椎弓根螺钉联合椎间植骨融合器治疗腰椎滑脱症的远期疗效分析

[目的]探讨椎弓根螺钉系统联合椎间植骨融合器治疗峡部不连性腰椎滑脱症的远期疗效。[方法]自1996年10月~2002年10月本组收治峡部不连性腰椎滑脱症105例,随访资料齐全者86例。所有患者均行椎弓根螺钉系统复位滑脱,椎间植骨融合器行椎间融合固定。62例患者中1枚融合器从后斜向前呈45°植入,24例为2枚融合器从后向前垂直植入。随访测定固定节段的椎体间有无移位、滑脱有无复发,比较术前、术后2周及随访时固定椎间隙高度与近端第2椎间隙高度比值的变化。[结果]随访2~8年,平均35个月。根据NaKai评分标准,本组优56例,良13例,可17例,优良率为80.23%。Ⅰ度腰椎滑脱19例术后全部解剖复位;Ⅱ度腰椎滑脱51例中5例遗留Ⅰ度滑脱;Ⅲ度腰椎滑脱16例中4例留有Ⅰ度滑脱。末次随访时使用1枚融合器或2枚融合器所固定的椎间隙高度与近端第2椎间隙高度的比值与术后2周时的比值相比有所减低,滑脱无复发。[结论]椎弓根螺钉加椎间植骨融合器治疗腰椎滑脱症手术疗效满意,显著提高融合率,预防神经根管狭窄、神经卡压的发生,减少术后断钉和滑脱复发等问题。     

Exo-focal postischemic neuronal damage in the rat brain: alteration of [H]forskolin binding using in vitro autoradiography

We studied the alteration of intracellular signal transduction using quantitative autoradiography of the second messenger system in order to clarify the mechanisms of delayed neuronal damage in the remote areas of rat brain after transient focal ischemia. Chronological changes of [³H]forskolin binding sites were measured to demonstrate the striatal-nigral pathway after 90 min of right middle cerebral artery (MCA) occlusion and after such occlusion followed by 3 h, 6 h, 1 day, 3 days, 1 week, 2 weeks and 4 weeks of recirculation. [³H]Forskolin binding sites were found to be markedly decreased in the lateral segment of the caudate putamen supplied by the occluded MCA after 90 min of ischemia with no recirculation. On the contrary, there was no alteration on day 1, but 3 days after ischemic insult, marked reduction of [³H]forskolin binding sites was observed in the ipsilateral substantia nigra which lay outside the ischemic areas. This postischemic delayed phenomenon observed in the substantia nigra developed concurrently with ⁴⁵Ca accumulation, which was detected there in our previous study. The delayed reduction of [³H]forskolin binding sites in the substantia nigra observed in the present study indicates that striatonigral terminal degeneration at presynaptic sites is caused by precedent ischemic damage of the ipsilateral caudate putamen and that exo-focal postischemic neuronal death is caused by a transsynaptic process associated with the ischemic foci.     

Synaptic organization of cortico-cortical connections from the primary visual cortex to the posteromedial lateral suprasylvian visual area in the cat

The synaptic organization of the projection from the cat striate visual cortex to the posteromedial lateral suprasylvian cortical area (PMLS) was examined. The anterograde tracer Phaseolus vulgaris leucoagglutinin (PHA-L) was iontophorectically delivered into area 17, and anterogradely labeled fibers were revealed in PMLS by means of an immunocytochemical detection method. Most axons and presumptive terminal swellings were found in layers III and IV. The neuronal elements (n = 190) that were postsynaptic to anterogradely labeled boutons were quantitatively analyzed. All anterogradely labeled cortico-cortical boutons (n = 182) established type 1 synapses. The results show that 83% of the postsynaptic targets were dendritic spines, probably belonging to pyramidal cells. Dendritic shafts constituted 17% of the targets. The dendritic shafts postsynaptic to cortico-cortical boutons were studied for the presence of gamma-aminobutyric acid (GABA) with a postembedding immunogold method. Most dendritic shafts (85%) that were tested were found to be GABA-positive, demonstrating that they originate from local inhibitory neurons. Taking into account that most postsynaptic targets were spines and extending the results of the immunocytochemical testing to the total population of postsynaptic dendrites, it was calculated that at least 14% of targets originated from GABA-positive cells. Thus cortico-cortical axons establish direct monosynpatic connections mainly with pyramidal and to a lesser extent with GABAergic nonpyramidal neurons in area PMLS, providing both feedforward excitation and feedforward inhibition to a visual associational area known to be involved in the processing of motion information. The results are consistent with previously demonstrated deficits in physiological properties of neurons in PMLS following removal of cortico-cortical afferents.     

