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排序方式: 共有461条查询结果,搜索用时 17 毫秒
1.
B Jouve F Collet R Cointe P Barragan P Bru M Metge A Vaillant A Elkouby C Malmejac R Gérard 《Archives des maladies du coeur et des vaisseaux》1989,82(3):337-343
Between 1977 and 1987, 27 consecutive patients (16 men, 11 women, mean age 66 years, range 54 to 75 years) with ventricular septal rupture complicating acute myocardial infarction underwent surgical repair. The purpose of this retrospective study was to analyse the post-operative mortality factors from clinical, haemodynamic and operative data in all patients and also from coronary angiographic data in 23/27 patients whose haemodynamic status allowed this type of exploration. Seventeen patients (63 p. 100) died during the first post-operative month, 10 survived and were discharged. Factors that influenced the prognosis were: (1) inferiorly-located necrosis associated with a 75 p. 100 mortality rate (9 out of 12 patients), as opposed to 53 p. 100 (8 out of 15 patients) with anterior necrosis; (2) right ventricular dysfunction, observed in 83 p. 100 of patients with inferior necrosis and 53 p. 100 with anterior necrosis, which was responsible for 7 out of 9 deaths in the inferior necrosis subgroup and contributed to 3 out of 8 deaths in the anterior necrosis subgroup; this established a cause-effect relationship between right ventricular function and the overmortality of patients with inferior necrosis; (3) independently of the haemodynamic status, two- and three-vessel lesions (56 p. 100 of all lesions) which had an 84 p. 100 mortality rate as opposed to 40 p. 100 with one-vessel lesions; (4) the presence of a state of shock which was associated with a 78 p. 100 mortality rate as opposed to 55 p. 100 in patients without shock. We conclude that when permitted by the patient's haemodynamic status coronary angiography should be part of the pre-operative evaluation to assess the operative risk and guide the surgical procedure. 相似文献
2.
Floriana S Luppino Edward Grooters Francisca T de Bru?ne Aeilko H Zwinderman Andel G L van der Mey 《Otology & neurotology》2006,27(7):962-968
OBJECTIVE: Conservative treatment in vestibular schwannomas is mainly dependent on optimal tumor size determination. The first objective of this study was to establish interobserver and intraobserver variability and the accuracy and reproducibility of three different measurement methods: one bidimensional and two volumetrical. The second objective was to evaluate the influence of the use of different magnetic resonance imaging (MRI) slice thickness and the influence of patient's repositioning on the measurements' outcome. STUDY DESIGN: Two consecutive studies have been prospectively performed, both mainly concerning volumetrical measurements. SETTING: Both studies were performed in a tertiary academic, multidisciplinary center. PATIENTS: In the first study, 19 patients were included between March 1996 and May 2002, with a total of 52 scans. The second study comprised 14 patients. All patients in the first study had at least two MRI examinations performed according to a standard protocol (T1-weighted gadolinium-enhanced, slice thickness of 3 mm, and interslice gap of 0.3 mm). The population in the second study underwent a conservative wait and scan (W&S) treatment. METHODS: Both studies are discussed separately. In the first study, all scans were measured by four investigators, two of whom performed the measurements twice using three different methods. The first method concerns a manually performed bidimensional surface measurement along the petrous pyramid. The second method concerns a semiautomatic volumetrical measurement on a computer, relying on contour detection, and the last method concerns a fully automatic volume reconstruction also performed on a computer using different gray shade scales.All 14 patients included in the second study underwent three magnetic examinations. Three different T1-weighted gadolinium-enhanced sequences were used: the first using a slice thickness of 1 mm, the second again with 1-mm slice thickness but after having repositioned the patient. In the third sequence, a slice thickness of 3 mm was used. All scans were measured by two investigators using the three different methods, as described previously. RESULTS: The manual surface method shows large intraobserver variability, and its reproducibility is significantly lower compared with volume measurements. Because of a relatively large systematic error in small tumors, sensitivity of growth detection is low. Both volumetrical methods are hardly interobserver- and intraobserver-dependent, and the gray shade method turned out to be the most accurate. Radiologic progression is only significant at a volume increase of at least 50%. The influence of patient repositioning is negligible, whereas the use of 1-mm slice thickness seems to be superior to a 3-mm slice thickness. CONCLUSION: The volumetrical gray shade method is the most accurate method to detect early tumor progression. As tumor increase of at least 50% is needed to be able to speak of statistically significant tumor growth, the absence of radiologic progression does not mean that there is no tumor growth. Repositioning of the patient has no influence on the measurements' outcome, whereas for optimal magnetic resonance imaging examinations, a 1-mm slice thickness protocol seems to be superior. 相似文献
3.
