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41.
42.
The effects of intracellular Ca2+ (Ca2+i) on K+ currents in hippocampal cells were examined using acutely isolated cells obtained from adult guinea pigs. Whole-cell voltage-clamp recordings were carried out in a configuration that allowed a continuous perfusion of the intracellular medium. Recording media were made to block inward currents and allowed selective activation of K(+)-dependent outward currents. Voltage-dependent outward currents consisted of an initial rapidly decaying component followed by a sustained component. The time constant of decay of the transient current was about 25 msec, and previous studies (Numann et al., 1987) showed that the kinetic and pharmacological properties of this current closely resembled the A current recorded in invertebrate neurons (Connor and Stevens, 1971; Thompson, 1982). Intracellular perfusion of hippocampal cells with a solution containing elevated Ca2+ (about 4.5 x 10(-4) M) elicited outward currents at the holding potential (-45 to -55 mV) and produced changes in voltage-dependent K+ currents. The transient outward current (IA) activated by depolarization was suppressed with increases in Ca2+i. Delayed, sustained K+ currents were greatly potentiated. Data also showed that, among the 3 effects elicited by Ca2+i, suppression of IA was most sensitive to Ca2+i elevation. Previous results (Numann et al., 1987) showed that IA had a lower threshold (about -45 mV) than sustained currents (about -40 mV). By using low levels of depolarization (-40 mV), IA can be selectively activated, and the suppressive effect of Ca2+i on IA was confirmed on the kinetically isolated IA.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
43.
Therapy of human cervical carcinoma with monoclonal antibody-Pseudomonas exotoxin conjugates. 总被引:1,自引:0,他引:1
Pseudomonas exotoxin A (PE) linked to the F(ab')2 fragment of 1H10, a murine monoclonal antibody recognizing a carbohydrate epitope of a glycoconjugate expressed on the surface of human cervical carcinoma tumor cells, was evaluated for in vitro and in vivo activity. PE can kill cells by ADP-ribosylating elongation factor 2 thus inhibiting protein synthesis. Disulfide- as well as thioether-linked immunotoxins (1H10-PE) killed cervical carcinoma cells in vitro and were 20-160 times more inhibitory to target than to control cells. Cell killing was antibody mediated as demonstrated by the reduction of 1H10-PE growth inhibition to target CaSki cells by free 1H10 F(ab')2. In addition, a control antibody immunotoxin was nontoxic to CaSki cells. Thioether-linked 1H10-PE administered either i.v. or i.p. suppressed the growth of established solid s.c. cervical carcinoma tumors xenografted in nude mice for over 30 days. Treatment with antibody alone or a control immunotoxin had no significant effect on tumor growth. Administration of immunotoxin i.p. was associated with less toxicity than administration i.v., but i.v. injections were more effective at suppressing the growth of established solid tumors. 相似文献
44.
Xiaoguang Chen Yi Li Lei Wang Mark Katakowski Lijie Zhang Jieli Chen Yongxian Xu Subhash C. Gautam Michael Chopp 《Neuropathology》2002,22(4):275-279
Intravenous administration of human bone marrow stromal cells (hMSCs) after middle cerebral artery occlusion (MCAo) in rats provides functional benefit. We tested the hypothesis that these functional benefits are derived in part from hMSC production of growth and trophic factors. Quantitative sandwich enzyme‐linked immunosorbent assay (ELISA) of hMSCs cultured with normal and MCAo brain extracts were performed. hMSCs cultured in supernatant derived from ischemic brain extracts increased production of brain‐derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). These neurotrophins and angiogenic growth factors increased in a post‐ischemia time‐dependent manner. The hMSC capacity to increase expression of growth and trophic factors may be the key to the benefit provided by transplanted hMSCs in the ischemic brain. 相似文献
45.
随着护理高等教育的发展,越来越多的护理本科生将走向临床,从事护理工作;结合护理本科生的特点,通过一年有计划、有目标、有针对性地规范化培训,可以使新护士尽快适应医院环境,完成从学生到护士的角色改变,更好适应临床护理工作. 相似文献
46.
