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41.
42.
AIM: To evaluate existing evidence for the association between different type of brassiere exposures and the risk of breast cancer. METHODS: Ovid Medline, CINAHL, Cochrane Data Base of Systematic Reviews, Pubmed, Scopus, Proquest, Sciencedirect, Wiley Online Library, WanFang Data, Hong Kong Index to Chinese Periodicals, China Journal Net, Chinese Medical Current Contents, Chinese Biomedical Literature Database, China Academic Journals Full-Text database, Taiwan Electronic Periodical Services and HyRead; reference lists of published studies; original research studies published in English or Chinese examining the association between type and duration of brassiere-wearing and breast cancer risk. Data were abstracted by a first reviewer and verified by a second. Study quality was rated according to predefined criteria. “Fair” or “good” quality studies were included. Results were summarised by meta-analysis whenever adequate material was available. RESULTS: Twelve case-control studies were included in the review. Meta-analysis showed brassiere wearing during sleep was associated with a two times of increased odds. CONCLUSION: The present review demonstrates insufficient evidence to establish a positive association between the duration and type of brassiere wearing and breast cancer. Further research is essential; specifically, a large-scale epidemiological study of a better design is needed to examine the association between various forms of brassiere exposure in detail and breast cancer risk, with adequate control of confounding variables.  相似文献   
43.

BACKGROUND AND PURPOSE

BAF312 is a next-generation sphingosine 1-phosphate (S1P) receptor modulator, selective for S1P1 and S1P5 receptors. S1P1 receptors are essential for lymphocyte egress from lymph nodes and a drug target in immune-mediated diseases. Here, we have characterized the immunomodulatory potential of BAF312 and the S1P receptor-mediated effects on heart rate using preclinical and human data.

EXPERIMENTAL APPROACH

BAF312 was tested in a rat experimental autoimmune encephalomyelitis (EAE) model. Electrophysiological recordings of G-protein-coupled inwardly rectifying potassium (GIRK) channels were carried out in human atrial myocytes. A Phase I multiple-dose trial studied the pharmacokinetics, pharmacodynamics and safety of BAF312 in 48 healthy subjects.

KEY RESULTS

BAF312 effectively suppressed EAE in rats by internalizing S1P1 receptors, rendering them insensitive to the egress signal from lymph nodes. In healthy volunteers, BAF312 caused preferential decreases in CD4+ T cells, Tnaïve, Tcentral memory and B cells within 4–6 h. Cell counts returned to normal ranges within a week after stopping treatment, in line with the elimination half-life of BAF312. Despite sparing S1P3 receptors (associated with bradycardia in mice), BAF312 induced rapid, transient (day 1 only) bradycardia in humans. BAF312-mediated activation of GIRK channels in human atrial myocytes can fully explain the bradycardia.

CONCLUSION AND IMPLICATIONS

This study illustrates species-specific differences in S1P receptor specificity for first-dose cardiac effects. Based on its profound but rapidly reversible inhibition of lymphocyte trafficking, BAF312 may have potential as a treatment for immune-mediated diseases.  相似文献   
44.
Castleman''s disease of the parotid gland is an extremely rare entity, with fewer than 20 cases reported in world literature so far and only 1 previous case report describing the ultrasound findings. The Doppler findings of parotid Castleman''s disease have never been described before to the best of the authors'' knowledge. This report describes the ultrasonographic and Doppler findings in a histopathologically proven case of Castleman''s disease of the left parotid gland in a young man.  相似文献   
45.

