一期后、前路手术治疗发育性颈椎管狭窄症合并巨大椎间盘突出

目的：评价一期后、前路手术治疗发育性颈椎管狭窄合并巨大椎间盘突出的特点及疗效。方法：回顾分析2002年2月至2006年1月接受该术式的21例患者的临床资料,对手术前后临床表现、JOA评分、MRI影像变化以及术后神经功能改善率及并发症进行总结分析。结果：术后未发生神经系统症状加重、感染及内固定失效等并发症。获得1年以上随访者21例,平均随访时间为29.2个月,术后3个月、12个月时神经功能改善率分别为：58%、66%;16例获得2年以上随访者神经功能改善率为71%。结论：一期后、前路手术治疗发育性颈椎管狭窄合并巨大椎间盘突出可缩短治疗周期,相对节省治疗费用,同时解除了硬膜囊前、后方的压迫,减压彻底,疗效满意。     

Changes in microtubule-associated protein-2 (MAP2) expression during development and after status epilepticus in the immature rat hippocampus

In this study, we analyzed the spatiotemporal expression patterns of the high-molecular weight (MAP2a and b) and low-molecular weight (MAP2c and d) cytoskeletal microtubule-associated protein-2 (MAP2) isoforms with Western blotting, and the cellular localization of the high-molecular weight MAP2 isoforms with immunocytochemistry in the hippocampi of 1- to 21-day-old rats. Moreover, the temporal profile (from 30 min to 1 week) of MAP2 isoform reactivity to kainic acid-induced status epilepticus was studied in P9 rats. During development, the expression of the high-molecular weight MAP2 isoforms significantly increased, while the low-molecular weight isoforms decreased, the most prominent changes occurring during the second postnatal week. This developmental increase in the high-molecular weight MAP2 expression was also confirmed with immunocytochemistry, which showed increased immunoreactivity, particularly in the molecular layers of the dentate gyrus, and in CA1 and CA3 stratum radiatum. In 9-day-old rats, status epilepticus resulted in a rapid transient increase (about 210%) in the high-molecular weight MAP2 expression, without any effect on the low-molecular weight MAP2. Moreover, disturbed dendritic structure in the CA1 and CA3 stratum radiatum was manifested as formation of varicosities 3h after the kainic acid treatment. The strictly developmentally regulated MAP2 isoform expression suggests different functional roles for these proteins during the postnatal development in the rat hippocampus. Moreover, high-molecular weight MAP2s may play a role in nerve cell survival during cell stress.     

Development of sample handling procedures for foods under USDA's National Food and Nutrient Analysis Program

The National Food and Nutrient Analysis Program (NFNAP) was implemented in 1997 to update and improve the quality of food composition data maintained by the United States Department of Agriculture (USDA). NFNAP was designed to sample and analyze frequently consumed foods in the U.S. food supply using statistically rigorous sampling plans, established sample handling procedures, and qualified analytical laboratories. Methods for careful handling of food samples from acquisition to analysis were developed to ensure the integrity of the samples and subsequent generation of accurate nutrient values. The infrastructure of NFNAP, under which over 1500 foods have been sampled, mandates tested sample handling protocols for a wide variety of foods. The majority of these foods were categorized into several major areas: (1) frozen foods; (2) fresh produce and/or highly perishable foods requiring refrigeration; (3) fast foods and prepared foods; (4) shelf-stable foods; (5) specialized study and non-retail (point of production) foods; and (6) foods from remote areas (e.g. American Indian reservations). This paper describes the sample handling approaches, from the collection and receipt of the food items to the preparation of the analytical samples, with emphasis on the strategies developed for those foods. It provides a foundation for developing sample handling protocols of foods to be analyzed under NFNAP and for other researchers working on similar projects.     

我国环卫设备的现状与发展趋势——环卫设备的标准化、系列化

介绍了我国环卫设备的发展现状,并提出了存在的一些问题.根据我国环卫产业政策的有关要求:论述了各种环卫设备研究和开发的方向,指出大力推进环卫机械设备的标准化、系列化、通用化、规模化是社会主义市场经济发展和环卫业发展的需要.     

Developmental changes in intracellular pH buffering power in smooth muscle

 Intracellular pH (pH_i) is known to modulate contraction. Neonatal tissues can differ from adult tissue in contractile response to stimuli known to alter pH_i e.g. hypoxia. Changes of pH are attenuated by buffering, thus any difference in buffering power (β) between tissues could affect their functional response to pH_i perturbation. Similarly the extent to which any extracellular pH (pH_o) alteration is transmitted into a pH_i change will also influence function. We have therefore determined the intrinsic β and effect of pH_o change on pH_i in neonatal and adult ureteric, uterine and gastric smooth muscles using the pH-sensitive fluorophore carboxy-SNARF. β was found to be similar in the three adult tissues, but there were significant differences between neonatal tissues. In contrast, we found little difference in the amount of pH_i change produced by pH_o change between neonatal and adult tissues from the same smooth muscle, but a difference between smooth muscles. These data highlight significant differences between smooth muscles and their developmental state, which may contribute to different degrees of protection when pH is perturbed. Received: 17 October 1997 / Received after revision: 27 November 1997 / Accepted: 28 November 1997     

