Objective To study the influence of interim overload exercise on health and it's biochemical mechanism.Methods 45 Wistar rats were randomly divided to three groups(n=15):no exercises group(control,C),normal exercise group(NE,the rats ran in the animal running machines at 15 m?min-1for 5 d in one week,exercise time was 30 min?2,and rested for 10 min after ran for 30 min),overload exercise group(OE,the rats exercised 2 bouts,2 d in consecutive in one week,exercise time was 100 min?2,and they rested for 10 min after ran for 100 min).After training for 8 weeks,the rats in three groups were sacrificed and 15 biochemical indexes in blood of rats were determined.Results Compared with C and NE groups,CK,LDH,and ALT increased obviously(P

Magnetic bearing has no mechanical contact between the rotor and stator. And a rotary pump with magnetic bearing has therefore no mechanical wear and thrombosis due to bearing. The available magnetic bearings, however, are devised with electric magnets, need complicated control and remarkable energy consumption. Resultantly, it is difficult to apply an electric magnetic bearing to rotary pump without disturbing its simplicity, implantability and reliability. The authors have developed a levitated impeller pump merely with permanent magnets. The rotor is supported by permanent magnetic forces radially. On one side of the rotor, the impeller is fixed; and on the other side of the rotor, the driven magnets are mounted. Opposite to this driven magnets, a driving motor coil with iron corn magnets is fastened to the motor axis. Thereafter, the motor drives the rotor via a rotating magnetic field. By laboratory tests with saline, if the rotor stands still or rotates under 4,000 rpm, the rotor has one-point contact axially with the driving motor coil. The contacting point is located in the center of the rotor. As the rotating speed increases gradually to more than 4,000 rpm, the rotor will detache from the stator axially. Then the rotor will be fully levitated. Since the axial levitation is produced by hydraulic force and the driven magnets have a gyro-effect, the rotor rotates very steadly during levitation. As a left ventricular assist device, the pump works in a rotating speed range of 5,000-8,000 rpm, the levitation of the impeller hence is ensured by practical use of the pump.
Equipment Design ; Heart-Assist Devices ; Magnetics ; instrumentation

For long-term application of the rotary pumps, it is necessary to solve the problems of bearing wear and thrombosis along the bearing. Currently, many investigators choose the magnetic bearing to realize zero-friction and no contact between the rotor and stator; the former avoids the mechanical wear and the latter eliminates the possibility of thrombus formation. We tried and found that it is difficult to apply a magnetic bearing to rotary pump without disturbing its simplicity, reliability and implantable; therefore, we have developed a much simpler and much more creative approach to achieving the same results. Instead of the sliding bearing, a rolling bearing has been devised for the pump; its friction is about 1/15 of the sliding bearing. Furthermore, a wear-proof material of ultra-high-molecular weight polythene has been adopted in making the rollers, their anti-wear property in 8 times better than that of metal. Thereby, the service life of the bearing has extended to several years. For preventing the thrombus formation along the bearing, the impeller reciprocation axially as the impeller changes its rotating speed periodically to produce a pulsatile flow. The reciprocation is a result of the effects of a magnetic force between the motor rotor and stator, and a hydraulic force between the blood flow and the impeller. Similar to piston pump, the oscillating impeller can make the blood in and out of the bearing, resulting in wash-out once a circle. This is obviously beneficial to preventing thrombosis along the bearing and in the pump. The endurance tests with saline of this novel pump demonstrated a durability of the device. It promises to be able to assist the circulation of the patients permanently and to be able to replace the heart transplantation in the future.
Heart-Assist Devices ; Magnetics ; instrumentation ; Prosthesis Design ; Thrombosis ; prevention & control

To evaluate the effect of impeller design on pump hemolysis, five impellers with different number of vanes or different vane angles were manufactured and tested in one pump for hemolysis comparison. The impellers are made to have the same dimension and same logarithmic spiral vane from which coincide with the stream surfaces in the pump, according to the analytical and three-dimensional design method developed by the authors. Consequently, an impeller with 6 vanes and 30 degrees vane angle has the lowest hemolysis index. This result agrees with the theoretical analyses of other investigators searching optimal number of vanes and vane angle to achieve the highest efficiency of the pump.
Heart-Assist Devices ; adverse effects ; Hemolysis ; Humans ; In Vitro Techniques ; Prosthesis Design

The author's implantable pulsatile impeller pump can assist the circulation of the calves for several months. The termination of the experiments was related to wear of the mechanical bearing, which resulted in vibration of the rotor and pump failure. It seemedas if the experiments could have lasted inde finitelyif the bearing had not failed. To solve the problem of bearing wear, a specially devised rolling bearing was investigated and applied to the impellerp ump. Its service life is more than 10 years due to the wear-proof roller made of ultra-high-molecular weight polythene. This newly devised impeller heart promises to have long-term and permanent applications. Compared with the magnetic bearing, the rolling bearing has the advantages of simpler construction and control, no consumption of energy, and better reliability.

Objective: To explore the prognostic value of the international prognostic index (IPI), the national comprehensive cancer network IPI(NCCN-IPI)and the age-adjusted IPI (aa-IPI) in diffuse large B cell lymphoma. Methods: A total of 311 patients with de novo diffuse large B-cell lymphoma (DLBCL) diagnosed from 2003 to 2012 in Nanfang hospital were included. All patients were divided into CHOP (cyclophosphamide, vincristine, doxorubicin, and prednisone) and R-CHOP (rituximab, CHOP) groups. Survival analysis was compared among IPI, NCCN-IPI and aa-IPI models. Discrimination of three different prognostic models was assessed using the Harrell’s C statistic. Results: A total of 311 patients were analyzed. Among them, 128 patients were treated with CHOP regimen and other 183 patients were treated with R-CHOP regimen. In CHOP groups, both NCCN-IPI (5-year OS: 59.7% vs 26.8%, P<0.001) and aa-IPI (5-year OS: 71.0% vs 25.0%, P<0.001) showed better risk stratification for low-intermediate and high-intermediate group than the IPI (5-year OS: 47.6% vs 36.6%, P=0.003). However, in the patients treated with R-CHOP, NCCN-IPI showed better risk stratification in low, low-intermediate, high-intermediate groups (5-year OS: 96.0% vs 83.0% vs 66.5%, P=0.009). According to the Harrell’s C statistic, C-index of IPI, NCCN-IPI and aa-IPI for overall survival (OS) were 0.546, 0.667, 0.698 in CHOP group and 0.611,0.654, 0.695 in R-CHOP group respectively. In patients younger than 60 years old, C-index of IPI, NCCN-IPI and aa-IPI for OS were 0.534, 0.675, 0.698 in CHOP group and 0.584, 0.648, 0.695 in R-CHOP respectively. Conclusion The NCCN-IPI is more powerful than IPI and aa-IPI in DLBCL patients receiving R-CHOP. aa-IPI is a preferable model in predicting prognosis than IPI and NCCN-IPI in anthracycline-based chemotherapy without rituximab.