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81.
82.
A case of an unusual destructive hip osteoarthropathy with a plain-film record of rapid joint destruction is reported. In the absence of any laboratory or pathological support for other pathology this is thought to be an uncommon example of erosive or inflammatory osteo-arthritis in a large joint. 相似文献
83.
Recent evidence describing a suboptimal clinical outcome in women with
hydrosalpinges who undergo in-vitro fertilization (IVF) and embryo transfer
suggests a potential deleterious effect of this fluid on in- utero embryo
development. Consequently, we evaluated in-vitro mouse embryo development
in the presence of hydrosalpingeal fluid (HF) collected from 10 infertile
women of reproductive age. Chemical analyses showed both similarities and
differences of these fluids to reported values for fluids collected from
non-diseased Fallopian tubes. The HF had a significant deleterious effect
upon mouse embryo cleavage and development to the expanded and hatched
blastocyst stage, although the effect was variable among patients. Dilution
of HF to 30% concentration with culture medium failed to negate this
effect. This argues against the effect resulting from a relative lack of
critical, supportive component(s) in the HF. Additionally, further
experiments performed with cultures under an oil overlay significantly
reduced the embryotoxicity of the HF. This evidence suggests there may be a
lipophilic factor that can impair embryo development. The relatively poor
IVF-embryo transfer success in women with proximally patent hydrosalpinges
may be explained, at least in part, by reflux of a lipophilic embryotoxic
factor(s) into the uterine cavity.
相似文献
84.
Educational preferences, impediments to obtaining an education, and the needs of occupational health nurses are not well understood. The purposes of this regional study were to determine the graduate and continuing educational preferences, impediments, and needs of occupational health nurses in the states of Texas, New Mexico, Arkansas, Louisiana, and Oklahoma. Questionnaires (1,172) were mailed to all occupational health nurses identified by the respective state boards of nursing (N = 5). Results from 256 (response rate of 21.8%) returned questionnaires show 43.8% were interested in obtaining a graduate degree in occupational health nursing while only 48.8% of employers encourage them to obtain a higher degree. Only 33.2% reported the company for which they work provides rewards for obtaining an advanced degree or certification as an occupational health nurse. The two greatest impediments to obtaining a graduate degree as an occupational health nurse were a long distance from campus (56.3%) and lack of money (37.9%). 相似文献
85.
Parnell SE Ramadoss J Delp MD Ramsey MW Chen WJ West JR Cudd TA 《Experimental physiology》2007,92(5):933-943
Cerebral hypoxia has been proposed as a mechanism by which prenatal ethanol exposure causes fetal alcohol spectrum disorder (FASD) in children, but no study had tested this hypothesis using a chronic exposure model that mimicks a common human exposure pattern. Pregnant sheep were exposed to ethanol, 0.75 or 1.75 g kg(-1) (to create blood ethanol concentrations of 85 and 185 mg dl(-1), respectively), or saline 3 days per week in succession (a 'binge drinking' model) from gestational day (GD) 109 until GD 132. Fetuses were instrumented on GD 119-120 and studied on GD 132. The 1.75 g kg(-1) dose resulted in a significant increase in fetal biventricular output (measured by radiolabelled microsphere technique) and heart rate, and a reduction of mean arterial pressure and total peripheral resistance at 1 h, the end of ethanol infusion. The arterial partial pressure of CO(2) was increased, arterial pH was decreased and arterial partial pressure of O(2) did not change. Fetal whole-brain blood flow increased by 37% compared with the control group at 1 h, resulting in increased cerebral oxygen delivery. The elevation in brain blood flow was region specific, occurring preferentially in the ethanol-sensitive cerebellum, increasing by 44% compared with the control group at 1 h. There were no changes in the lower dose group. Assessment of regional differences in the teratogenic effects of ethanol by stereological cell-counting technique showed a reduced number of cerebellar Purkinje cells in response to the 1.75 g kg(-1) dose compared with the control brains. However, no such differences in neuronal numbers were observed in the hippocampus or the olfactory bulb. We conclude that repeated exposure to moderate doses of ethanol during the third trimester alters fetal cerebral vascular function and increases blood flow in brain regions that are vulnerable to ethanol in the presence of acidaemia and hypercapnia, and in the absence of hypoxia. 相似文献
86.
An apolipoprotein A-II polymorphism (-265T/C, rs5082) regulates postprandial response to a saturated fat overload in healthy men 总被引:2,自引:0,他引:2
87.
