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131.
132.
Prospective observations on 442 consecutive samples have confirmed that pregnancies with CNS malformations are regularly associated with an abnormal cellular content of amniotic fluid. A crude semiquantitative test of the cell content can give valuable clinical information in relation to borderline amniotic fluid alpha-fetoprotein values, and help to detect false positive AFP's.  相似文献   
133.
BACKGROUND: INN 00835 is a synthetic pentapeptide with a potential for rapid onset of action as an antidepressant. Its efficacy was investigated in a pilot study in patients diagnosed with major depression. METHODS: Fifty two patients received either active drug - INN 00835 (26 patients) - or placebo (26 patients), subcutaneously at 0.2 mg/kg for 5 consecutive days. The patients were evaluated for an additional 4 weeks after treatment. Efficacy was evaluated by the following psychiatric rating scales: HAMD, MADRS, CSRS, CGI, and VAS. The effect of treatment was also evaluated by using a biochemical marker: changes in blood platelet serotonin (5HT) uptake rates in drug-treated patients compared to those in the placebo group. Plasma concentrations of INN 00835 were measured by LC/MS. RESULTS: Statistical analysis indicated a strong pharmacodynamic correlation between plasma drug concentrations at 1 h after dosing and the reduction in the severity of depression as measured by the psychiatric rating scales. A minimum effective plasma concentration (MEC) of INN 00835 was 5 ng/ml. Statistically significant differences in response to treatment (P<0.05) were found between patients with plasma concentrations above MEC and those in the placebo group, as well as between subjects with plasma concentrations above and below the MEC. The peak effect was observed after the 5-day treatment and the response to treatment persisted during the 4-week follow-up period. The change of 5HT uptake rates after treatment was significantly larger in the drug-treated group than in the placebo group. Limitations: This was a pilot study conducted in a relatively small population (52 patients) and the limited number of blood sampling times did not allow a comprehensive pharmacokinetic analysis. There was a relatively large placebo response. The results have to be confirmed in future, large scale studies. CONCLUSIONS: INN 00835 appears to be a promising drug for the treatment of major depression.  相似文献   
134.
Abstract The chemokine receptor CXCR4 is expressed by CD34 + hematopoietic stem/progenitor cells (HSC/HPC). Several investigators have suggested that expression of CXCR4 may be an important characteristic of HSC/HPC. We studied the dynamic expression of CXCR4 during growth factor-induced mobilization of HSC in a clinically relevant nonhuman primate model, Papio anubis (baboons). We evaluated whether CXCR4 expression in HSC/HPC varies during steady-state hematopoiesis as well as during growth factor-induced mobilization. Peripheral blood stem cells from 5 baboons were mobilized with growth factors. During mobilization, there was a consistent stepwise increase in the proportion of peripheral blood CD34 + cells that were CXCR4 -. The highest number of CD34 + CXCR4 - cells appeared in the peripheral blood at the same time as the maximum number of assayable colony-forming cells. The cloning efficiency of the CD34 + CXCR4 - population was 3-fold greater than that of CD34 + CXCR4 + cells, and the frequency of cobblestone area-forming cells was 6 times higher in the CD34 + CXCR4 - population in comparison to CD34 + CXCR4 + cells. Furthermore, the most quiescent CD34 + cells isolated on the basis of low Hoechst 33342 (Ho) and rhodamine 123 (Rho) staining (Ho Low /Rho Low ) were highly enriched in the CXCR4 Low/- cell population. Ex vivo incubation of mobilized peripheral blood CD34 + cells with growth factors for 40 hours resulted in increasing numbers of cells expressing CXCR4. Peripheral blood stem cell grafts containing CD34 + cells that consisted of predominantly CXCR4 - cells were able to rapidly engraft lethally irradiated baboons. Because the overwhelming number of CD34 + cells within the mobilized peripheral blood grafts were CXCR4 - and were capable of rescuing lethally irradiated baboons, it seems unlikely that the expression of CXCR4 in vitro is an absolute requirement for HSC homing and engraftment. In summary, our data suggest the dynamic nature of CXCR4 expression on CD34 + cells during growth factor-induced HSC/HPC mobilization. In addition, our data indicate that the lack of CXCR4 expression is possibly a characteristic of relatively more primitive HSC/HPC characterized by a higher proliferative capacity.  相似文献   
135.
