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Biomedical subjects

F Zhang

Publications and source records attributed to F Zhang.

At least 235 records · Page 13Linked to original sources
PubMed2000

[The effects of experimental osteoporosis on bone tissues around hydroxyapatite implants].

OBJECTIVE: To investigate the effects of estrogen decreasing on bone tissues around implants in ovariectomized rats. METHOD: Forty-two female Wistar rats, aged 32 weeks, were used in this study. First, cylindrical hydroxyapatite-coated implants were planted in the proximal part of tibiae of the rats. Then, the rats in experimental group and control group were respectively performed ovariectomy and false surgery after 56 days, the rates were killed in 28, 84 and 168 days after operation, and tibiae were taken out to prepare undecalcified sections. The section were examined by routine histomorphometric measurement and the dynamic changes of trabecular bone and extent of contact between the implants and bone tissue around them. RESULTS: Twenty-eight days after operation, the density of trabecular bone around the implant in experiment group was found significantly reduced compared with the control group. In the area of cortical bone, no difference was found in the extent of implant-bone contact between two groups, while in the area of spongy bone the extent of contact was different obviously. CONCLUSION: Ovariectomy in Wistar rats can induce significant osteoporosis around implant, these finding suggest that menopause in women patients may also induce osteoporosis around implanted artificial teeth and affect the prognosis. Therefore, the patients should be carefully observed during the implant treatment course.

Animals↗
PubMed2000

[Investigation of urinary interleukin-6 level in chronic renal failure patients and the influence of Rheum palmatum in treating it].

OBJECTIVE: To assess the clinical significance of urinary interleukin-6 (IL-6) level in chronic renal failure (CRF) patients and the effect of Rheum palmatum (RP) in treating it. METHODS: RP and captopril were given to the study group, while captopril was given to the control group alone, and level of urinary IL-6 was determined by sandwich-ELISA. RESULTS: Urinary IL-6 level in CRF patients was obviously higher, than that in healthy control (P < 0.01). After treatment, the urinary IL-6 and serum creatinine reduced significantly in the study group (P < 0.05), and there was significant difference compared with that in the control group (P < 0.05). CONCLUSIONS: Determination of urinary IL-6 level is useful in studying the severity of immune inflammation of CRF. RP improves renal function by inhibiting the production of IL-6 and lowering immune inflammation.

Adolescent↗
PubMed2000

[Effects of B-ultrasonic radiation during pregnancy on reproductive outcome].

OBJECTIVE: To study the effects of B-ultrasonic scanning during pregnancy on reproductive outcome, including pregnant outcome and neonatal status. METHODS: Data of reproductive outcome and B-ultrasonic examination were extracted from the questionnaires and obstetric records of 12,224 primigravidas in eight hospitals of Beijing during May 1992 to April 1993. Their reproductive outcomes were analyzed according to frequency and gestational weeks they had B-ultrasonic examination taken, adjusted for potential confounding factors, such as age at pregnancy, smoking and drinking during pregnant period and history of spontaneous abortion, by logistic regression. RESULTS: There was no statistically significant difference in reproductive outcomes between groups, who had B-ultrasonic examination taken for two, three and four times or more and who had only once, respectively, who had more than four times and who had less than three times, and who had their first examination before and after the eighth week of gestation, or before and after the 12th week of gestation. CONCLUSION: No adverse reproductive outcome due to exposure to diagnostic dose of B-ultrasound radiation during pregnancy has been found.

Abortion, Spontaneous↗
PubMed2000

[Effects of antisense human telomerase RNA on growth of human gastric cancer cells].

OBJECTIVE: To observe the inhibitory effects of antisense human telomerase RNA (hTR) on growth of human gastric cancer cells. METHODS: SGC7901 cell line was transfected with antisense hTR expression vector (pBBS-hTR) by lipofectAMINE. The gene transfected cells were cultured in vitro and then inoculated into nude mice. RESULTS: Antisense hTR expression was enhanced and sense hTR expression inhibited in clones containing antisense hTR after hygromycin resistant selection which induced tumor cells apoptosis. The growth rate of the major gene transfected cells in culture and tumorigenesis of the transfected cells in nude mice were significantly reduced in comparison with those of controls. The survival time of nude mice inoculated with the gene transfected cells was markedly prolonged when compared to controls. CONCLUSIONS: The malignant proliferation of gastric cancer cell can be reversed by antisense hTR induced cell apoptosis. Thus antisense hTR may serve as a potential therapeutic approach to the treatment of human cancer.