88.
Moorthy D Peter I Scott TM Parnell LD Lai CQ Crott JW Ordovás JM Selhub J Griffith J Rosenberg IH Tucker KL Troen AM 《The Journal of nutrition》2012,142(8):1554-1560
The C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene differs in frequency in various ethnic groups that have differing prevalence of age-related cognitive impairments. We used a series of neuro-psychological tests to examine the association of the MTHFR C677T polymorphism with cognition and depression and also to assess whether genotype modifies the association of folate and homocysteine with these outcomes. This study analyzed pooled cross-sectional data from 2 ethnically diverse cohorts of community-living adults: the Boston Puerto Rican Health Study (n = 939) and the Nutrition, Aging, and Memory in Elders study (n = 1017). Individuals in both cohorts underwent anthropometric and laboratory measurements and dietary and health assessments using validated questionnaires between the years 2003 and 2007. Cognitive outcomes included measures of global cognition [Mini-Mental Status Exam (MMSE)], depression (Center for Epidemiological Studies Depression Scale), and 3 factor scores for the domains of attention, executive function, and memory that were derived from a detailed set of neuropsychological tests. Low plasma vitamin B-12 concentrations were associated with poorer MMSE scores and higher depression scores, and low vitamin B-6 concentrations were associated with lower MMSE and worse attention and executive function in the multivariate analysis. In contrast, MTHFR genotype, folate, and homocysteine were not associated with cognition or depression in either ethnicity-pooled or stratified analysis. The current study did not find evidence of an association between the MTHFR C677T TT genotype and impaired cognition or depression in a population with adequate folate status and a high prevalence of cognitive impairment and depression. 相似文献
89.
Macon WR; Williams ME; Greer JP; Hammer RD; Glick AD; Collins RD; Cousar JB 《Blood》1996,87(4):1474-1483
Natural killer (NK)-like T cells are major histocompatibility complex- unrestricted cytotoxic T cells that are surface CD3-positive, express NK-cell antigens, and rearrange their T-cell receptor. Most neoplasms arising from this T-cell subpopulation have been a chronic lymphoproliferative disease referred to as T-large granular lymphocyte (LGL) leukemia. Only 10 NK-like T-cell lymphomas have been described in detail previously; this study presents the clinicopathologic features of six others and distinguishes these lymphomas from T-LGL leukemia. All patients presented with B-symptoms and often had marked hepatosplenomegaly without significant peripheral lymphadenopathy. Four of the six patients were immunosuppressed. All had CD3, CD8, CD56- positive tumors, presumably of hepatosplenic (n = 3), intestinal (n = 1), pulmonary (n = 1), or nodal (n = 1) origin. Three patients had lymphomatous bone marrow infiltrates, and four had peripheral blood involvement by neoplastic large lymphocytes, some of which had a blastic appearance or resembled virocytes. Azurophilic granules, ultrastructurally corresponding to cytoplasmic dense core and/or double density granules, were seen in all cases. T-cell clonality was shown in five tumors by Southern blot analysis, and three had abnormal karyotypes. Two untreated patients died 20 days after presentation, and three patients who received combination chemotherapy died within 5 months of presentation. One patient remains in complete remission 22 months after treatment. These findings suggest NK-like T-cell lymphomas are aggressive, are clinicopathologically distinct from T-LGL leukemia, and should be in the differential diagnosis of extranodal T-cell lymphoproliferations, including those in immunosuppressed patients. Furthermore, the LGL morphology, phenotype, and tissue distribution of some NK-like T-cell lymphomas suggest they arise from thymic- independent T cells of the hepatic sinusoids and intestinal mucosa. 相似文献
90.
Commitment of hemopoietic progenitors to the T-cell lineage is a crucial requirement for T-cell development, yet the timing and developmental cues regulating this process remain controversial. Here we have devised a technique to analyze the T-cell/B-cell lineage potential of precursors that have been recruited to the fetal mouse thymus but which have yet to contact the thymic epithelial microenvironment. We show that lymphoid progenitors arriving at the thymus are not bipotent T/B precursors, and provide evidence that intrathymic Notch signaling is not the mechanism determining T/B lineage choice in migrant precursors. Rather, we provide evidence that Notch signaling influences T/B lineage choice in lymphoid precursors through interactions with defined stromal components within the fetal liver. Collectively, our data redefine our understanding of the role and timing of Notch signaling in relation to lineage choices in lymphoid precursors. 相似文献