替牙(牙合)时期前牙反(牙合)矫治中弓丝弯制的探讨

目的　探讨在“2× 4”矫治技术中弓丝弯制的方法及原理。方法　替牙牙合时期前牙反牙合患者 2 4例 ,使用粗弓丝 ,在其弓丝上弯制各种曲形 ,并根据不同错牙合类型 ,处理各种曲与牙齿、带环关系 ,防止出现磨牙旋转移动等异常。结果　 2～ 6个月纠正反牙合 ,2 4例替牙牙合时期反牙合患者得以早期矫治。结论　本方法矫治时间短 ,效果明显 ,操作简单 ,能够达到较为理想的矫治效果     

持续压力超负荷对兔左心室细胞凋亡的影响

OBJECTIVE: To study the effect of chronic pressure overload on the apoptosis of the left ventricle myocytes in rabbits. METHODS: Rabbit models of chronic pressure overload-induced heart failure were prepared in which dynamic changes of apoptotic myocytes in the left ventricle were observed by way of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. RESULTS: Only a few apoptotic cells was observed in the sham-operated group, while in the experimental group, the apoptotic left ventricle myocytes significantly increased after operation, presenting a peak level between day 3 and day 7. Seven days after the operation, the apoptotic myocytes began to decrease and till day 14, the apoptotic cell number had been smaller than that measured on day 1. When signs of heart failure set in, the apoptotic myocytes were again increased (P<0.001). CONCLUSION: During chronic pressure overload, myocyte apoptosis in the left ventricle is elevated at the early stages and undulates subsequently, with the peak occurring before hypertrophy is obvious.     

Point mutation in the parkin gene on patients with Parkinson’s disease

Summary To investigate the distribution of possible novel mutations from parkin gene in variant subset of patients with Parkinson’s disease (PD) in China and explore whether parkin gene plays an important role in the pathogenesis of PD, 70 patients were divided into early-onset group and late-onset group; 70 healthy subjects were included as controls. Genomic DNA from 70 normal controls and from those of PD patients were extracted from peripheral blood leukocytes by using standard procedures. Mutations of parkin gene (exon 1–12) in all the subjects were screened by PCR-single strand conformation polymorphism (SSCP), and further sequencing was performed in the samples with abnormal SSCP results, in order to confirm the mutation and its location. A new missense mutation Gly284Arg in a patient and 3 abnormal bands in SSCP electrophoresis from samples of another 3 patients were found. All the DNA variants were sourced from the samples of the patients with early-onset PD. It was concluded that Parkin point mutation also partially contributes to the development of early-onset Parkinson’s disease in Chinese. WANG Tao, male, born in 1961, Associate Professor This work was supported by grants from the key program of the special scientific project of Scientific & Technologic Agency of Hubei Province (Serial No. 2001AA308B01) and the Hygienic Research Project of Hygienic Agency of Hubei province (Serial No. WJ 01529).     

Early antenatal sonographic diagnosis of conjoined syncephalus-craniothoraco-omphalopagus twins. Case report.

The paper describes the prenatal ultrasonographic diagnosis of conjoined syncephalus-craniothoraco-omphalopagus twins at 13 weeks' gestation. The mother, after genetic counseling, decided to interrupt the pregnancy. The fetal karyotype, the maternal serum and amniotic fluid alpha-fetoprotein levels were normal. The diagnosis was confirmed by pathologic examination of the fetus after termination of pregnancy.     

Post-translational processing of thyrotropin-releasing hormone precursor in rat brain: identification of 3 novel peptides derived from pro TRH

The sequence of rat hypothalamic pro-thyrotropin releasing hormone, deduced by sequencing of cDNA, in addition to 5 TRH progenitor genitor sequences contains leader, trailer and 4 intervening sequences separated by paired basic amino acid sequences. We have developed radioimmunoassays to synthetic peptides corresponding to portions of these cryptic proTRH sequences and have used these assays to identify and partially characterize proTRH peptides, distinct from TRH, in extracts of rat brain. Two of these peptides correspond closely in size to one intervening sequence and the car☐y-terminal sequence of proTRH. Three other peptides correspond to the intact amino-terminal leader sequence and two peptides formed by a further cleavage of the leader sequence at an internal paired basic amino acid sequence.     

内分泌激素与脑血管疾病的相关性研究进展

众多的激素参与脑血管疾病的病理过程 ,与其发展预后密切相关。内分泌激素的研究为脑血管疾病的预后和治疗提供广阔的前景 ,如果能进一步研究脑血管疾病和激素的关系 ,必然会使脑血管疾病预后的判断和治疗跨上一个新台阶 ,为激素受体拮抗剂的临床应用开拓新天地。     

急性苯中毒对小鼠末梢血象和骨髓细胞构成的影响

取３２只２～３个月的ＢＡＬＢ／Ｃ小白鼠，随机分为４组，每组８只，第１组为对照组，其余３个组为实验组，实验组小白鼠左腿皮下注射苯０．３ｍｌ（１５ｍｌ／ｋｇ体重）．注射后分别于２４ｈ，４８ｈ，７２ｈ脱颈处死。观察中毒前、后末梢血象、骨髓细胞、骨髓细胞构成的变化。结果表明，苯中毒时骨髓变化先于末梢血象的变化，骨髓的病变为造血细胞变性、坏死，大量毛细血管扩张、充血，骨髓细胞构成降低，而且骨髓细胞构成中细胞成分降低早于外周血粒细胞减少。