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L Q Yu

Publications and source records attributed to L Q Yu.

6 recordsLinked to original sources
PubMed2001

Study of the spectrophotometric analysis of protein solution with p-iodochlorophosphonazo as adsorbate by the microphase adsorption-spectral correction technique.

A microphase adsorption-spectral correction (MPASC) technique was established, which consists of Langmuir adsorption and the spectral correction technique. The hypothesis of a microelectric field formed in macromolecules is proposed, the existence of which results in the adsorption and aggregation of dye molecules in macromolecules. This paper describes the spectrophotometric analysis of protein solution with p-iodochlorophosphonazo (p-ICPA) dye. The results showed that the adsorption ratios of p-ICPA to proteins (bovine serum albumin, ovalbumin, myoglobin and gamma-globulin) at pH 2.56 were 54, 25, 14 and 90, respectively, their adsorption constants 2.86 x 10(5), 1.42 x 10(6), 2.38 x 10(5) and 1.09 x 10(5) and their absorptivities 8.00 x 10(5), 4.02 x 10(5), 1.77 x 10(5) and 1.15 x 10(6) l mol-1 cm-1 at 620 nm. The analysis of practical samples showed that the recovery of protein was between 92.3 and 108% and the relative standard deviation was 4.7%.

Absorption↗
PubMed2000

[Clinical research on arteriovenous internal fistula made by various blood vessels].

OBJECTIVE: To compare the permeability and incidence rate of complication of arteriovenous internal fistula made by autogenous, homologous, and artificial Teflon blood vessels. METHODS: Two hundred and forty one cases with arteriovenous internal fistula made by autogenous, homologous, and artificial Teflon blood vessels were followed up to compare the permeability and incidence rate of complication at 6 months, 1 year, 3 years, and 5 years. RESULTS: The incidence rate of complication of autogenous blood vessels was lowest, it had no statistical differences compared with arteriovenous internal fistula made by homologous blood vessels. The permeability of arteriovenous internal fistula made by homologous blood vessels was highest, and it had no statistical differences compared with autogenous blood vessels. The permeability of arteriovenous internal fistula made by artificial Teflon blood vessels was lowest, but the incidence rate of complication was highest, and it had significantly statistical differences compared with arteriovenous internal fistula made by autogenous blood vessels (P < 0.01). CONCLUSION: Arteriovenous internal fistulas made by autogenous and homologous blood vessels have high permeability and low incidence rate of complication, they are superior to the arteriovenous internal fistula made by artificial Teflon blood vessels.

Adolescent↗
PubMed1984

New sequential external counterpulsation for the treatment of acute myocardial infarction.

Over a period of 6 years, 52 patients with acute myocardial infarction (AMI) were treated with sequenced external counterpulsation (SECP). Of the 23 patients who experienced severe chest pain, 22 had complete relief within 30 min of SECP, and 31 of the 52 patients showed remarkable improvement in their electrocardiogram after the first hour of treatment. Fifteen patients were studied using the 35-lead ST segment elevation-mapping method. sigma ST and NST, indicators of infarct size, showed decreasing trends in seven patients treated with SECP for a period of 6 days, whereas sigma ST and NST of the control group of eight patients increased during the same period. Our hemodynamic data indicate that in four of five patients with AMI and left heart failure, the central venous pressure and cardiac output increased after SECP, whereas the pulmonary wedge pressure decreased. Measurements of the P-wave terminal force of lead V1 also demonstrated that the application of SECP can improve left ventricular function in a majority of patients with AMI.

Adult↗
PubMed1983

Sequential external counterpulsation (SECP) in China.

A new SECP was developed and is currently successfully used in more than 120 clinics in China. This sequenced counterpulsation device has the effect of milking more blood as pressure is applied on the extremities in succession (first distally then proximally) and in decreasing values (265 to 200 mm Hg). In comparison of the 4 types of counterpulsation, namely nonsequenced leg and 4 limb counterpulsation, and sequenced 4 limb and 4 limb with buttock balloons, the SECP with buttock balloons method raised the DA to appreciably higher levels with respect to DA amplitude and area. DA was raised 43.9% higher than that obtained with 4 limb SECP alone. From our experimental and clinical results, we conclude that SECP with buttock balloons is a far more effective method providing greater diastolic augmentation than previously reported in the literature. Two hundred angina and 52 AMI patients who had undergone the SECP treatment constitute the basis of this report. The present work represents an analysis of 6 yrs experience with studies on the design, development and clinical evaluation of the SECP method. Ninety-seven percent of the angina patients obtained long-term symptomatic relief. Relapse was minimal. In 95.7% of the AMI patients chest pain or shock symptoms were rapidly relieved. SECP with high DA appears to be very effective in improving myocardial blood supply and ventricular function. Moreover, the simplicity and advantages of this noninvasive sequenced counterpulsation method have been reported (1063 cases) from 31 clinics in China. This method is convenient, safe, and far more effective than conventional drug therapy for patients with acute and chronic ischemic myocardial disease.

Angina Pectoris↗