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Biomedical subjects

Z Liu

Publications and source records attributed to Z Liu.

At least 775 records · Page 43Linked to original sources
PubMed1998

[Expression regulation of major late promoter tripartite leader sequence in adenovirus late infection].

OBJECTIVE: To investigate the influence of adenovirus major late tripartite leader sequence on specific exportation of virus mRNA in the late phase of adenovirus infection. METHODS: We constructed a marked, human beta-actin minigene under the control of the glucocorticoid-inducible enhancer and promoter of mouse mammary tumor virus, and inserted it into the left end of the adenovirus type V genome. The promoter gene, designated MA, as well as of a sibling, which differed only in inclusion of a cDNA copy of the adenovirus major late tripartite leader sequence upstream of beta-actin sequences termed MtplA, in recombinant virus-infected cells was strictly dependent on addition of deoxymethesone to the medium. Nuclear and cytoplasmic reporter RNA species were compared by Northern blotting, primer extension and pulse-chase assay. RESULTS: The high concentrations of newly-synthesized RNA were accumulated in cytoplasm when tripartite leader sequence was present in reporter RNA, despite the equal rates of transcription of the two reporter genes. Nuclear and cytoplasmic reporter RNA species compared by Northern blotting, primer extension, and pulse-chase provided no evidence for altered processing induced by tripartite leader sequence. CONCLUSION: The tripartite leader sequence, known to facilitate translation of mRNA during the late phase of adenovirus infection, can also modulate mRNA export from the nucleus.

5' Untranslated Regions↗
PubMed1998

Avascular necrosis of the femoral head: MR imaging with radiological and histological correlation.

OBJECTIVE: To assess the value of MR in the diagnosis of avascular necrosis (AVN) of the femoral head. METHODS: MR images in 34 consecutive patients (26 men and 8 women) with AVN (57 hips) were reviewed. All lesions were confirmed by radiographic, radionuclide, computed tomographic, and/or histologic examination. Eleven specimens were obtained after total replacement of the hip. Four hips underwent biopsy. All MR images were obtained using a 0.35 T superconductive imaging unit with SE sequence. Specimens were cut coronally into 5 mm thick section and radiographs were obtained. RESULTS: There were four types of MR patterns of AVN. Type one appeared liner or patchy low signal area in the superoanterior portion of the femoral head. In type two, a band or ring of low signal intensity was found surrounding a central area of high signal intensity on T1WI and intermediate signal intensity on T2WI. The low signal band or ring consisted of thickened trabecular bone, mesenchymal and fibrous tissue, and amorphous acidophilic cellular debris. The central zones within the ring were composed of necrotic bone and marrow that had not been reached by the repair process. In type three, the focal subchondral region showed intermediate signal intensity on T1WI and high signal on T2WI surrounded by a low signal ring. The low signal ring consisted of thickened trabecular bone and little mesenchymal tissue. The central area was composed of mesenchymal tissue rich in capillaries and cystic necrotic zones. In type four, the signal intensity of femoral head was inhomogeneous on both T1WI and T2WI. There were low signal bands in the femoral neck surrounding the necrotic zone. Only limited areas of some lesions had signal intensity isointense with fat on T1WI and T2WI. The inhomogeneous area of low signal intensity consisted of a mixture of necrotic bone and marrow, amorphous cellular debris. The first type of MR pattern corresponded to the early stage of radiograph, and the third type of MR pattern to stage 5. The second and fourth type of MR patterns correlated less with the radiographic stage. CONCLUSIONS: MR imaging plays an important role in the diagnosis of AVN of femoral head especially in the early detection of AVN. The MR patterns of AVN is not correlated with radiographic stages exactly.

Female↗
PubMed1998

[Bacteriological study of chronic maxillary sinusitis in adults and observation of susceptibility to antibiotics].

The unilateral mucosal samples were taken from 42 patients and were cultured for bacteria. Meanwhile, the antimicrobial susceptibility was determined for 11 antibiotics and the beta-lactamase-producing bacteria(beta LPB) were examined. In 85.71% of all samples, bacterial growth was present. Anaerobic bacteria were present in 21.43% of cases. Predominant aerobic bacteria were alpha-hemolytic streptococci and coagulase-negative staphylococci. Predominant anaerobic bacteria were peptostreptococcus species and bacteroides species. The beta LPB were isolated from 40% patients, which were responsible for the resistance to some antibiotics. The antimicrobial susceptibility testing showed that the antibiotics containing beta-lactamase inhibitor, third-generation cephalosporins and third-generation quinolones had good efficacy. Our findings indicated the bacterial infection may not play the key role in the development of chronic sinusitis and the bacterial infection may not play the key role in the development of chronic sinusitis and the resistance to some antibiotics due to the high prevalence of beta-lactamase production must be considered when the antibiotics therapy is taken.

