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91.
92.
The absolute granulocyte count (AGC) in 125 blood samples from patients with total white blood cell counts of less than 1,000/microliter was estimated using three different methods, which were then compared for efficiency and accuracy. The three methods were 25 cell differential counts using Wright's-stained blood smears, granulocyte percentage estimates from WBC counting chambers, and combined narrow- and wide-angle light-scatter characteristics determined on a flow cytometer. A survey of clinical laboratories at University Hospital Cancer Centers revealed that the smear differential was the most-often-used method in those laboratories even when less than 25 cells could be counted. Consequently the data obtained from the counting chamber and flow cytometer methods were compared to the smear differential "standard" using linear regression, and outliers were identified. There was good correlation between AGC determined by smear differential and WBC counting chamber (correlation coefficient .911) and excellent correlation between the AGC determined by smear differential and the flow cytometer method (correlation coefficient .970). The flow cytometer method used in this investigation required minimal specimen preparation, and test results were available at a rate of 60 seconds/sample. The ease of sample preparation, speed, and statistical reliability of test results makes the flow cytometer an attractive alternate method of determining granulocyte counts on leukopenic patients as compared to the stained blood smear differential. 相似文献
93.
The innervation of four functionally different muscles (subalar, remotor 1, remotor 2, pleuroalar), all served by the same nerve branch, was studied in both winged segments of the locust, Locusta migratoria. Several anatomical techniques were applied: With the cobalt backfill and silver intensification technique four cell types (motoneurone, dorsal unpaired median neurone, common inhibitory neurone, and small median neurone) were demonstrated. Serial sections enabled the morphology of the motoneurones to be described in more detail and in respect to a possible functional organization of the arborizations. A differential staining technique allowed us to stain various neurones in different colours in the same preparation. With this technique the anatomy of both the "rostral" and the "caudal" subalar motoneurones could be described in parallel, thus avoiding errors in comparison due to possible individual variations from preparation to preparation. Axon counts in the peripheral nerve branch enabled us to compile a list of the total innervation for each muscle. Results from other orthopterans are integrated and whether differences in the dendritic fields might be of functional significance is discussed. 相似文献
94.
Rainhardt Osieka R. Pannenbäcker Carl Gottfried Schmidt 《Investigational new drugs》1984,2(2):161-168
Summary Cyclophosphamide (CPA) is widely used against leukemic and lymphoproliferative diseases, but in vitro studies on response to this agent so far have been limited to instable derivatives with poor galenic properties. ASTA Z 7557 is a newly synthesized activated cyclophosphamide that circumvents the need for hepatic activation and has good stability. The critical cytotoxic lesions after exposure to bifunctional alkylating agents presumably are DNA interstrand crosslinks (ISC). We have, therefore, examined the formation and apparent removal of ISC after in vitro treatment with ASTA Z 7557 by use of the highly sensitive alkaline elution technique. Survival of murine L1210 cells was determined after 1 hour in vitro exposure with a D 37 value of 5.7 g/ml (from the initial shoulder part of the survival curve) and a Do value of 1.5 g/ml (from the exponential part of the curve). Previous labelling of L1210 cells by 125IUdR simplified the alkaline elution procedure but there was some cytotoxicity of the radiochemical itself with a reduction of cloning efficiency from 77% to 61 %. The maximum of ISC was observed at 6 h after initiation of treatment with much of the damage apparently removed at 24 h. The simultaneous presence of DNA single strand breaks (SSB), however, confounds the analysis of DNA damage at 24 h and early cytolysis and unaided death of human lymphocytes often preclude the analysis of macromolecular damage at this time. Human peripheral blood cells isolated from patients with leukemic or lymphoproliferative diseases showed a remarkable heterogeneity with regard to the formation of ISC at 3 h. Thus, analysis of macromolecular damage may become an additional prognostic factor for response to CPA beyond the morphologic classification of these diseases. 相似文献
95.
Wojciech Czogaa Magorzata Czogaa Wojciech Strojny Gracjan Wtor Pawe Wokow Magorzata Wjcik Mirosaw Bik Multanowski Przemysaw Tomasik Andrzej Wdrychowicz Wojciech Kowalczyk Karol Miklusiak Agnieszka azarczyk Przemysaw Haubiec Szymon Skocze 《Nutrients》2021,13(5)
The occurrence of childhood obesity is influenced by both genetic and epigenetic factors. FTO (FTO alpha-ketoglutarate dependent dioxygenase) is a gene of well-established connection with adiposity, while a protooncogene PLAG1 (PLAG1 zinc finger) has been only recently linked to this condition. We performed a cross-sectional study on a cohort of 16 obese (aged 6.6–17.7) and 10 healthy (aged 11.4–16.9) children. The aim was to evaluate the relationship between methylation and expression of the aforementioned genes and the presence of obesity as well as alterations in anthropometric measurements (including waist circumference (WC), body fat (BF_kg) and body fat percent (BF_%)), metabolic parameters (lipid profile, blood glucose and insulin levels, presence of insulin resistance) and blood pressure. Expression and methylation were measured in peripheral blood mononuclear cells using a microarray technique and a method based on restriction enzymes, respectively. Multiple regression models were constructed to adjust for the possible influence of age and sex on the investigated associations. We showed significantly increased expression of the FTO gene in obese children and in patients with documented insulin resistance. Higher FTO expression was also associated with an increase in WC, BF_kg, and BF_% as well as higher fasting concentration of free fatty acids (FFA). FTO methylation correlated positively with WC and BF_kg. Increase in PLAG1 expression was associated with higher BF%. Our results indicate that the FTO gene is likely to play an important role in the development of childhood adiposity together with coexisting impairment of glucose-lipid metabolism. 相似文献
96.