4.
The major benefit of antenatal ultrasonography is to allow early diagnosis of urinary tract malformations before postnatal infection worsens the prognosis. In the majority of cases, there is a unilateral and moderate dilatation requiring a check-up only during the second week of life; treatment subsequently depends on the etiology of the uropathy and the consequences on the kidney. Unilateral severe dilatations and bilateral, but moderate, dilatations must be managed immediately after birth in a pediatric surgical center. In the rare cases of severe bilateral obstructive uropathy, in utero decompression by catheterisation or surgery is now considered to be uselessly invasive, considering that renal dysplasia is already present when the malformation is detected. 相似文献
5.
Model systems to study the parameters determining the success of phage antibody selections on complex antigens 总被引:4,自引:0,他引:4
Mutuberria R Hoogenboom HR van der Linden E de Bruïne AP Roovers RC 《Journal of immunological methods》1999,231(1-2):65-81
Phage antibody display technology offers a powerful tool for the isolation of specific antibodies to defined target antigens. Most selection strategies described to date have relied on the availability of purified and often recombinant antigen, providing the possibility to perform selections on a well-defined antigen source. However, when the target antigen cannot be purified (e.g., an integral membrane protein), or if the antigen is unknown (e.g., when searching for novel markers on cells or tissues), panning of phage antibody libraries has to be performed on complex antigen sources such as cell surfaces or tissue sections, or even by in vivo selection methods. This provides a series of technical and experimental challenges. One focus of our research is to select antibodies directed to novel cancer-induced antigens expressed by tumours and by the tumour vasculature. To understand the parameters governing selection on complex antigen sources and to assess the efficiency of these phage library selections, we have set up two model selection systems in which both tumour cells and vascular endothelial cells serve as target "antigen". We describe a model based on phage antibodies directed to the tumour antigen epithelial glycoprotein-2, to compare phage antibody selections on a range of different antigen sources including purified and recombinant antigen, whole live cells, tissue cryosections and in vivo grown solid tumours. Secondly, we describe a model based on a phage antibody directed against the endothelial cell inducible adhesion molecule E-selectin. We compare selections on cultured cell monolayers with selections on cell suspensions immobilised on columns, to determine which selection approach is most suitable for the identification of novel tumour endothelial cell markers. Our data provide insight into the efficiency and thus potency of different selection strategies and show that there are very large differences in the recovery and enrichment of binding phage between the different methods tested. Our results further demonstrate the feasibility of phage antibody selections on whole, intact cells and show that these may sometimes compare favourably to selections on purified antigen. Selections on endothelial cells immobilised on columns compare favourably with selections on cell-monolayers; the most favourable conditions for both selection procedures are described. The implications of our data for phage antibody selections on these different complex antigen sources using either non-immune or immune phage antibody repertoires are discussed. The use of model systems such as the ones described here will help to determine optimal experimental conditions for phage library selections on complex antigens and aid in developing more powerful selection procedures for target discovery. 相似文献
6.
Spermiogenesis of the proteocephalidean cestode Proteocephalus torulosus (Batsch, 1786) was examined for the first time using transmission electron microscopy. Spermiogenesis begins with the formation of a distal cytoplasmic protrusion, a differentiation zone, at the periphery of the early spermatid. This differentiation zone is lined with cortical microtubules and contains two centrioles aligned along the same axis. Subsequently, each centriole is associated with the striated root and the intercentriolar body appears between them. A flagellar bud arises from each centriole, growing later as a free flagellum. Simultaneously, a median cytoplasmic process (MCP) develops distally to the flagella. The two flagella, which are of unequal length, become longer and rotate towards the MCP. At this stage, two arching membranes appear at the base of the differentiation zone. The nucleus elongates and when both flagella are fused with the MCP, the nucleus subsequently migrates into the MCP. Finally, the advanced spermatids detach from a condensing residual cytoplasm at the level of the arching membranes. 相似文献
7.
