Through defining the connotation of division and cooperation among medical institutions, this paper introduces the current status for division and cooperation among medical institutions of Britain, Germany, Singapore and USA. The advantages include excellent general practices, optimal health resource allocation, effective first treat-ment in community health facilities, and effective two-way referral. We analyzed the influence of some new policies on the division and cooperation among medical institutions such as medical association, managed care and the General Practices’ service contract. This provided a lot of experience and revelations, including the dynamics to promote the division and cooperation, the separation of outpatient services and inpatient services, privatization of primary medical institutions, division and cooperation between medical institutions and nursing, rehabilitation institutions, distinguis-hing the division and cooperation from hospitals alliance, and division and cooperation among medical institutions can not resolve the all issues in the medical care supply system.

Aim The kinetics of nicotinic acetylcholine receptor (N-AChR) was stadied. MethodsThe saturation experiments of Torpedo electric organ N-AChR were taken with125I-?-BuTX. The results were calculated by Scatfit program. Experiments were thenperformed to study the kinetics of dissociation of ?-BuTX and nicotine from N-AChR,respectively. When their binding reached saturation, an excess of 1000 times ?-BuTX ornicotine was added. The saturation binding properties of the N-AChR extracted fromleg muscles of the 13th day chick embroys and optic lobes of the 20th day chick em-broys were studied. The results were calculated by Scatfit program. The othe experi-ments were taken to observe the competition between mcotine and 125I-?-BuTX forbinding with Torpedo, optic lobe and skeletal muscle of the chick N-AChRs. ResultsThe saturation experiments of Torpedo electric organ N-AChR resulted in a Scatchardplot of hyperbola which responded to the model of two kinds of receptor with on eli-gand.The difference of and B max between high affinity binding site and low affnitybineing site was significant. The dissaciation experiment showed that the fast dissocia-tion rate of tow ligands was 500 times more than that of the slow dissociation rate. Thisresult suggested that there may be two subtype N-AChRs.The saturation bindingproperties of N-AChR of leg muscles and optic lobe of the chick embroys revealed aScatchard plot of two kinds of N-AChR indicating a single type of site. The bindingaffinity of receptor of optic lobe was 100 times more than that of muscles. In competi-tion for Torpedo receptor by nicotine and 125I-?-BuTX, the values of IC50 were different:which suggested that two kinds of receptor sites were existent. In competition ofNicotine and 125I-?-BuTX for optic lobe and skeletal muscles of the chick N-AChR, thevalue IC50 of skeletal muscles N-AChR was 7. 7 times higher than that of optic lobe. Itindicated that two kinds of N-AChR subtype existed in the optic lobe and in theskeletal muscles of chick respectively. Conclusion N-AChR of Torpedo electric organcontains two kinds of subtype receptors. N-AChR of optic lobe of chick embroys is onesubtype receptor, and N-AChR of skeletal muscles of chick embroy is another subtypereceptor.

Objective To compare the image quality of renal artery in-flow inversion recovery MR angiography (IFIR MRA), CTA and contrast-enhanced MR angiography (CE-MRA) and to assess the value of renal artery IFIR MRA. Methods Thirty five patients were prospectively included in this study.Renal artery CTA was performed in 19 patients and renal artery CE-MRA was performed in 16 patients. In addition to renal artery CTA or CE-MRA, all patients underwent renal artery IFIR MRA. Two radiologists separately graded renal artery image quality, renal venous artifact and the visualization of renal artery branches regarding these three different techniques. Wilcoxon signed rank test of paired samples was used to compare the grading results, t test of paired samples was applied to compare the results of renal artery (accessory renal artery) trunk diameter. The consistency evaluation of renal artery image quality and renal venous artifact grades between two radiologists employed Kappa analysis. Results There was no significant difference between IFIR MRA and CTA with renal artery image quality and renal venous artifact (P>0.05). There was significant difference between IFIR MRA and CE-MRA with renal artery image quality and renal venous artifact (P<0.05). The consistency evaluation results of renal artery image quality and renal venous artifact grades between two radiologists were both good. Kappa value were 0.425 to 1.000. CTA of 19 cases depicted 48 renal arteries (38 renal arteries, 10 accessory renal arteries), IFIR MRA depicted them all. The grades of visualization of renal artery branches about IFIR MRA and CTA were (3.7 ± 0.7) and (3.8 ± 0.6) respectively, renal artery trunk diameter of IFIR MRA and CTA were (4.9 ± 1.3) and (5.0 ± 1.4) mm respectively, there was no significant difference between IFIR MRA and CTA (P>0.05).CE-MRA of 16 cases depicted 38 renal arteries (32 renal arteries, 6 accessory renal arteries), IFIR MRA depicted them all. The grades of visualization of renal artery branches about IFIR MRA and CE-MRA were (3.4±0.8) and (2.5±0.9) respectively, and there was significant difference between IFIR MRA and CE-MRA (Z=-4.040, P<0.01). Renal artery trunk diameter of IFIR MRA and CE-MRA were (4.7±1.3) and (4.7±1.2) mm respectively, there was no significant difference between IFIR MRA and CE-MRA (P>0.05). Conclusions The image quality of renal artery IFIR MRA was equal to CTA and superior to CE-MRA. It could be considered as an alternative technique for renal artery angiography.