目的 探讨多药耐药基因(MDR1基因)在人胃癌组织中的表达及其与临床病理的关系。方法 采用逆转录-多聚酶链反应(RT-PCR)法检测了215例手术切除的进展期胃癌组织中的MDR1基因的表达。实验数据采用SAS软件中的χ^2检验和Fisher’s exact P做统计学处理。结果 MDRI基因的阳性率为31.63%(68/215),与年龄、性别、组织学类型、分化程度、淋巴结转移、Borromann分型及TNM分期等无关,但在分化差的肿瘤中有增高趋势,如黏液腺癌及印戒细胞癌中达41.67%及50.00%。结论 化疗前胃癌组织中MDRI基因即存在较高的表达率,这为选用化疗药物和MDR逆转剂提供了参考指标,但不能作为制定化疗方案的唯一指标。 相似文献
97.
端粒酶及nm23的表达与胃腺癌预后的关系探讨 总被引:1,自引:0,他引:1
目的 :探讨端粒酶和nm2 3癌基因蛋白表达与胃癌根治术后复发及预后的关系。方法 :采用端粒酶原位分子杂交技术及免疫组化S P法分别对 4 5例原发性胃腺癌组织中端粒酶的活性及nm2 3进行检测 ,并结合内镜及随访资料进行分析。结果 :胃腺癌端粒酶阳性表达率及nm2 3低表达率在有淋巴结转移组显著高于无淋巴结转移组 ;在术后 5年内复发者中显著高于无复发者。虽然随着胃腺癌分化程度的降低及浸润深度的增加 ,端粒酶活性及nm2 3低表达呈增强趋势 ,但其差异无统计学意义。结论 :胃腺癌组织中端粒酶的活性表达及nm2 3的低表达与淋巴结转移及术后复发显著相关 ,两者的表达变化对判断胃癌术后复发及预后判断有重要临床意义 相似文献
98.
Leslie Sim PhD Carol B. Peterson PhD 《The International journal of eating disorders》2021,54(11):2046-2056
Differential susceptibility, a reconceptualization of the diathesis-stress model of psychopathology, describes gene–environment interactions that reflect individual differences in responsiveness to environmental influences, both detrimental and beneficial. This model has been described metaphorically by the classification of orchids, which thrive under optimal care but wither under adverse conditions, and dandelions, which weather broad environmental circumstances but are less responsive to careful cultivation. Etiological research in the field of eating disorders has largely focused on the identification of specific behavioral phenotypes, temperamental traits, genotypes and neurobiological processes that confer risk. In this article, we propose that these putative vulnerability factors represent phenotypes and endophenotypes of a genetic predisposition towards environmental sensitivity. We assert that this sensitivity not only transmits eating disorder risk but also confers resilience, depending on the circumstances. In particular, we propose that differential susceptibility can be used as a framework to organize disparate temperamental and neurobiological findings and their complex interplay with various developmental, environmental and sociocultural influences to increase eating disorder risk and treatment responsiveness. Finally, we assert that viewed through the lens of differential susceptibility, sensitivity can be leveraged to refine our interventions and develop novel treatment and prevention strategies to support favorable outcomes for individuals with eating disorders. 相似文献
99.
100.
目的研究喉癌中表皮生长因子受体(EGFR)基因的扩增、表达,探讨其在喉癌发生、发展中的作用及临床意义。方法采用差异PCR(differential PCR)方法检测40例喉鳞状细胞癌及配对癌旁正常组织中EGFR基因的扩增(即基因拷贝数增加);应用RT-PCR方法检测EGFR mRNA水平;应用SPSS13.0软件对数据进行统计学分析。结果喉癌组织中有13例(占32.5%)EGFR基因拷贝数增加,癌旁对照组中则未检测到(χ2=15.537,P<0.005);喉癌组织中EGFR mRNA平均积分光密度为872.356±62.340,癌旁对照组为346.425±57.380(t=5.959,P<0.001);喉癌组织分化程度越低,病理分期越晚,EGFR基因扩增和mRNA表达水平越高(P<0.05)。结论喉癌中EGFR基因在DNA水平上的扩增是EGFR mRNA过表达的原因之一,EGFR的扩增和过表达在喉癌的发生、进展中发挥一定作用。 相似文献