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131.
132.
清除骨髓中癌细胞的磁性微球研究 II.聚苯乙烯磁性微球的研制 总被引:1,自引:0,他引:1
为制备能用于清除骨髓中癌细胞的磁性微球,首先合成了单分散、大粒径的多孔聚苯乙烯交联微球,借助微球多孔结构对其进行磁化。探讨了影响磁化效果的主要因素。为使其与单抗连接紧密,在微球表面聚合了一层聚丙烯醛膜,使其表面带上易与单抗反应的醛基。同时测定了所制微球的磁响应性。X-射线衍射证明磁性物质为γ-Fe2O3。 相似文献
133.
JC Sutton PhD PJ Standen PhD WA Wallace FRCS 《International journal of clinical practice》1994,48(2):63-66
SUMMARY Many previous studies of reported patient accidents in hospital used the accident report forms as the only data source, without questioning their reliability and despite 80% of the accidents being unwitnessed. This paper reports on three studies using data from patient interviews, staff questionnaires, medical and nursing notes and the accident report forms. The studies confirm that falls amongst elderly patients are the most common type of patient accident. However, patients' and staff's versions of the event often differed widely. Accident reports are stated to be required for legal purposes, but they were often incomplete and unreliable. Patient accidents and safety are too important to remain marginalised to mere compliance with out-of-date regulations. A new, ‘slim-line‘, more accurate but less time-consuming patient accident reporting system should be developed, for which improvement in patient safety is the main aim and legal considerations the secondary aim. 相似文献
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Standard auditory evoked potentials (AEP) were recorded in 50 schizophrenic patients and 47 normal controls. All patients were rated on the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Negative Symptoms (SANS), the Scale for the Assessment of Positive Symptoms (SAPS), and the Positive and Negative Syndrome Scale (PANSS), and were classified in three groups (positive-type [n = 10], negative-type [n = 23]and mixed-type [n = 17]patients) according to the normative criteria suggested by Kay. The mean latencies of AEP components (N1, P2, N2) and mean peak-to-peak amplitudes (N1P2, P2N2) did not correlate with age, duration of illness, length of hospitalisation or neuroleptic dosage. The evoked response did not differ between the three groups of patients (positive, negative and mixed). There was only a trend (P = 0.075) to a longer N1 latency in the negative-type group and a shorter one in the positive-type group than in the mixed-type and the control groups. The latency of N1 component correlated significantly with negative symptoms of schizophrenia (SANS scores). This correlation was related to the severity of a depressive dimension of the disorder reflected by the “depressive factor” of BPRS or “affective flattening” and “avolition” subscales of SANS. 相似文献
138.
JM Fernández Vozmediano JC Armario Hita 《Journal of the European Academy of Dermatology and Venereology》2005,19(1):42-46
INTRODUCTION: Allergic contact dermatitis (ACD) is equally as likely in infancy as in adulthood, and represents 20% of all cases of dermatitis in children. Its true prevalence and incidence are, however, unknown. MATERIALS AND METHODS: We have conducted a retrospective study over 10 years of a group of patients aged 15 years or less, with clinical suspicion of ACD. Patch tests were performed in accordance with the standards of the GEIDC. RESULTS: The study covered 96 patients with a mean age of 10.57+/-0.67 years. The zones most frequently affected by eczemas were those of diffuse distribution (28% of patients) and of the hands (27%). We found at least one positive response in 52% of the cases. The most frequent allergens were thiomersal (21%), mercury (19%) and nickel (18%). We have found a statistically significant association between age of less than 15 years and positive response to thiomersal [P<0.01; OR: 8.5 with confidence interval (CI) 95%: 5.08相似文献
139.
Kronenberg G Wang LP Geraerts M Babu H Synowitz M Vicens P Lutsch G Glass R Yamaguchi M Baekelandt V Debyser Z Kettenmann H Kempermann G 《Brain structure & function》2007,212(1):19-35
Since reports that precursor cells in the adult subventricular zone (SVZ) contribute to regenerative neuro- and gliogenesis
in CA1, we wondered whether a similar route of migration might also exist under physiological conditions. Permanent labeling
of SVZ precursor cells with a lentiviral vector for green fluorescent protein did not reveal any migration from the SVZ into
CA1 in the intact murine brain. However, in a nestin-GFP reporter mouse we found proliferating cells within the corpus callosum/alveus
region expressing nestin and glial fibrillary acidic protein similar to precursor cells in the neighboring neurogenic region
of the adult dentate gyrus. Within 3 weeks of BrdU administration, BrdU-positive nestin-GFP-expressing protoplasmic astrocytes
emerged in CA1. Similar to precursor cells isolated from the dentate gyrus and the SVZ, nestin-GFP-expressing cells from corpus
callosum/alveus were self-renewing and multipotent in vitro, whereas cells isolated from CA1 were not. Nestin-GFP-expressing
cells in CA1 differentiated into postmitotic astrocytes characterized by S100β expression. No new neurons were found in CA1.
The number of nestin-GFP-expressing astrocytes in CA1 was increased by environmental enrichment. We conclude that astrogenesis
in CA1 is influenced by environmental conditions. However, SVZ precursor cells do not contribute to physiological cellular
plasticity in CA1. 相似文献
140.
Detection of fetal red cells in fetomaternal hemorrhage using a fetal hemoglobin monoclonal antibody by flow cytometry 总被引:4,自引:0,他引:4
BACKGROUND: The laboratory determination of the level of fetal cells in maternal circulation remains an important support in the obstetrical management of women with suspected uterine trauma and in the proper dose administration of anti-D for prevention of Rh hemolytic disease of the newborn. Limitations in the sensitivity and precision of the widely used manual Kleihauer-Betke test have prompted an increased utilization of flow cytometric methods for fetal cell detection in maternal blood samples. STUDY DESIGN AND METHODS: Murine monoclonal antibodies directed against fetal hemoglobin (HbF) were developed, conjugated to fluorescein isothiocyanate, and used in a multiparametric flow cytometric assay developed for the quantitation of fetal red cells. A rapid intracellular staining method using brief glutaraldehyde fixation and Triton X-100 permeabilization prior to monoclonal antibody incubation was developed, along with optimization of the flow cytometric analysis protocol for the analysis of 50,000 cells. The performance of the assay was assessed for linearity and precision and correlated with the Kleihauer-Betke acid elution method. RESULTS: The anti-HbF flow cytometric method showed good correlation with the Kleihauer-Betke method (r2 = 0.86) and superior precision with a CV < 15 percent for blood samples with > 0.1 percent fetal cells. Analysis of 150 blood samples from nonpregnant adults, including individuals with elevated HbF due to hemoglobinopathies and hereditary persistence of HbF, gave a mean value of 0.02 percent fetal cells, and all results were less than 0.1 percent. CONCLUSIONS: The anti-HbF flow cytometric method for detection of fetal cells offers a simple, reliable, and more precise alternative to the Kleihauer-Betke manual technique for the assessment of fetomaternal hemorrhage. The method has additional potential applications for the study of HbF levels or frequency of adult red cells with low levels of HbF (F cells) in individuals with hemoglobinopathies. 相似文献