抑郁症患者静息状态的功能磁共振成像研究

目的 了解在静息状态下抑郁症患者脑区的局部一致性特点.方法 采用功能磁共振成像(fMRI)技术,检测静息状态下27例抑郁症患者(患者组)和性别、年龄、受教育程度均与患者相匹配的27名正常人(对照组)的脑功能活动,并对两组进行比较.利用局部一致性方法 分析fMRI数据,用SPM2软件进行配对t检验(P＜0.005).结果 与对照组相比,患者组双侧额中回、右额下回、右颞上回、左前扣带回、右后扣带回、右岛叶、双侧豆状核、双侧屏状核、左尾状核局部一致性显著增高(P＜0.005,未校正,体素值＞10);未显示脑区有明显的局部一致性减低.结论 抑郁症患者神经环路脑区局部在静息状态下具有很高的一致性,其局部一致性的增高可能参与了抑郁症的代偿机制.     

腔隙性脑梗塞患者的高粘血症与高凝状态

研究腔隙性脑梗塞病人是否并发高粘血症和高凝血症。方法：检测３２例腔隙性脑梗塞患者的血液流变性和血液凝固性。结果：血液流变性指标加、Ｐ、ＥＰＴ、ＨＣＴ、ＥＳＲ和Ｆｉｂ腔隙性脑梗塞病人较对照组有非常显著的差异（Ｐ＜０．０５～０．０１），另外其ＰＡｇＴ、ＶＷＦ：ＡＧ、Ｆｎ增高，ＡＴⅢ：Ａ和ＰＬＧ降低均表现血液有高凝状态。结论：腔隙性脑梗塞患者多伴有高粘血症与高凝血症，因此组织灌注不足，这在腔隙性脑梗塞发病和进程中是一个危险因素。     

假肥大型肌营养不良症患者及携带者的致病基因突变检测

目的 检测假肥大型肌营养不良症患者及携带者的dystrophin基因致病突变类型,为防止假肥大型肌营养不良症的再发提供信息.方法 利用多重引物连接依赖式扩增技术和变性高效液相色谱技术检测临床研究发现的20例假肥大型肌营养不良症患者的DMD基因突变.结果 缺失突变10例,重复突变1例,终止密码子突变4例,5例未发现致病突变.结论 通过致病突变的检测可以为防止患者家庭假肥大型肌营养不良症的再发提供优生优育指导.     

Variations in creatine kinase activity and reactive oxygen species levels are involved in capacitation of bovine spermatozoa

The generation of reactive oxygen species (ROS) is associated with some factors such as oxidative substrate sources, mitochondrial function and NAD(P)H oxidase activity. In bovine spermatozoa, heparin capacitation produces a respiratory burst sensitive to diphenyleneiodonium (DPI). Creatine kinase (CK) is related to extramitochondrial ATP disponibility. Our purpose was to determine the variation in ROS level and its relation with NAD(P)H oxidase sensitive to DPI and CK participation, as factors involved in redox state and energy generation in capacitation. The chlortetracycline technique was used to evaluate capacitation. CK activity and ROS level were measured by spectrophotometry and spectrofluorometry respectively. The capacitation percentage was increased by heparin or quercetin treatment (P < 0.05) and no significant differences in sperm viability were observed. Samples treated with heparin or quercetin maintained the same ROS level as control (238.62 ± 23.47 arbitrary units per 10⁸ spermatozoa) (P > 0.05). CK activity decreased by 50% with heparin or quercetin (P < 0.05). In DPI presence, capacitation was inhibited and differential CK activities and ROS level variations were observed in heparin- or quercetin-treated samples (P < 0.05). In cryopreserved bovine spermatozoa, capacitation requires equilibrium between oxidative damage susceptibility and ROS levels. CK activity is associated with redox state variation and energy sources. In conclusion, capacitation induction depends on NADPH oxidase and the shuttle creatine–creatine phosphate, both sensitive to DPI.     

Albumin thiol oxidation and serum protein carbonyl formation are progressively enhanced with advancing stages of chronic kidney disease

Background  Oxidative stress is enhanced in advanced chronic kidney disease (CKD) patients and recognized as a main contributor to cardiovascular disease. Carbonyl stress is also known to be enhanced in advanced CKD; however the precise relationship between oxidative stress and carbonyl stress is not clear. The aim of this study was to investigate potential relationships between oxidative stress, carbonyl stress, and renal function among predialysis patients with CKD. Methods  A total of 32 predialysis CKD patients (22 male, 10 female) were divided into four groups according to their values for creatinine clearance (Ccr) (group A, ≥60 ml/min; group B, 45–59 ml/min; group C, 30–44 ml/min; group D, ≤29 ml/min). As main markers of oxidative and carbonyl stresses, the redox state of Cys-34 (free thiol group) of human serum albumin [HSA(Cys-34)-redox] and the carbonyl content of serum proteins were employed, respectively. Results  The values for the fraction of both reversibly oxidized HSA [f(HNA-1)] and irreversibly oxidized HSA [f(HNA-2)] significantly increased with a decrease in renal function (group A, 21.0 ± 3.4 and 1.8 ± 0.3%; group D, 31.1 ± 4.1 and 2.7 ± 0.9%, respectively). The value for carbonyl content also significantly increased with a decrease in renal function (group A, 0.7 ± 0.1 nmol/mg protein; group D, 1.1 ± 0.2 nmol/mg protein). There was a significant positive correlation between carbonyl content and the f(HNA-2) value, while such a correlation was not observed between carbonyl content and the f(HNA-1) value, suggesting that there is a close relationship between serum protein carbonylation and irreversible albumin thiol oxidation. Conclusions  There is a close relationship between oxidative stress and carbonyl stress and these are enhanced in correlation with the level of renal dysfunction among predialysis CKD patients.     

