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81.
Membrane interlocking domains in the lens   总被引:1,自引:0,他引:1  
"Ball and socket"-like membrane processes interlock fiber cells in the sheep lens cortex, but appear reduced deeper in the lens. Wheat germ agglutinin (WGA) binds preferentially to these ball and socket structures, and more weakly to other membrane regions. On protein blots, 125I WGA binds to glycoproteins with 140,000 and 32,000 apparent molecular weight, the smaller protein also binding 125I fibronectin. In two animal cataract models, the intense WGA labeling of globular bodies replaces the spotty WGA staining pattern associated with the ball and sockets in the normal lens.  相似文献   
82.
Maternal and Child Health Journal - Each year, 3% of infants in the Unites States (US) are born with congenital anomalies, including 3000 with neural tube defects. Multivitamins (MVIs) including...  相似文献   
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84.
Obesity, a growing pandemic, is a risk factor for many cancers and causes increased bone marrow adipose tissue (BMAT). in vitro studies and obese animal models suggest that BMAT contributes to cancer progression, but there is a lack of preclinical models to directly test BMAT's role in cancer. Overactivation of peroxisome-proliferator-activated receptor-γ (PPARγ) can skew bone formation and resorption rates, resulting in increased BMAT and trabecular bone loss. Thiazolidinediones (eg, rosiglitazone) are anti-diabetic therapies that promote adipogenesis through PPARγ activation. We investigated if rosiglitazone increases BMAT in an immunocompromised model, commonly used in cancer research, and if these effects could be reversed by co-administering a bone anabolic agent (sclerostin-neutralizing antibody [Scl-Ab]), which has been shown to inhibit adipogenesis, using DXA, μCT, OsO4 μCT, and dynamic histomorphometry. Four weeks of rosiglitazone in female SCID Beige mice (cohort 1) significantly decreased trabecular bone volume (BV/TV) by about one-half, through increased osteoclast and suppressed osteoblast activity, and significantly increased BMAT. In cohort 2, mice were administered rosiglitazone ± Scl-Ab for 4 weeks, and then rosiglitazone was discontinued and Scl-Ab or vehicle were continued for 6 weeks. Scl-Ab significantly increased bone parameters (eg, BV/TV, N.Ob/B.Pm, and MS/BS) in both groups. Scl-Ab also overcame many negative effects of rosiglitazone (eg, effects on trabecular bone parameters, increased mineralization lag time [MLT], and decreased bone formation rate [BFR]). Interestingly, Scl-Ab significantly decreased rosiglitazone-induced BMAT in the femur, mostly due to a reduction in adipocyte size, but had a much weaker effect on tibial BMAT. These data suggest targeting sclerostin can prevent rosiglitazone-induced bone loss and reduce BM adiposity, in some, but not all BMAT locations. Collectively, our data demonstrate that rosiglitazone increases BMAT in SCID Beige mice, but concomitant changes in bone may confound its use to specifically determine BMAT's role in tumor models. © 2020 American Society for Bone and Mineral Research (ASBMR).  相似文献   
85.
Annals of Surgical Oncology - Breast cancer-related lymphedema (BCRL) is a source of postoperative morbidity for breast cancer survivors. Lymphatic microsurgical preventive healing approach...  相似文献   
86.
