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Biomedical subjects

H Li

Publications and source records attributed to H Li.

At least 1,135 records · Page 63Linked to original sources
PubMed1998

Erythrocyte and plasma Ca2+, Mg2+ and cell membrane adenosine triphosphatase activity in patients with essential hypertension.

OBJECTIVE: To assess the relationships between plasma and intracellular Ca2+, Mg2+ and blood cell membrane adenosine triphosphatase (ATPase) activity in normotensive and hypertensive subjects. METHODS: Plasma and intracellular Ca2+, Mg2+ were measured with atomic absorption spectrophotometry, and red blood cell membrane Na(+)-K+ ATPase and Ca(2+)-ATPase activities were determined with colorimetric method in 55 patients with essential hypertension and 32 normotensive controls. RESULTS: The results showed that the hypertensive group consistently demonstrated a significant decreased activity of ATPase studied, with significantly lower plasma Ca2+ and higher cytosolic Ca2+ levels when compared with those in normotensive group (P < 0.01 or P < 0.05, respectively). No significant differences were found in either plasma Mg2+ or intracellular Mg2+ level between the two groups. CONCLUSIONS: This study suggests that patients with essential hypertension have widespread depression of cell membrane Na(+)-K(+)-ATPase and Ca(2+)-ATPase activities with plasma Ca2+ depletion and cytosolic Ca2+ overload, which may reflect an underlying membrane abnormality in essential hypertension. The cellular abnormalities may be related to the defective transport mechanisms that in turn may be aggravated by plasma Ca2+ depletion.

Adult↗
PubMed1998

[Effect of cyclic loads on revascularization in healing of bone defect].

In order to study the biomechanical effect of cyclic loads on revascularization in bone healing, 20 rabbits were chosen for following experiments. Two 2 mm in diameter holes were made at the middle segment of both right and left tibia. A 2 mm in diameter nail was put in 15 mm proximal to the upper hole, and another was put in 15 mm distal to the lower hole. The wound was covered by direct suture with the ends of the nails kept 15 mm out of skin. The medial ends of the two nails were fixed by an iron plate, while the lateral ends were left for cyclic loads. Three Hz cyclic loads, which was near to the cyclic forces when a rabbit runs, was added to the left tibia for experiment, and no loads was add to the right tibia for control. A group of five rabbits were sacrificed respectively in 5, 10, 20 and 30 days postoperatively. The solution of 2% India ink and gelatin was irrigated from aorta to the bone defects. Then the tibia was removed for histologic study. The changes of cells and microvessel were observed. It was shown that the revascularization in experiment group was about 7 days earlier than that of control. The effect was at its peak from 10 to 30 days. It was concluded that cyclic loads could promote revascularization in the healing process of bone defect.

Animals↗
PubMed1998

[Anatomical and clinical studies on the free posterior leg flap pedicled with the lateral popliteal cutaneous artery].

OBJECTIVE: To investigate the feasibility of free transference of the posterior leg flap which is supplied by the lateral popliteal cutaneous artery. METHODS: Anatomical dissection is performed in twenty-two freshly amputated adult lower extremities. RESULTS: The discovery rate of the lateral popliteal cutaneous artery is 100%. The vessel is 20.0 +/- 5.7 cm in length with an exterior diameter of 1.28 +/- 0.25 mm at the junction of the popliteal artery. The course of the artery is constant, and it is usually accompanied by the lateral sural cutaneous nerve. Seven operations using this free flap have been performed successfully. CONCLUSION: The flap is suitable for repairing medium-sized soft tissue defects or for functional reconstruction.

Adolescent↗
PubMed1998

[The study of autoantibodies in women with habitual abortion of unknown etiology].