Is TrueFISP a gradient‐echo or a spin‐echo sequence?

It is commonly accepted that TrueFISP (balanced FFE, FIESTA) belongs to the class of gradient-echo (GRE) sequences. GRE sequences are sensitive to dephasing effects of the transverse magnetization between the excitation pulse and echo acquisition, and phase coherence is only established directly after and before excitation pulses. However, an analysis of the phase evolution of transverse magnetization in a TrueFISP experiment shows very close similarities to the echo formation of a spin-echo (SE) experiment. If dephasing between excitation pulses is below +/-pi, TrueFISP exhibits a nearly complete refocusing of transverse magnetization at TE = TR/2. Only signals acquired before and after TR/2 show an additional T*2 sensitivity.     

CNS side effects of centrally-active antihypertensive agents: A prospective,placebo-controlled study of sleep,mood state,and cognitive and sexual function in hypertensive males

A prospective, placebo-controlled, comparative evaluation was conducted on two widely prescribed, sympatholytic antihypertensive agents with known CNS effects. In order to separately assess these effects in younger and older male hypertensives, patients were assigned to either of two treatment studies based on age. For study I, 24 males aged 31–59 (mean=49.8; SD=7.4) with mild hypertension (mean DBP=100.2 mm Hg; SD=8.0) received 3 months of treatment with propranolol (20–80 mg bid), clonidine (0.1–0.3 mg bid), or double-blind placebo in a counterbalanced, crossover design. For study II, 23 elderly hypertensive males (mean DBP=102.6 mm Hg; SD=8.2) aged 60–78 years (mean=65.1; SD=4.6) were randomized to propranolol (20–40 mg bid) or double-blind placebo therapy. Patients received cognitive testing, mood assessments, and all-night polysomnographic evaluations before and after each treatment period. Multivariate analysis of EEG sleep data was statistically significant for study I, with significant univariate effects on four of the six primary sleep variables: total sleep time was reduced, sleep maintenance decreased, REM latency increased, and percent total REM time was reduced. A similar MANOVA analysis for the effects of treatment on the sleep of older patients (study II) was not significant. However, propranolol administration was found to be associated with a significant decline in cognitive performance in these patients. Significant mood effects were observed with each of the study drugs, and nocturnal penile tumescence (NPT) was significantly decreased in both younger and older patients. Overall, this research suggests that distinct patterns of CNS effects are associated with each of the antihypertensive agents studied.     

口腔修复门诊老年病人心理特点分析及对策

老年患者占口腔修复科临床接诊病人的很大部分，本文从医学伦理学角度入手对门诊老年病人心理状态进行分析，探讨相应对策，以寻求临床上医患更好地合作。作者的建议主要包括：(1)提高医师自身综合素质。(2)尊重、爱护老年患者，满足老年患者的合理要求。(3)治疗过程中应树立高度的道德责任感与正确的伦理道德观。     

Balanced alternating steady-state elastography.

A conventional balanced steady-state free precession (b-SSFP) sequence scheme was modified such that the dynamic equilibrium becomes very sensitive to small cyclic displacements, generating two distinct and alternating steady states. This novel technique is proposed for the visualization of propagating transverse acoustic shear waves, as used in MR elastography (MRE) to determine the mechanical properties of materials or in vivo soft tissue. Experiments with tissue-like agarose gel phantoms and simulations demonstrate that the novel sequence offers an increase in phase sensitivity by about one order in magnitude compared to standard motion-encoding methods. In addition, the new method benefits from the very short acquisition times achieved by b-SSFP protocols.     

Spatial visual acuity of the eagle Aquila audax: a behavioural, optical and anatomical investigation

Behavioural acuity of the wedge-tailed eagle was determined across a range of luminance. Maximum acuity is between 132 and 143 c/deg and with decreasing luminance acuity declines sharply. The maximum anatomical resolving power of the eagle's deep fovea was calculated as 140 c/deg. This calculation was based upon ophthalmoscopic measurement of posterior nodal distance and estimates of photoreceptor spacings made from fixed foveal tissue and corrected for shrinkage. Maximum behavioural acuity and anatomical resolving power correspond closely and approach the highest frequency (157 c/deg) transmitted by the minimum pupil diameter of the eye. These findings are discussed with reference to current theories of visual functioning.