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71.
Zeitschrift für Psychodrama und Soziometrie - Der vorliegende Beitrag der Zeitschrift für Psychodrama und Soziometrie befasst sich mit der Palliative Care als Einsatzfeld für...  相似文献   
72.
Graefe's Archive for Clinical and Experimental Ophthalmology - Persisting macular holes (PMH) after surgical release of any epiretinal traction of the vitreous and adjacent membrane may rely on...  相似文献   
73.
目的:分析葡萄膜黑色素瘤的形状对视网膜结构的影响。方法:回顾性分析葡萄膜黑色素瘤患者的病理切片和临床资料,分析肿瘤形状、大小、高度-基底比值、视网膜薄变和浸润的差异。结果:本研究包括102例患者(102眼),平均年龄45.6±12.4岁。其中葡萄膜黑色素瘤76眼(75%)为梭形细胞型,6眼(6%)为上皮样细胞型,16眼(16%)为混合细胞型,其它4眼(4%)。按肿瘤部位分:睫状体黑色素瘤3眼(2.9%),睫状体和脉络膜黑色素瘤28眼(27.5%),脉络膜黑色素瘤71眼(69.6%)。视网膜组织的分析中,43眼(43%)发现视网膜变薄,86眼(84%)发现视网膜浸润。肿瘤的高度在1.2~15.6(平均8.3±3.6) mm,肿瘤基底直径为4.8~31.2(平均17.3±6.5) mm。肿瘤峰高度-基底R值为0.53±0.32。视网膜薄变组(n=43)的平均R值显着高于无视网膜薄变组(n=59)(0.69±0.31与0.42±0.27;P<0.01)。视网膜肿瘤浸润组(n=86)的平均R值比无视网膜浸润组(n=16)略高(0.56±0.33比0.41±0.25;P=0.09),但无统计学意义。结论:高R值的肿瘤与其邻近视网膜薄变有关,与视网膜内肿瘤细胞浸润相关性不大。葡萄膜黑色素瘤的切面形状和邻近视网膜组织的受累情况关系紧密。  相似文献   
74.
Weißleder  A.  Kulla  M.  Annecke  T.  Beese  A.  Lang  P.  Beinkofer  D.  Lefering  R.  Trentzsch  H.  Jost  C.  Treffer  D. 《Der Unfallchirurg》2020,123(12):944-953
Die Unfallchirurgie - Die Versorgung schwangerer Traumapatientinnen stellt das gesamte medizinische Team vor eine besondere Herausforderung. Ziel unserer Studie war es, diese Daten zu erheben und...  相似文献   
75.

Rationale, Aims and Objectives

Medical decision-making processes in primary care are influenced by defensive medical practice. This involves a high possibility for negative consequences on many levels, for example, patient's health, health care system costs and a crisis of trust in the patient−doctor relationship. Aim of this review was to identify factors of defensive medicine-based decision-making in primary care.

Methods

This scoping review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping reviews (PRISMA-ScR) guidelines and included systematic research on MEDLINE, Google Scholar and two German databases for additional grey literature. References provided further literature. Articles in English and German published from 1 January 1982 to 15 June 2022 were assessed.

Results

From 911 publications screened, 13 publications [6 qualitative studies and 7 quantitative (3 cross-sectional) studies] were included. In these, four main categories of factors influencing defensive medical practice were identified: (social) media, patients adopting a consumer attitude, health care system based working conditions and physician's tolerance for uncertainty. Pressure deriving from these four different sources is exerted on the general practitioner and may result in a defensive medical decision behaviour.

