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41.
42.
Aberrant left pulmonary artery, or pulmonary sling, is a rare variation of the pulmonary vasculature, with only one previous report of the condition being recognized in an adult. In this report a second case recognized de novo in an adult is presented. Both of these adults were evaluated because of right paratracheal masses which required differentiation from pulmonary malignancies. The barium swallow shows a characteristic indentation of the anterior esophageal wall and the lateral tomogram demonstrates absence of the left pulmonary artery from its normal position in the left hilum. The pulmonary arteriogram is diagnostic and allows avoidance of more invasive diagnostic measures.  相似文献   
43.
Solid dispersions of naltrexone in natural glycerides were used to form injectable implants which continuously release narcotic antagonists in vivo. The dispersions were formed and tested either as small cylindrical pellets, e.g. l x 3.0 mm in size, or as particles with diameters in size ranges between 125-250 mu, that are suspended in an aqueous methyl cellulose solution. Both types of implants delivered naltrexone to mice at rates that were effective in blocking the antiociceptive action of morphine for at least one month. The rate of naltrexone release was controlled by altering its concentration in the dispersion and by varying the glyceride composition. Degradation and absorption of the implants were found to depend on their composition, dimensions and location in the body. No appreciable tissue incompatibility was seen in mice, rats, rabbits, monkeys and swine, even when long-lasting preparations were removed a year after treatment.  相似文献   
44.
The body's equilibrium is possible thanks to the integration of skeletal structure, vertebrae, ligaments and muscles to form one functional unity. The forces which determine posture are composed of two complementary systems, the ligamentary and the muscular systems, which together determine a dynamic act of balance. The ligaments operate mainly against the visco-hydraulic pressure of the nucleus pulposus and bind the vertebral bodies together, whereas the muscles exhibit an antigravity function and support spinal stability. A mathematical model based on a mixed theory of directed and oriented curves is proposed. Through this model it is possible to develop an exact theory governing the deformation of the ligamentous spine. This theory should be universal in the sense that it can be used to supply the spine in any of its environments.  相似文献   
45.
A small but significant number of tritiated thymidine labelled cells were found, by autoradiography, in the glomeruli of rats with Masugi nephritis or chronic serum sickness nephritis. There were no labelled glomerular cells in sections of untreated animals. The findings favour the contention that in proliferative glomerulonephritis, glomerular hypercellularity is due to infiltration of monocytic cells into the tufts where they divide.  相似文献   
46.
Isotropic material can be made to exhibit piezoelectric effects by the application of a constant electric field. For insulators, the piezoelectric strain constant is proportional to the applied electric field and for semiconductors, an additional out-of-phase component of piezoelectricity is proportional to the electric current density in the sample. The two induced coefficients are proportional to the strain-dependent dielectric constant (depsilon/dS + epsilon) and resistivity (drho/dS - rho), respectively. The latter is more important at frequencies such that rhoepsilonomega less than 1, often the case in biopolymers. Signals from induced piezoelectricity in nature may be larger than those from true piezoelectricity.  相似文献   
47.
48.
This review comprises 36 patients who were treated for Asherman's syndrome from 1968 to 1974 at the Sloane Hospital for Women. Of the 18 patients who later conceived only 6 had uncomplicated term deliveries. Four had premature deliveries resulting in neonatal death. Three had placenta accreta and postpartum hemorrhage, necessitating a cesarean hysterectomy in 1. Two patients required cesarean section for complications due to the syndrome, 2 had spontaneous abortion, and 1 had a cervical pregnancy requiring total hysterectomy. Only 10 babies survived. The incidence and severity of complications in conceptions following treatment for Asherman's syndrome is high, and the obstetrician must be prepared to manage them.  相似文献   
49.
As a first step in the study of the possible relationship between the T/t and H-2 complexes, the H-2 antigenic composition of the strains carrying factors t12, tw32, tw2, tw8, t1, t0, t6, tw1, tw71, tw73, tw12, tw5, tw75, and t38 was studied by using a battery of antisera containing antibodies against inbred-derived H-2 antigens. In addition, five t strains (t12, t6, tw5, tw1, and tw2) were selected for the production of antisera against the H-2 complexes carried by t chromosomes. Spleen, lymph node, and thymus cells from H-2b/t heterozygotes and tw2/tw2 homozygotes were injected into appropriate F1 hybrids between two inbred strains that carried the inbred-derived H-2 antigens of the donor. Four new H-2 antigens and one Ia antigen were uncovered and were assigned the symbols H-2.106 through H-2.109, and Ia.101, respectively. Three new H-2 haplotypes were also described, based upon the H-2 antigenic pattern of three t factors, t12, tw1, and tw5. These new haplotypes were given the symbols H-2t12, H-2tw1, and H-2tw5. When the t factors were grouped according to their H-2 haplotypes, their distribution, with certain exceptions, corresponded to the complementation groups. Thus, t chromosomes in the same complementation group carried similar, if not identical, H-2 haplotypes, despite the fact that these chromosomes were derived from widely separated geographic areas. Such an association between the t and H-2 complexes is most unusual in light of what is known of the polymorphism of H-2 haplotypes in wild mice populations. It suggests more than a casual relationship, at least at the population level, between the t and H-2 loci.  相似文献   
50.
Blood-engorged Culex tarsalis (4,209) collected during 1960 to 1965 in Kern County, California and previously shown to have fed on passeriform birds by the precipitin test were further tested by the more sensitive passive hemagglutination inhibition test (PHI). It was shown that these mosquitoes fed principally on House Finches and House Sparrows, the most common passeriform birds found in the collection areas. These data demonstrate the usefulness of the PHI test for the identification of arthropod blood meals from closely related species.  相似文献   
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