The effect of yoghurt on the cytotoxic and phagocytic activity of macrophages in tumour‐bearing mice
Juan Carlos Valdez Mirta Rachid Elena Bru Gabriela Perdigón 《Food and Agricultural Immunology》1997,9(4):299-308
In a previous paper, it was demonstrated that feeding yoghurt was able to inhibit the growth of an intestinal tumour induced chemically with 1,2‐dimethylhydrazine (DMH). This effect was due to the increase in IgA‐producing cells and a diminution of the inflammatory immune response. In this paper the phagocytic and cytotoxic capacity of macrophages both involved and not involved in the target organ are studied. The study was aimed at determining whether in the intestinal tumour inhibition demonstrated previously the systemic immune response was also increased. The cytotoxic capacity and ß‐glucuronidase enzyme levels of the peritoneal macrophages were analyzed together with the cytolytic effect of the serum on tumour cells and the phagocytic activity of the macrophages infiltrating the intestinal mucosa. Groups of mice were split into three experimental groups. One group was treated with DMH. The others were treated with DMH, and their diets were supplemented with yoghurt for 7 or 10 consecutive days, during 24 weeks. It was demonstrated that feeding yoghurt for 7 or 10 days increased cytotoxic and ß‐glucuronidase levels in peritoneal macrophages, and also the cytolytic capacity of serum, reaching values significantly higher than those in the DMH control. Enhancement of the phagocytic activity of the macrophages associated with the large intestine was also observed. This increase in the macrophage activity involved in the systemic and mucosal immune responses could also be responsible for the tumour inhibition observed in the group of mice fed with yoghurt. The presence in the serum of lytic factors (cytokines) which were released by immune cells activated by feeding yoghurt may also have had a role in tumour inhibition. 相似文献
8.
B Lebeau R Grillot M Michallet A Goullier-Fleuret B Corront J P Bru 《Annales de biologie clinique》1987,45(5):582-587
This study took place between February 1984 and February 1985 in 76 febrile neutropenic patients. We evaluated the whole mycological and serological results, in 91 febrile episodes. We separated two groups: group I (acute leukemia, chronic myelo?d leukemia, medullar aplasia, lymphomas) and group II (chronic lympho?d leukemia, Hodgkin disease, myelomas, solid tumors). Patients were included in this study if they developed a temperature of 38.5 degrees C or greater and if they had less than five hundred neutrophils per mm3. They were treated with mono or bi-antibiotherapy. If the patient remained febrile more than 72 hours, an antifungal therapy was added (Amphotericin B IV). Through these weekly results, we conclude: the high frequency of digestive tract candidiasis in such patients; disseminated candidiasis occurs only in the first group patients with fungal digestive colonization; the overall response rate in this study was 77 per cent. This underlines the interest of empiric treatment with amphotericin B IV. 相似文献
9.
The fine structure of the mature spermatozoon of the pseudophyllidean tapeworm Eubothrium crassum, a parasite of salmonid fishes, has been studied by transmission electron microscopy for the first time. The mature spermatozoon of E. crassum is filiform and tapered at both extremities. It contains two axonemes of unequal length showing the 9 + "1" pattern of Trepaxonemata. The anterior extremity exhibits a crested body 50-100 nm thick. It spirals around the outside of the anterior region of the spermatozoon. The nucleus is electron-dense, exhibiting a fibrous appearance in its middle (the broadest) region. The cortical microtubules are of two types and are situated parallel to the spermatozoon axis. The cytoplasm is slightly electron-dense and contains numerous electron-dense granules in region II of the spermatozoon. A ring of electron-dense, centred microtubules surrounds the axoneme, together with the underlying ring of moderately electron-dense, subjacent submicrotubular material in region V. The anterior and posterior extremities of the spermatozoon lack cortical microtubules and contain a single axoneme. Our results reveal several peculiarities, in which the spermatozoon of E. crassum differs from those of other pseudophyllidean cestodes. 相似文献
10.
It is not easy to evaluate the prognosis of mitral valve prolapse. First of all, a positive diagnosis is difficult: the clinical insufficiencies are ill-compensated by sonocardiography as it is less reliable than expected; the very existence of the "mitral valve prolapse" described by Barlow is being challenged. Secondly, the most severe complications of mitral prolapse are rare, with respect to its frequency. Some complications are currently well defined. Thus, severe mitral insufficiency, leading to valve replacement, affects elderly men more than young women, although the pathological lesions correspond to the same disease. Endocarditis is rare and only occurs when there is an audible murmur. Rhythm disorders are varied, with however, frequent junction tachycardias and a marked influence of catecholamines, which may explain the clinical effectiveness of beta-blockers. Unfortunately, severe complications are not as well known. Thus, the risk of sudden death and cerebral vascular accident cannot be figured out from large statistical studies. Only studies of some so called "risk" sub-groups, should allow a better knowledge of these two complications and a more effective prevention. 相似文献