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61.
肛直肠抑制反射时门静脉血中P物质变化 总被引:1,自引:0,他引:1
目的探讨肛直肠抑制反射(RAIR)时门静脉血中P物质(SP)的变化规律及外源性内脏神经对其变化的影响。方法将实验大白鼠分为7组,其中6组先按去与不去直肠肛管外源性内脏神经支配而分为不去神经和去神经两大组,每组中又按Foley导管上气囊置入直肠腔中的位置分为2、4、6cm组;同时再设1个对照组,将Foley导管置入直肠腔中,但不注水扩张球囊。检测并比较在直肠腔内刺激后,各组门静脉血中的SP值及变化情况。结果去神经组中2、4cm组与不去神经组之间及对照组之间,门静脉血中SP值变化比较,P〉0.05,差异无统计学意义。不去神经组中的6cm组与对照组及去神经组中2cm和4cm组之间SP值比较,P〈0.01,差异有统计学意义;去神经组和不去神经组中的6cm组之间SP值比较,P〈0.01,差异有统计学意义。结论直肠腔内上部的刺激不引出RAIR可能与该部位的刺激使内括约肌兴奋性递质(SP)的释放有关;外源性内脏神经对RAIR中门静脉血的SP变化有调控作用。 相似文献
62.
Weiping Ren Bin Wu Xin Peng Jing Hua Hsiao-Nan Hao Paul H Wooley 《Journal of orthopaedic research》2006,24(8):1575-1586
Signaling of RANK (receptor activator of nuclear factor kappa B) through its ligand RANKL appears critical in osteolysis associated with aseptic loosening (AL). The purpose of this study was to investigate the role of RANK in a murine osteolysis model developed in RANK knockout (RANK(-/-)) mice. Ultra high molecular weight polyethylene (UHMWPE) debris was introduced into established air pouches on RANK(-/-) mice, followed by implantation of calvaria bone from syngeneic littermates. Wild type C57BL/6 (RANK(+/+)) mice injected with either UHMWPE or saline alone were included in this study. Pouch tissues were collected 14 days after UHMWPE inoculation for molecular and histology analysis. Results showed that UHMWPE stimulation induced strong pouch tissue inflammation in RANK(-/-) mice, as manifested by inflammatory cellular infiltration, pouch tissue proliferation, and increased gene expression of IL-1beta, TNFalpha, and RANKL. However, the UHMWPE-induced inflammation in RANK(-/-) mice was not associated with the osteoclastic bone resorption observed in RANK(+/+) mice. In RANK(+/+) mice subjected to UHMWPE stimulation, a large number of TRAP(+) cells were found on the implanted bone surface, where active osteoclastic bone resorption was observed. No TRAP(+) cells were found in UHMWPE-containing pouch tissues of RANK(-/-) mice. Consistent with the lack of osteoclastic activity shown by TRAP staining, no significant UHMWPE particle-induced bone resorption was found in RANK(-/-) mice. A well preserved bone collagen content (Van Gieson staining) and normal plateau surface contour [microcomputed tomography (microCT)] of implanted bone was observed in RANK(-/-) mice subjected to UHMWPE stimulation. In conclusion, this study provides the evidence that UHMWPE particles induce strong inflammatory responses, but not associated with osteoclastic bone resorption in RANK(-/-) mice. This indicates that RANK signaling is essential for UHMWPE particle-induced osteoclastic bone resorption, but does not participate in UHMWPE particle-induced inflammatory response. 相似文献
63.
谷氨酰胺在危重病患者中的应用 总被引:3,自引:0,他引:3
目的探讨危重病患者中早期经静脉应用谷氨酰胺(glutamine,Gl)的临床价值。方法42例患者随机分成两组(对照组和Gln组),Gln组进行Gln治疗(100mL/d,共7d)。治疗前后检测患者体质量、白蛋白、谷胱甘肽(GSH)、握力的变化和肠功能不全的发生率。结果体质量两组治疗前后比较差异无显著性(P〉0.05)。白蛋白、握力和GSH Gl治疗后非常显著高于治疗前(P〈0.01);白蛋白对照组治疗后较治疗前显著增高(P〈0.05),但握力和GSH治疗前后均无显著变化(P〉0.05);肠功能不全的发生率Gln组为4.8%,显著低于对照组(28.6%,P〈0.05)。结论在危重病患者疾病早期通过静脉途径外源性地补充Gln,有效改善了患者的营养状况;使患者血浆中的GSH水平增高,加强了机体的抗氧化能力;减少了患者肠功能不全的发生率。 相似文献
64.
医科院校学生心理危机管理浅探 总被引:2,自引:0,他引:2
结合医科院校学生心理危机管理的实践,阐述大学生心理危机的内涵、类型、特征及心理危机管理的特性,并从建立预警系统、增设心理委员、危机处理的专业化及危机干预策略等方面探讨在医科院校加强学生心理危机管理的对策。 相似文献
65.
66.