护理本科生双导师制带教模式的实践

目的 探索适合护理本科生的临床带教模式.方法 将2001级和2000级护理本科生分为实验组(n=24)和对照组(n=38),对照组给予传统带教模式带教,实验组采用双导师制带教模式,即每名学生在临床实习期间,由1名临床专科导师负责其本科室专科知识方面的指导,1名全程导师负责其实习全过程的督导及检查工作,护理部在学生实习结束前进行带教满意率测评及实习效果评价,并与对照组进行比较.结果 两组对医院带教很满意率、学生护理理论、操作技能考核成绩、论文书写优良率比较,差异有显著性意义(均P＜0.01).结论 双导师制可提高带教质量,是受学生好评和欢迎的带教模式.     

Implication of the systolic hump in systemic arterial pressure waves

The systolic hump in the aortic blood pressure wave is defined as the aorticresistance component proportional to the aortic blood flow superimposed on the windkessel component. An electrical analogue comprising a series resistance (aortic resistance) plus a resistance (peripheral resistance) and capacitance (aortic compliance) in parallel (i.e. windkessel component) is used for analysis. Curve fitting using the leastsquares method is performed on calculated and measured blood pressure waves from dogs under haemodynamical conditions induced by infusion of three drugs (noradrenaline, isoproterenol and acetylcholine). The curve fitting RMS (root mean square) errors are <3% for blood pressure waves and <30% for blood flow waves, with good agreement between measured and calculated blood flow waveforms. Infusion of noradrenaline and acetylcholine is found to induce a significant decrease and increase in the aortic resistance, respectively. Although only a small fraction of the blood pressure wave, the systolic hump has a marked effect on the systolic pressure waveform.     

Chronological changes in the complement system in sepsis

The time courses of serum complement levels and the severity of sepsis were compared in two groups of septic patients, one in which the patients survived (surviving group) and one in which they did not (nonsurviving group). The components of the complement system, namely, C3a, C4a, C5a, CH50, C3, C4, and C5, were measured at several points in time after the diagnosis of sepsis had been established. A 2-antibody radioimmunoassay was used to measure C3a, C4a, and C5a; the latex agglutination test was used to measure C3 and C4; nephelometry was used to measure C5; and Meyer's 50% hemolysis method was used to measure CH50. Following the diagnosis of sepsis, the levels of CH50, C3, and C4 were significantly lower in the nonsurviving than the surviving group, while the levels of C3a and C4a were significantly higher in the nonsurviving than the surviving group. The C5a levels were significantly higher in the nonsurviving than the surviving group, although no significant intergroup differences were subsequently noted. These results suggest that the serum levels of C3a, C4a, C5a, CH50, C3, and C4 could serve as indices of the severity of sepsis. Thus, monitoring the complement system may be useful for predicting the outcome of patients with sepsis.     

The interactive role of mucosal T lymphocytes in intestinal growth, development and enteropathy

