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1.
BACKGROUND: Optical penalization (OP) has previously been shown to successfully maintain vision in amblyopic eyes of older children when patching compliance is poor and when vision decreases once patching is discontinued. This study shows that the final vision in optically penalized eyes is often better than the vision obtained after patching alone. SUBJECTS AND METHODS: During the 5-year period from January 1992 to February 1997, 28 children aged between 3.7 and 8.2 years (average age, 6.5+/-1.1 years) were optically penalized for an average of 1.5+/-0.75 years. The maximum length of penalization was 3.3 years, whereas the minimum time was 6 months. There were 21 children with strabismic amblyopia and 7 children with anisometropic amblyopia. All 28 children had worn a patch to achieve their best visual levels and then had shown a loss of best vision when occlusion was stopped. Patching was usually resumed and continued until the previous best vision was obtained; at this point OP was started to "maintain" vision. Eighteen of the 28 children have discontinued penalization and have been followed up an average of 1(1/2) years. RESULTS: Twenty-six (93%) of the 28 patients showed an increase in best vision from that found at the conclusion of patching, and 2 patients maintained their vision at the initial level. The average visual acuity at the start of penalization was 20/50 (0.42+/-0.11 logarithm of the minimum angle of resolution [log MAR]). Final average visual acuity was 20/27 (0.15+/-0.12 log MAR). The average increase in vision was nearly 3 lines or 0.27+/-0.12 log MAR. CONCLUSION: OP alone (without the use of pharmacologic agents such as atropine) not only maintains vision after patching therapy, but also appears to improve the final visual outcome.  相似文献   
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目的:筛选一株优良的抗生素产生菌。方法:通过人为诱变来动摇产生菌原有的严密控制机制。结果:得到一种抗生素生物合成能力异常的突变株。结论:此方法可过量合成人们所期望的抗生素。  相似文献   
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目的:考察盐酸特拉唑嗪胶囊的稳定性。方法:通过影响因素(强光照射、高温、高温),加速和留样考察实验,以含量为测定指标,考察胶囊的含量变化。结果:在温度40℃、60℃、光照3500LX及RH75%等因素影响下,胶囊的含量无明显变化。结论:在25℃时,通过经典恒温加速试验推测盐酸特拉唑嗪胶囊的失效期为2年。  相似文献   
4.
BackgroundOver the years, there has been research on the anti-obesity effect of the Allium cepa bulb, but a dearth of research was carried out on the leaves, which is consumed as vegetable salad and soup, hence this study was proposed.ObjectiveThis study aims at investigating the effect of A. cepa leaves on high fat diet (HFD) induced obesity in male Wistar rats.MethodsTwenty-eight male Wistar rats were divided into four groups with seven rats each. Apart from Group 1 (normal control which received normal pelleted diet), obesity was induced in 21 rats of Group 2 to 4 with HFD. Group 2, the obese control was administered with 100% HFD, while the diet for group 3 and 4 was supplemented with 10% and 20% A. cepa powdered leaves, respectively, for 28 days.ResultsIn the rats treated with 10% and 20% A. cepa, body weight, fat mass, blood glucose, total cholesterol, triglycerides, aspartate amino transferase, alanine amino transferase, creatinine and urea levels were reduced significantly (P < 0.05) in comparison with the obese control group. The liver of the rats treated with 10% and 20% A. cepa leaves revealed small and few amounts of fat deposits in comparison with the obese control group, which revealed numerous and large deposits of fat. The kidney of the rats treated with 10% and 20% A. cepa leaves showed moderate and mild inflammation, respectively, in comparison with the obese control group which showed acute inflammation. The leaves of A. cepa had antioxidant properties and the presence of volatile compounds with anti-obesity properties in A. cepa were identified using gas chromatography-mass spectrometry (GC-MS).ConclusionA. cepa leaves had weight-loss effect in that it decreased body weight, fat mass, glucose and lipid levels including fat deposits in the liver.  相似文献   
