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41.
力学刺激对3月龄骨质疏松大鼠成骨细胞增殖与合成功能的影响 总被引:2,自引:0,他引:2
探讨周期性双轴力学应变对成骨细胞增殖与分化合成功能的影响。将正常 3月龄雌性 SD大鼠和骨质疏松大鼠颅顶骨分离的成骨细胞分别在含 10 %胎牛血清的 F- 12培养液中培养 ,并接种在双轴力学应变装置中。当细胞生长至亚融合状态 (Subconfluence) ,给细胞施加力学刺激 ,频率为 1Hz,力学刺激分别为 4 0 0、10 0 0、4 0 0 0μ strain;作用时间分别为每天 30 m in,2、4、8h,共加载两天。以未受力学刺激的细胞为对照组 ,受力学刺激的细胞为实验组 ,并进行比较。采用流式细胞技术测定细胞增殖变化 ;采用同位素标记方法检测成骨细胞骨钙素、I型胶原 C端前肽 (PICP)和总蛋白的分泌量。结果表明 :1)在静态培养条件下 ,3ovx组与 3control组比较 ,其细胞功能活性无明显变化 ,但 3ovx组大鼠成骨细胞增殖活性明显增高 ,这与绝经后骨质疏松骨代谢的高转换率相一致。 2 )4 0 0、10 0 0 μstrain力学刺激可以促进 3control组成骨细胞 I型胶原、骨钙素和总蛋白的分泌量增加 ,促进成骨细胞的分化成熟 ;在 10 0 0μstrain力学刺激下 ,成骨细胞合成骨基质的能力增加最为明显。同时 ,在 4 0 0、10 0 0μstrain力学刺激的初期也可以促进成骨细胞的增殖 ,而促进成骨细胞的分化成熟的作用大于促进细胞增殖的作用。 3)在4 0 0 0 μ 相似文献
42.
缺血性卒中或短暂性脑缺血发作患者的卒中预防指南 总被引:8,自引:0,他引:8
Ralph L.Sacco Robert Adams Grge Albers Mark J.ALBERTS Oscar Benavente Karen Furie Larry B.Goldstein Philip Gorelick Jonathan Halperin Robert Harbaugh S.Claiborne Johnston Irene Katzan Margaret Kelly-Hayes Edgar J.Kenton Michael Marks Lee H.Schwamm Thomas Tomsick 曹勇军 《中华脑血管病论坛》2006,4(1):21-66
这份新声明旨在为缺血性卒中或短暂性脑缺血发作存活者的缺血性卒中预防提供全面和及时的循证推荐,循证推荐包括对危险因素的控制,动脉粥样硬化性疾病的干预措施,心源性栓塞的抗栓治疗以及非心源性卒中抗血小板药的应用。另外,还为其他多种特殊情况下复发性卒中的预防提供了推荐、包括动脉夹层分离、卵圆孔未闭、高同型半胱氨酸血症、高凝状态、镰状细胞病、脑静脉窦血栓形成、女性卒中(特别是与妊娠和绝经后激素替代治疗相关卒中),脑出血后肮凝药的应用,以及该指南在高危人群中执行和应用的特殊措施。 相似文献
43.