OBJECTIVE: To investigate the characteristics of the early stage treponema pallidum infected tissue in ear, nose, oropharynx and larynx and to raise relevance ratio of syphilis in nose and oropharynx and enhance doctor's self-protection awareness. METHODS: The histopathologic characteristics were studied by using HE staining, Warthin-Starry (W-S) staining was adopted to examine the treponema pallidum(TP) in lesion issue and its exudates smear for 12 cases biopsy tissues of suspicious syphilis. The diagnosis was confirmed by venereal disease research laboratory (VDRL), rapid plasma reagin circle test(RPR), treponema pallidum hemagglutination test(TPHA) and fluorescent treponemal antibody-absorption test (FTA-ABS). Treat with curing syphilis methods which published by nation. RESULTS: In the 12 cases mucous membrane specimen, the squamous epithelium proliferated, neutrophilic granulocyte infiltrated, within inherent membrane generous plasmacyte and lymphocyte infiltrated. W-S staining: plenty of treponema pallidum were found inside mucous membrane epithelium and exudate smear. Serology examination: 11 cases VDRL(++++), 7 cases RPR (+), 11 cases TPHA(+), 1 case FTA-ABS(+). After systemic treatment, 11 cases are clinically recovered. All patients serology become negative. CONCLUSION: W-S staining method can directly demonstrate histopathologic characteristics in early syphilis, in intrinsic membrane numerous plasmacyte infiltration. Combining with specific syphilis serology examination could increase diagnosis rate of syphilis in nose and oropharynx. 相似文献
47.
Directors of nursing at 23 nursing homes with Alzheimer's units in Southwestern Pennsylvania completed a self‐reported survey of 12 questions. Responses from the self‐administered questionnaires (100% response rate) revealed a wide variation in the staff categories assessing the oral health status of newly admitted residents with AD. The respondents described oral examinations that were incomplete when compared to the oral indicators listed in the Minimum Data Set. All nursing homes reported that oral hygiene was provided each day. The number of residents in a facility had a significant effect on the frequency of oral hygiene provided. Only 52% of the facilities reported yearly oral examinations for this population. According to the respondents, dental treatment was typically performed on‐site. The oral health care costs were paid by Medicare, Medicaid, the residents/family members, or by other undescribed resources. Insufficient time, staff, and training, as well as uncooperative behavior, were identified as barriers to optimum oral health care for residents with AD. Additional staff, specialized training, and increased government reimbursement were suggested to improve the oral health care for this group of older adults. For future studies, review of medical records and on‐site evaluation of the oral health care at these facilities should be required to verify the reported practices. 相似文献
48.
49.
通过深入分析我国中医药科学性研究中所存在的问题,依据协同学理论,提出了中医药科学性的理论基础是协同学的观点。基于此,阐释了中医药科学性的协同学解释,这在一定意义上为中医药科学性的研究提供了新的视角和有益的启示。 相似文献
50.
Anterior mediastinal immature teratoma with precocious puberty in a child with Klinefelter syndrome.
Pen-Hua Su Shi-Ping Luh Da-Mien Yieh Jia-Yuh Chen Suh-Jen Chen Huei-Mei Hung Pei-Fen Liao 《台湾医志》2005,104(8):601-604
ABSTRACT: Klinefelter syndrome occurs in approximately 1 in 1000 males. A 4-year-old boy presented with precocious puberty and an anterior mediastinal mass. Serum alpha-fetoprotein and human chorionic gonadotropin levels were mildly increased. Computed tomography revealed a germ cell tumor (GCT) of the mediastinum. Complete resection of the tumor was performed. Histologic analysis revealed an immature teratoma. Males with Klinefelter syndrome develop GCTs at a rate 50 times higher than unaffected males. This case report calls attention to the need to rule out Klinefelter syndrome in boys who present with precocious puberty and a mediastinal GCT. 相似文献