A comparison of quantitative results expressed in hepatitis C virus (HCV) international units per milliliter, obtained from the VERSANT HCV RNA 3.0 (bDNA-3.0) assay, the QUANTIPLEX HCV RNA 2.0 (bDNA-2.0) assay, and the COBAS AMPLICOR HCV MONITOR version 2.0 (HCM-2.0) test was performed. A total of 168 patient specimens submitted to the Mayo Clinic Molecular Microbiology Laboratory for HCV quantification or HCV genotyping were studied. Of the specimens tested, 97, 88, and 79% yielded quantitative results within the dynamic range of the bDNA-3.0, bDNA-2.0, and HCM-2.0 assays, respectively. Overall, there was substantial agreement between the results generated by all three assays. A total of 15 out of 29 (52%) of the specimens determined to contain viral loads of <31,746 IU/ml by the bDNA-3.0 assay were categorized as containing viral loads within the range of 31,746 to 500,000 IU/ml by the bDNA-2.0 assay. Although substantial agreement was noted between the results generated by the bDNA-2.0 and bDNA-3.0 assays, a bias toward higher viral titer by the bDNA-2.0 assay was noted (P = 0.001). Likewise, although substantial agreement was noted between the results generated by the HCM-2.0 and bDNA-3.0 assays, a bias toward higher viral titer by the bDNA-3.0 assay was noted (P < or = 0.001). The discrepancy between the HCM-2.0 and bDNA-3.0 results was more pronounced when viral loads were >500,000 IU/ml and resulted in statistically significant differences (P < or = 0.001) in determining whether viral loads were above or below 800,000 IU/ml of HCV RNA, the proposed threshold value for tailoring the duration of combination therapy. The expression of quantitative values in HCV international units per milliliter was a strength of both the bDNA-3.0 and HCM-2.0 assays.  相似文献   
136.
Pre-B cell acute lymphoblastic leukaemia (cALL) commonly occurs in young patients and although successful conventional therapies are available (such as cytotoxic drugs and bone marrow transplantation) for a proportion of patients (approximately 30%) these are ultimately unsuccessful. Recurrence of disease is a result of the failure of the immune system to recognize these abnormal cells and down-regulation of crucial molecules required for cognate CD4(+) T cell recognition has been postulated as a means of immune escape. In this study we show that an embryonic kidney cell line (293 cells) transfected with CD154 (40 L.1) are capable of not only maintaining the viability of primary ALL cells in culture but can also up-regulate the expression of a number of crucial molecules involved in antigen recognition. We show that 40 L.1 cell stimulation of primary ALL cell cultures can not only enhance the allogeneic and autologous MLR response to such cells but will also induce CTL effectors which are capable of lysing wild-type autologous ALL cells. It is therefore conceivable that such an approach could be used to generate an active anti-tumour response in patients, following conventional therapy, reducing the incidence of recurrence.  相似文献   
137.
