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41.
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BackgroundSevere aortic stenosis (AoS) is considered a primary cause of syncope. However, other mechanisms may be present in these patients and accurate diagnosis can have important clinical implications. The aim of this study is to assess the different etiologies of syncope in patients with severe AoS and the impact on prognosis of attaining a certain or highly probable diagnosis for the syncope.MethodsOut of a cohort of 331 patients with AoS and syncope, 61 had severe AoS and were included in the study. Main cause of syncope and adverse cardiac events were assessed.ResultsIn 40 patients (65.6%), we reached a certain or highly probable diagnosis of the main cause of the syncope. AoS was considered the primary cause of the syncope in only 7 patients (17.5% of the patients with known etiology). Atrioventricular block (14 patients, 35.0%) and vasovagal syncope (6 patients, 15.0%) were the most frequently diagnosed causes. The presence of a known cause for syncope during the admission was not associated with a lower incidence of recurrence during follow-up (hazard ratio [HR] 0.69, 95% confidence interval [CI] 0.20-2.40). Syncope of unknown etiology was independently associated with greater mortality during 1-year follow-up (HR 5.4, 95% CI 1.3-21.6) and 3-year follow-up (HR 3.5, 95% CI 1.2-10.3).ConclusionsIn a high proportion of patients with severe AoS admitted for syncope, the valvulopathy was not the main cause of the syncope. Syncope in two-thirds of this population was caused by either bradyarrhythmia or reflex causes. Syncope of unknown cause was associated with increased short- and medium-term mortality, independently from treatment of the valve disease. An exhaustive work-up should be conducted to determine the main cause for syncope.  相似文献   
43.
Percutaneous mitral balloon valvotomy (PMV) was performed in 10 female patients with mitral stenosis; their mean age was 31 +/- 1 years. All patients underwent echophonocardiography (Echophono) before and less than 24 hours after PMV1. Cardiac catheterization and Echophono were repeated 10 and 22 months after PMV1. Eight patients with suboptimal results (defined as a post-PMV mitral valve area [MVA]/less than 1.0 cm2 and mean gradient greater than/10 mm Hg) underwent repeat PMV (PMV2) 10 months after PMV1. The Echophono data are correlated with clinical and hemodynamic changes produced by PMV1 and PMV2. MVA increased from 0.6 +/- 0.1 to 1.1 +/- 0.01 cm2 (p = 0.0009) when PMV1 was performed with a mean effective balloon dilating area (EBDA) of 5 +/- 0.19 cm2. MVA increased from 1.0 +/- 0.1 to 1.7 +/- 0.2 cm2 (p = 0.0002) when PMV2 was performed with larger EBDA (6.4 +/- 0.34 cm2). Two factors related to the learning curve account for the superior result of PMV2: (1) use of larger EBDA and (2) optimal position of the balloons parallel to the long axis of the left ventricle. PMV1 resulted in Echophono changes consistent with decreased severity of mitral stenosis: shortening of Q-S1 from 93 +/- 4 to 82 +/- 4 msec (p less than 0.05) and (Q-S1)-(S2-OS) from 1.8 +/- 0.8 to -0.9 +/- 0.6 (p less than 0.01); prolongation of S2-OS from 75 +/- 5 to 91 +/- 5 msec (p less than 0.05) and increase of EF slope from 7 +/- 1 to 17 +/- 4 mm/sec (p less than 0.05). Compared with PMV1, post PMV2 Echophono showed a further decrease in the severity of mitral stenosis: Q-S1 decreased to 78 +/- 3 msec and (Q-S1)-(S2-OS) decreased to -0.5 +/- 0.3 msec. S2-OS increased to 86 +/- 5 msec and EF slope increased to 22 +/- 4 mm/sec. The hemodynamic and Echophono changes produced by PMV1 and PMV2 persisted at the corresponding follow-up studies. There was no evidence of restenosis. Thus Echophono is a simple, low cost method helpful in the evaluation and follow-up of patients undergoing PMV.  相似文献   
44.
The information gathered here helps to explain why risk factors in the development of VAP vary from series to series. It also explains why different investigators have found opposite effects when evaluating the antibiotics. Antibiotic therapy has a bimodal effect in the development of VAP. Antibiotics protect against pneumonia development within the first days of MV, especially against types caused by endogenous flora, but they are responsible for selection of a set of resistant pathogens that are associated with significant attributable mortality, such as P aeruginosa and MRSA. These observations suggest that risk factors vary depending on the exposure to risk (ie, length of stay or MV). This variable should be considered when stratifying patients for risk factor analysis and also in the design of clinical trials for VAP prophylaxis.  相似文献   
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46.