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Schwann cells are glial cells of peripheral nervous system, responsible for axonal myelination and ensheathing, as well as tissue repair following a peripheral nervous system injury. They are one of several cell types that are widely studied and most commonly used for cell transplantation to treat spinal cord injury, due to their intrinsic characteristics including the ability to secrete a variety of neurotrophic factors. This mini review summarizes the recent findings of endogenous Schwann cells after spinal cord injury and discusses their role in tissue repair and axonal regeneration. After spinal cord injury, numerous endogenous Schwann cells migrate into the lesion site from the nerve roots, involving in the construction of newly formed repaired tissue and axonal myelination. These invading Schwann cells also can move a long distance away from the injury site both rostrally and caudally. In addition, Schwann cells can be induced to migrate by minimal insults (such as scar ablation) within the spinal cord and integrate with astrocytes under certain circumstances. More importantly, the host Schwann cells can be induced to migrate into spinal cord by transplantation of different cell types, such as exogenous Schwann cells, olfactory ensheathing cells, and bone marrow-derived stromal stem cells. Migration of endogenous Schwann cells following spinal cord injury is a common natural phenomenon found both in animal and human, and the myelination by Schwann cells has been examined effective in signal conduction electrophysiologically. Therefore, if the inherent properties of endogenous Schwann cells could be developed and utilized, it would offer a new avenue for the restoration of injured spinal cord.  相似文献   
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目的:检测维甲酸(Retinoic acid,RA)诱导小鼠胚胎腭裂模型中胎鼠舌体发育过程中肌相关 microRNAs(MyomiRs)、成肌调节因子(Myogenic regulatory factors,MRFs)以及 Pax 基因的表达变化,探究 MyomiRs 在舌肌分化过程中的调控作用,推测RA 致胎鼠腭裂伴发舌异常的可能机制。方法:建立 RA 诱导小鼠胚胎腭裂模型,分别在 E13.5、E14.5、E15.5收集胎鼠舌体组织,用 SYBR GreenⅠ实时定量 PCR 检测舌体中 MRFs 和 Pax 基因的表达;用 TaqMan 探针实时定量 PCR 检测舌体中 MyomiRs 的表达。结果:胎鼠舌体发育过程中,正常组 miR-1和 miR-206相对表达量均持续上升,RA 诱导组二者变化趋势与正常组相似,但相对表达量均低于正常组,miR-1的结果在 E14.5和 E15.5具有统计学意义(P <0.01),miR-206的结果在 E13.5具有统计学意义(P <0.05)。正常组和 RA 诱导组胎鼠舌体中 MyoD 和 Myf5相对表达量都在 E14.5达到峰值,随后下降。RA 诱导组 MyoD 的表达在 E14.5显著低于正常组(P <0.05),在 E15.5显著高于正常组(P <0.01);RA 诱导组 Myf5的表达在 E15.5显著低于正常组(P <0.05)。正常组和 RA 诱导组胎鼠舌体中 Pax3表达均在 E14.5达到峰值,Pax7表达均在 E15.5达到峰值。RA 诱导组 Pax3的表达在 E14.5显著高于正常组(P <0.05);Pax7的表达则在 E13.5显著高于正常组(P <0.01)。结论:在舌肌分化过程以及RA 诱导腭裂胎鼠的舌发育异常中,miR-1/miR-206与 Pax3/Pax7及 Myf5/MyoD 的表达趋势具有相关性。RA 可能通过下调 miR-1/miR-206而靶向上调 Pax3/Pax7,进而下调 MyoD /Myf5表达,从而抑制舌肌分化,导致舌肌发育异常。  相似文献   
10.

Background

The intracellular signalling mechanisms that regulate ovarian follicle development are unclear; however, we have recently shown differences in the Akt and Erk signalling pathways in dominant compared to subordinate follicles. The aim of this study was to investigate the effects of inhibiting Akt and Erk phosphorylation on IGF- and gonadotropin- stimulated granulosa and theca cell function in vitro, and on follicle development in vivo.

Methods

Bovine granulosa and theca cells were cultured for six days and stimulated with FSH and/or IGF, or LH in combination with PD98059 (Erk inhibitor) and/or LY294002 (Akt inhibitor) and their effect on cell number and hormone secretion (estradiol, activin-A, inhibin-A, follistatin, progesterone and androstenedione) determined. In addition, ovarian follicles were treated in vivo with PD98059 and/or LY294002 in ewes on Day 3 of the cycle and follicles were recovered 48 hours later.

Results

We have shown that gonadotropin- and IGF-stimulated hormone production by granulosa and theca cells is reduced by treatment with PD98059 and LY294002 in vitro. Furthermore, treatment with PD98059 and LY294002 reduced follicle growth and oestradiol production in vivo.

Conclusion

These results demonstrate an important functional role for the Akt and Erk signalling pathways in follicle function, growth and development.  相似文献   
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