Background  

Phagocytosis of apoptotic cells by macrophages induces a suppressor phenotype. Previous data from our group suggested that this occurs via Platelet-activating factor receptor (PAF-R)-mediated pathways. In the present study, we investigated the impact of apoptotic cell inoculation or induction by a chemotherapeutic agent (dacarbazine, DTIC) on tumour growth, microenvironmental parameters and survival, and the effect of treatment with a PAF-R antagonist (WEB2170). These studies were performed in murine tumours: Ehrlich Ascitis Tumour (EAT) and B16F10 melanoma.  相似文献   
46.
47.
Summary. Background: Fibrinogen contains an alternatively spliced γ‐chain (γ′), which mainly exists as a heterodimer with the common γA‐chain (γA/γ′). Fibrinogen γ′ has been reported to inhibit thrombin and modulate fibrin structure, but the underlying mechanisms are unknown. Objective: We aimed to investigate the molecular mechanism underpinning the influence of γ′ on fibrin polymerization, structure and viscoelasticity. Methods: γA/γA and γA/γ′ fibrinogens were separated using anion exchange chromatography. Cross‐linking was controlled with purified FXIIIa and a synthetic inhibitor. Fibrin polymerization was analyzed by turbidity and gel‐point time was measured using a coagulometer. We used atomic force microscopy (AFM) to image protofibril formation while final clot structure was assessed by confocal and scanning electron microscopy. Clot viscoelasticity was measured using a magnetic microrheometer. Results: γA/γ′ fibrin formed shorter oligomers by AFM than γA/γA, which in addition gelled earlier. γA/γ′ clots displayed a non‐homogenous arrangement of thin fibers compared with the uniform arrangements of thick fibers for γA/γA clots. These differences in clot structure were not due to thrombin inhibition as demonstrated in clots made with reptilase. Non‐cross‐linked γA/γA fibrin was approximately 2.7 × stiffer than γA/γ′. Cross‐linking by FXIIIa increased the stiffness of both fibrin variants; however, the difference in stiffness increased to approximately 4.6 × (γA/γA vs. γA/γ′). Conclusions: Fibrinogen γ′ is associated with the formation of mechanically weaker, non‐uniform clots composed of thin fibers. This is caused by direct disruption of protofibril formation by γ′.  相似文献   
48.
A family is described in which the mother made anti-Rh32 as a result of pregnancy; her second liveborn child had hemolytic disease of the newborn and required an exchange transfusion. In investigating the family, it was found that the father's RN gene did not make rhi and that his second Rh gene made normal amounts of c and e but a reduced amount of f. In the two children of the couple, who inherited a normal r or Ro from their mother, the paternally derived RN encoded an amount of rhi that could be detected in direct typing tests. In the father, lack of production of rhi by RN may have represented a suppressive effect of the ce(f) gene in trans to RN or the presence of an unlinked suppressor of Rh that might also have been responsible for the reduced production of f by his r or Ro gene. The two children in this family are the first persons in whom RN has been shown to make rhi.  相似文献   
49.
Maciejewski  J; Selleri  C; Anderson  S; Young  NS 《Blood》1995,85(11):3183-3190
Activation of Fas antigen, a cell surface receptor molecule, by its ligand results in transduction of a signal for cell death. The Fas system has been implicated in target cell recognition, clonal development of immune effector cells, and termination of the cellular immune response. Fas antigen expression on lymphocytes is regulated by interferon gamma (IFN gamma) and tumor necrosis factor alpha (TNF alpha), cytokines that also have inhibitory effects on hematopoiesis. We investigated Fas antigen expression on human marrow cells and the effects of Fas activation on hematopoiesis in vitro. Freshly isolated immature hematopoietic cells, as defined by the CD34 marker, did not express Fas antigen at levels detectable by fluorescent staining. CD34+ cells, which include progenitors and stem cells, showed low levels of Fas expression in culture, even in the presence of growth factors. Stimulation by TNF alpha and IFN gamma markedly increased Fas antigen expression on CD34+ cells. Anti-Fas antibody, which mimics the action of the putative ligand, enhanced IFN gamma- and TNF alpha-mediated suppression of colony formation by bone marrow (BM) in a dose-dependent manner. This effect did not require the presence of accessory cells. Colony formation from mature (CD34+ CD38+) and immature (CD34+ CD38-) progenitor cells and long-term culture initiating cells were susceptible to the inhibitory action of anti-Fas antibody in the presence of IFN gamma and TNF alpha. Apoptosis assays performed on total BM cells and CD34+ cells showed that anti-Fas antibody induced programmed cell death of CD34+ BM cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
50.
OBJECTIVES: To obtain population-based, clinical information regarding potentially modifiable factors contributing to death during the postneonatal period (28 to 364 days), we examined all postneonatal infant deaths in four areas of the United States to determine: (1) the cause of death from clinical and autopsy data rather than vital statistics, (2) whether death occurred during initial hospitalization or after discharge, and (3) the portion of postneonatal mortality attributable to infants who left the hospital with identified high-risk medical conditions. DESIGN AND SETTING: Retrospective medical record review of all postneonatal infant deaths with birth weights greater than 500 g (total N = 386) born to mothers residing in: (1) the city of Boston (1984 and 1985, N = 55), (2) the city of St Louis and contiguous areas (1985 and 1986, N = 123), (3) San Diego County (1985, N = 112), and (4) the state of Maine (1984 and 1985, N = 96). Deaths were identified using linked birth and death vital statistics, and medical record audits of infants' and mothers' charts were performed. Causes of death were obtained from medical record review in conjunction with autopsy if performed (72%, N = 278), medical record alone (17%, N = 67), or vital statistics if no other source was available (11%, N = 41). The medical conditions at the time of discharge for each infant were reviewed and, if judged to confer an increased risk of morbidity or mortality, were classified as high risk. RESULTS: The causes of death were sudden infant death syndrome (47%, N = 181), congenital conditions (20%, N = 77), prematurity-related conditions (11%, N = 43), infections (9%, N = 34), external causes (including injuries, drownings, ingestions, and burns) (7%, N = 25), and other (6%, N = 23). In 24% of congenital and 25% to 44% of prematurity-related deaths, infection was the acute or associated cause of death. Infants born to black mothers were more likely than those born to white mothers to die during the postneonatal period of all major causes of death (7.3 per 1000 vs 3.0 per 1000). Overall, 18% (N = 68) of deaths occurred to infants who never left the hospital; 79% (N = 305) of the infants were discharged before death; and discharge status was unknown in 3% (N = 13). Eighty-one percent of all infants with prematurity-related postneonatal deaths were never discharged, and of the total infants who were initially discharged, only 1% (N = 4) subsequently died of prematurity-related causes. Of all postneonatal deaths, only 16% (N = 62) left the hospital with identified high-risk medical conditions. CONCLUSIONS: These findings suggest that the etiology of postneonatal mortality is heterogeneous, with significant complexity in attributing specific causes of death and making designations of "preventability." The vast majority of infants who died of prematurity-related postneonatal causes never left the hospital, and only a small percentage of all infants that left the hospital before death were identified as being at high medical risk. Therefore, strategies for further decreasing postneonatal mortality must link high-risk follow-up programs to more comprehensive strategies that address risk throughout pregnancy and early childhood.  相似文献   
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