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91.
A 39-year-old woman presented with acute myocardial infarction due to spontaneous dissection of the left anterior descending artery. This was treated conservatively. She had been on combined oral contraceptive pills from the age of 22. Repeat coronary angiography 7 months later revealed spontaneous complete healing.  相似文献   
92.
The purpose of this study is to evaluate the middle-term tonometric results of a new filtering procedure, the nonpenetrating deep sclerectomy with or without collagen device, in primary open-angle glaucoma. This technic aims to eliminate or minimize the complications of classical trabeculectomy. METHOD: This procedure was carried out by Koslov and colleagues. This is performed under a limbal-based conjunctival flap and a superfical scleral flap, the ablation of a deep scleral flap taking away the external wall of Schlemm's canal, only living in place the Descemet membrane. One must obtain a visible filtration across the opened Schlemm's canal and Descemet membrane. To improve the aqueous filtration, a cylindric collagen device, made from porcine scleral tissue, biocompatible, known for its high water content, is fixed in the deep scleral bed with a 10/0 nylon suture. This device provides a support for the elimination route of aqueous humor and acts like a sponge, carrying the liquid by capillary action. It is sterilized by irradiation. Full guarantee against viral contamination is provided. This procedure ends in one suture (10/0 nylon) of superficial scleral flap and conjunctival closing suture. When NPDS is performed without CD a sponge of 5FU is used and the superficial scleral flap is not sutured. RETROSPECTIVE STUDY: Our material included 111 patients, 148 eyes in CD group; 43 patients, 55 eyes in the group without CD. The average follow-up was 13.3 +/- 5.8 months in the CD group, 7.2 +/- 3.5 months in the group without CD. All patients presented a POAG without risk factors of bleb failure. RESULTS: The delta average IOP before the operation and at the end of the follow-up period was 7.2 +/- 6.3 mmHg in the CD group; 8.3 +/- 7.6 mmHg in the group without CD (no significant difference). The probability-success rate with the Kaplan-Meier method (IOP < or = 20 mmHg) was, in the CD group, at 18 months, 68% and 69% in the group without CD, without medical treatment. With monotherapy, the success rate was 85% in the CD group, 74% in the group without CD (p < or = 0.05). PROSPECTIVE STUDY: Afterwards, we have conducted a prospective study comparing two groups of patients with POAG without risk factors of bleb failure, operated with and without collagen device, without 5FU in the second group. Our material included 31 patients, 31 eyes, one eye for each patient, two surgeons; 17 eyes in the CD group, 14 eyes in the group without CD. The average age was 65.8 +/- 8.2 years in the first group; 64.1 +/- 10.3 in the second group. The average follow-up was 11 months in both groups. RESULTS: delta average IOP was 8.3 +/- 5.8 in the CD group; 12.3 +/- 6 in the group without CD (p < 0.05). The probability-success rate without treatment at 12 months: 58% in the first group, 90% in the second group (p < 0.05) and with monotherapy: 80% and 90% (N.S.). In both studies, in both groups, except microperforations, more frequent in the prospective group without CD, no complications of the trabeculectomy were observed. The mean change in visual acuity was inferior to 0.1 at the end of the follow-up. A postoperative rise in IOP can occur. It can be due to an internal obstruction (goniosynechiae or bad filtration). It can be treated with Nd-Yag laser. It can also be due to external obstruction, treated by 5FU injections into the bleb. The success of these procedures were similar in the whole group. CONCLUSION: Non penetrating deep sclerectomy can be considered as an excellent alternative to trabeculectomy in open and wide angles. It does not modify visual acuity. It carries away less complications than trabeculectomy and the use of antimitotic agents is safer. Collagen device does not seem, at middle-term, to improve tonometric results.  相似文献   
93.
Influence of Gypsification on Engineering Behavior of Expansive Clay   总被引:2,自引:0,他引:2  
Volume change in argillaceous sediments can take place due to either swelling of expansive clay or gypsification of anhydrous calcium sulfate. Gypsification offers a variety of serious geotechnical hazards such as high swell pressure, floor heave in tunnels, massive rock uplift in dams, and damages to light structures and pavements. Some of these phenomena have been observed in the Arabian Gulf coastal region, where the behavior of local argillaceous sediments is controlled by severe climatic and environmental conditions. Based on laboratory investigation of natural and synthetic samples, this paper studies the influence of gypsification of anhydrite on the engineering behavior of calcareous expansive clay.  相似文献   
94.
It has been postulated that, in theory, stentless bioprosthetic heart valves provide improved hemodynamics and durability over their stented counterparts. A number of glutaraldehyde modified porcine stentless valves are currently either on the market or in clinical trials. Polyepoxy compound as an alternative cross-linking reagent to glutaraldehyde for bioprostheses has been reported to mitigate calcification. The present study was to investigate the effect of the fixation methods on porcine aortic wall flexibility. Ring specimens were selected from three groups of porcine roots: fresh, low pressure glutaraldehyde fixed, and low pressure Denacol (polyepoxy compound) fixed. Pulled between two rods on a tensile tester, a ring specimen's load-deformation relationship was recorded and analyzed to numerically compute the tissue modulus at low strains. The results showed that the Young's moduli were 0.113 +/- 0.036, 0.494 +/- 0.113, and 1.320 +/- 0.292 MPa (mean +/- SD, n = 10) for the fresh, Denacol fixed, and glutaraldehyde fixed aortic walls, respectively. The Denacol fixed aortic wall was more flexible than the glutaraldehyde fixed one. It was also found that the Denacol fixed aortic wall maintained most of the natural residual strains, while the glutaraldehyde fixed aortic wall did not.  相似文献   
95.