Conclusions

Four categories on influencing factors of defensive medicine could be identified. Strategies to tolerate uncertainty should be trained in under- and postgraduate training.  相似文献   
76.
Heterogeneity of B cell involvement in acute nonlymphocytic leukemia   总被引:2,自引:0,他引:2  
In order to study the pattern of B cell involvement in acute nonlymphocytic leukemia (ANLL), multiple B lymphoid cell lines were established by Epstein-Barr virus transformation of peripheral blood mononuclear cells from two patients with the disease who were heterozygous for the X chromosome-linked glucose-6-phosphate dehydrogenase (G6PD). In one patient, the progenitor cells involved by the leukemia exhibited multipotent differentiative expression, whereas in the other patient the cells showed differentiative expression restricted to the granulocytic pathway. In the patient whose abnormal clone showed multipotent expression, the ratio of B-A G6PD in B lymphoid cell lines was skewed in the direction of type B (the enzyme characteristic of the leukemia clone) and significantly different from the 1:1 ratio expected. It is, therefore, likely that the neoplastic event occurred in a stem cell common to the lymphoid series as well as to the myeloid series. In contrast, evidence for B cell involvement was not detected in the patient whose ANLL progenitor cells exhibited restricted differentiative expression. These findings underscore the heterogeneity of ANLL. Clinically and morphologically similar malignancies in these two patients originated in progenitors with different patterns of stem cell differentiative expression. This difference may reflect differences in cause and pathogenesis.  相似文献   
77.
We describe a method that permits the study of the state of cytosine methylation and of in vivo protein-DNA interactions in higher eukaryotes. This powerful technique is applicable to any gene of interest at the single-copy level. To study DNA methylation, the total uncloned genomic DNA, digested with a restriction endonuclease is subjected to a cytosine-specific hydrazine reaction and chemical cleavage. The DNA fragments of interest are linearly amplified with Taq polymerase and a sequence-specific radioactivity labeled synthetic primer. Following amplification, the DNA fragments are separated on a sequencing gel that is directly autoradiographed. To study protein-DNA interactions in vivo, we use a similar method, except that the DNA of interest is isolated from cells treated either with dimethyl sulfate or UV light. The resolution power of this technique is demonstrated by two examples, which have been studied previously by the conventional methods of genomic sequencing and "footprinting."  相似文献   
78.
Monocyte adhesion to shear stress-activated endothelium stands as an important initial step during arteriogenesis (collateral artery growth). Using multiple approaches, we tested the hypothesis that monocyte adhesion via intercellular adhesion molecule-1 (ICAM-1) and selectin interactions is essential for adaptive arteriogenesis. Forty-eight New Zealand White rabbits received either solvent, monocyte chemoattractant protein-1 (MCP-1) alone, MCP-1 plus ICAM-mab, or MCP-1 plus an IgG2a isotype control via osmotic minipumps. After 7 days, collateral conductance was evaluated: solvent 4.01 (mL/min per 100 mm Hg), MCP-1 plus ICAM-mab 8.04 (versus solvent P=NS), and MCP-1 alone 33.11 (versus solvent P<0.05). Furthermore, the right femoral arteries of ICAM-1-/-, Mac-1-/- and mice having defective selectin interactions (FT4/7-/-) as well as their corresponding controls were ligated. One week later, perfusion ratios were determined by the use of fluorescent microspheres. FT4/7-/- mice did not show any significant difference in perfusion restoration whereas ICAM-1-/- and Mac-1-/- mice had a significant reduction in arteriogenesis as compared with matching controls (FT4/7-WT 37+/-9%, FT4/7-/- 32+/-3%, P=0.31; C57BL/6J 59+/-9%, ICAM-1-/- 36+/-8%, P<0.05; Mac-1-/- 42+/-3%, P<0.05). ICAM-1/Mac-1-mediated monocyte adhesion to the endothelium of collateral arteries is an essential step for arteriogenesis, whereas this process can proceed via selectin interaction independent mechanisms. Furthermore, in vivo treatment with monoclonal antibodies against ICAM-1 totally abolishes the stimulatory effect of MCP-1 on collateral artery growth, suggesting that the mechanism of the MCP-1-induced arteriogenesis proceeds via the localization of monocytes rather than the action of the MCP-1 molecule itself.  相似文献   
79.
Summary A number of animal studies revealed an inhibition or retardation of the progression of atherosclerosis by calcium-antagonists. Encouraged by these studies, a multicenter trial on the progression of coronary artery disease (CAD) in man was initiated testing the antisclerotic effect of nifedipine against placebo in 426 patients with mild to moderate coronary disease over 3 years. All patients underwent coronary angiography before entering the trial and will be restudied after 3 years; changes of the coronary artery lumen size are quantitatively assessed by a computer-assisted system (CAAS). INTACT (International Trial on Antiatherosclerotic Coronary Therapy) is therefore the first randomized prospective study on the progression of CAD based on a quantitated anigraphic control of the coronary system.This report presents the design of this still-ongoing study as well as inclusion and exclusion criteria. The quantitative evaluation of the coronary angiograms and the mode of compliance test are described in detail. A number of baseline data as well as the preliminary results of the quantitative evaluation of the first coronary angiograms are presented.Beside the results on the effect of the calcium-antagonist nifedipine on the progression of CAD, INTACT might also supply information on the antiatherosclerotic potency of other drugs administered additionally (beta-blockers and nitrates) and of HDL-cholesterol.  相似文献   
80.

Background

The lateral cephalogram is the most common diagnostic radiograph used in clinical orthodontics. Significant cervical spine pathology can be detected on the routine lateral cephalogram. The aim of this study is to sensitize clinicians for examining the cervical area of lateral cephalogram carefully and thus record anatomical variations.

Materials and Methods

The presence and types of ponticuli posticus were investigated on 650 lateral cephalograms which were randomly selected from archived records at AECS Maaruti College of Dental Sciences & Research Centre, Bangalore

Results

The prevalence rate of Ponticulus Posticus in our study was found to be 11.1%. Though there was slight female predominance of 11.7% as compared to 10.4% in males, difference was not statistically significant.

Conclusion

Ponticulus posticus is a common anomaly in the Indian population. If any such anomaly is detected or suspected, it must be documented in the patient''s health record and specialist consultation must be sought. The lateral cephalogram must thus be considered as one of the baseline screening tool for detecting anomalies and pathology in the cervical spine region.  相似文献   
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