At present, Chinese medical field faces with an important problem of how to correctly handle the relationship between medical and scientific research. Academician Li Lianda advocates doctors doing scientific research under the premise of putting the medical work first. He points out that there are many problems in the process of doctors doing scientific research at present such as paying more attention to scientific research than medical care, excessively promoting building scientific research hospital, only paying attention to training scientific talents, research direction be flashy without substance, the medical evaluation system should be improved and so on. Medical, scientific research and teaching are inseparable because improving medical standards depends on scientific research and personnel training. But not all doctors need to take into account of medical treatment, scientific research and teaching in the same degree while not all hospitals need to turn into three-in-one hospital, scientific research hospital or teaching hospital. It must be treated differently according to the actual situation.
Altitude ; Biomedical Research ; education ; manpower ; trends ; Humans ; Physicians ; psychology ; statistics & numerical data

Objective To investigate the potential effect of hypoxia on adhersion and invasion of human cervical carcinoma cells HeLa. Methods Reverse transcription-polymerase chain reaction (RT-PCR) was used to investigate the level of HIF-1? mRNA and E-cadherin mRNA of HeLa cells cultured under normoxia, 5%O2, 3%O2, 1%O2. The invasiveness of HeLa cells was investigated by transwell chamber assay. Results Under the condition of normoxia, 5%O2, 3%O2 and 1%O2, the optical density ratio of HIF-1? mRNA/?-actin was (0.423?0.116), (0.764?0.111), (1.687?0.126) and (0.215?0.099), showing that the level of HIF-1? mRNA had a tendency of first inceasing and then decreasing with the decreasing oxygen content. The optical density ratio of E-cadherin/?-actin was (1.045?0.171), (0.719?0.114), (0.386?0.105) and (0.157?0.063), showing a decreasing tendency with the decreasing of oxygen content. The invasiveness of HeLa cells was (112.5?20.7), (254.3?27.5), (333.6?45.2) and (124.5?24.6), showing that the invasiveness of HeLa cells had a tendency of first inceasing and then decreasing with the decreasing oxygen content. Conclusion Moderate hypoxia up-regulates the mRNA levels of HIF-1?, and down-regulates the mRNA levels of E-cadherin, and enhances the tumor invasiveness. The possible mechanism is the increasing mRNA levels of HIF-1?.

BACKGROUND:Some researches demonstrate that bone mineral density of healthy males and females whose ages range from 20 to 40 years reaches the peak.With the age growing,bone mineral density decreases gradually so as to cause osteoporosis.OBJECTIVE:To analyze changes of bone mineral density and characteristics of osteoporosis in 289 healthy middle and old aged people in two communities,Dongcheng district,Beijing.DESIGN:Cross-sectional study.SETTING:Beijing Institute of Geriatrics,Beijing Hospital,Ministry of Health.PARTICIPANTS:A total of 289 healthy residents over 45 years old were randomly selected from two communities,Dongcheng district,Beijing from June to September 1998.There were 136 males and 153 females,and their ages ranged from 45 to 85 years.Exclusion criteria:① Hepatic and renal disfunction;② effects of various factors on bone metabolism (various acute and chronic diseases;histories of long-term administration of hormone and calcium preparation;19 kg/m2＞index of body mass＞28 kg/m2;long-term bed over three months;unusual occupation).All subjects provided the confirmed consent.METHODS:Dual-energy X-ray bone density meter (Lunar Company,USA) was used to measure bone mineral density of all subjects at proximal end of left femur (neck of femur,great troch,Ward's triangle) and antero-posterior position of lumbar spine (L2-4).Diagnostic criteria of osteoporosis set by WHO and peak bone value acquired from a tackle key program were used to determine diagnostic standards of osteoporosis at various sites.The diagnostic standards were detailed as follows:neck of femur:0.665 g/cm2 of males and 0.677 g/cm2 of females;great troch:0.598 g/cm2 of males and 0.506 g/cm2 of females;Ward's triangle:0.492 g/cm2 of males and 0.514 g/cm2 of females;L2-4:0.760 g/cm2 of males and 0.835 g/cm2 of females.Meanwhile,peak bone value acquired by Key Program During the Ninth Five-Year Plan Period was used to calculate bone mineral density losing rate and prevalent rate of osteoporosis.MAIN OUTCOME MEASURES:Bone mineral density,bone mineral density losing rate and prevalent rate of osteoporosis at various sites in patients with the two sexes.RESULTS:All 289 subjects were involved in the final analysis.① With the age growing,bone mineral density in the males was not increased obviously;however,decrease of bone mineral density and bone mineral density loss in the females were remarkable,especially over 55 years old.② Analysis of bone mineral density losing rate based on various sites:bone mineral density losing rate in both males and females ranged Ward's triangle＞neck of femur＞great troch＞L2-4.③ Prevalent rate of osteoporosis was increased gradually with the age growing;especially,that in the females was obviously higher than that in the males,and there was significant difference (P＜ 0.01).Osteoporosis highly occurred in femur,and then in Ward's triangle and L2-4.CONCLUSION:With the age growing of the females,osteoporosis easily onsets in neck of femur,Ward's triangle and L2-4;especially menopause is the main risk factor for osteoporosis.

