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排序方式: 共有1111条查询结果,搜索用时 15 毫秒
1.
Abstract

Objective

Ras wild-type metastatic colorectal cancers (mCRC) may be treated with anti-vascular endothelial growth factor (VEGF) or anti-epidermal growth factor receptor (EGFR) agents. We aim to estimate patients’ preferences for mCRC treatment and relative importance of cost, efficacy improvement, avoidance of side effects and therapy convenience, and relative uptake between profiles that resemble Bevacizumab (anti-VEGF) and Cetuximab (anti-EGFR), two commonly prescribed mCRC targeted therapies.  相似文献   
2.

Context

Family caregivers constitute a critical component of the end-of-life care system with considerable cost to themselves. However, the joint association of terminally ill cancer patients' symptom distress and functional impairment with caregivers' subjective caregiving burden, quality of life (QOL), and depressive symptoms remains unknown.

Objectives/Methods

We used multivariate hierarchical linear modeling to simultaneously evaluate associations between five distinct patterns of conjoint symptom distress and functional impairment (symptom-functional states) and subjective caregiving burden, QOL, and depressive symptoms in a convenience sample of 215 family caregiver–patient dyads. Data were collected every 2 to 4 weeks over patients' last 6 months.

Results

Caregivers of patients in the worst symptom-functional states (States 3–5) reported worse subjective caregiving burden and depressive symptoms than those in the best two states, but the three outcomes did not differ between caregivers of patients in State 3 and States 4–5. Caregivers of patients in State 5 endured worse subjective caregiving burden and QOL than those in State 4. Caregivers of patients in State 4 suffered worse subjective caregiving burden and depressive symptoms but comparable QOL to those in State 2.