Animals↗
PubMed2000

[Comparative study of three common G6PD gene mutations in Yao and Han People in Guangxi].

OBJECTIVE: To study G6PD gene mutation diversity in Yao and Han people in Guangxi and compare the genotypic frequencies. METHODS: The three common G6PD gene mutations in Chinese were investigated in 34 G6PD deficient individuals from Yao and 37 from Han people by using an amplification refractory mutation system (ARMS). RESULTS: Among 34 cases of G6PD deficiency of Yao people, the genotypic frequencies of G1376T, G1388A and A95G were 41.2%, 26.5% and 14.7%, respectively. A case of C1311T was detected. As compared with that in Han people, the respective frequencies were 16.2%, 40.6% and 5.4%. CONCLUSION: The main G6PD mutations in Yao people were the same with Han people in Guangxi, but G1376T mutation was higher than that in Han people. The C1311T mutation in Yao people in Guangxi was reported for the first time.

Adolescent↗
PubMed2000

[Chinese drugs for invigorating spleen to remove dampness, activating blood circulation to eliminate turbid in retarding progression of chronic renal failure].

OBJECTIVE: To investigate the effect of Chinese drugs (CD) for invigorating Spleen to remove dampness, activating blood circulation to eliminate Turbid in retarding progression of chronic renal failure (CRF). METHODS: Thirty-nine patients with CRF were divided into two groups randomly, 18 patients in the control group were treated with low protein diet and controlling blood pressure and 21 patients in the CD group were treated similarly with that of the control group but with additional CD. Levels of serum creatinine (SCr), blood urea nitrogen (BUN), blood albumin (Alb), cholesterol (CH), triglyceride (TG), high-density lipoprotein (HDL) and hemoglobin (Hb) were checked every 2 months, and the rate of progression of CRF was estimated by slope of the creatinine reciprocal (1/SCr) with time (month). RESULTS: Levels of SCr and BUN in the CD group were significantly lower and HDL markedly higher than those in the control group, P < 0.05. Mean slopes of the creatinine reciprocal with time in the two groups was significantly different, P < 0.01. CONCLUSION: Additional CD treatment based upon the protein diet and controlling blood pressure could retard the progression process of CRF evidently.

Adult↗
PubMed2000

[Effects of bacterial protective liquid on radiation biology effect of mouse bone marrow cells].

To study the relationship between bacterial protective liquid (BPL) and the biological effect of mouse bone marrow cells by gamma-ray irradiation, apoptosis and the number of CD4+, CD8+ and NK cells were analyzed by flow cytometry(FCM), the results showed that BPL decreased the apoptosis and increased the proliferation of cells(P < 0.01). The theorem of action was related with raising the percentage vitality of NK cells and the quantity of CD4+ and CD8+. This study proved that BPL might have protective effect against radiation injury.

Animals↗
PubMed2000

[Structure determination of alkyd resins by simultaneous pyrolysis methylation gas chromatography-mass spectometry].