Cetirizine, a derivative of hydroxyzine, is a new compound with potent antihistaminic property without antiserotonin and anticholinergic activities. The effect of both a single dose (15 mg) and 7 days of treatment (15 mg twice daily) with cetirizine, a potent H1 antagonist on bronchoconstriction induced by histamine and leukotriene D4 (LTD4) has been examined in 10 patients with mild atopic asthma in a placebo-controlled, double-blind, crossover study. Cetirizine, after a single dose and 7 days of treatment with placebo, the geometric mean values of the provocative concentration of histamine causing a 20% fall in FEV1 (millimolars) were 1.60 (95% confidence interval, 0.82 to 3.11) and 1.67 (0.77 to 3.65), compared with 118.07 (77.22 to 180.54) (p less than 0.0001) and 53.16 (20.50 to 137.84) after cetirizine administration (p less than 0.0002). The mean inhibition after a single dose was twofold higher than after 1 week of treatment (p less than 0.05). After a single dose and 7 days of treatment with placebo, the geometric mean values of the provocative concentration of LTD4 causing a 20% fall in FEV1 (micromolars) were 2.26 (1.74 to 2.94) and 2.37 (1.77 to 3.17), compared with 3.90 (2.60 to 5.86) (p less than 0.05) and 3.21 (2.28 to 4.52) after cetirizine administration. This result suggests that cetirizine is a potent H1 antagonist in the human airways. Diminished activity after 1 week of treatment suggests subsensitivity of H1 receptors developing in human airways. The small protective effect after a single dose against LTD4-induced bronchoconstriction indicates a nonspecific rather than a specific receptor antagonism.  相似文献   
138.
Gene deletions in spinal muscular atrophy.   总被引:7,自引:0,他引:7       下载免费PDF全文
Two candidate genes (NAIP and SMN) have recently been reported for childhood onset spinal muscular atrophy (SMA). Although affected subjects show deletions of these genes, these deletions can lead to either a very mild or a severe phenotype. We have analysed a large number of clinically well defined patients, carriers, and normal controls to assess the frequency and extent of deletions encompassing both of these genes. A genotype analysis indicates that more extensive deletions are seen in the severe form of SMA than in the milder forms. In addition, 1 center dot 9% of phenotypically normal carriers are deleted for the NAIP gene; no carriers were deleted for the SMN gene. Our data suggest that deletions in both of these genes, using the currently available assays, are associated with both a severe and very mild phenotype.  相似文献   
139.
A 2-year-old male child with mosaicism for monosomy of chromosome 22 is described. He had moderate psychomotor retardation, generalised hypotonia, large ears, epicanthus, synophrys, and cutaneous syndactyly between all the fingers.  相似文献   
140.
BACKGROUND: Inhaled corticosteroids (ICS) are recommended therapy for persistent asthma, although side effects can limit appropriate use. Ciclesonide, a novel ICS, is activated in the lung, thereby reducing systemic activity and side effects. This 12-week, double-blind, randomized, parallel-group, placebo-controlled study evaluated the efficacy and safety of ciclesonide in adults with persistent asthma. METHODS: After a 2-week baseline period in which current ICS treatment was continued, 329 patients were randomized to receive ciclesonide 160 microg (n = 107) or 640 microg (n = 112) (ex-actuator doses, equivalent to 200 and 800 microg ex-valve, respectively), or placebo (n = 110) once daily in the morning. Efficacy was monitored by asthma symptom scores, rescue medication use, morning and evening peak expiratory flow (PEF) measurements, spirometry, and probability of study completion without experiencing lack of efficacy. RESULTS: Morning PEF remained stable with either ciclesonide dose but decreased with placebo; the differences were significant (P < 0.0001) for both ciclesonide doses vs placebo. The forced expiratory volume in 1 s and forced vital capacity decreased significantly with placebo (P < 0.005), but were unchanged with ciclesonide. Lack of efficacy was significantly greater for patients switched to placebo (63%) than it was for those treated with ciclesonide 160 microg (30%) (P < 0.0001 vs placebo) or ciclesonide 640 microg (31%) (P < 0.0001 vs placebo). There were no significant differences between the two tested doses of ciclesonide with respect to efficacy and safety. Serum and 24-h urine cortisol were unaffected by ciclesonide treatment. Both doses of ciclesonide were well tolerated with no cases of oral candidiasis. CONCLUSION: Ciclesonide (160 or 640 microg) once daily in the morning effectively maintains asthma control, does not affect cortisol levels, and has an adverse event profile comparable with placebo in adults with primarily mild to moderate asthma.  相似文献   
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