Howard A Israel John Desmond Ward Brenda Horrell Steven J Scrivani 《Journal of oral and maxillofacial surgery》2003,61(6):662-667
PURPOSE: In this investigation, we evaluated a population of patients with chronic orofacial pain who sought treatment at a pain center in an academic institution. These patients were evaluated with respect to 1) the frequency and types of previous oral and maxillofacial surgery procedures, 2) the frequency of previous significant misdiagnoses, and 3) the number of patients who subsequently required surgical treatment as recommended by an interdisciplinary orofacial pain team. The major goal of this investigation was to determine the role of oral and maxillofacial surgery in patients with chronic orofacial pain. Patients and Methods: The study population included patients seen at the Center for Oral, Facial and Head Pain at New York Presbyterian Hospital from January 1999 through April 2001. (120 patients; female-to-male ratio, 3:1; mean age, 49 years; average pain duration, 81 months; average number of previous specialists, 6). The patient population was evaluated by an interdisciplinary orofacial pain team and the following characteristics of this population were profiled: 1) the frequency and types of previous surgical procedures, 2) diagnoses, 3) the frequency of previous misdiagnoses, and 4) treatment recommendations made by the center team. RESULTS: There was a history of previous oral and maxillofacial surgical procedures in 38 of 120 patients (32%). Procedures performed before our evaluation included endodontics (30%), extractions (27%), apicoectomies (12%), temporomandibular joint (TMJ) surgery (6%), neurolysis (5%), orthognathic surgery (3%), and debridement of bone cavities (2%). Surgical intervention clearly exacerbated pain in 21 of 38 patients (55%) who had undergone surgery. Diagnoses included myofascial pain (50%), atypical facial neuralgia (40%), depression (30%), TMJ synovitis (14%), TMJ osteoarthritis (12%), trigeminal neuralgia (10%), and TMJ fibrosis (2%). Treatment recommendations included medications (91%), physical therapy (36%), psychiatric management (30%), trigger injections (15%), oral appliances (13%), biofeedback (13%), acupuncture (8%), surgery (4%), and Botox injections (1%) (Allergan Inc, Irvine, CA). Gross misdiagnosis leading to serious sequelae, with delay of necessary treatment, occurred in 6 of 120 patients (5%). CONCLUSIONS: Misdiagnosis and multiple failed treatments were common in these patients with chronic orofacial pain. These patients often have multiple diagnoses, requiring management by multiple disciplines. Surgery, when indicated, must be based on a specific diagnosis that is amenable to surgical therapy. However, surgical treatment was rarely indicated as a treatment for pain relief in these patients with chronic orofacial pain, and it exacerbated and perpetuated pain symptoms in some of them. 相似文献
44.
H S Mao C Grau J Overgaard 《International journal of radiation oncology, biology, physics》1992,22(1):115-122
The interaction of irradiation, Misonidazole (MISO), and hyperthermia was studied in a C3H mouse mammary carcinoma and its surrounding skin in vivo. MISO (0.5-1.0 mg/g) was injected 30 min before irradiation. Hyperthermia (41.5 degrees-43.5 degrees C for 60 min) was given either simultaneously, 0.5 hr, or 4 hr after X rays. The results were evaluated as the radiation dose to achieve tumor control (TCD50) or moist desquamation of the skin (DD50) in half of the treated animals. A therapeutic gain was found when the enhancement in tumors were greater than that found in skin. The combination of simultaneous heat and irradiation caused great enhancement in radiation response, but with no therapeutic gain. A slightly lower enhancement of the damage in both tissues was found with a 30 min interval between irradiation and hyperthermia, whereas heat 4 hr after X rays gave a small, but significant therapeutic gain. MISO significantly enhanced the response in tumors but not in skin. Combined trimodality treatment with MISO, irradiation, and hyperthermia resulted in enhancement ratios up to 15, dependent on temperature, radiation-heat interval, and to a lesser extent the MISO dose. The enhancement was for all schedules most pronounced in the tumors, resulting in an improved therapeutic effect. The combination of MISO and hyperthermia may be a valuable addition to radiotherapy, especially if heat and irradiation can be applied with close interval and with one of the modalities given selectively to the tumor. 相似文献
45.
46.
Twenty-seven cases of metastatic tumor of posterior fossa were presented in this paper. Of the patients, 20 were males and 7 females; their age ranged from 20 to 68, and 89% of them were over 40 years of age. The primary foci found were bronchopulmonary carcinomas (7 cases), rhinopharyngeal carcinomas (3 cases), and cancer of the liver (1 case), but in 16 cases the primary foci were not found. All of these patients presented symptoms and signs of obviously increased intracranial pressure, and most of them had the signs of cerebellar and cranial nerves' lesions. Ventriculorgraphy and brain CT scanning were important procedures in the diagnosis, and MRI was most valuable in establishing the diagnosis and localization of posterior fossa metastatic tumors. Twenty-six patients underwent operation. The short-term follow-up study showed an improvement in 25 cases. There was one death. The surgical treatment of posterior fossa metastatic tumor was emphasized. Radiotherapy and chemotherapy were discussed. 相似文献
47.
