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41.
Hypercholesteremia is one of the risk factors for coronary artery disease. The present study highlights the efficacy of Ayurvedic herbal formulation Triphala (Terminalia chebula, Terminalia belerica, and Emblica officinalis) on total cholesterol, Low density lipoprotein (LDL), Very low density lipoprotein (VLDL), High density lipoprotein (HDL) and free fatty acid in experimentally induced hypercholesteremic rats. Four groups of rats were employed namely control, Triphala treated, hypercholesterolemia rats (4% Cholesterol + 1% cholic acid + egg yolk) and Triphala pre-treatment in hypercholesteremic rats. Results showed significant increase in the total cholesterol, LDL, VLDL, and free fatty acid in hypercholesteremic rats were significantly reduced in Triphala treated hypercholesteremic rats. The data demonstrated that Triphala formulation was associated with hypolipidemic effects on the experimentally induced hypercholesteremic rats.  相似文献   
42.
Purpose:The aim of this study was to measure blur thresholds before and after refractive surgery.Methods:In this prospective cohort study conducted in a tertiary eye hospital in South India. Blur thresholds were measured for 30 young adult myopic patients 1 month prior to and after refractive surgery. Patients were asked to report three stages of blur, namely Detectable Blur (DB), Bothersome Blur (BB), and Non-resolvable Blur (NB). Blur was created by adding plus lenses (in steps of 0.12D) over their optimal subjective refraction. The blur judgments were made both monocularly and binocularly when looking through a 3 mm artificial pupil at one line above the best-corrected visual acuity.Results:A total of 30 participants were included in this study (mean age = 25.5 ± 3.8 (20–36) years; 77% female). The mean binocular preoperative blur of this group was: DB = 0.39 ± 0.26D, BB = 0.74 ± 0.28D and NB = 1.04 ± 0.42D. The corresponding mean binocular blur one-month post-operatively was DB = 0.46 ± 0.28D, BB = 0.83 ± 0.35D, and NB = 1.21 ± 0.44D. Although there was a marginal increase in the blur thresholds postoperatively, the difference was not statistically significant (DB: P = 0.320; BB: P = 0.229; NB: P = 0.054).Conclusion:All three blur thresholds showed an insignificant minimal increase at 1 month post-operatively suggesting that patients adapt to the induced blur following refractive surgery. A longer follow up would reveal how the adaptation to blur would change with time.  相似文献   
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Objective: To determine whether anionic ligands for the macrophage scavenger receptor inhibit the fertilization of mouse oocytes by mouse spermatozoa.

Design: In vitro study of sperm binding and two-cell embryo formation in the presence of scavenger receptor ligands. Sperm-oocyte interaction may be mediated by sulfated sugars. In this study, we tested other nonsulfated anionic ligands for the scavenger receptor for their ability to affect fertilization. The only common feature of these ligands is their anionic nature.

Setting: Oocytes and sperm from mice were used.

Main Outcome Measure(s): Binding of sperm to oocytes and subsequent formation of two cell embryos were determined.

Result(s): Fucoidin, polyinosinic acid, oxidized low-density lipoprotein, acetyl low-density lipoprotein, and malondialdehyde-modified LDL inhibited the binding and fertilization of mouse sperm to mouse oocytes. Addition of fresh sperm to oocytes previously treated with sperm in the presence of these agents restored the binding and fertilization.

Conclusion(s): These results show that charge-based interactions analogous to the interactions of the scavenger receptor with its ligands may play an important role in mammalian fertilization.  相似文献   