OBJECTIVE: To evaluate the relationship between habitual abortion of unknown etiology and autoantibodies. METHODS: IgG and IgA antibodies against cardiolipin, specific antinuclear double-stranded DNA and single-stranded DNA were measured by enzyme linked immunosorbent assay (ELISA). Antinuclear antibody, smooth muscle antibody, antimitochondrial antibody and antiheart muscle antibody were performed by indirect immunofluorescence assay. Antiextractable nuclear antigen's antibodies were determined by immunodiffusion assay. RESULTS: Most women with habitual abortion of unknown etiology showed higher incidence of antibodies to cardiolipin, nuclear, smooth muscle compared with normal multigravida control (P < 0.05). CONCLUSIONS: These results indicate that most women with habitual abortion of unknown etiology have a higher level of autoreactivity, which may affect the course of pregnancy. The incidence of antismooth muscle antibody in women with habitual abortion of unknown etiology is also increased compared with normal multigravida control.

Abortion, Habitual↗
PubMed1998

[Determination of tetradecyl pyridyl bromide in waste water by flame atomic absorption spectrometry].

A indirect method for the determination of tetradecyl pyridyl bromide (TPB) was established (TPB) by flame atomic absorption spectrometry (FAAS). TPB was combined with cadmium tetrathocyanate to make neutral ion association compounds, which are extracted into xylene. The concentration of TPB can be indirectly determined by the absorption of cadmium in xylene layer with flame atomic absorption spectrometry. The linear range of TPB is 0.03-0.80 mg/L. The sensitivity is 0.0212 mg/L x 1%. When the method was applied to the analysis of waste water, the recovery is from 98% to 104% and the RSD is less than 9.16%.

Hydrocarbons, Brominated↗
PubMed1998

[Behavioral-teratological effects of caffeine on mice].

Pregnant ICR mice were exposed to caffeine at levels of 0, 4, 20 and 100 mg/kg during pregnancy. The behavioral-teratological tests indicated that the retardation of development, the obstruction of early reflexes and sensation and decline of learning ability existed in the offsprings of 20 and 100 mg/kg groups. The number of the dead fetus increased in the group of 100 mg/kg coffeine treated mice. No morphological changes were found.

Animals↗
PubMed1998

[Effect of vasectomy on apoptosis in spermatogenic cells of the male rat].

To explore the effect of vasectomy on apoptosis of spermatogenic cells, we have detected apoptosis in the testis of vasectomized and sham-operated adult rats within a period of 12 postoperative weeks by means of flow cytometry and TUNEL (terminal deoxynucleotidyl transferase-mediated deoxyuride triphosphate nick-end labeling) method. Flow cytometry found that, in vasectomized rat, the sub-haploid peak was higher and the percentage of cells with sub-haploid was increased. The total number of positive TUNEL cells in the vasectomized group was greater than that in the sham-operated group (P < 0.001). Compared with the same time-phased sham-operated subgroups, the number of apoptotic spermatogonia and primary spermatocytes in the testes of the subgroups 2 weeks, 6 weeks and 10 weeks after vasectomy as well as the number of spermatogonia of the subgroup 12 weeks after vasectomy were significantly higher (P < 0.05). These findings demonstrate that vasectomy could enhance the apoptosis of spermatogenic cells.

Animals↗
PubMed1998

[Relationship between change of erythrocyte membrane lipid composition and pregnancy induced hypertension].

OBJECTIVE: To study the cause of decreased erythrocyte deformability and its relation to pregnancy induced hypertension (PIH). METHODS: The cholesterol and phospholipid content of erythrocyte membrane in 24 non-pregnant healthy women, 22 normotensive pregnant women and 36 cases with PIH were determined using automatic biochemical analysor, Gas chromatography and modified colorimetric method. RESULTS: The cholesterol content and the cholesterol/phospholipid (C/P) ratio of the erythrocyte membrane were obviously higher in the group with moderate or severe PIH than that in the nonmotensive pregnancies (P < 0.01). There was no significant difference between mild PIH group and the normotensive pregnant group (P > 0.05). CONCLUSION: The increase of cholesterol content and C/P ratio in the erythrocyte membrane might be involved in the pathophysiology of PIH. The alteration of cholesterol content in the erythrocyte membrane probaby reflected the disturbance of serum lipid metabolism.