Adult↗
PubMed1998

[Nasal packing and packing materials chosing after ESS (with clinical analysis of 769 cases)].

Nasal packing after endoscopic sinus surgery is an important factor affecting the outcome of the operation. In order to discuss the clinical effect of no packing method and packing with different materials, we summarized our six years packing experiences of 769 cases (993 nasal cavities) undergoing ESS. The paper disclosed that if operation cavities didn't involve in middle turbinate, inferior turbinate and nasal septum, no packing method could be chosen; Otherwise, packing with different materials could be chosen, both methods could control the postoperative hemorrhage in a safe range. But in order to reducing patients' pain and operation cavities' reaction, it suggests operators had better choose no packing method or packing with absorbable hemostate gauze.

Adolescent↗
PubMed1998

[Relationship between plasma endothelin, nitric oxide, calcitonin gene-related peptide levels and pulmonary hemodynamics in patients with chronic cor pulmonale].

OBJECTIVE: To explore the relationship between plasma endothlin-1 (ET-1), nitric oxide (NO), calcitonin gene-related peptide (CGRP) levels and hypoxic pulmonary hypertension. METHOD: Cardiac catheterization was performed in 55 cases of chronic cor pulmonale to monitor the changes of their hemodynamic indices and to determine the levels of pulmonary arterial plasma ET-1, NO and CGRP. RESULT: The plasma ET-1 level of patients with pulmonary hypertension (Group A) was significantly higher than that of patients without pulmonary hypertension (Group B) and controls. The plasma NO level of group A was significantly lower than that of Group B and controls. The plasma CGRP level of ET-1 had a significantly negative correlation with PaO2 and positive correlation with pulmonary arterial pressure. The levels of NO and CGRP had significantly positive correlation with PaO2 and negative correlation with pulmonary arterial pressure. After 60-min oxygenation with 30% oxygen inhalation, the level of ET-1 decreased remarkably, but the levels of NO and CGRP went up notably. CONCLUSION: These results demonstrate that hypoxia affects plasma ET-1, NO, CGRP levels in patients with chronic cor pulmonale. ET-1, NO, CGRP play synergistic roles in regulation of pulmonary arterial pressure.

Adult↗
PubMed1998

[Effects of an extract of salviae miltiorrhizae (764-3) on structural remodeling of intra-acinar pulmonary artery in pulmonary hypertension due to chronic hypoxia and monocrotaline in rats].

OBJECTIVE: To investigate the effects of an extract of salviae miltiorrhizae (764-3) on the percentage of intra-acinar muscular artery (MA), partal MA(PMA) and nonmuscular MA(NMA) and collagen deposition in the media of MA in rats with hypoxia and MCT-induced pulmonary hypertension. METHOD: Wistar rats were divided into 12 groups. The hypobaric hypoxic 51 kPa (1 kPa = 7.5 mmHg) and MCT (60 mg/kg intraperitoneal injection) rats were treated with 764-3 (20 mg/kg), beta-aminopropionitrile (BAPN, 150 mg/kg) and 764-3 (40 mg/kg), respectively. At each time point, the hemodynamic and morphological parameters were measured. RESULT: After hypoxia for 2 weeks, the percentage of MA increased (P < 0.001), of NMA decreased (P < 0.001) and of PMA no obvious change; and after 4 weeks, the above changes became to be more striking and the collagen content in the media of MA increased (P < 0.001). The MCT-treated rats had more severe changes than the hypoxic rats. Both 764-3 and BAPN could inhibit the changes, decreased the collagen content and BAPN was more effective than 764-3(P < 0.05). CONCLUSION: 764-3 can partially inhibit collagen deposition in pulmonary arterioles attenuate hypoxia and MCT-induced pulmonary hypertension, reduce the percentage of MA, and has a moderate influence on collagen deposition as compared with BAPN.

Animals↗
PubMed1998

[Study of test method of A, B and H substances in human tissues].

With the help of the red cell adherence test, absorption-inhibition test and absorption-elution test, the A, B, O blood type of different tissues of corpses, whose ABO blood-type was known, was examined. The Substance of A, B, H type in 16 kinds of tissues of corpses was the same as in blood stain of corpses. The checked time limit of A, B, H substance of tissues preserved in different temperature was studied. The checked time of A, B, H substance of the tissues in 4 degrees C was longer than in room temperature, and the time in the hollow organ (vissera) shorter than that in parenchymatous organ (vissera).

