The location, shape and internal architecture of the sinoatrial node (SAN) were studied histologically in serial section in 15 hearts (7 adults, 8 foetuses). Based on our observation, the human SAN may be divided into four layers, namely, (1) thesinoatrial node artery layer: its outer longitudinal muscular layer of its media partly lacked in the SAN concentrically; (2) the periarterial layer: the cells of this layer surround the artery concentrically; (3) the central layer, making up the main mass of the node: most P cells in which are arranged parallel to the node artery. In adult the diameter of P cells in this layer is 5.18 ?m; (4) the peripheral layer: most transitional cells in this layer radiate from SAN into the atrial muscle. These "tongues of transitional cells" extend mostly into right atrial-muscle and a few into the musculature of superior vena cava. The diameter of transitional cells of this layer in the adult is 7.28 ?m. In the adult the arrangement of dense collagen fibers appears circular in the periarterial layer, longitudinal in the central layer and radiative in the peripheral layer. According to the location, layers of sinoatrial node and the arrangement of the connective tissue, the functional significance and morphological basis of the re-entry are discussed.

OBJECTIVETo evaluate the effects of thermal and mechanical cycling on the metal-ceramic bond strength of machine-milled Ti2448 alloy and commercial pure titanium (cp Ti).

METHODSCeramic-cp Ti (n = 30) specimens and ceramic-Ti2448 combinations (n = 30) were prepared in accordance with ISO 9693. The specimens from each metal-ceramic combination were randomly divided into three subgroups. In group A or the control group, the specimens were only stored in distilled water for 24 h at 37 °C; in groups B and C, the specimens were subjected to 3,000 cycles of thermal cycling between 5 and 55 °C for a dwell time of 60 s and to mechanical cycling of 20,000 or 40,000 cycles with 50 N load and 4 Hz in distilled water at 37 °C. A crack initiation test was performed using a universal testing machine in accordance with ISO 9693. Failure types at the metal-ceramic interface and the morphological and elemental composition of this interface were analyzed using a scanning electron microscope and an energy dispersive spectrometer. Statistical analysis was performed via two-way ANOVA and Tukey's adjustment test (α = 0.05).

RESULTSThe bond strength of the ceramic-Ti2448 combination was significantly higher than that of the ceramic-cp Ti combination regardless of fatigue conditions (44.86 MPa ± 1.75 MPa and 29.21 MPa ± 2.20 MPa for Ti2448 and cp Ti, respectively; P < 0.01). The mean bond strengths of ceramic-cp Ti and ceramic-Ti2448 combinations in group C were significantly lower than that of group A (P < 0.01). Although ceramic-cp Ti combination failed adhesively at the metal-ceramic interface without the ceramic on the substrate surface, Ti2448 frameworks exhibited cohesive failure; as a result, large amounts of residual porcelain were retained on the specimens.

CONCLUSIONThe metal-ceramic bond strength of cp Ti and Ti2448 is decreased by thermal and mechanical cycling.

100 kDa respectively. \ \{Conclusion\ Eight\} protein bands out of 26 soluble antigen bands of the parasite showed high immunogenicity. There were 9 main polypeptide spots in 43 polypeptide spots of the parasite.

Objective To investigate the expression and distribution of leptin in pre-implantation embryo,and its effect on mouse embryo development in vitro. Methods Adult NIH female mice were superovulated and then mated with fertile males of the same strain. On the morning of 1st to 4th d of pregnancy,the oviduct and horn of uterus were dissected out and flushed with DMEM/F12 medium adequately. The embryos collected were subjected to the following procedures: ①Total RNA was isolated from embryos of each stage respectively and mRNA expression of leptin was detected by RT-PCR. ②Immunofluorescence staining was performed on blastocysts to analyze the expression and the distribution of leptin protein under laser confocal microscope. ③Eight-cell embryos were cultured in medium containing leptin antibody at various concentrations to observe the formation and hatching of blastocysts. Results ①Leptin mRNA expression was only detected in blastocyst,and no expression was detected in embryos in other stages. Leptin protein was detected in cytoplasma,membrane of trophoblastic cell and inner cell mass,however no expression was detected in cell nucleus. ②Leptin polyclonal antibody significantly inhibited formation of blastocysts (1∶400,P