Conclusion

Patients' five distinct, conjoint symptom-functional states were significantly and differentially associated with their caregivers' worse subjective caregiving burden, QOL, and depressive symptoms while caring for patients over their last 6 months.  相似文献   
3.
In this case report, orthodontic intervention was used to move the gingival margin of a maxillary canine incisally by almost 9 mm to mimic a lateral incisor. Increasing the thickness of the labial plate of bone of the canine and subsequently increasing the thickness of the attached gingiva before extrusion prevented gingival recession at a later stage. In many situations, orthodontic treatment can achieve results that could not be attained by restorations and other means of cosmetic dentistry, especially when dealing with gingival margins and gingival height. A step-by-step approach to achieving these treatment objectives is described.  相似文献   
4.
Angiosarcoma of the adrenal gland   总被引:1,自引:0,他引:1  
We report the first case of primary angiosarcoma of the adrenal gland, to our knowledge. A 54-year-old man presented with chronic left upper quadrant abdominal pain, and a left adrenal mass was subsequently found on computed tomography of the abdomen. The tumor was surgically removed and a diagnosis of adrenal angiosarcoma, supported by findings of immunoperoxidase and ultrastructural studies, was made. Seven months later, recurrent tumor resulted in an en bloc resection of lateral gastric wall, tail of pancreas, left kidney, and spleen. One year after the initial surgery, the patient was free of tumor. Angiosarcoma should be added to the list of possible primary adrenal gland malignancies.  相似文献   
5.
1. The radioligand [125I]-endothelin was used to map receptors for endothelin in rat adrenal gland using in vitro autoradiography and computerized densitometry. 2. In the adrenal, a high density of binding was found in the adrenal medulla (binding affinity constant 0.18 +/- 0.11 X 10(9)M-1) and zona glomerulosa (binding affinity constant 0.18 +/- 0.07 X 10(9)M-1). Binding was low to undetectable in the zona fasciculata and zona reticularis. Unrelated peptides did not displace endothelin. 3. These results provide evidence of endothelin receptor distribution in adrenal gland and suggest that endothelin might exert multiple actions in the adrenal gland on catecholamine and aldosterone biosynthesis and secretion.  相似文献   
6.
The cellular interactions regulating the production of collagenase by a cell line derived from a spontaneously arising rat mammary carcinoma have been studied. The cell line, BC1, was grown permanently under defined serum-free conditions, so that the poorly characterized and variable effects of serum on collagenase expression were avoided. Two stable subpopulations of cells present in BC1 cultures were defined as epithelioid cells ("E-cells") and myoepithelioid cells ("M-cells"). These subpopulations differed in their morphology, pattern of growth and susceptibility to detachment from culture vessels by trypsin. Seven clones of M-cells and 7 clones of E-cells, obtained by the limiting dilution technique, were used to determine the cellular source of collagenase and the interactions which led to its expression. M-cells displayed an absolute dependence on a soluble factor produced by E-cells for their survival in vitro. The presence of both cellular types in culture was necessary for collagenase secretion to occur, E-cells being the major source of enzyme in mixed cultures. A soluble factor produced by M-cells was largely, if not completely, responsible for the induction of collagenase secretion by E-cells. Clones representative of both subpopulations were tumorigenic in syngeneic host animals. These results suggest that the phenotypic diversity which occurs within populations of neoplastic cells may give rise to subpopulations of cells which display a more aggressive phenotype in coexistence than in isolation.  相似文献   
7.
Adriamycin-induced cardiomyopathy in rabbits was produced by intravenous injections of the drug with a short therapeutic schedule (3 mg/kg body wt administered as four intermittent doses). Animals receiving selenium supplementation of Adriamycin showed preservation of the normal pattern of the heart histologic picture. The protective effect of selenium was accompanied by increased selenium levels in the plasma and the heart muscle. An eventual interaction between the antitumor effect of Adriamycin and the protective effect of selenium was ruled out by in vitro experiments using the L1210 cell line. Selenium did not abrogate the antiproliferative effect of Adriamycin when the cells were treated simultaneously with both agents. The results from this study indicate that Adriamycin-induced cardiotoxicity could be prevented by selenium if the animals were pretreated with selenium, rather than simultaneous administration of both agents. The mechanism of this effect is not entirely understood.  相似文献   
8.
The anatomy of the cardiac conduction system in normal and malformed hearts reconstructed from histological serial sections is reviewed. The sinus node and its arterial supply are located in the right superior cavoatrial junction except in hearts with left-sided juxtaposition of the atrial appendages, mirror-image, and isomeric arrangements of the atria. In the presence of normally positioned atrial and ventricular septal structures, the triangle of Koch is a useful guide to the location of the atrioventricular node and the penetrating bundle. In hearts with isolated ventricular septal defects, it is necessary to distinguish between a perimembranous defect and a muscular inlet defect. The conduction axis runs in the area of fibrous continuity at the posteroinferior edge of a perimembranous defect but in the anterosuperior rim of a muscular inlet defect. In most hearts with tetralogy of Fallot, the danger area is the region of aortic-mitral-tricuspid fibrous continuity where the axis penetrates. In hearts with atrioventricular septal defects, the lack of contiguity between atrial and ventricular septum results in a posterior displacement of the nodal triangle and coronary sinus and an elongation of the nonbranching bundle. Hearts with abnormally located atrioventricular nodes and conduction axes are mainly those with atrioventricular discordance, ambiguous atrioventricular connection in presence of left-hand pattern ventricular topology, hearts with univentricular atrioventricular connection to a morphologically left or indeterminate ventricle, and hearts with a straddling tricuspid valve. The location of the atrioventricular node is governed by the orientation of the ventricular septum and by the pattern of ventricular topology.
Resumen Se revisa la anatomía del sistema de conducción cardiaca en los corazones normales y con malformaciones a la luz de la reconstrucción a partir de cortes histológicos seriados. El nódulo sinusal y su irrigación arterial está ubicado en la unión cavoatrial derecha, excepto en corazones con yuxtaposición izquierda de las auriculillas o con alteraciones en imagen en espejo e isoméricas de las aurículas. En presencia de estructuras septales atriales y ventriculares normalmente ubicadas, el tríangulo de Koch es una guía útil para la localización del nódulo atrioventricular y la penetración del haz. En corazones con defectos septales ventriculares aislados es necesario distinguir entre un defecto perimembranoso y un defecto del tracto muscular de entrada. El haz de conducción avanza en el área de continuidad fibrosa sobre el borde posteroinferior de un defecto perimembranoso, en el filo anterosuperior de un defecto del tracto muscular de entrada. En la mayoría de los corazones con tetralogía de Fallot el área de peligro se encuentra en la región del trígono fibroso aórticomitral y tricuspídeo sobre el cual penetra el haz de conducción. En corazones con defectos septales atrioventriculares la falta de continuidad entre el septo atrial y el ventrícular resulta en un desplazamiento posterior del triángulo de Koch y del seno coronario y en una elongación del haz no ramificado. Corazones con nódulos atrioventriculares y haces de conducción anormalmente ubicados son principalmente aquellos con discordancia atrioventricular, con conexión atrioventricular ambigua en presencia de un patrón izquierdo de arquitectura ventricular, corazones con conexión atrioventricular univentricular a un ventrículo morfológicamente izquierdo o indeterminado y corazones con válvula tricuspídea cabalgante. La ubicación del nódulo atrioventricular está determinada por la orientación del septo ventricular y por el patrón de la arquitectura ventricular.