Adult↗
PubMed1998

[Determination and significance of nitric oxide and tumor necrosis factor-alpha induced by peripheral blood monocyte in vitro in patients with malignant bone tumors].

Peripheral blood monocytes from 15 cases of malignant bone tumors and 12 cases of health volunteers were seperated and induced by lipopolysaccharide(LPS) for 48-hour culture. The supernatant was collected for determining the content of nitrite and tumor necrosis factor-alpha(TNF-alpha) (by Griess and ELISA methods, respectively). The results were as follows: The content of nitrite and TNF-alpha in patients with malignant bone tumors was significantly higher than that in normal control; the content of nitrite and TNF-alpha in the malignant bone tumor group presented the positive correlation (r = 0.8909, P < 0.01). The results suggest that NO and TNF-alpha produced by activated macrophages may be related to the pathogenesis of malignant bone tumors.

Adolescent↗
PubMed1998

[Study on the status of methylation of Rb gene promoter in human esophageal cancer and effect of NMBzA on Rb gene promoter in monkey esophageal epithelium].

OBJECTIVE: To elucidate the cause of abnormal Rb expression in esophageal cancer (EC). METHODS: Methylation of Rb gene promoter was examined with restriction endonuclease digestion and PCR amplification. RESULTS: Of the 30 specimens of EC, 10 (33.3%) had Msp I type hypermethylation of the Rb gene promoter while 12 (40.0%) had Hpa II type hypermethylation and one had both type of hypermethylation. In monkey fed with a single dose of NMBzA (30 mg/kg) on day 0, increasing hypermethylation of both types of the Rb gene promoter in esophageal epithelium was found on day 1, 2 and 3 but reduced on day 5. CONCLUSION: These data suggest that abnoromal expression of Rb gene may be related to hypermethylation of its promoter and carcinogen NMBzA can induce such hypermethylation in monkey esophageal epithelium.

Animals↗
PubMed1998

[Malignant mixed mesodermal tumors of the ovary: a clinical analysis of 12 cases].

OBJECTIVE: To explore the clinical characteristics, treatment and prognostic factors of patients with malignant mixed mesodermal tumors of the ovary (MMMTO). METHODS: Clinical data of 12 patients with MMMTO between 1983-1997 were reviewed retrospectively. The median age of the patients was 50.7 years. According to FIGO staging system (1985), there were 4 cases in stage II, 6 in stage III and 1 in stage IV. Staging was unclear in the remaining case. Heterologous and homologous elements were present in the primary ovarian tumors in 4 and 8 of the 12 patients, respectively. All patients received cytoreductive surgery. Eleven of them received postoperative chemotherapy and 3 of these eleven patients received additional radiotherapy of pelvic field. RESULTS: The median survival of this group of 12 patients was 24 months. The 2- and 5-year survival rate was 33.3% (4/12) and 8.33% (1/12), respectively. The 2-year survival rate of stage II and III was 50% and 33.3% respectively. One patent in stage IV died within 1 year. Four of the 8 patients with homologous histology survived over 2 years while all the 4 cases with heterologous histology died within 2 years. Five of the 11 patients (45.5%) received combination therapy died within 1 year while 1 patient treated with surgery alone died within 6 months. CONCLUSIONS: The prognosis of MMMTO is rather poor. Surgery combined with chemotherapy and/or radiotherapy seems to be a better choice of approach. The histological tpyes of tumor and stage of the disease are related to prognosis.

Adult↗
PubMed1998

[The clinicopathological and immunophenotypical features of 162 cases of gastrointestinal stromal tumor].

