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排序方式: 共有411条查询结果,搜索用时 46 毫秒
1.
P B Dobrin P H Gully H B Greenlee R J Freeark R Moncada R Churchill C Reynes R Henkin 《Archives of surgery (Chicago, Ill. : 1960)》1986,121(1):41-46
A review was made of the charts of 94 patients who underwent ultrasonography (US), computed tomography (CT), and gallium citrate Ga 67 (Gall) scan to rule out intra-abdominal abscesses. Of all the clinical and laboratory data, only the presence of pain and tenderness differentiated patients with and without abscesses. A review of radiologic data showed that CT was superior to US, and that US was superior to Gall scan with regard to sensitivity, specificity, accuracy, and positive and negative predictive values. When multiple radiologic tests were performed, results agreed in 72% of cases; therefore, the additional tests were essentially redundant. When radiologic test results disagreed, accuracy rates were CT, 0.86; US, 0.00; and Gall scan, 0.44. These findings suggest that, except to rule out pelvic abscesses in the presence of pelvic inflammatory disease, CT is usually the only special radiologic test that should be performed to localize a suspected intra-abdominal abscess. 相似文献
2.
Some mechanical properties of polypropylene sutures: relationship to the use of polypropylene in vascular surgery 总被引:1,自引:0,他引:1
P B Dobrin 《The Journal of surgical research》1988,45(6):568-573
This study was performed to examine some mechanical properties of Polypropylene sutures. Fifty segments of 3-0, 4-0, 5-0, 6-0, and 7-0 sutures were mounted in clamps and were subjected to stepwise elongation. Results showed that suture stiffness (elastic modulus) and breaking stress (tensile strength) correlated directly and linearly with the circumference or "skin" of the filaments and inversely with the cross-sectional area or "core" of the filaments. These data suggest that the strength of the suture may reside in the outer skin. These findings are related to the handling of Polypropylene in surgery, and to suture motion in grafts in patients. 相似文献
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4.
Kiril Nenov Alexander Stoyanov Dobrin Paskalev 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2005,9(5):A39-A39
Over the last decades, plasma exchange (PE) has been applied in the treatment of over 150 different diseases including nephrological, hematological, neurological, and rheumatological. Clinical benefit has been demonstrated in only about 40 of them and the best results were achieved in diseases with pathogenic autoimmune mechanisms. We used PE most frequently in patients with immune and autoimmune nephropathies aiming to decrease pathologically elevated antibody levels, autoantibodies and immune complexes. PE was applied in 40 patients with chronic glomerulonephritis, 29 patients with lupus nephritis, and 9 patients with Schoenlein‐Henoch nephritis. After 3 to 4 PE sessions, continuous immunosuppressive drug therapy was initiated. Significant reduction of antibody titers and immune complexes was achieved. PE was also applied in 45 plasmacytoma patients with nephropathy to reduce plasma viscosity and slow down the progression of myeloma nephropathy. The result was a significant reduction of pathologically elevated plasma viscosity and a detoxification effect. In our clinic plasma exchange procedures were performed by either centrifugal method with Haemonetics M‐30 device or by plasma filtration. An average of 1316 mL plasma was removed during a PE session. For substitution purposes donor plasma and saline solutions were used. Clinical remission was achieved in 61.3% of all patients without slowing the progression of renal failure, however. 相似文献
5.
One of the main problems of treatment of bifurcation lesions is side branch (SB) stenosis appearing after stent placement in the main vessel.The aim of this study was to create quantitative method for prediction of side branch compromise extent.We accepted that the main mechanism for SB ostial stenosis is flow divider (FD) displacement from stent struts after stent implantation in the main vessel.Using easily measurable parameters from coronary angiography,as SB diameter,angle α (initial angle between axes of parent vessel and SB axis) and angle α' (angle between above mentioned axes after stent placement) we can calculate percentage diameter stenosis at branch ostium (%DS):%DS = sin (α - α')/(tan α).In boundary condition of full FD displacement %DS = cos α.We tested our theoretical predictions with fluoroscopic observation of elastic wall model of bifurcation (45°distal angle between branches)permitting wall deformations with stent.There is full coincidence of values of %DS and percentage area stenosis (%AS).The regular formulas for calculations of %DS and %AS overestimate stenosis severity between 10% and 25%.Our model tests have shown full coincidence between predicted values for %DS and observed values.We demonstrate that part of the SB ostium is not visible in regular angiography and contributes to ostial lumen area.This is a method that permits quantitative prediction of side branch compromise. 相似文献
6.
