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Biomedical subjects

G Qi

Publications and source records attributed to G Qi.

28 records · Page 2Linked to original sources
PubMed1996

[Experimental studies of high frequency jet ventilation improved by enhancing expiratory turbulence].

OBJECTIVE: To improve the effect on CO2 elimination during high frequency jet ventilation by enhancing expiratory turbulence. METHODS: Nine healthy dogs with steam-induced type I respiratory failure were basically applied with high frequency jet ventilation (HFJV), and high frequency two-way jet ventilation (HFTJV), HFJV combined with thoracicoabdominal compression (HFJV+TAC), and HFJV combined with thoracicoabdominal compression-decompression (HFJV+ TACD) randomly for 30 min, respectively. The parameters were determined and the Reynolds numbers (NR) were calculated. RESULTS: Reynolds numbers were more than 3000 in all patterns, suggesting that the airflow was turbulent. Expiratory Na was higher. The NR of the latter three patterns was more significantly higher than that of HFJV (P < 0.01). CO2 elimination was 126, 111, 137 ml. min-1 in the latter three patterns, respectively and significant (P < 0.05) or very significant (P < 0.01) compared with 98.0 ml.min-1 in HFJV. Corresponding changes occurred in PaCO2. NO significant differences (P > 0.05) were observed in hemodynamic parameters. CONCLUSION: HFJV combined with inverse jet or thoracicoabdominal compression or decompression on expiratory phase could enhance expiratory turbulence and facilitate CO2 elimination in 9 dogs with steam-induced type I respiratory failure.

Animals↗
PubMed1996

[Surgical treatment of ventricular septal defect complicated by pulmonary hypertension at high altitude].

103 patients (52 males, 51 females) suffered from ventricular septal defect associated with pulmonary hypertension were operated on under sardiopulmonary bypass from 1981-1995 at high altitude. The age of the patients ranged from 2 to 29 years. The ratio of pulmonary systemic arterial pressure was more than 0.91 (0.91 to 1.21). The defects were closed by using dacron patch. The operative mortality was 4.8% among the survivals. 98 patients were followed up for a period from 3 months to 3 years (mean 2.4 years). Excellent results were observed in 93 patients, and good in 4. There was a late death. On account of the improvement in surgical technique, myocardial protection and postoperative care, the result of operation was improved markedly.

Adolescent↗
PubMed1996

[Influence of gypenoside on serum lipoprotein and atherosclerosis in hyperlipidaemia animals].

The result of the study indicates that gypenoside (GP, i.g.) can suppress the rise of serum cholesterol (CHO) and triglyceride (TRIG) in hyperlipidaemia mice and lower the content of CHO, TRIG and LDL in hyperlipidaemia quails. The study also shows that GP has a protective effect on diffuse lipoidosis in liver and atherosclerosis in hyperlipidaemia quails, and that GP can lower the lipoprotein levels in hyperlipidaemia animals.

Animals↗
PubMed1995

[99mTc-MIBI used for diagnosis of portal hypertension: an experimental study].

The authors investigated the relationship between portal-systemic shunting and portal pressure in 16 CCl4-induced cirrhotic wistar rats by 99mTc-MIBI photography of heart and liver. Based on radio-counts taken at 30 minutes after 99mTc-MIBI was given per rectum 8 rats or medial clonic vein 8 rats, heart radio-counts/liver radio-counts (H/L) and portal-systemic shunting index (SI) were recorded. It was shown that 1. H/L and SI of the two cirrhotic groups were greater than those of normals (P < 0.001); 2. H/L in cirrhotic rats by rectum 99mTc-MIBI administration was more closely related to free portal pressure (FPP, r = 0.83, P < 0.01) than in those by venous route (r = 0.74, P < 0.05) and its regressive formation FPP (kPa) = 0. 24 + 4.06 (H/L) was deduced and used to calculate portal pressure of cirrhotic rats. The very good relationship between the calculated and measured portal venous pressure was shown in a group of 12 cirrhotic rats (r = 0.85, P < 0.01). These findings suggested that the rectum administration of 99mTc-MIBI may be a useful method in calculating portal pressure and portal-systemic shunting in portal hypertensive patients.

Administration, Rectal↗
PubMed1994

[Molecular epidemiological characteristics of Salmonella typhi strains isolated in China. I. Analysis of Salmonella typhi strains isolated in China by multilocus enzyme electrophoresis].

Multilocus enzyme analysis by polyacrylamide gel electrophoresis (PAGE) was used to analyse 335 isolates of S. typhi from several provinces where high morbidity of typhoid fever was observed in recent years. We analysed 7 metabolic enzymes encoded by chromosome. The results showed that all the enzyme loci were polymorphic. The average alleles per locus was 7.4 (2-19): the mean genetic diversity per locus was 0.498 (0.198 0.883). There were 147 distinctive electrophoretic types (ETs) in 335 isolates. With cluster analysis by the average-linkage method, we found that there were 22 subclones, 12 clones among all isolates studied. Most isolates in 1988 from both Jiangsu and Zhejiang provinces belonged to one clone; the isolates from Guangxi Province in 1990 and parts of Hubei isolates belonged to one clone; the isolates from Hunan and Guizhou provinces during several-year period were homogeneous. However, the isolates from Xinjiang Autonomous Region were remarkebly different from other provinces, belonging to a particular clone. We also observed that the isolates from an outbreak or epidemic were from a one subclone.