OBJECTIVE: To demonstrate the clinicopathological and immunophenotypical features of gastrointestinal stromal tumor (GIST). METHODS: One hundred and sixty-two cases of GIST were retrospectively studied. Among them, forty-six cases were immunostained using antibodies against vimentin, CD34, muscle specific actin (MSA), smooth muscle actin (SMA), neuron specific enolase(NSE), S-100 protein, synaptophysin (SYN), cytokeratin(CK), CEA, LCA. RESULTS: Clinically, male patients predominated with a male to female ratio of 3.8:1. The average age was 50 (range 6-74). The most common symptoms were gastrointestinal bleeding and abdominal mass in 45% and 39% of the cases, respectively. The common anatomical locations were stomach (43%), ileum (20%), jejunum (18%). Pathologically, all the tumor arose from the muscular layer. The tumor diameter varied from 0.5 to 43 cm. In 55% of the cases, the tumor was malignant. The main component cell types were spindle and epithelioid in appearance. Immunophenotypically, percentage of positivity for the 10 antibodies was as follows: vimentin, 100% (39/39), CD34, 64% (23/36), MSA, 47% (16/34), SMA, 41% (14/34), NSE, 61% (17/28), S-100 protein, 19% (4/21), SYN, 15% (3/20), CK, CEA, and LCA were negative. CONCLUSION: GIST is the most common mesenchymal tumor of the gastrointestinal tract. Immunostaining confirms that only some of the GIST shows partial differentiation toward smooth muscle, neuron, or both.

Adolescent↗
PubMed1998

[The effect of expressed human apolipoprotein AI on plasma high density lipoprotein level in transgenic mice].

OBJECTIVE: To study the regulation of human apolipoprotein AI(h-apo AI) gene expression and its role in high density lipoprotein (HDL) metabolism. METHODS: Transgenic C57BL/6 mice established in this laboratory with human apoAI gene containing mouse metallothionein-I(MT-I) promoter were used for investigation. RESULTS: Southern blot identified the presence of 4-15 copies of h-apo AI gene in the transgenic mice. Northern blot showed that human apo AI mRNA was expressed mainly in the liver and kidneys, and the high level of h-apo AI mRNA was obtained in liver, kidneys and small intestine after Zinc(Zn) induction. Total Plasma apoAI Level in transgenic mice was significantly increased than that in the controls, and a high h-apoAI level was detected in the transgenic mice (46% increased after Zn induction). Additionally, total and HDL cholesterol levels were noticed to be highly increased to 47% before and 103% after Zn induction in the transgenic mice comparing to that of the controls. The plasma HDL and h-apoAI levels were significantly correlated (r = 0.85, P < 0.01) in the transgenic mice. CONCLUSION: Apo AI has a profound effect on regulating HDL levels in the transgenic mice. This animal model is considered appropriate for studying the effect of apoAI on lipid metabolism and the mechanism combating atherogenesis.

Animals↗
PubMed1998

[Analysis of critically ill patients with bacteremia].

OBJECTIVE: To study the epidemiology of bacteremia of critically ill patients and the mortality associated with bacteremia and risk factors for death in an intensive care unit. METHOD: 75 patients with 116 episodes of bacteremia were retrospectively studied. RESULTS: The mortality rate of the patients was 43%. Staphylococci (29%), Enterococci (12%), Class I inducible beta-lactamase-producing Enterobacter (12%), extensive spectrum beta-lactamase-producing Enterobacter (10%) were the most common pathogens, among which gram-positive organisms constitute a major part. The most commonly affected organs were respiratory (77%), hepatic (53%), circulatory (53%), gastrointestinal (50%), renal (47%), central nervous (36%), and hemopoietic systems (27%). Multiple organ failure accounted for 76%. Univariate analysis revealed that the severity of underlying illness, multiple organ failure (MOF), septic shock, hepatic failure, renal failure and infection focus were the risk factors for in-hospital death (P < 0.05). Cox proportional hazard model analysis suggested central nervous system failure, septic shock, hemopoietic failure, hepatic failure and respiratory manipulation significantly affected the survival time of patients with bacteremia (P < 0.05). CONCLUSION: Gram-positive organisms are major pathogens of bacteremia in critically ill patients. Antibiotic therapy can not prevent the occurence of bacteremia, nor can it improve the prognosis.

Adult↗