Several types of alkyd resins have been analyzed by simultaneous pyrolysis methylation gas chromatography mass spectrometry (SPM-GC-MS). The samples were mixed with tetramethylammonium hydroxide, and the process included simultaneous pyrolysis derivatization and mass spectrometry determination. SPM-GC-MS conditions: a vertical microfurnace-type pyrolyzer was directly attached to a gas chromatograph-mass spectrometer. About 20 ug of the mixed alkyd resin sample was introduced into the center of the pyrolyzer at 450 degrees C under the flow of helium carrier gas. The inlet mode was split with an injection interval of 10 s and the inlet pressure was 82.7 kPa. The gas chromatograph was fitted with a fused-silica capillary column ( SE-54 30 m x0.25 mm i.d. x 0.25 um). Temperature program settings were: initial temperature, 40 degrees C, hold 2 min; increase at 6 degrees C min 1 to 220 degrees C, hold 14 min; increase at 10 degrees C min 1 to 280 degrees C, hold 8 min. All pyrolysis products referred to were identified by mass spectrometry. The temperature of the ion source was 210 degrees C and that of the transfer line was 250 degrees C. The technique could give additional information about the composition of the dibasic acids, polyols, six types of drying oils, and modified alkyd resins. The method is sensitive, accurate, convenient, and involves minimal sample manipulation.

English Abstract↗
PubMed2000

[Study on the mechanism of hemocompatibility of titanium oxide films].

In this paper a study on the facts affecting blood compatibility of titanium oxide films synthesized by ion beam assisted deposition is presented, and the mechanism of blood compatibility is discussed. We think that the blood compatibility is determined by surface energy and work function of the film. The protein adsorption is determined by surface energy. An area with a range of values of polar and dispersion components of surface energies, where good protein adsorption property will exhibit, was defined. That is, more human serum albumin (HSA) and less human fibrinogen (HFG) will be adsorbed in this area. Work function is also an important factor to influence blood compatibility. Low work function can inhibit the decomposition of HFG and improve thromboresistance.

Adsorption↗
PubMed2000

[Role of beta-adrenoceptor antagonists in the control of kindling models in rats].

AIM: To study the role of beta-adrenoceptors (beta-AR) and their subtypes in the control of kindling models in rats. METHODS: Electrical amygdala kindling, pentylenetetrazol (PTZ) kindling models in rats and maximal electroshock (MES) in mice were used to observe the effects of beta-AR agonists and antagonists. RESULTS: The beta-AR antagonist propranolol 15 mg.kg-1 i.p. delayed the development of amygdala kindling; while propranolol 1-20 mg.kg-1 i.p. and beta-AR antagonist metoprolol 25-400 mg.kg-1 ig significantly increased the afterdischarge threshold and reduced the seizure severity in both kindling models (P < 0.01). beta 1-AR agonist dobutamine completely reversed the inhibitory effect of propranolol, while the beta 2-AR agonist terbutaline showed no effect on propranolol. Metoprolol 200 and 800 mg.kg-1 ig significantly inhibited MES in mice (P < 0.01). CONCLUSION: Central beta 1-AR is involved in the inhibitory effects on amygdala kindling and PTZ kindling models in rats.

Adrenergic beta-1 Receptor Antagonists↗
PubMed2000

[Primary melanoma of the central nervous system].

OBJECTIVE: To investigate the status of diagnosis and treatment of primary melanoma of the central nervous system. METHODS: Six patients with primary melanoma of the central nervous system underwent surgery in our department between 1969-1999. Clinical presentation, operative findings, histological diagnosis, and prognosis were reviewed. RESULTS: No typical symptom occurred in these patients. The lesions can mimic meningiomas and acoustic neuromas in location and radiological appearance. Total removal of tumors was only achieved in one case. Histological examination showed malignant lesions in 3 cases and benign lesions in others. Five cases were followed up and only two were alive. CONCLUSIONS: Primary melanomas are extremely rare tumors of the central nervous system. Surgical removal of the lesion may result in prolonged remission or cure.

Adolescent↗
PubMed2000

[High dose intravenous immunoglobulins in treating systemic lupus erythematosus-associated thrombocytopenia].

