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1.
Callosal connections of suprasylvian visual areas in the cat   总被引:2,自引:0,他引:2  
After horseradish peroxidase injections in cat's lateral suprasylvian visual area and in areas 17 and 18, labeled callosal neurons are found within the various subdivisions of the lateral suprasylvian area, mostly in regions where the area centralis and vertical meridian are represented. The homotopic callosal projections from lateral suprasylvian area to lateral suprasylvian area originate almost exclusively from layer III. The heterotopic callosal projections from the lateral suprasylvian area to areas 17 and 18 originate mainly from layer VI but also from layer III. Callosal neurons in the lateral suprasylvian area are pyramidal cells (layers III and VI), fusiform and triangular cells (layer VI).The distribution of callosal neurons in the lateral suprasylvian area is similar to that previously found in areas 17 and 18 in the sense that in all these areas callosal neurons are preferentially located near the vertical meridian representation within two radially separated laminae. However, the preponderance of layer VI neurons in the projection from the lateral suprasylvian area to contralateral areas 17 and 18 is different from what was observed in other callosal connections. Since layer VI usually gives rise to corticothalamic projections it is possible that similar feed-back mechanisms may modulate the information sent to the lateral suprasylvian area from the thalamus and the primary visual areas.  相似文献   
2.
目的 分析VERION数字导航系统测量角膜曲率和散光的可重复性及其与iTrace、Lenstar LS900、手动角膜曲率计检测结果的一致性.方法 对62名年龄相关性白内障患者分别用上述四种仪器进行角膜生物测量,记录并分析陡峭轴角膜曲率(steep keratometry,Ks)、平坦轴角膜曲率(flat keratometry,Kf)、散光幅度、散光轴位、矢量参数J0和J45.分析VERION测量的可重复性,并比较VERION与其他三种仪器测量结果的一致性.结果 用组内相关系数(intraclass correlation coefficient,ICC)和克隆巴赫系数(Cronbach's alpha,α)分别对Ks、Kf、散光幅度、散光轴位、J0以及J45做出分析,结果均大于0.9(均为P<0.001),提示VERION测量角膜曲率及散光的可重复性极好.VERION测量的Ks、散光幅度均高于iTrace(均为P<0.05),其余指标的差异无统计学意义(均为P>0.05).Bland-Altman分析显示J0、J45及散光轴位的95% LOA分别为(-0.31 ~0.35)D、(-0.25~0.31)D、-13.5°~12.3°.二者测量的散光轴位差小于10°者占总体的77% (48/62),在合并角膜散光大于1D的患者中占91% (42/46).VERION与Lenstar LS900测量结果仅J45差异有统计学意义(P<0.05),其余指标差异无统计学意义(均为P>0.05).Bland-Altman分析发现J0、J45及散光轴位的95% LOA分别为(-0.25 ~0.31)D、(-0.27 ~0.36)D、-13.5°~11.0°.二者测量的散光轴位差小于10°者占总体的85%(53/62),在合并角膜散光大于1D的患者中占93%(43/46).VERION与手动角膜曲率计检测的Kf、散光幅度差异有统计学意义(均为P<0.05),其余指标差异无统计学意义(均为P>0.05).Bland-Altman分析显示J0、J45及散光轴位的95% LOA分别为(-0.38 ~0.35)D、(-0.41 ~0.42)D、-12.6° ~16.4°.二者测量的散光轴位差小于10°者占总体的81% (50/62),在合并角膜散光大于1D的患者中占91%(42/46).结论 VERION在测量角膜曲率及散光方面具有良好的可重复性.其与iTrace、Lenstar LS900和手动角膜曲率计在角膜曲率、散光幅度的测量方面一致性较好,但对散光轴位的测量差别较大.  相似文献   
3.

Purpose

Transient elastography (TE) is routinely used for noninvasive staging of hepatic fibrosis. The objective of the present study was to investigate the role of TE (FibroScan) in determining changes in liver congestion in patients with Budd–Chiari syndrome (BCS) treated by endovascular interventions and determine the effects of pretreatment Meta-analysis of Histological Data in Viral Hepatitis (METAVIR) fibrosis score on posttreatment liver stiffness (LS).

Materials and Methods

Twenty-five patients undergoing endovascular procedures for treatment of BCS underwent TE immediately before and within 24 hours after the procedure. Fifteen patients available for 3-month follow-up were again subjected to TE. Mean LS values before and after intervention were compared in 12 of these patients for whom METAVIR scores were available. Pressure gradient changes across the stenosed hepatic veins/inferior vena cava were measured during the procedure. Statistical analysis of these data was performed by Wilcoxon signed-rank test, Mann–Whitney U test, and Pearson product–moment correlation coefficient.