Targeted inactivation of αi2 or αi3 disrupts activation of the cardiac muscarinic K+ channel, IK+Ach, in intact cells
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Margaret O. Sowell Chianping Ye Dennis A. Ricupero Sherry Hansen Stephen J. Quinn Peter M. Vassilev Richard M. Mortensen 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(15):7921-7926
Cardiac muscarinic receptors activate an inwardly rectifying K+ channel, IK+Ach, via pertussis toxin (PT)-sensitive heterotrimeric G proteins (in heart Gi2, Gi3, or Go). We have used embryonic stem cell (ES cell)-derived cardiocytes with targeted inactivations of specific PT-sensitive α subunits to determine which G proteins are required for receptor-mediated regulation of IK+Ach in intact cells. The muscarinic agonist carbachol increased IK+Ach activity in ES cell-derived cardiocytes from wild-type cells, in cells lacking αo, and in cells lacking the PT-insensitive G protein αq. In cells with targeted inactivation of αi2 or αi3, channel activation by both carbachol and adenosine was blocked. Carbachol-induced channel activation was restored in the αi2- and αi3-null cells by reexpressing the previously targeted gene and guanosine 5′-[γ-thio] triphosphate was able to fully activate IK+Ach in excised membranes patches from these mutants. In contrast, negative chronotropic responses to both carbachol and adenosine were preserved in cells lacking αi2 or αi3. Our results show that expression of two specific PT-sensitive α subunits (αi2 and αi3 but not αo) is required for normal agonist-dependent activation of IK+Ach and suggest that both αi2- and αi3-containing heterotrimeric G proteins may be involved in the signaling process. Also the generation of negative chronotropic responses to muscarinic or adenosine receptor agonists do not require activation of IK+Ach or the expression of αi2 or αi3. 相似文献
7.
Previous research has demonstrated sex differences in face processing at both neural and behavioural levels. The present study examined the role of handedness and sexual orientation as mediators of this effect. We compared the performance of LH (left-handed) and RH (right-handed) heterosexual and homosexual male and female participants on a face recognition memory task. Our main findings were that homosexual males have better face recognition memory than both heterosexual males and homosexual women. We also demonstrate better face processing in women than in men. Finally, LH heterosexual participants had better face recognition than LH homosexual participants and also tended to be better than RH heterosexual participants. These findings are consistent with differences in the organisation and laterality of face-processing mechanisms as a function of sex, handedness, and sexual orientation. 相似文献
8.
Polyspecificity is defined as the ability of a given antibody molecule to bind a large panel of structurally diverse antigens. A fraction of circulating IgG in all healthy individuals acquires promiscuous antigen-binding activity only after a transient exposure to certain protein destabilizing factors. The molecular mechanisms of this phenomenon are not well understood. Exposures to protein destabilizing agents are common steps in immunoglobulin isolation and purification processes. We performed kinetic and thermodynamic analyses using surface plasmon resonance-based technique in order to characterize the interactions of a single mouse monoclonal antibody to its cognate antigen before and after induction of promiscuous antigen-binding activity. The obtained results, suggest that enhanced antigen binding activity induced by exposure to mild denaturing condition resulted from an increase in the structural flexibility of the antigen-binding site. Further pH and ionic strength-dependence analyses of the antibody/antigen interactions demonstrated that the transition to promiscuous antigen-binding was accompanied by a change in the type of non-covalent forces involved in the complex formation. Moreover, from this study, it is evident that an antibody molecule could use two distinct thermodynamic pathways for binding to the same antigen while retaining the same value of the binding affinity. The obtained results may contribute to the understanding of the molecular mechanisms that lay behind natural antibody polyspecificity. 相似文献
9.
Selective silencing of DNA-specific B lymphocytes delays lupus activity in MRL/lpr mice 总被引:1,自引:0,他引:1
Tchorbanov AI Voynova EN Mihaylova NM Todorov TA Nikolova M Yomtova VM Chiang BL Vassilev TL 《European journal of immunology》2007,37(12):3587-3596
The pathological DNA-specific B lymphocytes in lupus are logical targets for a selected therapeutic intervention. We have hypothesized that it should be possible to suppress selectively the activity of these B cells in lupus mice by administering to them an artificial molecule that cross-links their surface immunoglobulins with the inhibitory FcgammaIIb surface receptors. A hybrid molecule was constructed by coupling the DNA-mimicking DWEYSVWLSN peptide to a monoclonal anti-mouse FcgammaRIIb antibody. This chimeric antibody was added to cultured spleen cells from sick MRL/lpr mice, immunized with diphtheria toxoid, resulting in reduction of the numbers of anti-DNA but not of anti-diphtheria IgG antibody-producing cells. Intravenous infusions with the DNA-peptide antibody chimera to 7-wk-old animals prevented the appearance of IgG anti-DNA antibodies and of albuminuria in the next 2 months. The administration of the DNA-peptide chimeric antibody to 18 wk-old mice with full-blown disease resulted in the maintenance of a flat level of IgG anti-DNA antibodies and in delay of the aggravation of the lupus glomerulonephritis. The use of chimeric antibodies targeting inhibitory B lymphocyte receptors represents a novel approach for the selective suppression of autoreactive disease-associated B cells in autoimmune diseases. 相似文献
10.
The process of incorporating insulin pumps into the everyday lives of people with Type 1 diabetes: A critical interpretive synthesis
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Claire Reidy MSc Mike Bracher PhD Claire Foster PhD Ivaylo Vassilev PhD Anne Rogers PhD 《Health expectations》2018,21(4):714-729