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971.
Illana Gozes John Glowa Douglas E. Brenneman Susan K. McCune Eric Lee Heiner Westphal 《Journal of molecular neuroscience : MN》1993,4(3):185-193
The molecular mechanisms responsible for behavior are largely unknown. A state of the art model, paving the path from genes
to behavior, is offered by transgenic animals. Candidate molecules are classic neuropeptides, such as vasoactive intestinal
peptide (VIP). Transgenic mice harboring a chimeric VIP gene driven by the polyoma promoter were produced. Behavioral studies
revealed learning impairment and prolonged retardation in memory acquisition in the genetically altered animals. Furthermore,
reduced performance was observed when the male transgenic mice were tested for sexual activity in the presence of receptive
females. Surprisingly, radioimmunoassays showed an approx 20% decrease in the VIP content of the transgenic mice brains. To
directly assess genetically reduced VIP content as a cause for learning impairment, transgenic mice carrying diphtheria toxia-encoding
sequences driven by the rat VIP promoter were created. These animals had reduced brain VIP and exhibited deficiencies in learning
abilities, strongly supporting an important neurobiological function for VIP in vivo. 相似文献
972.
Diffuse Axonal Injury (DAI) is not Associated with Elevated Intracranial Pressure (ICP) 总被引:7,自引:0,他引:7
Summary
Objective. Traditionally, intracranial pressure (ICP) monitoring has been utilized in all patients with severe head injury (Glasgow
coma score of 3–8). Ventriculostomy placement, however, does carry a 4 to 10 percent complication rate consisting mostly of
hematoma and infection. The authors propose that a subgroup of patients presenting with severe head trauma and diffuse axonal
injury without associated mass lesion, do not need ICP monitoring. Additionally, the monitoring data from ICP, MAP, and CPP
for a comparison severe head injury group, and subgroups of DAI would be presented.
Materials and methods. Thirty-six patients sustaining blunt head trauma and fitting our strict clinical and radiographic diagnosis of DAI were enrolled
in our study. Inclusion criteria were severe head injury patients who did not regain consciousness after the initial impact,
and whose CT scan demonstrated characteristic punctate hemorrhages of <10 mm diameter at the greywhite junction, basal ganglia,
corpus callosum, upper brainstem, or a combination of the above. Patients with significant mass lesions and documented anoxia
were excluded. Their intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were compared to a control group of
36 consecutive patients with severe non-penetrating non-operative head injury, using the Analysis for Variance method.
Results. Eighteen (50.0%), six (16.7%), and twelve (33.3%) patients had types I, II, and III DAI, respectively. The admission Glasgow
Coma Score (GCS) was higher for types I and II than for type III DAI. ICP was monitored from 23 to 165 hours, with a mean
ICP for 36 patients of 11.70 mmHg (SEM=75) and a range from 4.3 to 17.3 mmHg. Of all ICP recordings, of which 89.7% (2421/2698)
were ≤20 mmHg. Average mean arterial pressure (MAP) was 96.08 mmHg (SEM=1.69), and 94.6% (2038/2154) of all MAP readings were
greater than 80 mmHg. Average cerebral perfusion pressure (CPP) was 85.16 mmHg (SEM=1.68), and 90.1% (1941/2154) of all CPP
readings were greater than 70 mmHg. This is compared to the control group mean ICP, MAP, and CPP of 16.84 mmHg (p=0.000021),
92.80 mmHg (p=0.18), and 76.49 mmHg (p=0.0012). No treatment for sustained elevated ICP>20 mmHg was needed for DAI patients
except in two; one with extensive intraventricular and subarachnoid hemorrhage who developed communicating hydrocephalus,
and another with ventriculitis requiring intrathecal and intravenous antibiotic treatments. Two complications, one from a
catheter tract hematoma, and another with Staph epidermidis ventriculitis, were encountered.
All patients, except type III DAI, generally demonstrated marked clinical improvement with time. The outcome, as measured
by Glasgow Coma Score (GCS) and Glasgow Outcome Score (GOS) was similarly better with types I and II than type III DAI.
Conclusion. The authors conclude that ICP elevation in DAI patients without associated mass lesions is not as prevalent as other severe
head injured patients, therefore ICP monitoring may not be as critical. The presence of an ICP monitoring device may contribute
to increased morbidity. Of key importance, however, is an accurate clinical history and interpretation of the CT scan. 相似文献
973.
D. G. Kim C.-Y. Kim S. H. Paek D. S. Lee J.-K. Chung H.-W. Jung B.-K. Cho 《Acta neurochirurgica》1998,140(7):665-674
Summary
Background To determine its roles in the diagnosis and the systemic evaluation of metastatic brain tumours, whole-body positron emission
tomography (PET) using [18F]FDG was performed in 20 consecutive patients.