Abstract Over the past 15–20 years, research has progressively focused on the mucosal T cell as the central factor in the initiation of physiological or pathological changes, first in the growth and maturation of the early (postnatal) intestine, and second in adult-type enteropathies resulting from sensitivity to either food or pathogen-derived antigens. T cell-mediated events may be measured, for example, in terms of specific immunopathologic patterns of change and injury, such as type 1 (lymphocyte infiltration), type 2 (crypt hyperplasia) and type 3 (flat-destructive), which can be recognized and quantitated microscopically; by determination of lymphocyte reactivity through secretion of interleukin-2 receptors (IL-2R) into plasma or expression by mucosal lymphocytes; by quantitation of lymphocyte subsets emigrating into inflamed tissues by immunoperoxidase-labelled monoclonal antibodies; or by the determination of T cell receptor polymorphisms. Alterations in intestinal growth, structure and function at weaning are likely to be T cell-mediated as they are analogous to the same type 1/2 lesions that reflect modulation of adult mucosal architecture in food and parasite-induced hypersensitivity reactions. Enteropathies associated with HIV infection and T cell deficiency display a milder degree of villous flattening and impaired crypt hyperplasia than that typical of gluten-sensitivity, suggesting a reversion to lesser degrees of mucosal pathology (type 1/2). Clearly more information will accrue; meanwhile the remarks in this brief survey should provide a firm basis whereby clinician and scientist can meet, and together recognize and further dissect the modulatory effect of T lymphocytes on mucosal structure and function.     

FEEDBACK CONTROL OF A HEAT DIFFUSION SYSTEM WITH TIME-DEPENDENT SPATIAL DOMAIN

The problem of controlling the temperature distribution in a solid cylinder whose length varies with time and with one end in contact with a constant temperature medium is considered. This problem is motivated from that of controlling the temperature and thermal gradient inside a crystal pulled from a melt by the Czochralski method. Boundary feedback controls are derived by considering the time rate of change of a cost functional involving the deviations of both the solid temperature and its gradient from their desired values. The derived feedback controls consist of spatially distributed proportional-plus-rate and lag compensators and a non-linear feedback control involving the temperature gradient at the cylinder surface and the velocity of the spatial domain boundary. The resulting feedback-controlled system has the property that the cost functional along any motion decreases monotonically to zero with time. A numerical scheme for solving the partial differential equation of the feedback-controlled system is proposed. Typical numerical results on the dynamic behaviour of the feedback-controlled system obtained by means of the proposed scheme are presented.     

补碘对7～12岁轻度碘缺乏病儿童脑功能及生长、发育的影响

通过半年对３５名７～１２岁轻度碘缺乏病儿童进行补碘，并与同龄、同地的正常儿童和缺碘未补碘儿童进行比较，以观察补碘对儿童脑功能及生长发育的影响。结果发现：①补碘可使儿童碘营养状况恢复正常，尿碘值由（８３．２±３．５）μｇ／Ｌ上升到（１６２．２±１．６）μｇ／Ｌ，血清Ｔ４、ＦＴ４Ｉ和ｒＴ３：也与正常儿童一致而与未补碘儿童有显著性差异（Ｐ＜０．０５）．②轻度碘缺乏病儿童智商低于正常儿童（Ｐ＜０．０１），补碘在一定程度上改善其智商水平。③轻度碘缺乏病及补碘未能明显影响儿童的生长发育，可能与儿童总营养水平较差有关。     

Peak Endocardial Acceleration-Based Clinical Testing of the "BEST" DDDR Pacemaker

The peak endocardial acceleration (PEA, unit g) shows a near correlation with myocardial contractility during the isometric systolic contraction of the heart (dP/dtmax), with sympathetic activity and, thus, with physiological heart rate modulation. The (Biomechanical Endocardial Sorin Transducer (BEST) sensor is incorporated in the tip of a pacing lead and measures PEA directly near the myocardium. In an international study, the lead was implanted with the dual chamber pacemaker Living-1 (Sorin) in 105 patients. The behavior of the PEA signal was tested under conditions of physical and mental stress and during daily life activities by 24-hour recordings of PEA (PEA Holter) at 1 to 2 months and approximately 1 year after implantation. Implantation of the BEST lead was performed without complications in all patients. The sensor functioned properly in the short- and long-term in 98% of patients. Although PEA values differed from patient to patient, the values closely reflected the variations in sympathetic activity due to physical and mental stress in each patient. During exercise and during daily life activities a close correlation between PEA and heart rate was observed among patients with normal sinus rhythm. Peak endocardial acceleration allows a nearly physiological control of the pacing rate.