针灸并用矫正胎位的疗效与相关影响因素关系的超声观察

为了探讨影响针刺三阴交，合谷，艾灸至阴穴矫正胎位的因素。对60例胎位不正的孕妇，在B超监视下进行了疗效观察。结果发现疗效的优劣不仅与孕周的大小，羊水的多少，胎儿双顶径的大小有关，且与胎盘附着在子宫的位置有关。     

Compartment syndrome associated with the Lloyd Davies position. Three case reports and review of the literature

The Lloyd Davies position was developed to facilitate access to the pelvis for gynaecological, urological and colorectal procedures. Previous case reports have demonstrated that prolonged adoption (> 4 h) of this position has been associated with the development of bilateral compartment syndrome of the calves. All three patients reported here suffered severe bilateral calf pain despite the use of thoracic epidurals. All three cases required three-compartment fasciotomies and, 6 months after surgery, were all still severely disabled as a consequence of the compartment syndrome. These case reports stress the dangers of use of the Lloyd Davies position for prolonged procedures and demonstrate that some patients are at risk after relatively short periods (< 3 h). Previous case reports and clinical studies have focused on the effect of limb elevation in stirrups on the arterial pressure in the lower limb. We review the pathophysiology of compartment syndrome and consider factors other than a decrease in arterial pressure that may predispose to compartment syndrome during adoption of the Lloyd Davies position.     

Ascending spinal axons that signal the position of the hindlimbs under static conditions: Location and receptor input

Summary Psychophysical experiments have shown that signals from slowly adapting subcutaneous receptors are used to sense limb position under static conditions (i.e., when the joints are stationary). The ascending collaterals of the slowly adapting primary sensory neurons supplying the deep tissues of the hindlimb do not project to the brain via the fasciculus gracilis. In experiments on cats, we have found a population of axons in the lateral fasciculus that signal the position of the ipsilateral hindlimb with a slowly adapting discharge. In the lower thoracic cord these fibers lie between the spinocervical tract and the ventral roots. Although plentiful in the lower thoracic cord, they are sparse or absent below L₃. In addition, a few position signaling axons with crossed input were found in the ventral part of the lateral white matter and in the ventral columns. Since the clinical evidence suggests that the spinal pathway for position sense is uncrossed, we propose that information used for conscious judgments of limb position when the joints are stationary initially ascends via the dorsal columns and then relays to the lateral fasciculus on the same side. These slowly adapting signals also may be used to judge limb position when the joints are moving. To determine whether this slowly adapting discharge originates from muscle or joint receptors, the tendons crossing the ankle joint were exposed but left in continuity and then pulled on while the joint was stationary. In this way individual lateral fascicular axons that signaled ankle flexion, extension, abduction or adduction could be shown to receive a strong excitatory input from muscle receptors. After the muscle tendons crossing the ankle joint were cut, tract fibers signaling ankle flexion, extension, abduction or adduction could no longer be found in this portion of the spinal white matter. Axons signaling clockwise or counterclock-wise twist of the ankle were reduced in number but a few were still present. These results suggest that muscle receptors provide the predominant signal used to sense ankle flexion, extension, abduction and adduction and that receptors in articular tissues may signal ankle twist.     

ACL graft can replicate the normal ligament’s tension curve

The anatomical femoral insertion of the normal anterior cruciate ligament (ACL) lies on the deep portion of the lateral wall of the intercondylar fossa. Following the deep bone–cartilage border, it stretches from 11 oclock high in the notch all the way down to its lowest border at 8 oclock. The tension curve of the normal ACL during passive flexion–extension shows a characteristic pattern with two tension peaks, one in full extension and the other in deep flexion. Low tension in mid-flexion is measured between those two peaks. Standard ACL reconstructions use a femoral insertion at 11 oclock, which results in non-physiological tension curves with one peak in full extension only. The hypothesis was that it is possible to reproduce the typical tension curve of the normal ACL by placing the femoral tunnel into the low part of the normal ACL footprint. In a controlled laboratory study, three different femoral tunnel positions at 9, 10 and 11 oclock were tested in four cadaver knees while using the identical standard tibial tunnel each time. The tension curve was measured during passive flexion–extension with a custom-made tension measurement device, using an artificial Dacron graft. The tension curve of grafts in the 9 oclock tunnels showed the characteristic pattern of the normal ACLs tension curve with tension peaks in extension as well as in deep flexion. The tunnels in the 10 and 11 oclock positions failed to reproduce the normal ACLs tension curve with high-tension values in extension only. Clinical relevance: If an ACL graft is placed low within the normal femoral footprint, the physiological tension curve of the normal ACL can be reproduced.     

Cardiac output and the recumbent position in late pregnancy

Changes in cardiac output were measured by transcutaneous aortovelography in 30 pregnant patients and in 30 control subjects with change of position from the supine. When compared to the supine position, the left and right lateral and left 15 degrees tilt positions caused statistically significant increases in cardiac output, whereas the right 15 degrees tilt position did not. Neither fetal head engagement nor the time spent in each position had significant effects on the changes in cardiac output. It was not possible to identify a subgroup of pregnant patients who were particularly sensitive to changes in posture.     