OBJECTIVE: To study the effect of high dose intravenous immunoglobulins(IvIg) in systemic lupus erythematosus (SLE)-associated thrombocytopenia. METHODS: A case-control study was undertaken to assess the effectiveness of different therapeutic regimens (oral prednisone, IvIg, bolus methylprednisolone(MP), and IvIg plus bolus MP) in improving SLE-associated thrombocytopenia. RESULTS: For SLE-associated thrombocytopenia, IvIg, bolus MP, and IvIg plus bolus IvIg significantly shorten the time to reach a peak platelet count, which was (6.2 +/- 4.4) days, (7.3 +/- 4.9) days, and (3.8 +/- 2.4) days respectively in comparison with oral prednisone, which was (31.0 +/- 17.8) days (P< 0.01); if high dose IvIg and MP in combination, the time was also shorter than bolus MP alone (P < 0.05). The elevation of platelet count in groups receiving IvIg, bolus MP, and IvIg plus bolus MP were significantly higher than as in group receiving oral prednisone therapy(P < 0.05). CONCLUSIONS: High dose IvIg is a useful therapy in improving SLE-associated thrombocytopenia.

Adult↗
PubMed2000

[Luminescence enhancement of phthalate-Eu-Sr complex].

Using doped method low rare earth concentration and chelates matrix luminescence was successful in the chelates systems. The luminescence of phthalate-Eu-Sr complex is an example. The experimental results show that the complex luminescence would be enhanced co-doped other metal ions(shch as Mn), because other metal ions can transfer energy to rare earth ion. Addition of the second ligand will enhance the complex luminescence, too. In the FTIR spectra of co-doped complexes, the vibrations of nu a(COO-), nu as(COO-), nu CC have shifted, which show that the co-doped metal ions have influence on the molecular structure.

Chelating Agents↗
PubMed2000

[Studies on the gas phase reaction of ablated Ni+ with molecular flows of alcohols in the time-of-flight mass spectrometer].

A apparatus combining molecular flows, laser ablation and time-of-flight mass spectrometer was first designed, in which the gas phase reactions of metal ions with organic compounds were realized. In a small quartz cell of it, laser ablated Ni+ meet and react with molecular flows of alcohols, and their product ions were detected by the time-of-flight mass spectrometer. The gas phase reactions of Ni+ with C2-C6 alcohols were studied. All of which can be explained by the following mechanism: (1) Insertion of Ni+ into bonds of alcohols; (2)Following each insertion, a beta-hydrogen shift onto Ni+ to produce intermediate; (3) Dessociation of each intermediate by loss of neutral molecular to give product ion.

English Abstract↗
PubMed1999

Crystal structure of layered bis(ethylenediamine)nickel hexavanadate as a new representative of the V6O14 series.

A new [Ni(NH(2)CH(2)CH(2)NH(2))(2)](V(6)O(14)) compound has been synthesized hydrothermally and was found to crystallize in the monoclinic system. The single-crystal X-ray data leads to a disordered structure, which can be decomposed into two ordered models with different stacking of the V(6)O(14) layers. The structure of the layer is the same in both models and represents a new member of the V(6)O(14) series. All known structures from this series are constructed from the same chain of square pyramids (SP), which share alternatively adjacent or opposite edges of their bases. The differences lie in the orientation of the SP chains which are joined together by sharing corners with tetrahedra to form the layers. Combinatorial analysis of the V(6)O(14) structures was conducted, yielding ten possible symmetry groups for the series of V(6)O(14) layers. The known structures belong only to the three simplest cases with the highest symmetry.

Journal Article↗
PubMed1999

Design and synthesis of novel alpha(1)(a) adrenoceptor-selective antagonists. 1. Structure-activity relationship in dihydropyrimidinones.

Dihydropyrimidinones such as compound 12 exhibited high binding affinity and subtype selectivity for the cloned human alpha(1a) receptor. Systematic modifications of 12 led to identification of highly potent and subtype-selective compounds such as (+)-30 and (+)-103, with high binding affinity (K(i) = 0.2 nM) for alpha(1a) receptor and greater than 1500-fold selectivity over alpha(1b) and alpha(1d) adrenoceptors. The compounds were found to be functional antagonists in human, rat, and dog prostate tissues. Compound (+)-103 exhibited excellent selectively to inhibit intraurethral pressure (IUP) as compared to lowering diastolic blood pressure (DBP) in mongrel dogs (K(b)(DBP)/K(b)(IUP) = 40) suggesting uroselectivity for alpha(1a)-selective compounds.

Adrenergic alpha-1 Receptor Antagonists↗