Animals ; Drug Combinations ; Drugs, Chinese Herbal ; chemistry ; pharmacokinetics ; pharmacology ; Humans ; Research Design

Primary biliary cirrhosis (PBC)is characterized by injury of small intrahepatic bile ducts,but its mechanism,especially the role of B cell immunity in this disease,remains unclear.The possible role of B cell immunity in the pathogenesis of PBC is reviewed from the fol-lowing aspects:distribution of B cells and plasma cells in the liver tissues of PBC patients,clearance of B cells,mechanism of abnormal in-crease in serum IgM and its sources among PBC patients,mechanism of production of antimitochondrial antibodies and their possible func-tions in bile duct injury,and typical autoantibodies in PBC.B cell immunity is considered to play a significant role in the pathogenesis of PBC,but there are still many key problems to be clarified.

OBJECTIVE:To obverse the efficacy and safety of Liuwei dihuang pill combined with TCM prescription acupoint application in the treatment of type 2 diabetic constipation. METHODS:120 patients with type 2 diabetic constipation were random-ly divided into control group(60 cases)and observation group(60 cases). All patients received controlling blood pressure and regu-lating blood lipids drugs,diet control combined with exercise,and fixed dose of Metformin hydrochloride tablet(0.5 g/times,2 times a day)and Acarbose tablet(100 mg/times,3 times a day);based on it,control group received 5 mg Mosapride citrate tablet, 3 times a day;observation group additionally received 8 Liuwei dihuang pills(3 times a day)combined with TCM prescription acu-point application (in double Tianshu Point,double Yongquan point,double Shenque Point and double Zusanli). 7 d was regarded as a treatment course,and it lasted 3 courses. Clinical efficacy,blood glucose [2 h postprandial glucose(2 h PG),blood glucose (FPG)],the clinical symptom indexes(defecation interval time,each defecation time,weekly defecation frequency)before and af-ter treatment,and the incidence of adverse reactions in 2 groups were observed. RESULTS:The total effective rate in observation group was significantly higher than in control group,and the difference was statistically significant (P<0.05). Before treatment, there were no significant differences in the 2 h PG,FPG,defecation interval time,each defecation time and weekly defecation fre-quency between 2 groups(P>0.05). After treatment,2 h PG and FPG in 2 groups were significantly lower than before,and obser-vation group was lower than control group;defecation interval time and each defecation time were significantly shorter than before, and observation group was shorter than control group;weekly defecation frequency was significantly higher than before,and obser-vation group was higher than control group,The differences were statistically significant (P<0.05). During treatment,6 patients showed adverse reactions in control group,and 5 in observation group,and there was no significant difference in the incidence of adverse reactions between 2 groups(P>0.05). CONCLUSIONS:Liuwei dihuang pill combined with TCM priscription acupoint ap-plication shows good efficacy in the treatment of type 2 diabetic constipation. It can effectively improve constipation,reduce defeca-tion interval time and each defecation time,increase weekly defecation frequency and have no influence on blood glucose control with small adverse reactions and high safety.

Objective To study the therapeutic effect and mechanism of Jiawei Xiaochengqi Decoction on hepatic injures by endotoxin in rats. Methods Endotoxemia model of Wistar rats was made by thioacetamide. Blood biochemistry and pathological changes were examined to observe the effect of Jiawei Xiaochengqi decoction on liver function, TNF-?, endotoxin of the model rats. Results Jiawei Xiaochengqi Decoction could reduce the contents of TNF-?, endotoxin in the blood and the degree of hepatic cells necrosis of Wistar rats. There was significant difference compared with model group (P

Objective To observe the clinical effect of Shiwei Wendan Decoction on coronary heart disease stable angina pectoris of qi deficiency and stasis-phlegm type. Methods Sixty patients of stable angina pectoris which belonged to the type of qi deficiency and stasis-phlegm were divided randomly into the treatment group and the control group,and each group has 30 cases. The treatment group was given Shiwei Wendan Decoction and the control group was given Tongxinluo Capsule for 4 week,one course. The changes of symptoms integral,ECG,clinical efficacy,blood-fat and CRP of the two groups were observed after the treatment. Results The total effective power of the treatment group was higher than that of the control group (P