[Dynamic changes of urotensin II receptor in pulmonary artery and arterioles of rats chronically exposed to hypoxia-hypercapnia].

Aim: To investigate the dynamic changes and functions of urotensin II (U lI) receptor (UT) in pulmonary arteries of rats chronically exposed to hypoxia-hypercapnia.

Methods: In rats with hypoxia-hypercapnia at 1, 2 and 4 weeks U II receptor binding of pulmonary arteries sarcolemma was determined by radioligand assay. U II mRNA and UTmRNA in various grades of pulmonary arterioles were measured by in situ hybridization.

[A process and the prospects for the medical geographic study].

Medical geography is an edge subject crossing many other subjects. It has lately become the focus of attention for the continuously worsening of the living surroundings (earth environment) of the human beings and a series of threats it imposes on human health. This text consists of a comprehensive description of the history of medical geography, a detailed introduction of the research work done in China.

Hypoxia-induced expression of HIF-1alpha and its target genes in umbilical venous endothelial cells of Tibetans and immigrant Han.

The better adaptation of native Tibetans to hypoxia is thought to be partly due to improved umbilical circulation, which results in reduced pre- and postnatal fatalities. We hypothesized that the difference in umbilical circulation between native Tibetans and other high-altitude inhabitants was due to differences in the expression of hypoxia-induced factor (HIF-1) and its target genes vascular endothelial growth factor (VEGF) and inducible nitric oxide synthase (iNOS). We tested this hypothesis by examining the effect of hypoxia on the expression of HIF-1alpha, VEGF, and iNOS in cultured umbilical venous endothelial cells (UVECs) from native Tibetans and immigrant Hans.

[Effects of hypoxia on ET and NO levels in cultured umbilical venous endothelial cells of native Tibetan].

Aim: To assay ET and NO in venous blood of native Tibetan and to investigate the effects of hypoxia on ET and NO levels in cultured umbilical venous endothelial cells of native Tibetan.

Methods: ET and NO in venous blood of native Tibetan, immigrant Han and lowland Han were assayed. Umbilical venous endothelial cells (UVECs) from native Tibetan and immigrant Han newborns were cultured and divided into 4 groups: (1) Native Tibetan control group (TC), (2) Native Tibetan hypoxic group (TH), (3) Immigrant Han control group (HC), (4) Immigrant Han hypoxic group (HH).

[Effects of acute hypoxia and adenosine on splenic T-lymphocyte proliferation of rats].

Aim: To observe the effects of acute hypoxia and adenosine on splenic T lymphocyte proliferation.

Methods: Wistar rats were divided into control and hypoxic group, and the latter were exposed to hypoxia (5000 m simulated high altitude, 23 h/d). Three days later, spleen cells were collected and stimulated by 5.

[The role of hypoxic response and breath holding at sea level in prediction of acute mountain sickness].

Aim: To explore whether hypoxic response and breath holding at sea level could predict acute mountain sickness (AMS).

Methods: 113 men aged (19 +/- 1) years took part in this study. Blood oxygen saturation (SaO2), heart rate and blood pressure were measured during the course of breathing 10% O2 for 10 minutes and breath holding.

[Hypoxia promote the DNA synthesis and the expression of collagen type I and III mRNA in cultured adult rat cardiac fibroblasts].

Aim: To observe the effects of hypoxia on DNA synthesis and the expression of collagen type I and III mRNA in cultured adult rat cardiac fibroblasts.

Methods: Cardiac fibroblasts(CFs) were isolated from adult Wistar rat ventricule and cultured in vitro either in normoxic or hypoxic condition. Studies were conducted with the second passage of CFs.

[Hemodynamic effects of aminophylline and nifedipine in patients with high altitude pulmonary edema].

Aim: To evaluate the hemodynamic effects of aminophylline and nifedipine in patients with HAPE.

Methods: 10 patients with HAPE undergone Swan-Ganz catheter. The parameters of hemodynamics and arterial blood gases in HAPE were measured before and after administration of nifedipine 20 mg sublingually and aminophylline 0.

[Effects of hypoxia combined-exercise on blood viscosity and cardiac function of rats].

Aim: To study the effects of hypoxia alone or combined-exercise on blood viscosity and cardiac function of rats.

Methods: 22 wistar rats were divided into 3 groups: I normoxic control; II hypoxia and III hypoxia-combined exercise. Rats of II and III groups were subjected to hypobaric hypoxia for 5 weeks (23 h/day).

[Effect of hypoxia on expression of iNOS mRNA in cultured rat astrocytes].

Aim: To explore the effects of hypoxia on expression of inducible nitric oxide synthase (iNOS) mRNA in cultured rat astrocytes.

Methods: Cultured rat astrocytes were randomly divided into 4 groups: glutamate group (G), hypoxic group (H), hypoxia + glutamate group (H + G) and the control (C). Cells of control group were exposed to normoxic (95% air, 5% CO2) condition, and cells of G and H + G were incubated with 100 micromol/L L-glutamate, cells of H and H + G exposed to hypoxic conditions (5% CO2, 95% N2) at 37 degrees C.

[Relation of the ST-segment elevation pattern in acute phase of anterior wall acute myocardial infarction to short-term prognosis].

Objective: To observe the relation of ST-segment elevation pattern of electrocardiogram (ECG) recorded in acute phase of anterior wall acute myocardial infarction (AMI) to short-term prognosis.

Methods: Sixty-two patients with first anterior wall AMI were divided into 3 groups according to ST-segment elevation pattern in lead V3 of a 12-lead ECG at admission. Patients in group A (n=18) were characterized by concave type of ST-segment elevation, group B (n=27) by straight type and group C (n=17) by convex type.

Changes of plasma adrenomedullin and proadrenomedullin N-terminal 20 peptide concentrations in patients with heart failure.

Objective: To study the changes in plasma adrenomedullin (ADM) and proadrenomedullin N-terminal 20 peptide (PAMP) concentrations and their clinical significance in the pathological process of congestive heart failure (CHF).

Methods: Plasma ADM and PAMP concentrations in 45 patients with CHF (according to the functional classification of New York Heart Association, NYHA) and 20 control subjects were measured by specific radioimmunoassay.

Results: Plasma ADM concentrations were 51.