Harvey A. Siegal PhD ; Paul J. Draus PhD ; Robert G. Carlson PhD ; Russel S. Falck MA ; Jichuan Wang PhD 《The Journal of rural health》2006,22(2):169-173
CONTEXT: Although the nonmedical use of stimulant drugs such as cocaine and methamphetamine is increasingly common in many rural areas of the United States, little is known about the health beliefs of people who use these drugs. PURPOSE: This research describes illicit stimulant drug users' views on health and health-related concepts that may affect their utilization of health care services. METHODS: A respondent-driven sampling plan was used to recruit 249 not-in-treatment, nonmedical stimulant drug users who were residing in 3 rural counties in west central Ohio. A structured questionnaire administered by trained interviewers was used to collect information on a range of topics, including current drug use, self-reported health status, perceived need for substance abuse treatment, and beliefs about health and health services. FINDINGS: Participants reported using a wide variety of drugs nonmedically, some by injection. Alcohol and marijuana were the most commonly used drugs in the 30 days prior to the interview. Powder cocaine was used by 72.3% of the sample, crack by 68.3%, and methamphetamine by 29.7%. Fair or poor health status was reported by 41.3% of the participants. Only 20.9% of the sample felt they needed drug abuse treatment. Less than one third of the sample reported that they would feel comfortable talking to a physician about their drug use, and 65.1% said they preferred taking care of their problems without getting professional help. CONCLUSIONS: Stimulant drug users in rural Ohio are involved with a range of substances and hold health beliefs that may impede health services utilization. 相似文献
67.
目的治疗顽固性下颌磨牙根尖周炎。并尽量减少对牙周膜的机械性损伤。方法采用下牙槽神经阻滞麻醉,并配合局部麻醉。拔牙钳的尖置放于釉牙骨质界以上,采用颊舌向摆动的方式将患牙拔下。在不断滴有生理盐水的条件下,立即用高速车针磨除患牙根尖2 ̄3mm的牙体组织,根管内3 ̄5mm深的充填物要用圆钻将其清除,再用牙胶尖和氢氧化钙糊剂充填。将患牙再植入牙槽窝之前,务必用生理盐水将牙槽窝冲洗干净,要求严格控制在15分钟内完成再植,并尽量减少对牙周膜的机械性损伤。再植牙齿一般不需要夹板固定,必要时可采用缝线缝合固定。结果我们选择的5例患者,术后随访1 ̄2年,1例患者再植失败,4例患者再植成功。结论特异性再植术治疗顽固性下颌磨牙根尖周炎疗效理想,而且较易掌握。 相似文献
68.
We report clinical, neuroradiologic features, and neuropathologic findings of a 76‐year‐old man with coexistent Pick’s disease and progressive supranuclear palsy. The patient presented with loss of recent memory, abnormal behavior and change in personality at the age of 60. The symptoms were progressive. Three years later, repetitive or compulsive behavior became prominent. About 9 years after onset, he had difficulty moving and became bed‐ridden because of a fracture of his left leg. His condition gradually deteriorated and he developed mutism and became vegetative. The patient died from pneumonia 16 years after the onset of symptoms. Serial MRI scans showed progressive cortex atrophy, especially in the bilateral frontal and temporal lobes. Macroscopic inspection showed severe atrophy of the whole brain, including cerebrum, brainstem and cerebellum. Microscopic observations showed extensive superficial spongiosis and severe neuronal loss with gliosis in the second and third cortical layers in the frontal, temporal and parietal cortex. There were Pick cells and argyrophilic Pick bodies, which were tau‐ and ubiquitin‐positive in neurons of layers II–III of the above‐mentioned cortex. Numerous argyrophilic Pick bodies were observed in the hippocampus, especially in the dentate fascia. In addition, moderate to severe loss of neurons was found with gliosis and a lot of Gallyas/tau‐positive globus neurofibrillary tangles in the caudate nucleus, globus pallidus, thalamus, substantia nigra, locus coeruleus and dentate nucleus. Numerous thorned‐astrocytes and coiled bodies but no‐tuft shaped astrocytes were noted in the basal ganglion, brainstem and cerebellar white matter. In conclusion, these histopathological features were compatible with classical Pick’s disease and coexistence with progressive supranuclear palsy without tuft‐shaped astrocytes. 相似文献
69.
医改尚未成功,路在何方? 总被引:3,自引:0,他引:3
李连达 《浙江中医药大学学报》2006,30(2):125-126
目前我国医疗制度改革尚未取得成功,这与计划经济向市场经济转轨这历史时期及卫生工作的特殊性有关,出现问题,甚至失误,在所难免。提出(1)医改的目的是确保全国人民健康,人人享有医疗保健。(2)把卫生系统推向市场,医疗机构商业化,不是医改的方向。(3)预防为主,健全预防医学制系。(4)国家增加投入。(5)制定公立及私立医院各项制度,保护医务人员的合法权益。(6)加强社区基层医疗机构的建设。 相似文献
70.
A Trakic F Liu H Sanchez Lopez H Wang S Crozier 《Magnetic resonance in medicine》2007,57(6):1119-1130
The switching of magnetic field gradient coils in magnetic resonance imaging (MRI) inevitably induces transient eddy currents in conducting system components, such as the cryostat vessel. These secondary currents degrade the spatial and temporal performance of the gradient coils, and compensation methods are commonly employed to correct for these distortions. This theoretical study shows that by incorporating the eddy currents into the coil optimization process, it is possible to modify a gradient coil design so that the fields created by the coil and the eddy currents combine together to generate a spatially homogeneous gradient that follows the input pulse. Shielded and unshielded longitudinal gradient coils are used to exemplify this novel approach. To assist in the evaluation of transient eddy currents induced within a realistic cryostat vessel, a low-frequency finite-difference time-domain (FDTD) method using the total-field scattered-field (TFSF) scheme was performed. The simulations demonstrate the effectiveness of the proposed method for optimizing longitudinal gradient fields while taking into account the spatial and temporal behavior of the eddy currents. 相似文献