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61.
I-J as an Inducible T Cell Receptor for Self   总被引:4,自引:0,他引:4  
"Jedenfalls, wenn man davorsteht, dann sieht man sich selbstaber eben nicht wie in einem gewöhnlichen Spiegel, versteht sich. Man sieht nicht sein Äusseres, sondern man sieht sein wahres inneres Wesen. so wie es in Wirklichkeit beschaffen ist. Wer da durch will, der muß - um es mal so auszudrücken -in sich selbst hineingehen."
Die undendliche Geschichte, bei Michael Ende, K. Thiehemanns Verlag, Stuttgart, 1979.  相似文献   
62.
The avoidance behavior of fish is a sensitive indicator to aquatic contaminants such as surfactants, pesticides, and residual chlorine. This paper describes an avoidance test with special reference to monochloramine by medaka (killifish,Oryzias latipes) in a small modular chamber system with a symmetrical parallel-flow. The significant avoidance concentration (P = 0.05) was 5.7 g/L as combined residual chlorine, which is the lowest among the residual chlorine avoidance concentrations reported in the literature. The avoidance curves of medaka to monochloramine exhibited a similar pattern to those of anionic surfactants.  相似文献   
63.
Malnutrition negatively affects the quality of life of patients with dysphagia. Despite the need for nutritional status assessment in patients with dysphagia, standard, effective nutritional assessments are not yet available, and the identification of optimal nutritional assessment items for patients with dysphagia is inadequate. We conducted a scoping review of the use of nutritional assessment items in adult patients with oropharyngeal and esophageal dysphagia. The MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials databases were searched to identify articles published in English within the last 30 years. Twenty-two studies met the inclusion criteria. Seven nutritional assessment categories were identified: body mass index (BMI), nutritional screening tool, anthropometric measurements, body composition, dietary assessment, blood biomarkers, and other. BMI and albumin were more commonly assessed in adults. The Global Leadership Initiative on Malnutrition (GLIM), defining new diagnostic criteria for malnutrition, includes the categories of BMI, nutritional screening tool, anthropometric measurements, body composition, and dietary assessment as its required components, but not the blood biomarkers and the “other” categories. We recommend assessing nutritional status, including GLIM criteria, in adult patients with dysphagia. This would standardize nutritional assessments in patients with dysphagia and allow future global comparisons of the prevalence and outcomes of malnutrition, as well as of appropriate interventions.  相似文献   
64.
Posterior stabilization is a common surgical procedure, which aims for rigid stabilization by facet fusion. Facet non-union has a potential risk of the screw loosening and malalignment. Although some authors have reported the influencing factors about screw loosening in the lumbar spine, there are few reports about the risk factor contributing to the facet non-union in the cervical spine. In all, 22 patients (78 facets and 122 screws) with degenerative cervical kyphosis or spondylolisthesis who underwent decompression and lateral mass screw (LMS) fixation were analyzed. Age, gender, smoking, bone mineral density (BMD), the degree of facet decortication with bone packing, and screw loosening were investigated as risk factors contributing to the facet non-union at each segmental fused level. Facet fusion rate was 85.9% (67/78 facets) and the incidence of loosening was 4.9% (6/122 screws, 4 patients). Insufficient facet decortication with bone packing is a significant risk factor of facet non-union (p <0.05, odds ratio: 26.5). All six loosened screws were associated with bony non-union of the facet and were located in the uppermost or lowermost vertebrae. Comparing loosened screws and stable screws, the average maximal insertional screw torque (MIT) was 9.8 cNm and 39.5 cNm, respectively (p <0.05). Additionally, the length of the stable screws was significantly longer versus the loosened screws (p <0.05). Lower MIT and shorter screw length located near the ends of the lateral mass may predict loosening, which can lead to facet non-union. Sufficient facet decortication with bone packing is one of the important factors contributing to the facet fusion.  相似文献   
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A case of adamantinoma of the tibia is reported. A 70-year-old man complained of a painful swelling over the lower front of the right tibia. Roentgenograms showed an oval well-circumscribed, multilocular cystic lesion. Curettage and bone grafting were performed, and 17 months later the patient is in good condition. Microscopically the tumor tissue consisted mainly of epithelial Islands with a palisading at the periphery and a loose reticular pattern in the center of the tumor cell nests, showing a close resemblance to the ameloblastoma of the jaw bones. Electron micrographs revealed the epithelial nature of the tumor cells, i.e., a continuous basal lamina, desmosomes and bundles of microfilaments, probably tonofilaments. One hundred fifty six cases of this peculiar primary skeletal bone tumor previously reported in the literature were reviewed and discussed.  相似文献   
68.
Retinoblastomas exhibit a unique form of differentiation to produce cell elements similar to those seen in a photoreceptor cell. An ultrastructural study was performed on 29 cases of retinoblastoma to further clarify the cytologic characteristics of the tumor cells. The age of the retinoblastomas averaged 17.1 months and the tumor cells showing photo-receptor differentiation were demonstrated in 10 cases (35%). The findings were especially notable in retinoblastomas with Flexner-Wintersteiner rosette formation (seven cases, 28%). Similar photoreceptor differentiation was also evident in solid cell clusters without rosette formation (four cases, 14%). The presence of photoreceptor elements was assumed to be significantly frequent both in Flexner-Wintersteiner rosettes and in the solid cell clusters. The cell cytoplasm also showed proliferation of long mitochondria and microtubules, reflecting photoreceptor differentiation. The hereditary-type retinoblastoma showed more advanced cell differentiation than the non-hereditary type. Photoreceptor differentiated retinoblastoma showed rather indolent growth compared with the undifferentiated type, and the former can expect a curative treatment by operation. These observations provide additional findings of the biological nature of retinoblastomas.  相似文献   
69.
The effects of butorphanol injection on baroreflex control of heart rate were investigated using both pressor and depressor tests in eighteen adult patients. Baroreflex sensistivity was attenuated after butorphanol injection in the pressor test using phenylephrine, whereas it was unchanged in the depressor test using nitroglycerine. No resetting of the baroreflex occurred after butorphanol injection. After the administration of butorphanol, plasma epinephrine and norepinephrine levels increased. These results suggest that it is safe to use butorphanol clinically even when a reduction in blood pressure due to hypovolemia or unclamping of the major artery is expected and that it is disadvantageous to administer the drug when an increase in blood pressure due to cross-clamping of the major artery is predicted.(Wajima Z, Inoue T and Ogawa R: The effects of butorphanol on baroreflex control of heart rate in man. J Anesth 7: 411--418, 1993)  相似文献   
70.
Breast conserving surgery and radiation therapy (RT) can achieve a more favorable cosmetic outcome than mastectomy in patients with early breast cancer. However, it is widely recognized that RT is an impediment to improving the cosmetic outcome. Between 1985 and 1993, 113 patients were enrolled in a prospective randomized study to examine whether or not RT could be avoided following sector resection in patients with Stage I and II (UICC) invasive breast cancer. There was no significant difference in the 8 year local recurrence free survival rate between the RT and non-RT groups (92.3% versus 89.8% respectively). The characteristics of suitable patients would be negative nodes and microscopically negative resection margins. In conclusion, sector resection without RT is a reasonable option for some patients with early breast cancer.  相似文献   
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