Renal brush border sodium-sulfate cotransport in guinea pig: effect of age and diet

  Renal adaptation to changes in inorganic sulfate intake and age was studied by comparing sulfate uptake by proximal tubule brush border membrane vesicles (BBMV) from guinea pigs of different ages on relatively high- or low-sulfate diets. Adult (>60 days) or young guinea pigs (<25 days) were fed either a control diet (0.28% sulfur content), a sulfur-free diet, or a high-sulfate diet. After 5 days on the diet, BBMV were obtained and kinetic analysis of ³⁵sulfate uptake was determined. In adult guinea pigs, the low-sulfate diet produced a significant increase in apparent maximal velocity (V _max). In young guinea pigs, a lower sulfate intake did not appreciably increase V _max, but a high-sulfate intake produced a reduction in V _max. The affinity for sulfate (K _m) was not changed in either age group. The dietary sulfate intake did not alter sodium gradient dependent-D-glucose or ³²phosphate V _max. In conclusion, our data indicate that renal inorganic sulfate BBMV uptake is regulated and responds to conditions of increased need (i.e., during the growth phase in young animals and during periods of decreased sulfate availability in adult animals) by increasing BBMV V _max. Received September 9, 1994; received in revised form March 18, 1997; accepted March 20, 1997     

Development and proliferation of lymphocytes in mice deficient for both interleukins-2 and -4

Interleukin (IL)-2 and IL-4 are considered as important regulators of growth and differentiation of lymphocytes. We report that in mice made deficient for both IL-2 and IL-4 by gene targeting all major T cell subsets and B cells were normal, indicating that IL-2 and IL-4 are not essential for development of the immune system. Paradoxically, proliferation of T cells was increased in both IL-2- and IL-4-deficient homozygous mice.     

Strategy and timing of peripheral nerve surgery

The authors review the latest theories of peripheral nerve regeneration and repair. They present their research on nerve regeneration including the alterations in the mother cell body, and in the distal part of the axon, and the time required to reach the best production of amino acids for cytoskeleton reconstruction. Other research of particular interest which is presented regards the chemotactic arrangement of motor and sensory axons inside a vein. This research has shown that the axons are able to find their way to the appropriate (sensory or motor) distal endoneural tubes.Adoption phenomena are also presented.The discussion of surgery includes the type (suture, glueing, grafts, tubulization) and the time of surgical repair. Timing and repair strategies are related to the site of the lesion (which can require that a greater or smaller amount of cytoskeleton be reconstructed), the type of the injury, the state of surrounding tissues, the age of the patients, injuries to muscles, tendons, bones, vessels and skin. A scheme of strategy is proposed.     

Hand and gender differences in the organization of aiming in 5-year-old children.

The aim of the present study was to analyze the organization of aiming movements in right-handed children aged 5 years, depending on gender and hand used to perform the task. We first tested the hypothesis that aiming movements are predominantly organized in a feed-forward manner before the age of six. Using a direction pre-cueing protocol, we analyzed the effect of gender and hand used to perform the task on reaction time (RT), movement time (MT), spatial accuracy (SA) and acceleration profiles (APs) in children aged 5 years. Differences in RT between the uncued and pre-cued conditions suggest that the direction is actually specified prior to the execution of the movement at the age of five. However, the results also show significant hand and gender effects on MTs, spatial error and APs. Specifically, in girls, MT and kinematics profiles vary as a function of hand and target localization, whereas this is not the case in boys. In addition, SA is lower when aiming with the non-dominant hand in boys, but not in girls. These results suggest that multiple movement strategies are already available to the child at the age of five. Girls appear to be able to change movement strategy as a function of the constraints of the task, resulting in a stability of spatial accuracy (SA). On the contrary, the functional advantage of the right hand on MT and SA generally reported in right-handed males is not present in the boys at the age of five.     

Temporal Lobe Epileptogenesis and Epilepsy in the Developing Brain: Bridging the Gap Between the Laboratory and the Clinic. Progression, But in What Direction?

Summary:  The origins of human mesial temporal lobe epilepsy and hippocampal sclerosis are still not well understood. Hippocampal sclerosis and temporal lobe epileptogenesis involve a series of pathologies including hippocampal neuronal loss and gliosis, axonal reorganization, and maybe hippocampal neoneurogenesis. However, the causality of these events is unclear as well as their relation to the factors that may precipitate epileptogenesis. Significant differences between temporal lobe epileptogenesis in the adult and immature brain may require differential approaches. Hereditary factors also may participate in some cases of hippocampal sclerosis. The key point is to identify the significance of these age-dependent changes and to design preventive treatments. Novel strategies for the prevention and treatment of mesial temporal lobe epilepsy and hippocampal sclerosis may include rational use of neuroprotective agents, hormonotherapy, immunizations, and immunotherapy.