Objective To study the efficacy of late course accelerated fractionation(LCAF) radio- therapy in the treatment of nasopharyngeal carcinoma(NPC).The end-po s were local control,radiation-in- duced complications,factors influencing survival.Methods From December 1995 to April 1998,178 NPC patients were admitted for radiation treatment.The radiation beam used was ~(60)Co?or 6 MV X-ray.For the first two-thirds of the treatment,two daily fractions of 1.2 Gy were given to the primary lesion ,with an interval of≥6 hours,5 days per week to a total dose of 48 Gy/40 fractions,over a period of 4 weeks.For the last one third of the treatment,i.e.beginning from the 5th week,an accelerated hyperfractionation schedule was carried out.The dose per fraction was increased to 1.5 Gy,2 fractions per day with an interval of≥6 hours,the total dose for this part of the protocol was 30 Gy/20 fractions over 2 weeks.Thus the total dose was 78 Gy in 60 fractions in 6 weeks.Results All patients completed the treatment.Acute mucosi- tis:none in 2 patients,Grade 1 in 43,Grade 2 in 78,Grade 3 in 52,and Grade 4 in 3 patients.Local control rate:the 5-year nasopharyngeal local control rate was 87.7%,and the cervical lymph node local control rate was 85.7%.The 5-year distant metastasis rate was 26.1%,and 5-year survivals was 67.9%. Sixteen patients had radiation-induced cranial nerve palsy.Conclusions With this treatment schedule, patient's tolerance is good,local control and 5 year survivals are better than control groups of conventional fractionation and hyperfractionation radiotherapy.Radiation-related late complication does not increase.Ran- domized clinical trials are being carried out to further confirm the efficacy of LCAF for nasopharyngeal carci- noma.

Objectives This study aimed at investigating the cellular mechanism of isoproterenol (ISO) on delayed afterdepolarizations (DADs) and triggered activity (TA) of the noninfarcted myocardium in the myocardial infarcted rabbit model.Methods Rabbits with the left anterior descending coronary artery occlusion were prepared and recovered for 8 wk (healed myocardial infarction, HMI). Myocytes were isolated from regions of the noninfarcted left ventricular free wall. ISO was added to cellular surface by perfusion way. Action potentials and ion currents were recorded with whole-cell patch clamp. Results The results showed that treatment with ISO induced more DADs and TA events in HMI myocytes. Iti and ICa-L of myocytes treated with ISO were increased significantly compared with HMI cells, which contributed to DADs-related triggered arrhythmia. Conclusions The results suggested that more arrhythmia events of DADs and TA developed in myocytes with ISO treatment. The underlying mechanism was associated with the augment of Iu and calcium influxing.

Objective To investigate the biofilm (BF)formation rule of nontypeable Haemophilus influenzae (NTHi)in vitro, and to observe the internal structure of BF by scanning electron microscope (SEM). Methods NTHi ATCC49247 was investigated in the present study,Pseudomonas aeruginosa (PA)PAO1 was cultured as positive control,at the same time blank control group was set up.The BF of the bacteria were cultured and then collected on day 1,2,3,4,5,6,and 7.The BF formation was detected by crystal violet staining and plate counting and the structure of BF formed by ATCC49247 was observed under SEM on day 3.Results The plate colony counting of biofilm BF by ATCC49247 and PAO1 raised during first 3 d, and then declined to (0.823 6±0.007 5)×107 cfu·mL-1 and (0.942 6±0.019 9)×107cfu·mL-1 respectively on day 7. The differences between two groups were statistically significant on day 3,4,5,and 6 (P<0.05).The differences between different time points in the same bacteria group were statistically significant (P<0.05).The densities of BF formed by ATCC49247 and PAO1 raised during the first 3 d.The absorbances on 570 nm wavelength (A570 )in two groups were 2.717 4±0.017 2 and 2.885 3±0.039 0 ,respectively;and then the A570 values in two groups declined to 0.151 7±0.074 5 and 1.196 9±1.108 5,respectively on day 7;the differences between bacteria groups and blank control were statistically significant (P<0.05 );the differences between two bacteria groups were statistically significant on day 3,4,5,and 6 (P<0.05);the differences between different time points in the same bacteria group were statistically significant (P<0.05).On day 3,the obvious BF formed by ATCC49247 were observed under SEM.Conclusion BF could be formed by NTHi in vitro;crystal violet staining,plate colony counting and SEM could be taken as conventional methods to detect BF.