Methods
All patients were thought to be suffering or needing to be differentiated from metastatic brain tumours. Nine patients had
multiple brain lesions; six were older and showed a rim-enhancing lesion with surrounding oedema; seven had homogeneously
enhancing periventricular lesion(s) on computed tomography (CT) and/or magnetic resonance (MR) imaging, thought to be central
nervous system lymphomas. Two patients had skull mass(es) and two patients had a solid mass suspected to be, respectively,
a haemorrhagic metastasis and a metastatic malignant melanoma. All of them received whole-body [18F]FDG PET and conventional systemic work-up for metastasis in order to compare the results of the two methods.
Results
Metastatic brain tumours were diagnosed on whole-body [18F]FDG PET in eleven patients who had extracranial and intracranial hypermetabolic lesions. In nine of these, a conventional
work-up also detected primary lesions which on whole-body [18F]FDG PET were seen to be hypermetabolic foci. Systemic lymph node metastases were detected by whole-body [18F]FDG PET only in two patients and histological diagnosis was possible by biopsy of lymph nodes rather than of brain lesions.
In the remaining nine patients who had only intracranial hypermetabolic foci, histological diagnosis was made by craniotomy
or stereotactic biopsy. It was confirmed that seven of nine patients were suffering from a primary brain tumour and two from
metastatic carcinoma. None of the nine showed evidence of systemic cancer on conventional work-up. Histological diagnoses
of the primary brain tumours were four cases of primary central nervous system lymphoma and one each of multifocal glioblastoma,
Ewing's sarcoma, and cavernous angioma.
Patients felt no discomfort during the whole-body [18F]FDG PET procedure and there were no complications. The false negative rate in [18F]FDG PET and in conventional work-up was 15.4% and 30.7% respectively. There were no false positives on either [18F]FDG PET or conventional work-up.
Conclusion
It is suggested that whole-body [18F]FDG PET is a safe, reliable, and convenient method for the diagnosis and systemic evaluation of patients thought to be suffering
or needing to be differentiated from a metastatic brain tumour. 相似文献
974.
975.
三种去神经法对清醒大鼠动脉压力感受性反射功能的影响 总被引:3,自引:0,他引:3
目的:测定急、慢性去主动脉神经(AD)、去颈动脉窦神经(SD)、同时去主动脉和窦神经(SAD)后大鼠动脉压力感受性反射对血压控制(ABR-BP)和心动周期控制(ABR-HP)的影响。方法:测定ABR-BP采用阻断动脉压力感受性反射传出通路前后,比较机体对去氧肾上腺素升压反应面积差异的方法,所得数值与改良的Smyth方法测定的ABR-HP值进行比较。结果:(1)大鼠SAD后ABR-HP为零,且代偿不明显;而ABR-BP约为30%,且代偿明显;(2)SD后ABR-BP与ABR-HP无显著差异,而AD和SAD后ABR-BP的作用显著大于ABR-HP的作用。结论:(1)大鼠的ABR-HP传入冲动全部来自于主动脉弓和颈动脉窦的压力感受器,而ABR-BP传入冲动大部分来自于这两处的感受器;(2)主动脉神经和窦神经感受传入在ABR-BP中的作用是相当的,并有明显的相互代偿;而在ABR-HP中,主动脉神经的作用比窦神经重要,其代偿能力也比窦神经显著。 相似文献
976.
A new cycloartane glycoside (1) was isolated from the aerial part ofThalictrum uchiyamai Nakai (Ranunculaceae). On the basis of chemical and physicochemical evidence, the aglycone structure of this compound was characterized as 16,25-dihydroxy-3,24-diacetoxy-9, 19-cycloartane-29-oic acid, a new derivative of cycloartane triterpene. Also, the oligosaccharide moiety of this glycoside were determined as 29-O-α-L-rhanmnopyranosyl-(1→2)-[β-D-xylofuranosyl-(1→6)]-β-D-glucopyranosy by application of HMBC technique. Consequently, the structure of compound 1 was elucidated as 29-O-α-L-rhanmnopyranosyl-(1→2)-[β-D-xylofuranosyl-(1→6)]-β-D-glucopyranosyl-16, 25-dihydroxy-3,24-diacetoxy-9,19-cycloartane-29-oic acid ester. 相似文献
977.
A 9-month-old male infant had generalized diffuse blue-gray pigmentation over most of his body, sparing the scalp, face, neck, palms, soles, periumbilical area, genital area, and nipples. Within the lesion, there were several conspicuous macules of considerably darker hue. Histologic examination revealed numerous dermal melanocytes. By 16 months of age, the child's blue-gray pigmentation had decreased substantially. 相似文献
978.
房室间隔缺损的形态学诊断——二维超声心动图与心血管造影,手术的比较 总被引:2,自引:1,他引:1
为了评估二维超声心动图(2DE)对房室间隔缺损(AVSD)的诊断和手术方法选择价值,对87例AVSD的2DE,心血管造影及手术结果进行回顾对照研究,病例年龄自3月至11月(平均3.9岁)。部分型AVSD46例,过渡型12例,完全型29例(A型21例,B型4例,C型4例)2DE诊断与手术诊断符合率在部分型AVSD中为97%,在过渡型及完全型AVSD中为84%,2DE诊断与手术诊断不符合大多为过渡型与 相似文献
979.
980.