Objective To study the acute inhalation toxicity of 50% Luowei,a plant molluscacide,in rats. Methods Twenty adult Wistar rats,half male and half female,were given of 5000 mg/m3 of 50% Luowei through a dynamic inhalation de?vice and the death and recovery of the rats were observed within 14 days,and LC50 was drawn. Results After exposure,the ac?tivities of the rats decreased and a few individual animals had scratching symptom,but the symptom disappeared after the expo?sure. No animals died during the whole observation period. Therefore,the acute inhalation LC50 was greater than 5000 mg/m3 for rats,and Luowei belonged to low toxicity level. Conclusions 50% Luowei will not cause animal death if it is inhaled into ani?mal body. However,people still need to wear protective equipment in production and use.

The effect of Taurine ( Tau)on 45Ca influx of isolated left ventricular muscles in rats has been investigated. The 45Ca influx of the preparations untreated with Tau, are affected by the concentrations of calcium in KH solution. when the concentration of calcium is 0.62; 1.25; and 1.87mmol/L respectively, the 45Ca influx is 1.02? 0.25; 1.37?0.14 and 1.45?0.14 ?mol/g wet tissue, respectively. After adding Tau, the situations above were changed significantly. It was shown that is 1.11 ? 0.11, 1.45?0.12, and 1.48 ? 0.09 ?mol/g wet tissue in low Ca2?; 1.19?0.07, 1.14 ? 0.23, and 0.97?0.24 ?mol/g wet tissue in normal Ca2?; and 1.12?0.05,0.58?0.18 and 0.53?0.10 ?mol/g wet tissue in high Ca2? treated with Tau 10, 20, and 40 mmol/L, respectively. The results show that the varied ,Ca2? concentrations in KH solution can affect 45Ca influx of cardiac muscles, but Taurine has a bisphasic modulation o,f calcium influx in the same tissue. The effects of modulating calcium may play an important role for anti-arrhythmic mechanism of Taurine.

Objective To evaluate the efficacy of PTCRA+ PTCA in patients with complicated coronary disease Methods PTCRA+PTCA were performed on 16 lesions in 14 patients in our hospital Results In 14 lesions, PTCA was performed after direct PTCRA in order to achieve opital angigraphic result; PTCRA was performed in 5 coronary artery lesions after failed PTCA 14 patients (100%) had successful result Conclusion The combined use of PTCRA+PTCA can improve the success rate during revasculrization for patients with complicated coronary artery disease

Purpose　The aim is to immobilize the thrombin and to increase the stability of immobilized enzyme.Methods　Thrombin was immobilized on chitosan and crosslinked with glutaraldehyde, and the optimum conditions for immobilization and stability of immobilized enzyme were studied.Results　This preparation of immobilized thrombin was practicable,and the stability of this immobilized enzyme was obviously improved than that of thrombin.Conclution　The conditions for immobilization were good, and reliable.Stability of immobilized thrombin to light, high temperature,low temperature and observation on reserving at room temperature was good.

Objective To observe the changes in secretory functions of cultured umbilical vein endothelial cells injured by serum from pregnancy induced hypertension (PIH). Methods Endothelial cells isolated from the umbilical veins from moderate or severe PIH women (PIH group, n =10) and normal pregnant women (control group, n =8) were incubated at 37 ℃ in humidified air with 5% CO 2. Cell culture fluids were obtained at 3 and 4 d of primary culture. Contents of nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), lactate dehydrogenase (LDH ) in the cell culture fluids were measured. Results LDH activity and MDA contents in the cell culture fluids in PIH group were significantly higher than those in the control group ( P

Graphite ; Humans ; Spectrophotometry, Atomic ; methods ; Vanadium ; urine