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1.
Mid- to long-term outcome of disc excision in adolescent disc herniation.   总被引:3,自引:0,他引:3  
BACKGROUND CONTEXT: Adolescent disc herniation and its surgical treatment have been the subjects of many published clinical series. The majority of these series were heterogeneous; the number of adolescent patients (12-17 years) as opposed to young adults (18-20 years) was generally small and the length of follow-up varied greatly. Although the short-term outcome of disc excision in adolescents was mostly favorable, their long-term outcome is unknown. OBJECTIVES: To evaluate the mid- and long-term results of discectomy in patients younger than 17 years of age. STUDY DESIGN: Retrospective examination of a series of adolescent patients under the age of 17 years who underwent surgery for lumbar intervertebral disc herniation. PATIENT SAMPLE: The medical records of 26 patients (15 males, 11 females, 12-17 years old [average 14.6]) who were operated for lumbar intervertebral disc herniation in three spine centers between 1984 and 2002 were reviewed. These subjects represented the total number of patients meeting the criteria of adolescents undergoing discectomy for lumbar disc herniation in these institutions during the study period. All patients were located and contacted by an independent observer not involved in the care of these patients. Low back pain associated with leg pain was the main clinical symptom in 20 patients (77%), leg pain in 4 (15%), and back pain in 2 (8%). They all underwent posterior disc excision: 23 (88%) patients had one level discectomy, and 3 (12%) had simultaneous discectomy at two levels. The L4-L5 interspace was involved 19 times, and the L5-S1 interspace 10 times. Slipped vertebral apophysis was diagnosed in 4 patients (15%). Twelve of the 26 patients (46%) had a first-degree relative with a history of lumbar disc herniation. OUTCOME MEASURES: Telephone interviews provided follow-up data for 26 patients. Results were classified as excellent, good, moderate, or poor according to current symptom status, the need for additional surgery, the Oswestry Disability Index, and back and leg pain scores. RESULTS: The average time from surgery to follow-up was 8.9 years (range 3-21 years). At follow-up, the clinical results were excellent in 13 patients (50%), good in 4 (15%), moderate in 8 (31%), and poor in 1 (4%). Four subjects (15%) underwent a subsequent disc excision in the lumbar region, and one of them later underwent fusion. CONCLUSIONS: Discectomy provides satisfactory clinical results in young patients with disc herniation. The rate of reintervention (15%) is comparable to that in adults, indicating that discectomy for young patients should be approached similarly to that in adults.  相似文献   
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Thyroglossal duct cysts are common congenital abnormalities or developmental field defects, usually detected in early childhood. Despite their frequent occurrence, familial patterns are rare. We report on two new families with thyroglossal duct cysts. In the first family three siblings were involved, while in the second one, father and son were affected. This trait may be autosomal recessive or possibly multifactorial, as the first family would indicate, and also autosomal dominant, as the second family would suggest.  相似文献   
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Objective: To compare the outcome of intracytoplasmic sperm injection (ICSI) with fresh and frozen-thawed testicular spermatozoa in patients with nonobstructive azoospermia.Design: Retrospective analysis of consecutive ICSI cycles.Setting: In Vitro Fertilization Unit, Assaf Harofeh Medical Center.Patient(s): Eighteen with nonobstructive azoospermia in whom testicular sperm was found after testicular sperm extraction.Intervention(s): Testicular sperm retrieval, cryopreservation, and ICSI with fresh or frozenthawed testicular spermatozoa.Main Outcome Measure(s): Two-pronuclear fertilization; embryo cleavage rates, mean number of embryos transferred per cycle, and their relative quality, embryo implantation, clinical pregnancy, and ongoing pregnancy rates (PRs) per ET.Result(s): No statistically significant differences were noted in all parameters examined between ICSI cycles with fresh or cryopreserved testicular spermatozoa from the same nine patients and comparing all ICSI cycles performed; with fresh (25 cycles) and thawed (14 cycles) testicular spermatozoa, respectively: two-pronuclear fertilization, 47% versus 44%; embryo cleavage rates, 94% versus 89%; implantation rates, 9% versus 11%; and clinical PR, 26% versus 27%. The delivery or ongoing PR using fresh sperm was better (21% versus 9%), but the difference did not reach statistical significance. The cumulative clinical PRs and ongoing PRs per testicular sperm extraction procedure were 36% and 24%, respectively.Conclusion(s): Testicular sperm cryopreservation using a simple freezing protocol is promising in patients with nonobstructive azoospermia augmenting the overall success achieved after surgical sperm retrieval. (Fertility Sterility 1997;68:892-7. C 1997 by American Society for Reproductive Medicine.)  相似文献   
