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51.
目的:观察正常软骨表面的形态结构以及短时非周期大强度运动训练对关节软骨的影响。方法:实验于2001-01/09在四川省骨科医院完成。①实验动物:10~12个月龄日本大耳白兔8只,雌雄各半,体质量(3.5±0.2)kg。②实验分组:将动物分为对照组2只,训练组6只,其中训练1,2,3周各2只。③实验干预:训练组兔在电刺激笼中进行训练,训练量为20s刺激1次,刺激时间为0.2~0.5s,动物受刺激后沿刺激笼跑跳数步并转弯。训练120min/d,每组训练60min后休息20min,训练6d/周,星期日休息,分别训练1,2,3周。对照组不放在电刺激笼中,也不进行训练。④实验评估:扫描电子显微镜下观察训练前后兔股骨和胫骨髁软骨表面形态结构的变化;MIAS99图形处理软件计算浅坑(pits)的直径和面积。结果:8只兔均进入结果分析。①正常兔膝关节软骨的表面形态结构:正常软骨表面低倍镜下显示为均匀排列的浅坑,在高倍镜下呈现一种均匀多孔状结构。②运动训练后软骨表面结构的变化:训练后浅坑形态不规则,边缘粗糙,胶原纤维增粗,孔隙不均匀增大。结论:软骨表面正常的形态结构是浅坑,短时非周期大强度训练,未引起纤维断裂和碎屑,说明不会损伤软骨表面形态结构。  相似文献   
52.
目的:扫描电镜观察正常兔膝关节表面的结构,为研究关节软骨表面结构提供正常参照。方法:实验于2001-01/09在四川省骨科医院完成。日本大耳白兔8只,10~12个月龄,雌雄各半,体质量(3.5±0.2)kg。通过扫描电镜对8只实验兔股骨髁、胫骨髁的软骨表面进行观察,其中4个髁用锐器划伤。结果:纳入日本大耳白兔8只,均进入结果分析。每个正常髁的表面都显示有大量的浅坑,有锐器划伤的髁则出现了垄沟及隆突。软骨表面在高倍镜下呈现一种均匀多孔状结构。结论:软骨表面唯一呈现的结构是浅坑,垄沟和隆突可能是标本的采集、制作过程中形成的赝象。  相似文献   
53.
Lee  KR; Cox  GG; Price  HI; Johnson  JA; Neff  JR 《Radiology》1986,158(1):255-258
Conventional arteriography and intraarterial digital subtraction arteriography (IADSA) were compared in 36 patients with primary bone or soft-tissue tumors of the extremities. The sensitivity of IADSA was at least equal to conventional arteriography for demonstrating normal or abnormal major arteries and feeding arteries, equal to or superior for depicting tumor stains or draining veins, but slightly inferior for revealing minute tumor vessels. An increase of the matrix size from 256 X 256 to 512 X 512 improved these sensitivities. IADSA with 15% diatrizoate contrast material eliminated the contrast material-induced pain in all patients. With a computer-controlled iris setting, an average of 5 minutes of procedure time and 1.7 R of radiation (0.44 mC kg) per examination could be saved. IADSA reduced the cost of an examination by an average of $67. The results indicate that IADSA was diagnostic in all instances and can replace conventional arteriography for the evaluation of extremity tumors.  相似文献   
54.
We have conducted a 9-year multicenter trial of autologous bone marrow transplantation (ABMT) for acute myeloid leukemia (AML). Remission BM was purged in vitro using monoclonal antibodies (MoAbs; PM-81, AML-2- 23) and complement targeting myeloid differentiation antigens (CD15, CD14). In 1988, the preparative regimen changed from 60 mg/kg/d cyclophosphamide x 2 and fractionated total body irradiation (TBI) total dose, 1,200 cGy (Cy/fTBI), to 4 mg/kg/d busulfan x 4 and 60 mg/kg/d Cy x 2 (Bu/Cy2). Recent analysis (October 1, 1993) shows that the Bu/Cy2 regimen along with the same MoAb purging method yields an improved outcome. Seven first complete-remission (CR) (CR1), 45 second- or third-CR (CR2/3), and 11 first-relapse (R1) patients were treated with chemotherapy and TBI or chemotherapy alone followed by ABMT with MoAb-purged BM. Median age at ABMT for those patients in CR 2/3 and R1 patients was 36 years. Twenty-nine CR 2/3 and R1 patients were conditioned with Cy/fTBI, and 27 CR2/3 and R1 patients were conditioned with Bu/CY. Using the Kaplan-Meier method, the CY/fTBI, CR2/3, and R1 patients have a 3-year disease-free survival (DFS) of 21%. On the other hand, the Bu/Cy2, CR2/3, and R1 patients have a 3-year DFS of 48%. Nineteen CR2/3 and R1 patients relapsed post-ABMT. On analysis by conditioning regimen, those treated with Cy/fTBI have a 3-year relapse rate (RR) of 58%, whereas the patients conditioned with Bu/Cy2 have a 39% 3-year RR. Long-term DFS can be achieved in about 50% of patients with advanced remissions and relapsed AML using Bu/Cy2 with MoAb-purged BM.  相似文献   
55.
113 cases of pancreatic and renal disease studied by both ultrasound and computed tomography (CT) were analyzed retrospectively. CT provided a diagnosis when pancreatic ultrasound was unsuccessful due to overlying bowel gas or obesity and when renal ultrasound was unsuccessful due to obesity, reverberations from ribs, small lesions, or multiple lesions. Conversely, ultrasound provided a diagnosis when CT was unsuccessful due to lack of fat planes or respiratory motion. CT usualy distinguished carcinoma from pancreatitis when ultrasound showed a focal echogenic mass. CT resolved renal cyst from neoplasm when ultrasound showed a mixed echo pattern mass.  相似文献   
56.
Characterization of nonlymphoid cells derived from rat peripheral lymph   总被引:23,自引:13,他引:10       下载免费PDF全文
