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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   
2.
Internal totality and community orientation are two pivotal components, difficult to measure, in the literature on residential education (including both residential schools for the elite and group or congregate care and education programs for marginal youth). We propose a two-dimensional model based on historical research and contemporary study to define and differentiate these concepts. Internal totality can be measured through the links and balance between the formal curriculum, extra curriculum, and out of school (nonformal) activities; community orientation through links between the residential and ideological community, the local community, and the wider community. Implications for practice, policy, and further research are suggested.Oranim is the School of Education of the Kibbutz Movement, affiliated with the University of Haifa.  相似文献   
3.
Systemic lupus erythematosus (SLE) is a multisystem disease of unknown origin, characterized by a variety of autoimmune phenomena. Viruses have long been postulated to play a role in its pathogenesis. Several observations suggested a link between Epstein-Barr virus (EBV) and SLE. We describe a 14-year-old girl who presented with acute onset of SLE concurrently with clinical and laboratory findings consistent with EBV-induced infectious mononucleosis (IM). Evidence for acute EBV infection was confirmed by serological studies and detection of specific EBV antigens on kidney biopsy. This close association between EBV and SLE suggests a possible role of the virus in the pathogenesis of SLE in this patient.  相似文献   
4.
5.
Dynamic mechanical conditioning is investigated as a means of improving the mechanical properties of tissue-engineered blood vessel constructs composed of living cells embedded in a collagen-gel scaffold. This approach attempts to elicit a unique response from the embedded cells so as to reorganize their surrounding matrix, thus improving the overall mechanical stability of the constructs. Mechanical conditioning, in the form of cyclic strain, was applied to the tubular constructs at a frequency of 1 Hz for 4 and 8 days. The response to conditioning thus evinced involved increased contraction and mechanical strength, as compared to statically cultured controls. Significant increases in ultimate stress and material modulus were seen over an 8 day culture period. Accompanying morphological changes showed increased circumferential orientation in response to the cyclic stimulus. We conclude that dynamic mechanical conditioning during tissue culture leads to an improvement in the properties of tissue-engineered blood vessel constructs in terms of mechanical strength and histological organization. This concept, in conjunction with a proper biochemical environment, could present a better model for engineering vascular constructs. © 2000 Biomedical Engineering Society. PAC00: 8719Rr, 8714Ee, 8718-h, 8768+z  相似文献   
6.
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   
7.
OBJECTIVE: Garlic (Allium sativum) has been suggested to affect several cardiovascular risk factors. Its antiatherosclerotic properties are mainly attributed to allicin that is produced upon crushing of the garlic clove. Most previous studies used various garlic preparations in which allicin levels were not well defined. In the present study, we evaluated the effects of pure allicin on atherogenesis in experimental mouse models. METHODS AND RESULTS: Daily dietary supplement of allicin, 9 mg/kg body weight, reduced the atherosclerotic plaque area by 68.9 and 56.8% in apolipoprotein E-deficient and low-density lipoprotein (LDL) receptor knockout mice, respectively, as compared with control mice. LDL isolated from allicin-treated groups was more resistant to CuSO(4)-induced oxidation ex vivo than LDL isolated from control mice. Incubation of mouse plasma with (3)H-labeled allicin showed binding of allicin to lipoproteins. By using electron spin resonance, we demonstrated reduced Cu(2+) binding to LDL following allicin treatment. LDL treatment with allicin significantly inhibited both native LDL and oxidized LDL degradation by isolated mouse macrophages. CONCLUSIONS: By using a pure allicin preparation, we were able to show that allicin may affect atherosclerosis not only by acting as an antioxidant, but also by other mechanisms, such as lipoprotein modification and inhibition of LDL uptake and degradation by macrophages.  相似文献   
8.
BACKGROUND: Asthma is an inflammatory airway disease caused by interaction between susceptibility genes and diverse environmental factors. In Israel, asthma seems to be familial and more severe in patients of Iraqi Jewish descent. On the other hand, asthma is less frequent in individuals with familial Mediterranean fever, an autoinflammatory disease prevalent in the Iraqi Jewish community and linked to mutations in the familial Mediterranean fever gene, designated MEFV. OBJECTIVES: To explore a possible role for mutated MEFV in the reduced susceptibility to asthma and to determine its expression in Israeli subjects of Iraqi origins. METHODS: Using a case-control approach, we studied the presence of the 3 most common MEFV mutations (M694V, V726A, and E148Q) in DNA samples from 75 patients with asthma and 45 asymptomatic first-degree relatives, all of Iraqi Jewish origin. The severity of asthma was evaluated using a published severity score. RESULTS: Eleven patients with asthma and 14 of their relatives carried 1 or 2 mutations in the MEFV gene, a carrier rate significantly lower in patients with asthma than in their first-degree relatives and in ethnically matched healthy individuals (P < .03 and P < .003, respectively). Carriers of MEFV mutations had less severe disease, compared with noncarriers (P < .002). CONCLUSION: These findings suggest that MEFV mutations may have a protective effect in the pathogenesis of asthma.  相似文献   
9.
PROBLEM: Previously we reported on the generation of experimental anti-phospholipid syndrome (APS) in mice. These models were employed to evaluate the efficacy of various novel therapeutic modalities including interleukin-3 (IL-3) and low dose aspirin. The efficacy of the latter was found to be interrelated. Low dose aspirin is capable of inhibiting the activity of the enzyme cyclooxygenase which is responsible for the metabolism of arachidonic acid towards the production of prostaglandins. This shifts the metabolism of arachidonic acid to the other pathway and leads to an overproduction of leukotrienes. The leukotrienes act as stimulators of IL-3 production, a positive cytokine in pregnancy which enhances placental and fetal development. In the current study we evaluated the IL-3 levels in pregnant women with APS and expanded our knowledge on the interrelationships between aspirin, arachidonic acid metabolites and IL-3 in the human system. METHODS: IL-3 levels were recorded in the serum of pregnant women with APS and compared to a control pregnant group. In addition peripheral blood mononuclear cells from healthy subjects were incubated with different concentrations of aspirin or with arachidonic acid metabolites (Leukotriene B4, C4 or PGE2), and IL-3 production in the culture fluids was evaluated. RESULTS: Serum level of IL-3 in pregnant patients with primary APS, APS secondary to SLE and SLE was lower in comparison to the control group. The in vitro studies revealed that only low dose aspirin (10 mg/μl) stimulated IL-3 production while higher doses of the drug failed to induce the cytokine generation. Leukotriene B4 and C4 were stimulatory whereas PGE2 acted as inhibitor of IL-3 production. CONCLUSIONS: The serum level of IL-3 is decreased to pregnant women with primary or secondary APS. Low dose aspirin is capable of stimulating EL-3 production in vitro most probably through an elevation of leukotriene production, which may explain its beneficial activity in preventing the manifestations of APS.  相似文献   
10.
International Urology and Nephrology - To quantify the occurrence of stent failure and the dynamic behavior of urine flow in ureter-stent systems, including the relative flow in the ureter and...  相似文献   
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