Résumé L'anatomie du système de conduction du coeur normal et du coeur siège de malformations reconstituée à partir de coupes sériées histologiques est exposée. Le sinus nodal et sa vascularisation sont situés au niveau de la partie supérieure de la jonction auriculo-ventriculaire droite sauf dans certains cas: coeur avec juxtaposition des auricules du côté gauche, image en miroir et dispositions isomères des oreillettes. Lorsque les cloisons auriculaire et ventriculaire occupent une situation normale, le triangle de Koch constitue un repère utile pour localiser le noyau auriculo-ventriculaire et le faisceau de His. En cas de défects septaux ventriculaires isolés, il est nécessaire de distinguer les défects périmembraneux et les défects musculaires. L'axe nerveux conducteur chemine dans la zone de continuité fibreuse au bord postéroinférieur du défect périmembraneux mais il chemine au bord antéro-supérieur du défect musculaire. En cas de tétralogie de Fallot, le danger se situe souvent au niveau de la zone fibreuse de continuité aortique-mitrale-tricuspide où pénètre l'axe conducteur. En cas de coeur porteur d'un défect septal auriculo-ventriculaire, le défaut de continuité entre la cloison ventriculaire et la cloison auriculaire entraîne le déplacement postérieur du triangle nodal et du sinus coronaire ainsi que l'élongation du faisceau. Les coeurs qui présentent une anomalie du siège des noyaux auriculo-ventriculaires et des nerfs conducteurs sont principalement ceux qui sont le siège d'une anomalie auriculo-ventriculaire, d'une connexion auriculo-ventriculaire ambiguë en cas d'une disposition ventriculaire de type gauche, d'une connexion auriculo-ventriculaire univentriculaire avec une morphologie ventriculaire gauche ou indeterminée, d'une valve tricuspide en fourche. Le siège du noyau auriculo-ventriculaire est fonction de l'orientation du septum ventriculaire et de l'architecture ventriculaire.


Supported by the British Heart Foundation.  相似文献   
9.
Background: The coronavirus disease 2019 (COVID-19) pandemic has increased the already high levels of stress that higher education students experience. Stress influences health behaviors, including those related to dietary behaviors, alcohol, and sleep; yet the effects of stress can be mitigated by resilience. To date, past research studying the connections between dietary behaviors, alcohol misuse, sleep, and resilience commonly investigated singular relationships between two of the constructs. The aim of the current study was to explore the relationships between these constructs in a more holistic manner using mediation and moderation analyses. Methods: Higher education students from China, Ireland, Malaysia, South Korea, Taiwan, the Netherlands, and the United States were enrolled in a cross-sectional study from April to May 2020, which was during the beginning of the COVID-19 pandemic for most participants. An online survey, using validated tools, was distributed to assess perceived stress, dietary behaviors, alcohol misuse, sleep quality and duration, and resilience. Results: 2254 students completed the study. Results indicated that sleep quality mediated the relationship between perceived stress and dietary behaviors as well as the relationship between perceived stress and alcohol misuse. Further, increased resilience reduced the strength of the relationship between perceived stress and dietary behaviors but not alcohol misuse. Conclusion: Based on these results, higher education students are likely to benefit from sleep education and resilience training, especially during stressful events.  相似文献   
10.
PURPOSE: To perform a Phase I study of SR-4554, a fluorinated 2-nitroimidazole noninvasive probe of tumor hypoxia detected by (19)F magnetic resonance spectroscopy (MRS). EXPERIMENTAL DESIGN: SR-4554 administration, on days 1 and 8, was followed by plasma sampling for pharmacokinetic studies and by three MRS studies performed over 24 h on days 8 and 9. Unlocalized MR spectra were acquired from tumor (10- or 16-cm dual resonant 1H/19F surface coil; 1.5 T Siemens Vision MR system; 2048 transients acquired over 34 min; 1.28-ms adiabatic pulse; repetition time, 1 s). Plasma drug concentrations were measured with a validated high-performance liquid chromatography method. Noncompartmental pharmacokinetic analysis was performed. RESULTS: Eight patients underwent pharmacokinetic studies, receiving doses of SR-4554 of 400-1600 mg/m(2). Peak plasma concentrations increased linearly with the SR-4554 dose (r(2) = 0.80; P = 0.0002). The plasma elimination half-life was relatively short (mean +/- SD, 3.28 +/- 0.59 h), and plasma clearance was quite rapid (mean +/- SD, 12.8 +/- 3.3 liters/h). Urinary recovery was generally high. SR-4554 was well tolerated. A single patient experienced dose-limiting toxicity (nausea and vomiting) at 1600 mg/m(2). The maximum tolerated dose was 1400 mg/m(2). SR-4554 was detected spectroscopically in tumors immediately after infusion at doses of 400-1600 mg/m(2). At the highest dose (1600 mg/m(2)), SR-4554 was detectable in tumor at 8 h, but not at 27 h. CONCLUSIONS: SR-4554 has plasma pharmacokinetic and toxicity profiles suitable for use as a hypoxia probe. It can be detected in tumors by unlocalized MRS. Additional clinical studies are warranted.  相似文献   
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