48.
Cognitive impairment after stroke: frequency, patterns, and relationship to functional abilities. 总被引:15,自引:2,他引:13 下载免费PDF全文
T K Tatemichi D W Desmond Y Stern M Paik M Sano E Bagiella 《Journal of neurology, neurosurgery, and psychiatry》1994,57(2):202-207
Cognitive function was examined in 227 patients three months after admission to hospital for ischaemic stroke, and in 240 stroke-free controls, using 17 scored items that assessed memory, orientation, verbal skills, visuospatial ability, abstract reasoning, and attentional skills. After adjusting for demographic factors with standardised residual scores in all subjects, the fifth percentile was used for controls as the criterion for failure on each item. The mean (SD) number of failed items was 3.4 (3.6) for patients with stroke and 0.8 (1.3) for controls (p < 0.001). Cognitive impairment, defined as failure on any four or more items, occurred in 35.2% of patients with stroke and 3.8% of controls (p < 0.001). Cognitive domains most likely to be defective in stroke compared with control subjects were memory, orientation, language, and attention. Among patients with stroke, cognitive impairment was most frequently associated with major cortical syndromes and with infarctions in the left anterior and posterior cerebral artery territories. Functional impairment was greater with cognitive impairment, and dependent living after discharge either at home or nursing home was more likely (55.0% with, v 32.7% without cognitive impairment, p = 0.001). In a logistic model examining the risks related to dependent living after stroke, cognitive impairment was a significant independent correlate (odds ratio, OR = 2.4), after adjusting for age (OR = 5.2, 80 + v 60-70 years) and physical impairment (OR = 3.7, Barthel index < or = 40 v > 40). It is concluded that cognitive impairment occurs frequently after stroke, commonly involving memory, orientation, language, and attention. The presence of cognitive impairment in patients with strike has important functional consequences, independent of the effects of physical impairment. Studies of stroke outcome and intervention should take into account both cognitive and physical impairments. 相似文献
49.
Although it is known that rapid expansion of the vertebrate brain begins near the time that the spinal neurocoel is occluded, it still remains unknown when occlusion occurs in relation to neurulation. Since both morphogenetic events are critical for normal brain growth, it is important to decipher the temporal relationship between the two processes. This study assessed the temporal relationship of the two events with the rationale that if it could be demonstrated that occlusion occurs coincident with the completion of neurulation, then it could be argued that factors shown to direct neurulation could also initiate occlusion. Nearly 600 chick embryos (stages 9- through 12+) were cultured atop egg-agar, the caudal extent of neurulation determined, the cranial five pairs of somites removed and the neurocoels assessed for occlusion. In stage 9- through 10- chicks, neurulation of the spinal cord is incomplete. Stages 10 through 12+ exhibit neurulation and occlusion from the 8th to 19th somites. When lateral tissues were removed in embryos 8 through 10-, the neural folds became dysraphic whereas in embryos stage 10 and older, the folds remained fused dorsomedially and occluded. The only surgical manipulation that was found to prevent occlusion was elimination of the lateral tissues responsible for elevation and closure of the neural folds. Analysis of particular components of the lateral tissues essential for convergence, by treating embryos (n = 75) with chemicals known to degrade tissue-tissue bonds or specific components of the perineural matrix, indicated that more than 75% of the embryos treated with EDTA, EDTA plus Ca2+, trypsin, collagenase, or hyaluronidase exhibited little or no effect on convergence, dorsomedial fusion, and concomitant occlusion. 相似文献
50.