Introduction

Interstitial lung diseases (ILD) and, in particular, idiopathic pulmonary fibrosis, may have a significant impact on patient survival. Recent studies highlight the need for palliative care (PC) in the management of ILD patients. The aim of this study was to determine the current situation of PC in patients in Spain.

Methods

A 36-question survey addressing the main aspects of PC in ILD patients was designed. The survey was sent via email to all members of the Spanish Society of Pulmonology and Thoracic Surgery. Participation was voluntary.

Results

One hundred and sixty-four participants responded to the survey. Ninety-eight percent said they were interested in PC, 46% had received specific training, and 44% reported being responsible for PC in their ILD patients. Symptom control and end-of-life stage were the most frequent reasons for referral to PC teams. Regarding end-of-life, 78% reported consensual agreement with patients on the limitation of therapeutic efforts, 35% helped prepare an end-of-life advance directive, and 22% agreed on the place of death.

Conclusion

Despite the well-known need for PC in patients with ILD and the notable interest of the survey participants in this subject, there are clear formative and organizational gaps that should be addressed to improve care in this area in ILD patients in Spain.  相似文献   
47.
Intrauterine embryonic development in the microphallid trematode Maritrema feliui is examined by means of transmission electron microscopy. Both fertilization and eggshell formation take place in the ootype. The eggshell is formed from a shell globule material derived from the vitelline cells combined with secretions of Mehlis' gland. The proximal uterus is packed with unembryonated eggs of the oligolecithal type, each composed of a fertilized oocyte and several vitelline cells, all surrounded by the shell. Intrauterine embryonic development of the egg is followed to the early stage of outer embryonic envelope formation, resulting in an embryo of ~20 blastomeres of three different types: macromeres, mesomeres and micromeres. The first equal cleavage division of the zygote produces two macromeres. The outer envelope is of cellular origin and formed by the cytoplasmic fusion of two macromeres, which become situated at opposite poles in the peripheral layer of the embryo just beneath the eggshell. Simultaneously, other blastomeres multiply and differentiate, whereas several micromeres exhibit clear signs of degeneration or apoptosis. These results show that the embryonic development of M. feliui starts in utero and represents an example of early stage ovoviviparity. A reduction in the number of blastomeres results from a continued degeneration of micromeres, which after autolysis and re-absorption, appear to represent an important source of nutritive reserves for the embryo. The embryonic development of this digenean is discussed in relation to its life cycle.  相似文献   
48.
European Journal of Clinical Microbiology & Infectious Diseases - Complicated urinary tract infection (cUTI) is a frequent cause of morbidity. In this multinational retrospective cohort study,...  相似文献   
49.
50.
The tegument of the microphallid digenean Maritrema feliui, examined by means of TEM, is described as a syncytial epithelium organised into two layers. The outer layer is an external anucleate, cytoplasmic region connected to a second region composed of nucleate perikarya (cytons) deeply embedded in the surrounding cortical parenchyma. The surface layer of the tegument is covered by a plasma membrane with many deep invaginations, which are apparently pinocytotic. This layer also bears numerous large, electron-dense spines of two types, which are intracellular and attached to the basal plasma membrane. Its cytoplasm is rich in free ribosomes, contains numerous mitochondria, disc-shaped granules frequently arranged in a rouleau, and several large, moderately electron-dense, membranous bodies. The subtegumentary perikarya and their nuclei, which are both flattened, are described in detail, as are their connections with the surface tegument. These perikarya appear to be the source of the disc-shaped granules and some of the other inclusions present in the surface layer. The main characteristics of the tegumental structure of M. feliui are commented upon in relation to the findings of previous publications and their suggested functions.  相似文献   
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