We have previously described the use of sirolimus (SRL) as primary immunosuppression following heart transplantation (HT). The advantages of this approach include attenuation of cardiac allograft vasculopathy (CAV), improvement in glomerular filtration rate (GFR), and reduced malignancy. However, in some patients SRL may cause significant proteinuria. We sought to investigate the prognostic value of proteinuria after conversion to SRL. CAV progression and adverse clinical events were studied. CAV progression was assessed by measuring the Δ change in plaque volume (PV) and plaque index (PI) per year using coronary intravascular ultrasound. Proteinuria was defined as Δ urine protein ≥300 mg/24 h at 1 year after conversion to SRL. Overall, 137 patients were analyzed (26% with proteinuria). Patients with proteinuria had significantly lower GFR (P = .005) but similar GFR during follow-up. Delta PV (P < .001) and Δ PI (P = .001) were significantly higher among patients with proteinuria after adjustment for baseline characteristics. Multivariate Cox regression analysis showed higher all-cause mortality (hazard ratio 3.8; P = .01) with proteinuria but similar risk of CAV-related events (P = .61). Our results indicate that proteinuria is a marker of baseline renal dysfunction, and that HT recipients who develop proteinuria after conversion to SRL have less attenuation of CAV progression and higher mortality risk.  相似文献   
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Objective:Using a novel mediation method that presents unbiased results even in the presence of exposure–mediator interactions, this study estimated the extent to which working conditions and health behaviors contribute to educational inequalities in self-rated health in the workforce.Methods:Respondents of the longitudinal Survey of Health, Ageing, and Retirement in Europe (SHARE) in 16 countries were selected, aged 50–64 years, in paid employment at baseline and with information on education and self-rated health (N=15 028). Education, health behaviors [including body mass index (BMI)] and working conditions were measured at baseline and self-rated health at baseline and two-year follow-up. Causal mediation analysis with inverse odds weighting was used to estimate the total effect of education on self-rated health, decomposed into a natural direct effect (NDE) and natural indirect effect (NIE).Results:Lower educated workers were more likely to perceive their health as poor than higher educated workers [relative risk (RR) 1.48, 95% confidence interval (CI) 1.37–1.60]. They were also more likely to have unfavorable working conditions and unhealthy behaviors, except for alcohol consumption. When all working conditions were included, the remaining NDE was RR 1.30 (95% CI 1.15–1.44). When BMI and health behaviors were included, the remaining NDE was RR 1.40 (95% CI 1.27–1.54). Working conditions explained 38% and health behaviors and BMI explained 16% of educational inequalities in health. Including all mediators explained 64% of educational inequalities in self-rated health.Conclusions:Working conditions and health behaviors explain over half of the educational inequalities in self-rated health. To reduce health inequalities, improving working conditions seems to be more important than introducing health promotion programs in the workforce.  相似文献   
89.
Cytochemical staining and ultrastructural characteristics of peripheral blood leucocytes from the yellow rat snake are described. A panel of cytochemical stains, including demonstration of myeloperoxidase, acid phosphatase, naphthol AS-D chloracetate esterase, alpha-naphthol butyrate esterase and alkaline phosphatase activities; and periodic acid-Schiff and Sudan Black-B staining was performed. Snake heterophils lacked peroxidase, alkaline phosphatase and acid phosphatase activity. Azurophils stained positively for all stains except alkaline phosphatase activity. Lymphocytes showed positive acid phosphatase activity. Differentiation of thrombocytes from lymphocytes was very difficult even with cytochemical staining. Only a minor staining difference was observed with periodic acid-Schiff stain. Thrombocytes exhibited coarse, dark, purple stippling usually located in the polar area of the cytoplasm, whereas lymphocyte staining varied from none to very fine, pale pink granules dispersed throughout the cytoplasm. Ultrastructural characteristics were similar to those of mammalian leucocytes with the exception that the snake basophil granules have no crystalline matrix, and heterophil granules appeared as large, elongate, membrane bound structures of varying density with no distinct core or matrix.  相似文献   
90.
The purpose of this study was to evaluate the effect of electrode placement in relation to muscle design for producing muscle torque when using neuromuscular electrical stimulation (NMES). Thirty-five healthy subjects (19 men, 16 women) participated in this study on a voluntary basis. All subjects were tested for maximum voluntary isometric contraction (MVC) of their dominant quadriceps femoris muscle while seated on an isokinetic dynamometer. NMES to subject tolerance was used while determining the effect of electrode placement (longitudinal and transverse) on the torque. Findings show that the longitudinal electrode position produces significantly more torque than the transverse position when the knee extensor muscles are electrically stimulated by the same current amplitude. Physical therapists should be aware of this technique when using NMES clinically to produce muscle torque. J Orthop Sports Phys Ther 1990;11(11):530-534.  相似文献   
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