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41.
To study the effects of metals on starfish in field conditions, immune responses were measured in starfish from natural populations along a metal pollution gradient (long-term contamination) and in starfish that were transferred up the gradient (short-term contamination). Coelomic amoebocyte concentration (CAC) and production of reactive oxygen species (ROS) by amoebocytes were measured in two varieties of Asterias rubens occurring in the fjord: The black variety which lives only in the low salinity upper waters (22-26/1000) and the red variety which live both in the upper layer and in the deeper layer characterized by a salinity close to that of seawater (30/1000). The studied immune responses were stimulated in starfish living along the metal pollution gradient according to the contamination of these starfish by cadmium. However, the sensitivity of these responses toward metals appeared to be strongly modulated by the salinity stress. In red starfish living at 30/1000 and transferred up the contamination gradient, the immune responses were inhibited and closely followed the short-term accumulation of metals in the animal organs. Starfish transferred down the gradient did not recover normal immune responses in the short-term and appeared highly sensitive to caging stress. It is suggested that the impact of metals on the immune responses of A. rubens in field conditions occurs in three phases. Short-term inhibitory effects are exerted by a direct action of metals on the immune cells and are followed by a recovery due to the induction of protective mechanisms. Eventually, when these mechanisms are overwhelmed by a long-term contamination, indirect and durable stimulatory effects on the immune responses appear due to a global disruption of the animal physiology.  相似文献   
42.
The accumulation of Cd, Pb, Zn, and Cu in the starfish Asterias rubens was studied in a Norwegian fjord characterized by a gradient of metal pollution in the sediments, ranging from very high metal concentrations at its head to much lower levels at its opening. The concentrations of metals in starfish from natural populations along the gradient (long-term accumulation) and in starfish that were transferred up the gradient (short-term accumulation) were compared. At long-term, Cd and Pb accumulations by starfish living at normal salinity (30/1000) were related to the level of contamination of the environment while Cu and, to a lesser extent, Zn accumulations appeared strictly controlled. At short-term, Pb was accumulated steadily, Cd and Zn were accumulated transiently in the pyloric caeca (fast compartment), and Cu was not accumulated at all. Depuration experiments (transfer down the gradient) showed that Cd and Pb were efficiently eliminated from the pyloric caeca but not from the body wall (slow compartment). It is concluded that Pb is chronically accumulated, without apparent control, Cd is subjected to a regulating mechanism in the pyloric caeca which is overwhelmed over the long-term; Zn is tightly controlled in the pyloric caeca and Cu in both pyloric caeca and body wall. A distinct color variety of starfish is restricted to the low salinity (22-26/1000) superficial water layer. This variety showed a different pattern of metal accumulation over the long-term. This pattern is attributed to the particular hydrological conditions prevailing in this upper layer.  相似文献   
43.
Ontogenesis and localization expression of genes encoding for the nuclear receptors for oxysterols (lxralpha and lxrbeta) were investigated in human and mouse placenta during gestation. Both mRNAs were detectable in the placentation throughout the gestation (from 7 days postcoitum and 6th week of gestation in mouse and human, respectively) by Northern blots or RT-PCR experiments. Lxralpha showed a higher accumulation in the mouse yolk sac. In situ hybridization pointed a specific expression of lxralpha in the human amniotic membranes.  相似文献   
44.

Objectives

The purpose of this study was to analyse the endometrial cancer (EC) patterns of recurrence based on a large French multicentre database according to ESMO-ESGO-ESTRO classification.

Methods

Data of women with histologically proven EC who received primary surgical treatment between January 2001 and December 2012 were retrospectively abstracted from seven institutions with prospectively maintained databases. The endpoints were recurrence, recurrence free survival (RFS) and overall survival (OS). Time to the first EC recurrence in a specific site was evaluated by using cumulative incidence analysis (Gray's test).