ABO Blood-Group System↗
PubMed1998

[Effect of 764-3 on ventricular collagen deposition in pulmonary hypertension induced by chronic hypoxia and monocrotaline in rats].

OBJECTIVE: To observe the effect of 764-3 on ventricular collagen deposition in pulmonary hypertension induced by chronic hypoxia or monocrotaline (MCT) in rats. METHODS: Wistar rats were divided into 10 groups. The hypobaric hypoxia group received 764-3 20 mg/kg once daily subcutaneously and the MCT group treated with 764-3 40 mg/kg once daily. The hemodynamic and biochemical parameters were measured. RESULTS: At the time of 2 weeks and 4 weeks after treated with hypoxia or MCT, the pulmonary arterial pressure (PAP) of rats raised significantly and the right ventricular collagen content (RVCC) increased markedly. 764-3 could reduce the raised PAP induced either by hypoxia or MCT. It could lower the elevated RVCC of hypobaric hypoxia group at 2 weeks from 76.3 +/- 13.3 to 59.4 +/- 11.4 (P < 0.01), and the RVCC of MCT group lowered from 293.4 +/- 73.9 to 210.1 +/- 37.6(P < 0.01). CONCLUSION: 764-3 could partially prevent right ventricular collagen deposition induced by hypoxia and has therapeutic effect on that induced by MCT.

Animals↗
PubMed1998

[Effects of 764-3 on collagen deposition in hypertensive pulmonary arteries in hypoxic rats].

OBJECTIVE: To investigate the changes of collagen deposition in pulmonary arteries in chronic hypobaric hypoxic rats and the roles of 764-3. METHODS: Wistar rats were divided into 10 groups. The hypoxic (50.7 kPa) rats were treated with 764-3 (20 mg/kg, once daily) and beta-aminopropionitrile (BAPN, 150 mg/kg, twice daily), respectively. At the end of treatment, the hemodynamic morphological and chemical parameters were measured. RESULTS: Comparing with the normals, hydroxyproline (HYP) content of extrapulmonary artery (EPA) increased obviously in hypoxic rats, the smooth muscle cells (SMC) in the media of muscular intra-acinar pulmonary artery showed hypertrophy with change in phenotype, and a striking increment of collagen accumulation (P < 0.001); 764-3 could reduce HYP content of EPA (P < 0.05-0.001), and most of SMC in the media became thin and elongated with reversion of change of SMC phenotype, and collagen accumulation was reduced (P < 0.001). In addition, BAPN was more effective than 764-3 (P < 0.05). CONCLUSIONS: Excessive collagen accumulation in pulmonary arteries plays an important role in the maintenance of hypoxic pulmonary hypertension. 764-3 can partially inhibit collagen deposition in pulmonary arteries, attenuate hypoxic pulmonary hypertension, and has a moderate influence on collagen deposition in compared with BAPN.

Aminopropionitrile↗
PubMed1998

[Secondary infection of the ovarian endometriotic cysts].

OBJECTIVE: To explore the clinic manifestations, diagnostic methods and principles of management in the secondary infection of the endometriotic cysts of ovary. METHODS: Thirteen cases of the infected ovarian endometriotic cysts were analysed retrospectively in our hospital from Jan. 1990 to Dec. 1996. The diagnosis was confirmed by the operation and pathologic findings. RESULTS: The clinic manifestations were divided into five types, namely acute, subacute, chronic, occult and stabile types. The definitive diagnosis can be made by abdominal pain, fever and adnexal mass combined with B-scan findings and chocolate-brown purulent fluid which was punctured from the adnexal mass. Operation was the main method for treatment. CONCLUSIONS: Secondary infection of the endometriotic cyst is one of the gynecologic emergency. Correct diagnosis and prompt management are of vital importance.

Adult↗
PubMed1998

[Observation on effect of shenmai injection in treating patients of congestive heart failure].

OBJECTIVE: To observe the clinical therapeutic effect of Shenmai Injection (SMI) in treating patients of congestive heart failure. METHODS: Effect of 16 cases treated with SMI or potassium magnesium aspartate was observed by randomized crossover method and compared. RESULTS: By using SMI for 2 weeks, patients' left ventricular ejective fraction (LVEF) could be increased from 29.5 +/- 9.0 to 36.6 +/- 10.2 (P < 0.05), the heart function of 68.75% patients was improved, no side effects or toxicity was observed. Potassium magnesium asparate could improve heart function in 37.50% patients only but with no effect on LVEF. CONCLUSION: SMI is an effective and safe therapy in treating patients with congestive heart failure.

