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1.
The beStent is a new stainless steel, balloon-expandable mesh stent which has a unique serpentine design. Rotation of the unique low stress junctions upon expansion leads to orthogonal locking of the wires, maximizing radial strength and assuring zero shortening. The stent has delineating gold markers which assure precise positioning. We aim to present the initial acute results in a pilot registry for stent evaluation. Two hundred eighty-four stents were used in a total of 217 patients (age 57.9 ± 3.10 years; 178 males; 39 females) in seven centers, for variable indications. Stents of 15-, 25-, and 35-mm length were used. The arteries treated were the left anterior descending (n = 112, 42%), circumflex (n = 54, 20.2%), right coronary (n = 95, 35.5%), left main (n = 1, 0.4%), and vein graft (n = 5, 1.9%). Lesion types were: A in 42 patients (16.5%); B1 in 53 patients (20.7%); B2 in 81 patients (31.8%); and C in 79 patients (31%). One hundred fifty-nine patients required one stent, 40 patients required two stents, and 18 patients required three or more stents. Anticoagulation protocol included procedural heparin with aspirin with/without ticlopidine. Smooth angiographie results were obtained in all cases with no plaque herniation. Acute angiographic success was obtained in 97% of the patients, and acute clinical success in 95% of the patients. Complications within 30 days were: 3 deaths (1.4%) (2 noncardiac); 2 (0.9%) myocardial infarctions; and 2 (0.9%) stent thromboses. Therefore, the beStent is useful in treatment of complex lesions of variable length and complexity, providing excellent acute results with a low complication rate, in spite of unfavorable basic clinical and angiographie characteristics.  相似文献   
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Alterations of the immune system following splenectomy in childhood   总被引:1,自引:0,他引:1  
After splenectomy due to blunt abdominal trauma, splenectomized children showed a restricted pattern of T-cell immunodeficiency compared to age and sex-matched normal children. Peripheral blood total (CD3) T-cell counts of 11 splenectomized children of 43%, double positive helper (CD4) inducer subpopulation (CD29) cell counts of nine splenectomized children of 7%, and phytohemagglutinin (PHA)-induced T-cell proliferation of 11 splenectomized children of 53,206 c.p.m. were significantly (p less than 0.05) lower than values of normal children (61% CD3 cells, n = 12; 13% CD4CD29 cells, n = 11; 107,832 c.p.m. PHA-induced proliferation, n = 12). The deficit of CD4CD29 cell numbers may be due to impaired maturation of these particular CD4 lymphocytes and may explain diminished PHA-induced proliferation in small children. The significantly higher B-lymphocyte counts of splenectomized children (21%, n = 11; 558 cells/mm3, n = 10) compared with 12 normal children (14%; 329 cells/mm3) may be due to loss of the reservoir function of the spleen.  相似文献   
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Zusammenfassung Schwere Gallengangsverletzungen sind nach laparoskopischen häufiger als nach konventionellen Cholezystektomien zu beklagen. Sie resultieren meist aus technischen Problemen oder unzureichender Identifikation der entsprechenden Strukturen. Das sofortige Erkennen der Gallengangsverletzung ist fur eine entsprechende Therapie ebenso wichtig wie die ädequate chirurgische Technik, die angewendet wird. Hier wird eine neue Methode der Gallenwegrekonstruktion unter Verwendung eines Jejunalkonduits vorgestellt. Das Verfahren wurde bislang bei 5 Patienten mit schweren Gallengangsverletzungen (Typ 3 and 4 nach Bismuth) [2] nach laparoskopischer Cholezystektomie erfolgreich angewendet. Der Verlauf nach nunmehr 9 Monaten bis zu mehr als 2 Jahren war ohne Probleme and vielversprechend. Die Methode der Anwendung des Jejunalkonduits erscheint uns zur Rekonstruktion bei schweren Gallengangverletzungen sehr empfehlenswert.
A new technique for reconstruction of the common bile duct after severe injury by laparoscopic cholecystectomy
Laparoscopic cholecystectomy involves a higher incidence of severe common bile duct injury than did open cholecystectomy. The severe injuries most often result from technical problems and inadequate exposure. Reconstruction of the bile duct is then possible provided that an immediate diagnosis is made and an appropriate surgical technique is applied. The report focuses on a new method of reconstruction of the common bile duct by interposition of a small jejunal conduit. The procedure was performed in five patients with severe bile duct injury (Bismuth class 3–4) that occurred during laparoscopic cholecystectomy. The outcome after follow-up periods of 9 months to more than 2 years is promising. This method of reconstruction is therefore recommended for severe forms of bile duct injury.
