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101.
102.
Clinical and biological data were evaluated using Desu univariate analyses or Cox multivariate analyses in a series of 1,777 chronic lymphocytic leukemia (CLL) patients from an Italian Cooperative Group. In univariate analyses, age and sex of patients, presence of bone marrow (BM; greater than or equal to 50%), and peripheral blood (PB; greater than or equal to 60,000/microL) lymphocytosis, anemia (hemoglobin [Hb] less than 11 g/dL), thrombocytopenia (less than 100,000/microL), direct Coombs' test positivity, hepatomegaly, splenomegaly, and extent of lymph node involvement were shown to be of significant prognostic value. Multivariate analyses, through a stepwise procedure, showed that the most important prognostic variables are Hb, hepatomegaly, lymph node involvement, PB lymphocytosis, and age and sex of patients. Further covariates would produce an improvement having a nonsignificant P value. Based on the results of multivariate analyses, a four-step staging using the significant variables of the Cox model is proposed.  相似文献   
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105.
Physiology and pathophysiology of skeletal muscle contractions   总被引:4,自引:0,他引:4  
An overview is presented of the physiology and pathophysiology of dynamic skeletal muscle contractions in the intact living organism. Dynamic muscle activities are divided into concentric contractions with shortening of muscle fibres and the production of positive work, and eccentric contractions with lengthening of muscle fibres and the production of negative work. In positive work, muscle tension overcomes external forces. In negative work, external forces overcome muscle tension. The latter phenomenon, with relatively few active motor units, explains the injuries induced by eccentric contractions. Both the contractile and non-contractile elements are involved in the muscle injuries and, clinically, they are referred to as myofibrositis.  相似文献   
106.
In a vertically slotted 0.022 X 0.028 inch edgewise system, the use of a two-dimensional ribbon arch--0.022 X 0.016 inch from lateral incisor to lateral incisor and 0.016 X 0.022 inch from the canine to the molars--plus an uprighting spring on the canine maintained incisor position while unilaterally protracting a molar-premolar unit by means of sliding mechanics. Five degrees of labial crown torque was placed in the incisor portion of the wire and the uprighting spring exerted a force of 200 to 250 g. The intra-arch force applied to protract the molar--premolar unit was 300 to 350 g.  相似文献   
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108.
The two stage gravimetric technique used for the measurements of industrial aerosols, in combination with measurements of mass-related concentrations of particles in the air, provided major hygienic information on the sizes (dispersity) of the inhaled particles. The results of the measurements taken in various branches of industry, ore and alluval deposit mines clarified the fundamental properties of the particles' distribution into rough and thin fractions. An express two-stage gravimetric technique for determining ore aerosol dispersal contents was proposed, along with the technical characteristics of the USSR-produced dust counters.  相似文献   
109.
Gestational age determination based on obstetric dating criteria, early pregnancy ultrasound scans, Dubowitz examinations, and ultrasound scans performed shortly before delivery were reviewed for 69 preterm infants requiring neonatal intensive care. The last ultrasound scans underestimated gestational age by a median of 8 days, and by 2 weeks or more in 20 of the 69 cases, as opposed to best dating criteria. Ultrasonic fetal weight estimation was more accurate, but erred by more than 20% in 10% of cases. When obstetric decisions regarding preterm neonates must be made without prior information regarding gestational age, late ultrasound findings must be applied with extreme care.  相似文献   
110.
Experience in the treatment of 129 patients with esophagogastric hemorrhage due to portal hypertension is discussed. An original modification of the design of Blakemore's tube is suggested, with the use of which the results of nonoperative treatment were improved and the mortality among this category of patients was reduced. Operation was performed on 75 patients. The total mortality among all hospitalized patients was 6.2%. The Tanner-Petrov operation was carried out on 55 patients, splenorenal anastomosis was formed in 6, organopexy was conducted on 4, splenectomy in combination with organopexy in 8, and portocaval anastomosis was formed in 2 patients. Three patients died after the operation.  相似文献   
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