Myocardial Blood Flow and Coronary Flow Reserve in Children with “Normal” Epicardial Coronary Arteries After the Onset of Kawasaki Disease Assessed by Positron Emission Tomography

Myocardial blood flow (MBF) was investigated in children (14.2 ± 5.01 years) with resolved coronary involvement after the onset of Kawasaki disease and angiographically normal epicardial coronary arteries. Ten asymptomatic children with a history of Kawasaki disease had electrocardiography, echocardiography, and positron emission tomography (PET) 10.3 ± 6.01 years after onset of the acute illness. Myocardial perfusion was assessed by NH₃– PET at rest and after vasodilatation and compared with that of 10 healthy volunteers (26.1 ± 6.3 years). No patient had signs of myocardial ischemia; on echocardiography ventricular function was normal without dyskinetic areas or signs of enlargement or stenosis of the proximal coronary arteries. There was no statistical significant difference between patients and volunteers in MBF at rest (0.86 ± 0.27 vs 0.77 ± 0.17 ml/g/min), whereas MBF after vasodilatation (2.42 ± 0.81 vs 3.10 ± 0.8 ml/g/min) and coronary flow reserve (CFR) (2.89 ± 0.26 vs 4.09 ± 1.01 mmHg/ml/g/min) were significantly attenuated in the Kawasaki group. No stress-induced perfusion defects could be detected. In children with a history of Kawasaki disease and angiographically normal epicardial coronary arteries, there is a significant attenuation of MBF after vasodilatation and a significant reduction of CFR. Impairment of vasoreactive ability may indicate residual damage of the coronary arteries and may be a risk factor for atherosclerosis in adulthood.     

Does circadian variation in risk factors for sudden infant death syndrome (SIDS) suggest there are two (or more) SIDS subtypes?

Sudden infant death syndrome (SIDS) is known to occur more frequently at night. In two studies it has now been shown that a prone sleep position is more strongly associated with SIDS occurring during the day, whereas night-time deaths are more strongly associated with maternal smoking and illness.

Conclusion: This variation, although unexplained, does suggest at least two SIDS subtypes: one related to sleep position and possibly a thermal mechanism, and one related to an uncontrolled inflammatory response to infection predominantly occurring at night. In addition, there are probably other mechanisms that do not show a circadian variation.     

Illusory position shift induced by cyclopean motion

The position of a visual pattern moving within a static aperture appears to be displaced in the direction of motion. This illusory position shift can be induced by luminance-defined as well as contrast-defined motion. The present study used a random-dot binocular correlogram in which a moving square-wave grating was solely defined by binocular correlations. This cyclopean motion was found to induce illusory position shift. Consistent with previous reports on position shift induced by second-order motion, the illusion was smaller than that found in the case of the first-order motion. This pattern of results unequivocally demonstrates the existence of a binocular mechanism mediating this illusion.     

腰麻硬膜外联合分娩镇痛与自由体位待产的探讨

目的探讨自由体位腰麻硬膜外联合镇痛（CSEA）减轻或消除产痛以及对产程、胎儿、分娩方式的影响。方法选择180例无产科、麻醉科禁忌症的初产妇分为自由体位腰麻硬膜外联合分娩镇痛组和硬膜外持续给药分娩镇痛组，每组各90例，在宫口开大2～4cm时，分别施行腰麻硬膜外联合镇痛和硬膜外镇痛，并与条件相似、不用任何镇痛措施的90例初产妇进行对照（对照组）比较三组产痛程度、运动神经阻滞，副作用，产程进展速度、分娩方式及对胎儿的影响。结果自由体位CSEA镇痛有效率较硬膜外组明显提高（P〈0．01），活跃期较对照组缩短，宫颈扩张速度加快，经阴道自然分娩率高于硬膜外组（P〈0．05）。胎儿窘迫及新生儿窒息、产后出血发生率三组比较，无显著性差异。结论自由体位CSEA应用于产科分娩，可达到镇痛要求，产程加速，不增加器械助产率。     

The flash grab effect

When an object moves back and forth, its trajectory appears significantly shorter than it actually is. The object appears to stop and reverse well before its actual reversal point, as if there is some averaging of location within a window of about 100 ms (Sinico et al., 2009). Surprisingly, if a bar is flashed at the physical end point of the trajectory, right on top of the object, just as it reverses direction, the flash is also shifted – grabbed by the object – and is seen at the perceived endpoint of the trajectory rather than the physical endpoint. This can shift the perceived location of the flash by as much as 2 or 3 times its physical size and by up to several degrees of visual angle. We first show that the position shift of the flash is generated by the trajectory shortening, as the same shift is seen with or without the flash. The flash itself is only grabbed if it is presented within a small spatiotemporal attraction zone around the physical end point of the trajectory. Any flash falling in that zone is pulled toward the perceived endpoint. The effect scales linearly with speed, up to a maximum, and is independent of the contrast of the moving stimulus once it is above 5%. Finally, we demonstrate that this position shift requires attention. These results reveal a new “flash grab” effect in the family of motion-induced position shifts. Although it most resembles the flash drag effect, it differs from this in the following ways: (1) it has a different temporal profile, (2) it requires attention, (3) it is about 10 times larger.