Results

Data from 829 women were analysed in whom recurrences were observed in 176 (21%) with a median and mean time to recurrence of 13 and 19.5 months, respectively. High (35%) and high-intermediate risk groups (16%) were associated with higher recurrence rates compared with low (9%) and intermediate (9%) risk patients (p < 0.0001). Women with high risk EC had a higher 5-year cumulative incidence of distant recurrence (20.7%) than women with high-intermediate, intermediate and low risk EC (5.6%, 3.5%, 3.3%), (p < 0.001), respectively. Women with high risk and high-intermediate risk EC had a higher 5-year cumulative incidence of loco-regional recurrence (24.3% and 16.6%, respectively) than women with intermediate and low risk EC (6.6% and 6.5%, respectively), (p < 0.001).

Conclusions

We report specific time and site patterns of first recurrence according to the ESMO/ESGO/ESTRO classification. Sites and hazard rates for recurrence differ widely between subgroups over time. Defining patterns of EC recurrence may provide useful information for developing follow-up recommendations and designing therapeutic approaches.  相似文献   
45.
Occult cardiac injury following blunt trauma is more commonthan generally suspected. Myocardial contusion is not rare,however, it is generally a benign disorder which often remainsundiagnosed. We report a case of a right atrial rupture afterblunt chest trauma causing a tamponade. A 24-year-old man was involved in a violent car accident andhe presented in a state of collapse. A multislice computed tomographyindicated a pericardial effusion (Figure 1). A transthoracicechocardiography was performed and confirmed pericardial effusionwhich was hyperechoic (Figure 2, Movie 1). Concerns abouta possible mass in the right atrium led to examination withtransesophageal echocardiography (Figure 3, Movie 2) whichrevealed the presence of a voluminous mass in the right atrium.The patient successfully underwent cardiac surgery to removethe mass, identified as a blood clot, and to repair the atrialtear. The present case is of special interest because of therarity of documented incidents of blunt chest trauma causingright atrial tear and illustrates the usefulness of transesophagealechocardiography in completing the diagnosis in the event ofhaemopericardium.  相似文献   
46.
Endocrine tumours of the pancreas (ETPs) are rare neoplasms that are frequently malignant. Despite their usual slow growth, metastases do occur and have a major impact on prognosis. Metastases may be the first manifestation of disease, and recognition of particular radiological features of these hypervascular metastases should suggest their possible neuroendocrine origin. Although somatostatin receptor scintigraphy has changed the imaging strategy for these tumours and has become their principal imaging modality, radiological techniques are still required for precise localization of scintigraphic hot spots and monitoring of response to therapy. This pictorial review shows the typical radiological features of ETP metastases and emphasizes the role of different imaging modalities.  相似文献   
47.
48.
Archives of Women's Mental Health - Insomnia symptoms are frequent during peripartum and are considered risk factors for peripartum psychopathology. Assessing and treating insomnia and related...  相似文献   
49.
50.
This summary workshop report highlights presentations and over-arching themes from an October 2011 workshop. Discussions focused on best practices in the application of biopharmaceutics in oral drug product development and evolving bioequivalence approaches. Best practices leverage biopharmaceutic data and other drug, formulation, and patient/disease data to identify drug development challenges in yielding a successfully performing product. Quality by design and product developability paradigms were discussed. Development tools include early development strategies to identify critical absorption factors and oral absorption modeling. An ongoing theme was the desire to comprehensively and systematically assess risk of product failure via the quality target product profile and root cause and risk analysis. However, a parallel need is reduced timelines and fewer resources. Several presentations discussed applying Biopharmaceutics Classification System (BCS) and in vitro-in vivo correlations in development and in post-development and discussed both resource savings and best scientific practices. The workshop also focused on evolving bioequivalence approaches, with emphasis on highly variable products (HVDP), as well as specialized modified-release products. In USA, two bioequivalence approaches for HVDP are the reference-scaled average bioequivalence approach and the two-stage group-sequential design. An adaptive sequential design approach is also acceptable in Canada. In European Union, two approaches for HVDP are a two-stage design and an approach to widen C (max) acceptance limits. For some specialized modified-release products, FDA now requests partial area under the curve. Rationale and limitations of such metrics were discussed (e.g., zolpidem and methylphenidate). A common theme was the benefit of the scientific and regulatory community developing, validating, and harmonizing newer bioequivalence methodologies (e.g., BCS-based waivers and HVDP trial designs).  相似文献   
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