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Biomedical subjects

S H Yang

Publications and source records attributed to S H Yang.

At least 127 records · Page 7Linked to original sources
PubMed1991

Cytogenetic study of twenty-two intracranial tumors.

G-banded chromosomal analysis was performed on primary cultures of 22 intracranial tumors, including eight astrocytomas, nine meningiomas, two dermoid cysts, one acoustic neuroma, one pineal teratoma and one eosinophilic granuloma. One or more chromosomally abnormal clones were observed in 6 (75%) gliomas and 5 (56%) meningiomas. There was no chromosomal abnormality found in one of the dermoid cysts, the acoustic neuroma or the eosinophilic granuloma. A teratoma and a grade IV glioma had heterogeneous hyperdiploid karyotypes. Furthermore, astrocytomas displayed nonrandom loss of chromosomes #19, #21, #22 and Y. In meningiomas, characteristic changes involving chromosome 22 were found in 5 tumors. One meningioma had a ring chromosome in addition to chromosomal loss. With our culture and harvesting techniques, cytogenetic studies can be successfully performed on nearly all intracranial tumor explants, including those derived from small biopsy specimens. Also, in our study, specific nonrandom chromosomal anomalies were found.

Astrocytoma↗
PubMed1990

Hemorrhagic fever with renal syndrome. Separation of human peripheral blood T and B cells and detection of viral antigen.

In this study, total blood lymphocytes were prepared from patients with hemorrhagic fever with renal syndrome (HFRS) by a density gradient on Ficoll-Hypaque. T and B cells were then purified by passing the total lymphocytes over a nylon wool column. The purities of total lymphocytes, T cells and B cells were 97.8 +/- 2.3%, 91.6 +/- 4.5% and 74.2 +/- 12.1%, respectively. Also, after modification of cell fixation and smear drying, the number of cells were increased and the time needed for slide preparation was shortened. Detection of viral antigen by immunofluorescence assay using monoclonal antibodies to Hantavirus (HTNV) showed that the total lymphocytes. T cells and B cells were infected by HTNV during the early stages of HFRS and no specific fluorescence was seen in the cells from the late diuretic phase to convalescent phase. The results suggest that virus replication in blood lymphocytes may partly contribute in the early stages to the impairment of cell immune response and in vivo spread of HTNV to its target sites.

Antigens, Viral↗
PubMed1989

[Preparative separation of borneol and isoborneol in bingpian by dry-column chromatography].

Borneol (I) and isoborneol (II) in synthetic Bingpian are separated by means of dry-column chromatography (DCC). The sample mixed with a small amount of adsorbent is transferred to the top of the column (50 x 4 cm i.d.) packed with silica gel (200 mesh) and developed with petroleum ether-ethyl acetate-chloroform (20:2: 6) until the solvent has spread from the top to the bottom of column. The zones of I and II can be located by the corresponding Rf of TLC. They are then eluted separately with absolute alcohol. After the concentration of the eluent by vacuum distillation, the crystals of I and II are isolated from the residual solution on standing. The purities of I and II are tested with known specimens by TLC.

Camphanes↗
PubMed1989

[Evaluation of 3 chest leads CM5, CC5, and CL5 and factors which influence the results].

In recent few years, many authors had discussed the possibilities of using bipolar precordial leads to replace lead V5 in diagnosing anterior wall myocardial ischemia. But there still remains some problems to be solved: (1) Are there any difference between bipolar precordial leads and lead V5 in wave forms? (2) What kind of factors influence the ST deviation? 36 patients were studied by comparing unipolar lead V5 with respect to three different bipolar chest leads CM5, CC5, CL5 both in lying and sitting positions. We found that: (1) The differences is least significant between bipolar CC5 and lead V5 while it is most significant between bipolar lead CM5 and lead V5. (2) The deviation of ST segment in bipolar leads is affected both by potential at negative electrode as well as potential at positive electrode. Statistical analysis revealed that ST segment is positively related to the potential on positive electrode and negatively related to the potential on negative electrode. For this reason, therefore, in the view point of most comparable ST deviation with lead V5 for monitoring of myocardial ischemia, it is advisable to locate the negative electrode at the site on chest with least potential. Usually we place the negative electrode on V6R to compose a bipolar lead CC5.

Coronary Disease↗
PubMed1985

Improvement in hearing among otherwise normal schoolchildren in iodine-deficient areas of Guizhou, China, following use of iodized salt.

According to a survey in Guizhou province of China, the average hearing level of otherwise normal schoolchildren in an area of endemic iodine-deficient goitre and cretinism was significantly poorer than in a non-endemic control area. After iodine prophylaxis for three years, audiometric tests showed that the average hearing level had improved and approached that of the non-endemic controls. In addition, mean values for thyroid function tests were restored to within the normal range. It is suggested that the most likely cause of the poorer hearing level among the ostensibly normal schoolchildren in endemic areas is subclinical hypothyroidism due to prolonged severe iodine deficiency.

Audiometry↗