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21.
Coracoid fractures are rare injuries which may be easily missed radiographically. This case report discusses a 14 year old child who sustained a coracoid fracture during a violent tackle whilst playing rugby. The fracture was clearly visible only on the axial view of the shoulder, and was subsequently confirmed by CT scan. This article includes a discussion detailing the anatomy and developmental features of the coracoid process of the scapula, its clinical significance, and radiological assessment of suspected coracoid injury. 相似文献
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Decreased expression of phospholipase C-beta 2 isozyme in human platelets with impaired function 总被引:4,自引:4,他引:4
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function. 相似文献
24.
Signal transduction on platelet activation involves phosphoinositide- specific phospholipase C (PLC)-mediated hydrolysis of phosphatidylinositides and formation of inositol-1,4,5-triphosphate [I(1,4,5)P3], which mediates Ca2+ mobilization, and diacylglycerol (DG), which activates protein kinase C (PKC) to phosphorylate a 47-kD protein (Pleckstrin). We studied these events in two related patients previously reported (Blood 74:664, 1989) to have abnormal aggregation and 14C-serotonin secretion, and impaired intracellular Ca2+ mobilization in response to several agonists. Thrombin-induced I(1,4,5)P3 and phosphatidic acid formation were diminished. Pleckstrin phosphorylation was impaired on activation with thrombin, platelet- activating factor, and ionophore A23187, but was normal with PKC activator 1,2-dioctonyl-sn-glycerol (DiC8). Ca2+ mobilization induced by guanosine triphosphate (GTP) analog guanosine 5'-0-(3 thiotriphosphate) (GTP gamma S) was diminished. Pretreatment with either A23187 or DiC8 did not correct the impaired adenine diphosphate- induced secretion; however, upon stimulation with A23187 plus DiC8, pleckstrin phosphorylation and secretion were normal, indicating that both PKC activation and Ca2+ mobilization are essential for normal secretion. We conclude that these patients have a unique inherited platelet defect in formation of two key intracellular mediators [I(1,4,5)P3 and DG] and in the responses mediated by them due to a defect in postreceptor mechanisms of PLC activation. 相似文献
25.
Immunoglobulin V regions and the B cell 总被引:7,自引:2,他引:7
26.
Anita Mahapatra A. R. Aramya R. Manohar K. Latha 《Indian journal of pharmaceutical sciences》2015,77(5):650-654
Kaṣāya or decoction is an Ayurvedic dosage form, prescribed based on the stage of the disease according to the principles of Ayurveda. This dosage form is traditionally prepared fresh and consumed on the same day but for the sake of convenience; the process of preparation has been modified so that it can be stored with longer shelf life, easy availability and produced in large quantities. There is a need to understand the implications of this modification in terms of chemical changes. This work attempted to check the phytochemical profile of both freshly prepared decoction and commercially available decoction with reference to some analytical parameters like pH, total soluble solids, phenols, alkaloids, potassium and to assess the changes in the thin layer chromatography profiling of the decoction. The results showed that phenols and potassium are found to be two fold higher in freshly prepared decoction, compared to commercially available decoction diluted to dosage in practice (1:4 ratio). However, the total alkaloid content was found to be approximately ten fold higher in commercially available decoction. It was observed that the thin layer chromatography profile of decoctions was extracted into petroleum ether and chloroform was similar and consistent with different batches though the bands in commercially available decoction were slightly more intense compared to freshly prepared decoction. The total soluble solids in commercially available decoction were four times higher than freshly prepared decoction. The study reveals that there are differences in the phytochemical profiles of the freshly prepared decoction and commercially available decoction of the same formulation. However, the significance of these differences can be determined only by further clinical studies. On the other hand, the study lends support to the practice of diluting the commercially available decoction to make it equivalent to freshly prepared decoction. 相似文献
27.
28.
Acquired granular pool defect in stored platelets 总被引:1,自引:0,他引:1
Platelets stored as concentrates (PC) for 72 h at 22 degrees C develop a functional defect. Alterations in adenine nucleotides of platelets have been shown to affect platelet function. Adenine nucleotide content of platelets was measured before and after storage and a decrease of 27.1 /+- 1.7% (mean /+- SE) in ATP and 39.1 /+- 2.6% in ADP were found in 34 PC stored with final volume of 50 ml. In 11 PC with 30 ml volume. ATP and ADP decreased by 39.4 /+- 3.2% and 49.4 /+- 2.1%, respectively. The mean ATP to ADP ratio of stored platelets was significantly higher than of fresh platelets in both groups, suggesting a relatively greater decrease in granular than metabolic pool nucleotides. Levels of low affinity platelet factor 4 measured by radioimmunoassay in plasma from 0.86 /+- 0.08 microgram/ml in the fresh PC to 8.59 /+- 0.39 microgram/ml in stored PC, indicating a concomitant alpha-granular secretion. Labeling of metabolic pool with 14C-adenine revealed a mean decrease in the adenylate energy charge of 2.0 /+- 0.4% in 12 of 16 stored PC, with a lower ATP and higher hypoxanthine labeling in stored as compared to fresh platelets. These observations suggest that stored platelets develop an acquired defect in both dense and alpha granules and in their ability to maintain ATP homeostasis. 相似文献
29.
Bryant Lin Paul J. Wang Srijoy Mahapatra Munther Homoud Mark Link N.A. Mark Estes Amin Al‐Ahmad 《Annals of noninvasive electrocardiology》2005,10(2):142-145
Background: Morphologic identification of ectopic P‐waves from surface ECGs can be challenging, particularly when the P‐wave is buried in the QRST wave complex. Because ECGs are often available on paper and not digitally, we developed a method of subtracting the T‐wave from the buried P‐wave complex on paper ECGs. Methods: To validate our system, an atrial extrastimulus was introduced during and following the T‐wave. The ECGs were scanned and then transformed from an image format to a digital format. A computer algorithm digitally subtracted a QRST with no buried P‐wave from one with a buried P‐wave, thus resulting in an extracted P‐wave. The extracted P‐waves were compared to the nonburied P‐wave by determining correlation coefficients and by visual grading by two independent reviewers. Results: Visual grading comparing the buried P‐wave with the exposed paced P‐wave was 94%. The median correlation coefficient was 85%. Conclusions: An ectopic atrial P‐wave obscured by a coincident QRST wave complex can be accurately derived from printed ECG using this PC‐based system. Addition of this technique to the existing methods may aid in the localization and ablation of ectopic atrial foci. 相似文献
30.
Patients with mitral valve disease and extreme enlargement of the left atrium usually exhibit significant decrease in chamber size following corrective mitral valve surgery. We describe a patient in whom extreme right and left atrial enlargement developed, and progressed following mitral valve replacement, with no evidence of prosthetic valve malfunction or tricuspid valve disease. 相似文献