. Using a mouse anti-rat pan T-lymphocyte monoclonal antibody (OX19) bound to monosized, magnetic, polymer beads, T lymphocytes were removed in vitro from normal bone marrow. The removal of the T lymphocytes was confirmed by flow cytometry. Injection of the T-lymphocyte-depleted bone marrow into fully allogeneic rats prevents the induction of GVHD and prolongs host survival. 相似文献
995.
V. A. I. Natale J. F. Caffrey B. J. Sheahan G. J. Atkins 《Neuropathology and applied neurobiology》1993,19(6):530-534
Immunogold-silver staining of mixed rat cerebellar neuron/glial cell cultures, using Ranscht monoclonal antibody, resulted in labelling of neuronal processes and oligodendrocytes. This antibody was originally believed to react with galactocerebroside alone, and it was concluded that labelling by it resulted from the presence of myelin [2]. Electron microscopic examination of the cultures did not reveal myelination. Infection of such cultures with rubella virus resulted in a cytopathic effect. This effect was initially characterized as a disaggregation of neuronal processes, and the disruption of a layer of membranous material covering both cell bodies and processes. The virus causes disruption of cultures of pure glial cells, but there is no evidence of virus multiplication or cytopathic effect in pure neuron cultures. The cytopathic effect in mixed neuron/glial cell cultures is concluded to be glial cell mediated. 相似文献
996.
Cysteine endopeptidase activity levels in normal human tissues, colorectal adenomas and carcinomas 总被引:5,自引:0,他引:5
S Shuja K Sheahan M J Murnane 《International journal of cancer. Journal international du cancer》1991,49(3):341-346
We have assayed cysteine endopeptidase activities in 17 types of normal human tissue and in matched sets of colorectal mucosa, adenoma and carcinoma samples. Our data indicate that cathepsin B enzyme levels vary 70-fold and cathepsin L enzyme levels vary 20-fold from one normal tissue to another. Cathepsin B specific activity in normal tissues fell into 3 categories. High activity, with a mean of 156.7 +/- 41.5 nmoles min-1 mg-1 protein, was measured in liver, thyroid, kidney and spleen; intermediate activity, with a mean of 60.2 +/- 8.3 nmoles min-1 mg-1 protein, was measured in heart, colon, adrenal and lung; and low activity, with a mean of 18.4 +/- 9.7 nmoles min-1 mg-1 protein, was measured in prostate, testis, nerve, stomach, pancreas, brain, skeletal muscle, skin and breast. Cathepsin L specific activity fell into 2 categories. High activity, with a mean of 51.1 +/- 4.9 nmoles min-1 mg-1 protein, was measured in thyroid, liver and kidney; and low activity, with a mean of 11.4 +/- 5.5 nmoles min-1 mg-1 protein, was measured in spleen, colon, heart, adrenal, lung, testis, brain, nerve, skin, stomach, pancreas, skeletal muscle, prostate and breast. Our characterization of these enzyme levels provides a reference standard for normal cathepsin B and L activities in human tissues that should enhance the detection of their deregulation in disease states. For example, in studies of colorectal carcinoma and normal mucosa, we observed a significant tumor-specific increase in cathepsin B and L activities with particularly high activity levels in earlier (Dukes' A and B) compared to later (Dukes' C and D) stages of colorectal cancer. In contrast, adenomas from colorectal cancer patients expressed normal levels of cathepsin B activity, providing evidence that the increase in expression of cathepsin B may be a sensitive marker for progression from the pre-malignant to the malignant state in the development of colorectal cancer. 相似文献
997.
Li Liu Sheahan Bestel Jinming Shi Yanhua Song Xingcan Chen 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(14):5380-5385
Three grinding stones from Shizitan Locality 14 (ca. 23,000–19,500 calendar years before present) in the middle Yellow River region were subjected to usewear and residue analyses to investigate human adaptation during the last glacial maximum (LGM) period, when resources were generally scarce and plant foods may have become increasingly important in the human diet. The results show that these tools were used to process various plants, including Triticeae and Paniceae grasses, Vigna beans, Dioscorea opposita yam, and Trichosanthes kirilowii snakegourd roots. Tubers were important food resources for Paleolithic hunter–gatherers, and Paniceae grasses were exploited about 12,000 y before their domestication. The long tradition of intensive exploitation of certain types of flora helped Paleolithic people understand the properties of these plants, including their medicinal uses, and eventually led to the plants'' domestication. This study sheds light on the deep history of the broad spectrum subsistence strategy characteristic of late Pleistocene north China before the origins of agriculture in this region. 相似文献
998.
We describe a simple method that uses patient positioning to obtain oblique views of the human heart by magnetic resonance (MR) imaging. These views provide MR images that directly correlate with conventional anterior or posterior oblique radiography. 相似文献
999.
1000.
Measurement of right and left ventricular volumes in healthy individuals with cine MR imaging 总被引:18,自引:0,他引:18
Cine magnetic resonance (MR) imaging is a new, rapid MR pulse sequence that acquires up to 32 images per cardiac cycle at up to four levels of the heart within 4 minutes. In this study, the whole heart was encompassed by contiguous 10-mm transverse sections. Ventricular volumes were calculated by adding luminal areas determined in each section at end-diastole and end-systole. The left ventricular volume index was 57 ml/m2 +/- 9 at end-diastole and 17 ml/m2 +/- 4 at end-systole. The right ventricular volume index was 63 ml/m2 +/- 9 at end-diastole and 22 ml/m2 +/- 6 at end-systole. The left to right ventricular stroke volume ratio was 0.97 +/- 0.06, which was not statistically different from the theoretically expected ratio of 1. Interobserver and intraobserver measurements were closely correlated. Volume measurements were validated with two-dimensional echocardiography in five volunteers. Cine MR imaging allows reproducible three-dimensional measurement of right and left ventricular volumes with short imaging time and good temporal resolution. 相似文献