45.
To reduce the number of apheresis procedures and maintain the usual rate of hematopoietic recovery in patients treated with high-dose chemotherapy, we studied the effect of adding a small volume of ex vivo expanded bone marrow to low doses of CD34(+) blood stem cells. Thirty-four patients with breast cancer received G-CSF (10 microg/kg/day) priming followed by a limited volume (50-100 ml) bone marrow aspiration and standard 10-liter aphereses. Marrow was expanded ex vivo using the AastromReplicell system and infused along with low doses of blood-derived CD34(+) cells, collected in one apheresis. Thirty-one evaluable patients received a median CD34(+) blood stem cell dose of 0.7 x 10(6)/kg (range, 0.2-2.5) and 4.7 x 10(7) nucleated cells/kg (range, 1.98-8.7) of ex vivo expanded marrow. All patients recovered with normal blood counts and engrafted 500 neutrophils/microl and 20 000 platelets/microl in a median of 10 and 13 days, respectively. Multivariate analysis revealed that, in addition to CD34(+) lineage negative cell quantity, the quantity of stromal progenitors contained in the ex vivo expanded product correlated with engraftment outcome (r = 0.551, P = 0.004). Our results indicate that ex vivo expanded bone marrow is capable of facilitating engraftment when combined with low doses of mobilized blood derived CD34(+) cells.  相似文献   
46.
BACKGROUND: Our understanding of the effect of the Accreditation Council for Graduate Medical Education (ACGME)-mandated work-hour limitation on physicians' quality of life, sleepiness, and sleep-work habits is evolving. In this study, we sought to determine the effect of work-hour reduction on quality of life in residents and fellows (ICU housestaff) when subject to the ACGME-compliant schedule of one institution. To determine the effect of work-hour reduction on subjective and objective measures of sleepiness in ICU housestaff at a center. METHODS: A single-center study of 34 residents and 10 fellows who were studied before and after the ACGME-mandated work-hour limitation went into effect in July 2003. RESULTS: In a single center, after the work-hour reduction, residents reported statistically significant but minor improvements in sleep time, subjective sleepiness, and some aspects of quality of life (p < 0.05). Both before and after work-hour limitations, subjective sleepiness and quality-of-life indexes deteriorated during the course of the ICU rotation. Following work-hour reductions, subjective sleepiness improved (p < 0.05), but objective sleepiness was unchanged (p = 0.6). Moreover, after the implementation of work-hour reductions, 59%, 43%, and 25% of the ICU team had mean sleep latency < 10, 7, and 5 min, respectively, with 14% of the team manifesting sleep-onset rapid eye movement periods (signifying severe sleepiness) before beginning their extended work-hour period. CONCLUSIONS: In ICU housestaff, at a single center, small benefits to quality of life and subjective sleepiness were realized by an ACGME-compliant work-hour schedule. Significant levels of objective sleepiness, however, remained. Further measures may need to be undertaken to address the persistence of sleepiness in ICU housestaff. These findings may not be generalized outside of the scheduling system studied.  相似文献   
47.
The adverse effects of glucocorticoid deficiency on the expression of genes encoding Leydig cell surface receptors and the response to LH/prolactin/insulin to produce testosterone production are yet to be recognized. Following metyrapone-induced corticosterone deficiency, serum corticosterone, testosterone and insulin levels decrease, whereas serum prolactin exhibits a significant increase and serum LH remains unaltered. LH binding and LH receptor mRNA expression were not altered, but a significant decrease in PRL and insulin binding and in the mRNA expressions of their receptors were observed in corticosterone-deficient rats in vivo. Corticosterone deficiency significantly decreases the Leydig cellular basal as well as hormone-stimulated testosterone production in vitro. Simultaneous administration of corticosterone prevented its deficiency-induced changes in Leydig cells both in vivo and in vitro. Our results show that metyrapone-induced corticosterone deficiency impairs Leydig cell insulin and prolactin receptors, and their mRNA expression and the response of Leydig cells to LH/PRL/insulin on testosterone production.  相似文献   
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49.
We report the crystal structures of the copper and nickel complexes of RNase A. The overall topology of these two complexes is similar to that of other RNase A structures. However, there are significant differences in the mode of binding of copper and nickel. There are two copper ions per molecule of the protein, but there is only one nickel ion per molecule of the protein. Significant changes occur in the interprotein interactions as a result of differences in the coordinating groups at the common binding site around His-105. Consequently, the copper- and nickel-ion-bound dimers of RNase A act as nucleation sites for generating different crystal lattices for the two complexes. A second copper ion is present at an active site residue His-119 for which all the ligands are from one molecule of the protein. At this second site, His-119 adopts an inactive conformation (B) induced by the copper. We have identified a novel copper binding motif involving the α-amino group and the N-terminal residues.  相似文献   
50.
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