96.
A correct access opening is the key to endodontics. An adequate anatomical access preparation maximizes cleaning, shaping, and obturation. The major objectives of access preparation are straight line access to the apical area, conservation of tooth structure, and unroofing of the pulp chamber. The safe-ended diamond bur technique provides an efficient and rapid means to obtain the objective of access preparation in posterior teeth.  相似文献   
97.
98.
To study the vasopressin receptor domains involved in the hormonal binding, we synthesized natural and modified fragments of V1a vasopressin receptor and tested their abilities to affect hormone-receptor interactions. Natural fragments mimicking the external loops one, two, and three were able to inhibit specific vasopressin binding to V1a receptor. In contrast, the natural N-terminal part of the V1a vasopressin receptor was found inactive. One fragment, derived from the external second loop and containing an additional C-terminal cysteine amide, was able to fully inhibit the specific binding of both labeled vasopressin agonist and antagonist to rat liver V1a vasopressin receptor and the vasopressin-sensitive phospholipase C of WRK1 cells. The peptide-mediated inhibition involved specific interactions between the V1a receptor and synthetic V1a vasopressin receptor fragment since 1) it was dependent upon the vasopressin receptor subtype tested (Ki(app) for the peptide: 3.7, 14.6, and 64.5 microM for displacing [3H]vasopressin from rat V1a, V1b, and V2 receptors, respectively; 2) it was specific and did not affect sarcosin 1-angiotensin II binding to rat liver membranes; 3) it was not mimicked by vasopressin receptor unrelated peptides exhibiting putative detergent properties; and 4) no direct interaction between [3H]vasopressin and synthetic peptide linked to an affinity chromatography column could be observed. Such an inhibition affected both the maximal binding capacity of the V1a vasopressin receptor and its affinity for the labeled hormone, depending upon the dose of synthetic peptide used and was partially irreversible. Structure-activity studies using a serie of synthetic fragments revealed the importance of their size and cysteinyl composition. These data indicate that some peptides mimicking extracellular loops of the V1a vasopressin receptor may interact with the vasopressin receptor itself and modify its coupling with phospholipase C.  相似文献   
99.
OBJECTIVES: Current methods of monitoring chronic synovitis in a single joint rely on clinical examination derived indices, such as the detection of synovial thickening. This study aimed to develop a reproducible method for quantifying the volume of synovial lining in chronic synovitis using contrast enhanced magnetic resonance (MR) imaging. METHODS: The knees of 18 patients with chronic synovitis were examined (34 studies). A 2D T1 weighted FLASH sequence was used to evaluate the temporal enhancement of synovial structures after intravenous contrast. Synovial lining volume was calculated from subtraction of pre and post-enhancement 3D T1 weighted MP RAGE images with thresholding and pixel counting. Eleven patients were examined before and after intra-articular glucocorticoid (mean interval 14 weeks) and MR data compared with changes in clinical examination derived indices of disease activity. RESULTS: Synovial lining volume varied from 52-267 ml. The coefficient of variation in volume calculation was 3.5% for a single observer and was 3.8% for two observers. Synovial lining volume was quantified in all patients where synovial lining thickening could not be detected clinically. A decrease in synovial lining volume of > 40% was associated with an improvement in synovial lining thickening, detected clinically. Decreases in synovial lining volume were quantified by MR in two of three patients where changes in clinical examination derived indices were inconsistent. CONCLUSIONS: A reproducible method of estimating the volume of synovial lining in patients with chronic synovitis has been developed. MR measurement of synovial lining volume may quantify changes in chronic synovitis that remain unidentified by clinical measures.  相似文献   
100.
BACKGROUND: Immunization to platelet alloantigens can occur during pregnancy or after the transfusion of blood components. Platelet alloantibodies can cause neonatal alloimmune thrombocytopenia and posttransfusion purpura. Transfusion-induced alloimmunization to a novel platelet alloantigen system, Gov, expressed on the 175-kDa glycosyl phosphatidylinositol-anchored platelet glycoprotein, CD109, was previously described. This report describes three unrelated patients who were alloimmunized to Gov(a) or Gov(b) during pregnancy. STUDY DESIGN AND METHODS: Platelets were typed by using radioimmunoprecipitation for HPA-1a, -3a, -5a, -5b, Gov(a), and Gov(b) and by polymerase chain reaction-restriction fragment length polymorphism for HPA-1a, -1b, -3a, and -3b. Maternal sera were screened for platelet antibodies by using radioimmunoprecipitation and the antigen capture assay. RESULTS: Patients 1 and 2 were investigated after the diagnosis of neonatal alloimmune thrombocytopenia in their children, and alloantibodies specific for Gov(b) and Gov(a), respectively, were detected in maternal serum. Serum from patient 3, who had mild idiopathic thrombocytopenia purpura with no detectable autoantibody, was found to contain alloantibodies to Gov(b) and to HPA-5b, presumably as a result of immunization during pregnancy. Platelet typings confirmed that the patients were at risk for alloimmunization to the respective antigen. CONCLUSION: This report of three cases of maternal alloimmunization to antigens in the Gov system indicates that immunization can occur via placental transfer of antigen and that Gov system alloantibodies may be associated with neonatal alloimmune thrombocytopenia.  相似文献   
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