Adult↗
PubMed1998

[Study on effect of acupoint sticker of TTS-ST93-1 in treating motion sickness].

OBJECTIVE: To observe the effect of Transdermal Therapeutic System ST93-1 (TTS-ST93-1) by acupoint sticking in treating motion sickness (MS). METHODS: One hundred and sixty-three young volunteers with history of MS recently were subjected to a 3 hours journey by track and armored car, and divided randomly into tested, positive control and negative control groups, treated with TTS-ST93-1 plaster, TTS-Scopolamine plaster and placebo (lactose plaster) respectively. The TTS-ST93-1 plaster was stuck on Neiguan (P6) or Shenque (CV8) or Qimai (TE18) point and the effect of treatment was observed by double-blind method. RESULTS: The mean effective rate of tested group was 95.9%, which was significantly different to that of the negative control group (P < 0.01). In the tested group, the protection rate of plaster stuck on Shenque was 81.4%, on Neiguan was 45.5% and on Qimai was 100%, with an average of 76.0%, which was significantly different to that of the negative control group. The protection rate of TTS-Scopolamine plaster was merely 27.3%. The side effects of TTS-ST93-1 plaster were mouth dryness, sleepiness and fatigue, as compared with the negative control group, the difference was insignificant. No allergic reaction of skin such as swelling, pain or itching was found in the tested group. CONCLUSION: Acupoint sticker of TTS-ST93-1 was an effective treatment for MS with less side effect and no allergic reaction of skin.

Acupuncture Points↗
PubMed1998

Effect of hypoxia on motion sickness induced by optokinetic stimulation.

The purpose of this experiment was to study the effect of hypoxia on motion sickness (MS) induced by optokinetic stimulation and to observe its character and principle. Twenty healthy male subjects aged 18-25 years received optokinetic stimulus (OS) and hypoxic-optokinetic stimulus (HOS) according to the "Latin Square" arrangement and "Self-control" methods. Motion sickness symptoms (MSS) and optokinetic horizontal nystagmus (OKHN) were recorded and analysed. The results indicated: (1) MS average score for HOS was higher than that for OS (P<0.001); (2) Slow phase velocity(SPV) of OKHN in HOS was lower than that in OS (P<0.001). The results clearly showed that moderate hypoxia could deteriorate the MS induced by OS. It provided a method for the screening of MS sensitivity.

Adolescent↗
PubMed1998

Enzyme immunoassay for cuprozinc-superoxide dismutase in whole blood and urine during head down bed rest.

A highly sensitive enzyme immunoassay system for the determination of cuprozinc-superoxide dismutase (Cu, Zn-SOD) in whole blood and urine with horseradish peroxidase as a labeling enzyme was reported. It measures Cu, Zn-SOD with good repeatability of 0.05-5 ng. Coefficients of variation were 1.17%-7.94% for within-a-day assay and 1.94%-10.73% for between days assay. The average recoveries from whole blood and urine were 101.0%-113.8% and 96.0%-116.0%, respectively. Using this enzyme immunoassay, the normal range of Cu, Zn-SOD concentration in the whole blood was found to be 281.66 +/- 25.45ng/ml, and it tended to decline 3d after HDBR -6 degrees. The normal range in urine Cu, Zn-SOD concentration was 0.87 +/- 0. 33 micrograms/g of creatinine, it decreased significantly on the 3rd day during HDBR -6 degrees. Both of them recovered to normal on the 6th day during HDBR -6 degrees.

Adult↗
PubMed1998

[Biological effect of space flight on edible fungi onboard recoverable scientific satellite].

In order to breed good variety of edible fungi and provide data of cultivation of edible fungi in Controlled Ecological Life Support System (CELSS) in the future, 2 species of the edible fungi (Pleurotus ostreatus and Flammulina velutipes )were carried into space by a recoverable scientific satellite. A series of biological tests and cultivation experiments were done with the mycelia and sporocarp of these edible fungi. It was demonstrated that the edible fungi recovered from the satellite have superior characters such as: earlier sporocarp production, higher yield, higher transformation rate of raw fiber and organic matter and higher content of polysaccharide and endogenous hormones than the control.

Abscisic Acid↗
PubMed1998

[Selection of key biological components (KBC) for Controlled Ecological Life Support System (CELSS)].

Biological components are key parts in Controlled Ecological Life Support System (CELSS), the future experimental success will depend to a large extent on the suitability of selected KBCs. For this purpose, 15 KBCs including 4 higher plants(vegetables), 5 microorganisms, 5 microalgae and 1 lower plant were selected from lots of biological species for CELSS. These results laid a solid foundation for our studies of CELSS.

Ecological Systems, Closed↗