Results

Significant differences were found between mean LS measurements before and within 24 hours after intervention (Z-score = 4.372) and between the mean values obtained before and 3 months after treatment (Z-score = 3.408). Mean changes in LS values after intervention in patients with METAVIR fibrosis scores ≤ 2 and > 2 were not significant. There was no correlation between changes in pressure gradients and the degree of LS.

Conclusions

TE is a useful tool to assess the reduction in hepatic congestion in patients with BCS undergoing endovascular interventions.  相似文献   
4.
5.
During the recording time of lung sound (LS) signals from the chest wall of a subject, there is always heart sound (HS) signal interfering with it. This obscures the features of lung sound signals and creates confusion on pathological states, if any, of the lungs. A novel method based on empirical mode decomposition (EMD) technique is proposed in this paper for reducing the undesired heart sound interference from the desired lung sound signals. In this, the mixed signal is split into several components. Some of these components contain larger proportions of interfering signals like heart sound, environmental noise etc. and are filtered out. Experiments have been conducted on simulated and real-time recorded mixed signals of heart sound and lung sound. The proposed method is found to be superior in terms of time domain, frequency domain, and time–frequency domain representations and also in listening test performed by pulmonologist.  相似文献   
6.
Virtually every eukaryotic cell has an endogenous circadian clock and a biological sex. These cell-based clocks have been conceptualized as oscillators whose phase can be reset by internal signals such as hormones, and external cues such as light. The present review highlights the inter-relationship between circadian clocks and sex differences. In mammals, the suprachiasmatic nucleus (SCN) serves as a master clock synchronizing the phase of clocks throughout the body. Gonadal steroid receptors are expressed in almost every site that receives direct SCN input. Here we review sex differences in the circadian timing system in the hypothalamic–pituitary–gonadal axis (HPG), the hypothalamic–adrenal–pituitary (HPA) axis, and sleep–arousal systems. We also point to ways in which disruption of circadian rhythms within these systems differs in the sexes and is associated with dysfunction and disease. Understanding sex differentiated circadian timing systems can lead to improved treatment strategies for these conditions.  相似文献   
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9.
Over the recent couple of decades, pharmaceutical field has embarked most phenomenal noteworthy achievements in the field of medications as well as drug delivery. The rise of Nanotechnology in this field has reformed the existing drug delivery for targeting, diagnostic, remedial applications and patient monitoring. The convincing usage of nanotechnology in the conveyance of medications that prompts an extension of novel lipid-based nanocarriers and non-liposomal systems has been discussed. Present review deals with the late advances and updates in lipidic nanocarriers, their formulation strategies, challenging aspects, stability profile, clinical applications alongside commercially available products and products under clinical trials. This exploration may give a complete idea viewing the lipid based nanocarriers as a promising choice for the formulation of pharmaceutical products, the challenges looked by the translational process of lipid-based nanocarriers and the combating methodologies to guarantee the headway of these nanocarriers from bench to bedside.  相似文献   
10.
Crude extract of Rheum palmatum L (CERP) has been used to treat different diseases in the Chinese population for decades. In this study, we investigated the effects of CERP on LS1034 human colorectal cancer cells in vitro and also examined possible mechanisms of cell death. Flow cytometric assays were used to measure the percentage of viable cells, cell cycle distribution including the sub‐G1 phase (apoptosis), the activities of caspase‐8, ‐9, and ‐3, reactive oxygen species (ROS) and Ca2+ levels, and mitochondrial membrane potential (ΔΨm). DNA damage, nuclei condensation, protein expression, and translocation were examined by Comet assay, 4′‐6‐diamidino‐2‐phenylindole (DAPI) staining, Western blotting, and confocal laser system microscope, respectively. CERP induced apoptosis as seen by DNA fragmentation and DAPI staining in a concentration‐ and time‐dependent manner in cancer cells. CERP was associated with an increase in the Bax/Bcl‐2 protein ratio and CERP promoted the activities of caspase‐8, ‐9, and ‐3. Both ROS and Ca2+ levels were increased by CERP but the compound decreased levels of ΔΨm in LS1034 cells. Laser confocal microscope also confirmed that CERP promoted the expressions of AIF, Endo G, cytochrome c, and GADD153 to induce apoptosis through mitochondrial‐dependent pathway. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 969–980, 2014.  相似文献   
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