Mesenteric lymphadenectomy in rats is followed by union of peripheral and central lymphatics, allowing the collection of intestine-derived peripheral lymph cells via the thoracic duct for several days. These cells include a proportion of nonlymphoid cells (NLC) that show irregular and heterogeneous surface morphology including long pseudopodia and veils. They stain variably for nonspecific esterase and acid phosphatase and are ATPase-positive. Their nuclei are irregular and some contain cytoplasmic inclusions, some of which show peroxidase activity and/or contain DNA. NLC have a range of densitites generally lower than that of lymphocytes. Freshly collected NLC express the leukocyte-common antigen (defined by monoclonal antibody MRC Ox 1) and Ia antigens (I-A and I-E subregion products defined by monoclonal antibodies) but they show a relative lack of other surface markers normally found on rat B or T lymphocytes (W3/13, W3/25, MRC Ox 12 (sIg), MRC Ox 19) or rat macrophages (FcR, C’R, mannose R, W3/25). In general NLC are only weakly adherent to glass or plastic. Although a subpopulation of NLC appear to have had a phagocytic past, freshly collected NLC fail to phagocytose a variety of test particles in vitro. NLC also appear incapable of pinocytosis in vitro. This heterogeneity may represent distinct subpopulations of NLC or different stages in the development of a single cell lineage. Direct cannulation of mesenteric lacteals shows that the majority of NLC are derived from the small intestine and their precursors appear to be present both in lamina propria and Peyer's patches. Kinetic studies, following irradiation or intravenous tritiated thymidine, show that the majority of NLC turn over rapidly in the intestine with a modal time of 3-5 d. Studies with bone marrow chimeras show that they are derived from a rapidly dividing precursor present in normal bone marrow. NLC occur at very low frequencies in normal thoracic duct lymph at all times following cannulation. The evidence presented suggests that NLC closely resemble mouse lymphoid dendritic cells. This conclusion is supported by evidence already obtained showing that NLC are potent stimulators of the semi-allogeneic rat primary mixed leukocyte reaction. In addition to the ceils resembling dendritic cells rare monocytoid cells are found in thoracic duct lymph of lymphadenectomized specific pathogen-free rats. The proportion of these cells increases greatly when the animals are conventionally housed. It seems probable that the physiological function of NLC is to act as accessory cells in the lymph nodes to which they normally drain. Methods for enriching NLC and thus facilitating analysis of their functions are discussed.  相似文献   
57.
58.
The immunosuppressive activity of human seminal plasma may be one factor in the aetiology of sexually transmitted disease and could be particularly important for the spread of human immunodeficiency virus (HIV). The advent of virus that can preferentially infect Langerhans cells of the genital mucosa underscores the relevance of seminal plasma effects. Virally infected cells are eradicated by the killing activity of T cells and natural killer (NK) cells and this cytotoxicity is stimulated by IL-12 (previously known as natural killer cell stimulatory factor) and partly inhibited by IL-10 (previously known as cytokine synthesis inhibitory factor). We have examined the effects of human seminal plasma on the production of these key cytokines. Cytokine production was measured in rapidly diluted, fresh, lipopolysaccharide (LPS)-stimulated, whole blood since this provided leukocytes with minimal exposure to prostaglandin. Prostaglandin concentrations and cytokine release were measured by ELISA. Addition of human seminal plasma diluted up to 100,000 times (0.001%) to blood cell cultures led to a marked increase in the IL-10/IL-12 ratio (P <0.02). A dose- dependent increase in the ratio was observed in five separate experiments, from a control value of 1 (no seminal plasma) to a mean value of 80 (1% seminal plasma). This cytokine switch was also seen when seminal plasma was substituted by pure prostaglandin E (PGE) and 19-OH PGE (the main prostaglandin constituent of human seminal plasma). Lipid-extracted seminal plasma was considerably less active at high dilutions than whole seminal plasma at the same dilution. However, its activity could be restored by the addition of synthetic PGE and 19- hydroxy PGE. A stimulation of IL-10 and a decrease in IL-12 in host- defence cells of the lower female reproductive tract will seriously affect the ability of cytotoxic T cells and NK cells to recognise and destroy virally infected cells. In addition, the stimulation of IL-10 will inhibit the release of the anti-HIV activity from CD8+ve cells. The cytokine switch reported here, activated by semen deposition, would exercise a key inhibitory control over vital immune defences in the lower genital tract, with ablation of cell-mediated responses and immunosurveillance.   相似文献   
59.