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In heart failure, a deficient oxygen supply often is a primary cause for myocardial dysfunction. The reverse however, may also be true; the changes that occur in the failing heart may predispose for the existence of tissue hypoxia, which further affects the function of the heart. Specifically, myocardial hypertrophy and accelerated heart rhythm enhance oxygen demand, while supply is hampered short by endothelial dysfunction and diffusion barriers (such as fibrosis, arterial hyperplasia, and myocyte hypertrophy). Another contributory factor may be deficient growth of the microvasculature that does not keep pace with the rate of myocardial hypertrophy. Fewer microvessels have been observed in many forms of cardiomyopathies. On the other hand, some distinct forms of cardiomyopathies are characterized by the compensatory growth of microvessels, or even excess angiogenesis. This review summarizes the knowledge that has been gathered on this topic thus far and discusses factors that mediate myocardial microvessel growth. Furthermore, a paradigm is presented in which the rate of microvessel growth predicts, at least in part, the degree of myocardial dysfunction. Therapies aimed at the restoration of the microcirculation are proposed to preserve and improve myocardial function.  相似文献   
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Matricellular proteins are extracellular matrix proteins that modulate cell-matrix interactions and cell function, and do not seem to have a direct structural role. The family includes tenascin-C (TN-C), tenascin-X (TN-X), osteonectin, osteopontin, thrombospondin-1 (TSP1) and thrombospondin-2 (TSP2). Expression of matricellular proteins is high during embryogenesis, but almost absent during normal postnatal life. Interestingly, it re-appears in response to injury. Left ventricular remodeling is a complicated process that occurs in the stressed heart, and is still not completely understood. Several members of the matricellular protein family, like tenascin-C, osteopontin, and osteonectin are up-regulated after cardiac injury. Therefore, this group of proteins may have crucial functions in the heart coping with stress. This review will focus on the expression, regulation and function of these matricellular proteins, and will discuss the crucial functions that these proteins might exert during remodeling of the stressed heart.  相似文献   
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PURPOSE: To characterize the flow dynamics of albumin ultrasound contrast microspheres containing perfluoropropane (PFP) in normal and inflamed microvasculature. MATERIALS AND METHODS: Mesenteric microvessels of rats were examined after an intravenous injection of fluorocein-labeled erythrocytes or PFP microspheres by fluorescence intravital microscopy with and without local application of 10(-8) M platelet activating factor (PAF) as an experimental form of inflammation. RESULTS: All the microspheres passed freely through arterioles and capillaries. Mean velocities of the microspheres in each vessel were closely correlated with those of erythrocytes. Only a minor fraction of the microspheres was retained in the venules (> or =0.1 s stoppage) by attachment to endothelial cells. The frequency of microsphere retention in venules was significantly enhanced by PAF (2.6+/-2.1%, P<0.01 vs. control), especially in regions with leukocyte adhesion. Treatment with a monoclonal antibody to intercellular adhesion molecule-1, P-selectin or the common leukocyte antigen inhibited PAF-induced microsphere retention in venules (P<0.05). In the inflamed microcirculation, a small subgroup of microspheres becomes attached to venular endothelial cells in regions with leukocyte adhesion via interaction among microspheres, activated leukocytes and endothelial cells via adhesion molecules. CONCLUSION: In inflamed microcirculation, a small subgroup of microspheres becomes attached to venular endothelial cells in regions with leukocyte adhesion via interaction among microspheres, activated leukocytes and endothelial cells via adhesion molecules. These results suggest that ultrasonography with microspheres has the potential to evaluate inflammatory site distribution as well as tissue perfusion.  相似文献   
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