Alleles↗
PubMed1992

Clinical evaluation of radioimmunoimaging with 131I-C0C183B2 monoclonal antibody against ovarian carcinoma by intraperitoneal injection.

Forty-eight cases subjected to radioimmunoimaging (RII) by intraperitoneal injection with 131I-C0C183B2 monoclonal antibody (MAb) prepared in our laboratory were studied. Thirteen of 14 cases of proved primary ovarian carcinoma were positive. In 11 follow-up cases of ovarian carcinoma after initial surgery and chemotherapy, 5 recurrences were positive and 6 cases without recurrence were negative; all were confirmed histopathologically after a second operation. One false negative was ovarian mucinous adenocarcinoma, which also negatively stained with C0C183B2 by the peroxidase anti-peroxidase method. Twenty of 23 cases of nonepithelial or metastatic carcinoma of the ovary, benign tumors, and benign diseases were negative. The sensitivity and specificity were 94.7 and 89.7%, respectively. If patients had complications with ascites, the MAb which positively stained with the cancer cells in the ascites was chosen for RII. For follow-up cases PAP staining with the tumor tissue from the initial surgery and the MAb should be done before RII. These are the principal factors that increase the positive rate and accuracy of RII. The intraperitoneal route seems to be a valuable method for clinical staging and tumor localization as well as for follow-up use.

Adult↗
PubMed1991

[Preparation and characterization of McAbs against the human crosslinked fibrin degradation product D-dimer].

D-dimer is a specific degradation product of crosslinked fibrin hydrolyzed by plasmin. Detection of D-dimer in blood is important for the diagnosis of thrombotic diseases and the surveillance of thrombolytic treatment. Therefore, D-dimer purification and preparation of anti-D-dimer McAb are necessary tasks. Using routine methods, we prepared four hybridomas which secrete anti-D-dimer McAb: HID1, HID2, HID3 and HID4. After five months in culture these hybridomas still secrete anti-D-dimer McAb. The titer of ascites McAb is 1:10(-5)-1:10(-6). HID1, HID2, and HID3 recognize the same or similar antigenic determinants and don't cross-react with coagulation factors, plasma or fibrinogen degradation products X, Y, D, and E fragments. HID4 recognizes another antigenic determinant and cross-reacts with fibrinogen degradation products X, Y and D fragments. Immunoblot results show that all of these McAbs react with a MW 190,000 band. These antibodies are being used in the development of enzyme-linked and latex immunoassay methods for the detection of D-dimer and will be useful in the diagnosis, evaluation and monitoring of thrombotic diseases and thrombolytic treatment.

Animals↗
PubMed1990

Structure of nogalamycin bound to a DNA hexamer.

The anthracycline antibiotic nogalamycin, which binds to DNA, is composed of a planar aglycone substituted on each end to form an unusual dumbbell-shaped molecule. At one end nogalamycin contains an uncharged nogalose sugar and a methyl ester. At the other end nogalamycin contains a positively charged bicyclo amino sugar. We report the crystal structure of nogalamycin bound to the self-complementary DNA hexamer d(m5CGTsAm5CG). In this complex, the cytosines are methylated at the 5 position and the DNA contains a phosphorothioate linkage at the TpA step. Two nogalamycin molecules bind to the 6-base-pair fragment of double-helical DNA. The drug has threaded between the phosphodiester backbones with three aromatic rings intercalated within the DNA. In the major groove, the bicyclo amino sugar forms two direct hydrogen bonds to span a CG base pair and interacts indirectly with the next base pair of the duplex via a water-mediated hydrogen bond. In the minor groove, a carbonyl oxygen of nogalamycin forms a hydrogen bond directly to N2 of a guanine. The DNA base pairs are severely buckled by up to 26 degrees and are also distorted in directions perpendicular to the Watson-Crick hydrogen bonds. This complex illustrates the deformable nature of DNA.

Base Sequence↗
PubMedDate not supplied

On modelling the kinestatic charge detector for digital radiographic diagnostic and portal imaging.

The kinestatic charge detection (KCD) principle has been a digital radiography technique for more than a decade. The advances of the KCD technique have gone from diagnostic imaging to portal imaging. However, little work has been done on understanding the selection of key KCD parameters and relationships between them. In the present study, an engineering model was established that could be used to optimize the placements of key parameters in terms of KCD system mechanical design. In the proposed KCD engineering model, the basic energy conservation law was applied to the process of ion transmission. It allows for the computation of the KCD design parameters such as the optimum grid placement, high voltage board tilt angle and grid wire space, as well as to provide recommendations on high voltage board and electric potentials and their ratio.

Computer Simulation↗