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Biomedical subjects

J Guo

Publications and source records attributed to J Guo.

At least 451 records · Page 25Linked to original sources
PubMed1990

The establishment of rat hybridoma cell lines secreting McAb against strains of potato virus Y and analysis of its stability.

The rat splenocytes immunized with potato virus Y (PVYn) and ratmyeloma (IR983) were fused by PEG (M. W.1450). Three kinds of stable hybridoma cell lines secreting specific monoclonal antibodies (McAbs) were derived. One kind of the cell lines producing McAbs reacts to PVYn specifically. Another reacts to PVYo specifically. The third one reacts to both of the two strains. Tested by the methods of sandwich-ELISA and indirect-ELISA, all kinds of McAbs did not react to seven plant viruses: tobacco mosaic (TMV), cucumber mosaic (CMV), tobacco tech (TEV), alfalfa mosaic (AMV), turnip mosaic (TuMV), potato leaf roll (PLRV), potato virus X (PVX). The biological properties of the hybridoma cell lines and the McAbs were tested.

Animals↗
PubMed1990

Surgical considerations of re-do valve replacement.

Between August 1976 and May 1988, 43 patients had their heart valve prostheses replaced. The total mortality was as high as 25.6%, but the operative mortality was reduced to 6.25% in the last 16 cases. The indications, main risk factors and surgical techniques are discussed.

Adult↗
PubMed1989

Modification of a model for cerebral ischemia in the cat: a new method to occlude the middle cerebral artery.

A modified method of occluding the middle cerebral artery (MCA) by inserting a tiny copper wire into the lumen of the vessel to make a model for cerebral ischemia in the cat is described. Of 22 rats, 4 were controls and the remaining 18 were divided into two groups. Bipolar electrocoagulation was used in 9 cats and copper wire insertion was used in the other 9 to occlude the MCA through a transorbital approach. Two cats died after surgery and were excluded from this study. Of the 16 cats in two experimental groups, 13 of 14 showed hemiplegia and the other 2 were killed under anesthesia. Typical ischemic changes can be seen in the territory of the occluded MCA. Increased water content and decreased amplitude of somatosensory evoked potentials can be found in the ischemic hemisphere. Histochemical fluorescence study demonstrated that the sympathetic nerve fibers normally existing on the MCA can be completely destroyed by electrocoagulation but may remain intact with the copper wire method. This new method may have less influence on the vascular regulative function of the autonomic nervous system and be more similar to the pathological changes of cerebral infarction in man. We think our method can be useful for further research in cerebral ischemic disease and the regulative effects of the nervous system on brain vessels.

Animals↗
PubMed1989

Establishment of hybridoma cell lines secreting MCAs against potato virus X and determination of their physical and chemical characteristics.

Splenocytes from BALB/c mouse immunized with potato virus X (PVX) and myeloma cells (SP/2) were fused. After cloning and three screening cycles, three hybridoma cell lines secreting strain-specific monoclonal antibodies (MCAs) against PVX were obtained. These cell lines were stable for 20 generations and after storage in frozen form (in liquid nitrogen) for one year. The chromosome numbers of the three hybridoma cell lines clustered in the 92-102 range. The MCAs all belonged to the IgG3 immunoglobulin subclass. The medium supernatant antibody titer detected by indirect ELISA was 1:320-1:640. The mouse ascites antibody titer was 1:102,400-1:204,800, which was more than 300 times the rabbit antiserum titer (1:320). The MCAs had a neutralizing effect on the antigen, with neutralization titer of 1:10(2). There were no apparent changes in antibody activity after repeated freezing/thawing cycles, ammonium sulfate precipitation, or freeze-drying.

Ammonium Sulfate↗
PubMed1988

Low power CO2 laser-assisted microvascular anastomosis: an experimental study.

Low power CO2 laser-assisted microvascular anastomosis (LAMA) was used for saphenous artery autotransplantation in 40 rabbits. Eighty end-to-end anastomoses were performed by three methods (conventional interrupted suture, stay suture + laser, laser without stay suture). The long term patency rate in the three types of anastomosis is 93%, 93%, and 100%, respectively. The time needed for the laser procedure is half to one-third of that required for the interrupted suture method. The tensile strength of the bonding site can withstand up to 250 mm Hg of arterial pressure. We have demonstrated that the CO2 laser can be used in microvascular anastomosis with or without stay sutures. Aneurysm formation is a potential risk of LAMA. Accurate coaptation of the transected vessel, precise control of laser energy, and minimal area exposed to the laser beam are the key points for further improving anastomotic quality.

Anastomosis, Surgical↗
PubMed1988

[Statistical analysis of 1016 cases of nervous system tumors in different nationalities in Xinjiang].

1016 cases of tumors of the nervous system in different nationalities in Xinjiang were collected from biopsies and autopsies from 1956 to 1985. The distribution of these tumors by nationalities were 78.93% in Han, 11.02% in Uygur, 5.42% in Hazak and 3.65% in Hui, respectively. Of 1016 cases, 644 were intracranial tumors (63.38%) with a similar distribution as showed above (80.74%, 11.33%, 4.20%, and 3.27%, respectively). Glioma was predominant in the intracranial tumors (46.11%). It was showed that there was a high incidence of tumors of the nervous system in Han and Hazak as compared with the size of their populations. There were some differences in histologic type in different nationalities.

Adolescent↗