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5.
This paper describes a specific and highly sensitive ELISA system using monoclonal antibodies in order to assay an organophosphorus compound. The soman derivative methyl phosphonic acid, p-aminophenyl 1,2,2,-trimethyl-propyl diester (MATP) served as model substance. In order to obtain antibody-producing hybridomas BALB/c mice were immunized with MATP linked onto human serum albumin (HSA). The spleen cells of immunized mice were fused with syngenic plasmacytomas of the non-producer-line X63Ag8.653 with the aid of polyethylene glycol. To eliminate undesirable cross-reaction, common screening procedures were modified by directly coating the ELISA plates with hapten. Five out of 15 positive cell-lines were cloned by limiting dilution and further propagated. The respective immunoglobulin class and subclass of the obtained monoclonal antibodies was determined. Four of which were identified as IgG1, the other as IgG2a. After enrichment of antibodies in ascites and their isolation by protein A-sepharose, the affinity of various monoclonal antibodies was estimated in competitive inhibition enzyme immunoassay (CIEIA) by measuring the IC50 rates of free MATP. The rates were found to lie between 2.5 × 10–6 mol/l and 4.3 × 10–4 mol/l MATP. The IC10 rate for detectable MATP concentration was 5.4 × 10–7 mol/l MATP. Test duration was 280 min. The reactivity of the monoclonal antibodies with structurally related substances was used to check their specificity. Cross-reaction turned out to be negative. In order to develop a direct competitive ELISA, MATP was linked to horse radish peroxidase (HRPO) by adding a spacer. This helped to reduce total duration to 40 min. The detection level was further reduced to 1.3 × 10–7 mol/l MATP (corresponding to 975 pg/25 l test-buffer) using the monoclonal antibody F71D7. Likewise, MATP was detected in goat serum, chicken serum, rabbit serum, milk and company's water in concentrations between 2.1 × 10–7 mol/l (IC10, company's water) and 4.9 × 10–8 mol/l (IC10, milk).  相似文献   
6.
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.   相似文献   
7.
Injection of soluble protein antigen into the anterior chamber of the eye of primed mice induces anterior chamber-associated immune deviation (ACAID) which is manifested by suppression of delayed-type hypersensitivity (DTH) to the antigen. Recently, we found that ACAID induced in primed mice also results in a rapid rise in serum of soluble T lymphocyte-derived proteins specific for nominal antigen (TABM). Here, we demonstrate that serum TABM induced in primed mice during ACAID will transfer the suppression of DTH to mice primed to the same antigen. Sera from TNP-BSA-primed mice that received an anterior chamber injection of TNP-BSA, but not BSA alone, suppressed the DTH response to TNP when injected into other TNP-BSA-primed mice. Sera absorbed with Sepharose beads conjugated with either anti-TCR C(alpha), anti-TCR C(beta), anti-TABM or TNP-BSA did not contain TNP-specific TABM and did not transfer suppression of DTH. These results suggest that the antigen-specific, TCR C(alphabeta)+ TABM that appear in serum during ACAID are able to confer on or amplify the capacity of sensitized T cells to suppress DTH. We believe this to be the first demonstration of an in vivo immunologic function that is specifically associated with TABM produced in vivo.   相似文献   
8.
In search for a possible explanation of the phenotypic heterogeneity in IgA deficiency, we studied the function of B cells from IgA-deficient (IgAd) individuals. Two groups of IgAd individuals, one frequently infected and one clinically apparently healthy, as well as normal controls, were studied. Peripheral blood mononuclear cells (PBMC) and B cells from IgAd individuals and controls were cultured with Staphylococcus aureus Cowan I strain and with anti-CD40 MoAb presented on the CD32-transfected fibroblast cell line in the presence of IL-10. In this experimental system PBMC and B cells from the infection-prone IgAd individuals produced only minute amounts of IgA. In contrast, PBMC and B cells from healthy IgAd subjects secreted significantly more IgA1 and IgA2 in comparison with infection-prone IgAd patients (P < 0.05). These data suggest that the abnormalities of B cell differentiation in IgAd could be of heterogeneous origin. Thus, whereas in healthy IgAd subjects IgA production may be efficiently up-regulated in vitro by addition of IL-10 to CD40-activated B cell culture, the corresponding B cell differentiation does not occur in infection-prone IgAd patients. These observations provide a conceptual framework for phenotypic heterogeneity in IgAd subjects.  相似文献   
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The nitric oxide pathway in pre-eclampsia: pathophysiological implications   总被引:2,自引:0,他引:2  
Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with NG-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined.  相似文献   
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