Objective To evaluate the effects of astragalus on liver injury and TGF-β1 mRNA expression in immature rats with obstructive jaundice(OJ).Methods Forty immature male Wistar rats were randomly divided into a control,a shamoperation,an OJ,and an OJ+A groups.Wistar rats in the OJ and OJ+A group were subjectedto common bile duct ligation(CBDL),while the sham group had the bile duct mobilized but not tied.The control,sham,and OJ groups were giyen 0.5ml of normal saline by intrapedtoneal injection daily.In the OJ+A group,250mg/100g body weight of astragalus injection was applied intraperitoneally daily from day 1 to 7 of the study.All animals were sacrificed on postoperative day 8.Liver tissue and peripheral blood were colleered.Serum Alanine aminotransferase(ALT),Aspartate aminotransferase(AST),and total cholic acid(TCA)level were detected.Hepatic morphological findings were observed by light microscopy.TGF-β1 mRNA were extracted from liver and measured by reverse transcription polymerase chain reaction(RT-PCR).Data were analyzed using chi-square test and student's test(-x±s),P＜0.05 was considered statistical significance.Results ①Serum AST,ALT,and TCA value in each OJ group were significantly higher than that of the control and sham operation groups.②In the control and sham operation group,normal structure of the liver remained,but in the OJ group,obvious degeneration of hepatocytes was detected,such as cholastasis,starch accumulation and fatty degeneration.Kupffer cells and dilated Disse'space were common in the OJ group.In the OJ group.histopathologic findings of the liver demonstrated intense degree of fibrosis,but in the OJ+A group.typical changes of large duct obstruction were significantly improved after astragalus injection treatment.③The TGF-β1 mRNA over-expression in the OJ group was seen compared with the control and the OJ+A groups.Conclusion ①In growing rat model of experimental obstructive jaundice,hepatic morphology and liver biochemical tests altered significantly.②The administration of astragaius can ameliorate liver damage and diminish expression of TGF-β1 mRNA of hepatic tissue,thus administration of astragalus may be effective in preventing hepatic injury in growing rats with obstructive jaundice.

Objective To study the clinical value of transcervical resection under hysteroscope in treatment of placental remnants.Methods From March 2003 to April 2006,14 cases of placental remnants were treated with transcervical resection under hysteroscope.They included 3 cases of term birth,and 11 cases of midtrimester induction of labor.Drug pretreatment was performed for those who had more than 80 U/L of blood beta-human chorionic gonadotropin (?-hCG) level,including mifepristone (RU486), Chinese herbs and methotrexate(MTX).RU486 was taken orally at 25 mg,three times daily and misoprostol was given 600 ?g at one dose on the third day.MTX was given by deep intramuscular injection at 1 mg/m~2 if ?-hCG was higher than 150 U/L.Bipolar evaporation was used in the operation with alternation of resection and forceps holder under ultrasonographic supervision.After operation a circular contraceptive device was placed followed by hormone periodic treatment such as estradiol valerate for 2-4 months.Results Under the monitoring by ultrasonography,14 operations were all performed smoothly.The follow-up was from 6 months to 2 years.Menstruations in almost all the cases were recovered,and 3 cases of those were pregnant and delivered smoothly 4,6 and 7 months after operation.Conclusion The transcervical resection under hysteroscope is useful in treatment of placental remnants with obvious effects,little trauma and few complications.

AIM: To explore the pathogenesis of aplastic anemia (AA), we identified the crucial isoform of cyclin D that determine the proliferation of the cord blood CD34~+ cells and observed effects of AA serum on the expression of crucial cyclin D isoform in umbilical cord blood CD34~+ cells. METHODS: The CD34~+ cells were isolated with MIDI-MACS system. The isoforms of cyclin D were detected by RT-PCR and Western blotting. Methylcellulose culture system was used to measure the formation of CFU-GM. The expression level of crucial cyclin D isoform was assayed by RT-PCR and Western blotting after the CD34~+ cells were incubated in AA serum. RESULTS: The crucial cyclin D isoform in CD34~+ cells was cyclin D3. The AA serum inhibited the formation of CFU-GM and down-regulated expression level of the cyclin D3 from the mRNA to protein level, respectively. CONCLUSION: The AA serum inhibits the proliferation of CD34~+ cells and down-regulates level of cyclin D3, this may be one of hematopoiesis inhibition mechanisms in AA.

Placentation,which is critical for maternal-fetal exchange of nutrients and gases,is a complicated process comprising stepwise vasculogenesis and angiogenesis.Hypoxia caused by impairedtrophoblast invasion may cause various angiogenic abnormalities in human placenta.The Notchl signaling pathway plays an important role in the regulation of angiogenesis.The angiogenesis of human umbilical vein endothelial cells (HUVECs) under normal/hypoxic conditions and the mRNA/protein level of Notchl/Dell4/Jaggedl were investigated in this study.The effects of DAPT/JAG-1 on the migration of HUVECs were also assessed by cell wound healing assay,so as to discover the possible role of notchl signaling pathway in the angiogenesis of human placenta.The results showed that angiogenic ability of HUVECs was seriously reduced under hypoxic conditions.The mRNA and protein levels of Notchl/Dell4/Jaggedl were decreased in the hypoxic group compared to the control one.In addition,the migration capability of HUVECs was significantly obstructed when treated with DAPT and under hopoxic condition,but promoted when treated with JAG-1.The above results demonstrate that hypoxia downregulates the angiogenesis in human placenta via Notch 1 signaling pathway.