Background

The aim of this paper is to assess the mental health system in Brazil in relation to the human resources and the services available to the population.

Methods

The World Health Organization Assessment Instrument for Mental Health Systems (WHO AIMS) was recently applied in Brazil. This paper will analyse data on the following sections of the WHO-AIMS: a) mental health services; and b) human resources. In addition, two more national datasets will be used to complete the information provided by the WHO questionnaire: a) the Executive Bureau of the Department of Health (Datasus); and b) the National Register of Health Institutions (CNS).

Results

There are 6003 psychiatrists, 18,763 psychologists, 1985 social workers, 3119 nurses and 3589 occupational therapists working for the Unified Health System (SUS). At primary care level, there are 104,789 doctors, 184, 437 nurses and nurse technicians and 210,887 health agents. The number of psychiatrists is roughly 5 per 100,000 inhabitants in the Southeast region, and the Northeast region has less than 1 psychiatrist per 100,000 inhabitants. The number of psychiatric nurses is insufficient in all geographical areas, and psychologists outnumber other mental health professionals in all regions of the country. The rate of beds in psychiatric hospitals in the country is 27.17 beds per 100,000 inhabitants. The rate of patients in psychiatric hospitals is 119 per 100,000 inhabitants. The average length of stay in mental hospitals is 65.29 days. In June 2006, there were 848 Community Psychosocial Centers (CAPS) registered in Brazil, a ratio of 0.9 CAPS per 200,000 inhabitants, unequally distributed in the different geographical areas: the Northeast and the North regions having lower figures than the South and Southeast regions.

Conclusion

The country has opted for innovative services and programs, such as the expansion of Psychosocial Community Centers and the Return Home program to deinstitutionalize long-stay patients. However, services are unequally distributed across the regions of the country, and the growth of the elderly population, combined with an existing treatment gap is increasing the burden on mental health care. This gap may get even wider if funding does not increase and mental health services are not expanded in the country. There is not yet a good degree of integration between primary care and the mental health teams working at CAPS level, and it is necessary to train professionals to act as mental health planners and as managers. Research on service organization, policy and mental health systems evaluation are strongly recommended in the country. There are no firm data to show the impact of such policies in terms of community service cost-effectiveness and no tangible indicators to assess the results of these policies.  相似文献   
60.
Summary A wide variety of congenital vascular anomalies of the superior mediastinum exist. Being clinically silent, most of these anomalies are detected incidentally on plain radiographs or CT scans where they could be mistaken for mediastinal masses. Familiarity with these anomalies is very important for correct interpretation and avoidance of confusion. We present a case of a mediastinal mass detected accidentally on plain radiography which on further radiological investigation was found to be an unreported normal variant of the superior vena cava (SVC). CT scans of the thorax and superior vena cavograms showed excessive anteriorisation of the SVC in the presence of an azygos lobe. After reviewing the literature and the embryology of the SVC and azygos lobe, we postulate that the variation in the location of the SVC was possibly due to the presence of the azygos lobe.
Ventralisation excessive de la veine cave supérieure associée à un lobe azygos
Résumé Il existe une grande variété d'anomalies vasculaires congénitales du médiastin supérieur. Le plus souvent cliniquement silencieuses, ces anomalies sont alors détectées incidemment sur des radiographies ou des scanners où elles peuvent être prises pour des masses médiastinales. La connaissance de ces anomalies est très importante pour une interprétation correcte des documents et éviter toute confusion. Nous présentons le cas d'une masse médiastinale détectée fortuitement sur une radiographie qui s'avéra être, sur des investigations radiologiques complémentaires, une variation non rapportée de la v. cave supérieure (VCS). Le scanner thoracique et la phlébographie cave supérieure ont montré une ventralisation excessive de la VCS et la présence d'un lobe azygos. Après avoir relu la littérature et revu l'embryologie de la VCS et du lobe azygos, nous pensons que cette variation de l'emplacement de la VCS peut être due à la présence du lobe azygos.
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