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2.
目的探讨精子冷冻环无保护剂玻璃化冷冻方法的可行性。方法正常精液标本上游处理后,进行常规冷冻和冷冻环无保护剂的玻璃化冷冻,复苏后分别从活力参数及电镜下超微结构等指标比较两种冷冻方法的效果。结果两种方法冷冻后精子存活率、活动率之间差异无显著性(48%∶48%;44.5%∶43.5%,P>0.05),但均较未冷冻的89%和88.5%明显下降(P<0.001)。超微结构亦较未冷冻时发生了一定的改变,但核结构基本保持完整。结论精子冷冻环无保护剂的玻璃化冷冻是一种简单、方便而行之有效的冷冻方法。 相似文献
3.
Abstract Migraine without aura is typically considered a female condition. The purpose of this study was to determine if there have
been any changes in the female-to-male ratio of the disease over time. We included in the study all patients with migraine
without aura (n=3457) referred to the Parma University Headache Centre between 1976 and 1995. They were divided into subgroups with respect
to gender and year-range of onset of migraine (before 1960, in the 1960s, in the 1970s, in the 1980s, and between 1990 and
1995). Gender ratio ranged from 3.6:1 (in patients with onset before 1960) to 2.8:1 (in patients with onset in the 1980s),
with no statistically significant changes during the observation period. 相似文献
4.
Kun-xi Qian 《Cardiovascular Engineering》2006,6(1):40-42
To investigate the possibility of a long-term applicable left ventricular assist device, a 23 mm outer diameter and 31 g weight implantable aortic valvo-pump was developed. It consists of a rotor and a stator; the rotor has a driven magnets assemble and an impeller, the stator has a motor coil with iron core and a outflow guide vane. The device locates the position of aortic valve, delivers the blood directly from left ventricle to aorta. Neither connecting conduits nor “bypass” circuits are necessary. Therefore, the device has promisingly better antithrombogenicity than other heart pumps. In hemodynamic testing, the pump can produce a blood flow of 7 l/min volume with 50 mmHg pressure increase at 15,000 rpm rotating speed, and at zero flow rate the pump can maintain a diastolic pressure over 80 mmHg at same rotating speed. For further studies the blood compatibility and the durability of the device are of most importance. 相似文献
5.
A 78-year-old woman is described who presented with a diaphragmatic hernia through the foramen of Morgagni. A definitive
diagnosis was confirmed by a sagittal view on magnetic resonance imaging prior to surgery. The hernia was repaired laparoscopically
under an abdominal wall lifting technique without pneumoperitoneum, and her symptoms completely resolved postoperatively with
no evidence of recurrence. The laparoscopic repair was considered a suitable and safe procedure for the treatment of a Morgagni
hernia.
Received: 3 April 1996/Accepted: 3 May 1996 相似文献
6.
Thermoregulatory heat-loss responses at high ambient temperatures were studied in intact cats and those with bilateral electrolytic lesions in the pontine tegmentum during wakefulness (W), slow-wave sleep (SWS), paradoxical sleep (PS) and PS without atonia induced by the lesions. Panting (respiratory rate 90/min) was present W, SWS, and in some cases, during PS. The percentage of the PS episodes with panting was directly related ambient temperature. In intact cats at 30 °C, panting occurred in 8% of the PS episodes; at 35 °C, in 52%, and at 40 °C, in 77%. The percentage of PS episodes with panting higher in the pontine-lesioned cats (90% at 35 °C), probably another indication of the altered thermoregulation of such animals. Thermoregulatory responses to heat load, and thermoregulation in general, have previously been shown to be suppressed in PS. Because hypothalamic thermosensitive neurons lack thermal responses during PS, the partial activation of heat-loss responses observed here may depend upon the function of extrahypothalamic brainstem areas. 相似文献
7.
Using Queueing Theory to Increase the Effectiveness of Emergency Department Provider Staffing 总被引:4,自引:4,他引:0
Linda V. Green PhD João Soares PhD James F. Giglio MD Robert A. Green MD 《Academic emergency medicine》2006,13(1):61-68
Objectives: Significant variation in emergency department (ED) patient arrival rates necessitates the adjustment of staffing patterns to optimize the timely care of patients. This study evaluated the effectiveness of a queueing model in identifying provider staffing patterns to reduce the fraction of patients who leave without being seen. Methods: The authors collected detailed ED arrival data from an urban hospital and used a Lag SIPP queueing analysis to gain insights on how to change provider staffing to decrease the proportion of patients who leave without being seen. The authors then compared this proportion for the same 39‐week period before and after the resulting changes. Results: Despite an increase in arrival volume of 1,078 patients (6.3%), an average increase in provider hours of 12 hours per week (3.1%) resulted in 258 fewer patients who left without being seen. This represents a decrease in the proportion of patients who left without being seen by 22.9%. Restricting attention to a four‐day subset of the week during which there was no increase in total provider hours, a reallocation of providers based on the queueing model resulted in 161 fewer patients who left without being seen (21.7%), despite an additional 548 patients (5.5%) arriving in the second half of the study. Conclusions: Timely access to a provider is a critical dimension of ED quality performance. In an environment in which EDs are often understaffed, analyses of arrival patterns and the use of queueing models can be extremely useful in identifying the most effective allocation of staff. 相似文献
8.
无神经损伤的胸腰椎骨折的手术治疗 总被引:1,自引:1,他引:0
王强 《中国矫形外科杂志》2007,15(18):1382-1384
[目的]探讨无神经损伤的胸腰椎骨折手术治疗的效果及优点。[方法]2003年7月—2006年7月,手术治疗无神经损伤的A、B型胸腰椎骨折(按AO分类)23例。术前椎体前缘高度丧失均在40%以上;70%患者CT扫描椎管内有骨折块占位。均采用后路椎弓根螺钉内固定系统复位固定,行横突间及椎板间植骨融合术。评价骨折复位及植骨融合情况。[结果]随访时间14~48个月,平均28个月。术后椎体前缘高度及椎间角较术前明显增加(P〈0.05):术后3、6、12个月与术后即刻相比无显著性差异(P〉0.05)。术前椎管狭窄率平均38%,术后3个月为12%,较术前明显减少(P〈0.05)。术后1年植骨融合率为81%。[结论]无神经损伤的胸腰椎骨折手术治疗有助于恢复椎体高度、纠正成角畸形、恢复椎管容积、防止继发性神经损伤及重建脊柱即刻稳定性。为了获得长期稳定性,应辅以植骨融合术。 相似文献
9.
Jocelyne Daigneault Gervais Aubin Fernand Simard Marc De Braekeleer 《Clinical genetics》1991,40(4):298-303
Cystic fibrosis (CF) is an autosomal recessive disorder with a prevalence at birth estimated at 1/2000-1/2500 livebirths in Caucasian populations. Some 127 CF individuals are known in Saguenay-Lac-St-Jean (SLSJ), a geographically isolated region of Quebec. The prevalence at birth was estimated at 1/902 live borns, and the carrier rate was estimated at 1/15 inhabitants in the SLSJ region. The mean inbreeding coefficient was only slightly elevated in the CF group compared with three control groups, and was due to remote consanguinity. The mean kinship coefficient was 2.4 times higher in the CF group than in the control groups. In SLSJ region, the places of origin of the CF individuals and their parents did not show a clustered nonuniform distribution. Endogamy was not higher in the CF group than in control groups. 相似文献
10.