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51.
To evaluate the reliability of phosphorus-31 magnetic resonance (MR) spectroscopy in the assessment of acute testicular ischemia, vascular integrity, and spermatogenesis, the authors studied in vivo canine and primate testicles grouped as follows: group 1 testes (n = 8), in situ canine controls; group 2 (n = 11), canine testes subjected to warm ischemia; group 3, canine (n = 4) and primate (n = 4) testicles from hormone-treated animals. Group 1 control testicles showed high monophosphoester (MP) levels; low levels of inorganic phosphate (Pi), phosphodiester (PD), and phosphocreatine; and high levels of adenosine triphosphate (ATP). Group 2 testes revealed a time-dependent decay of MP/Pi ratios (from 2.1 to 0.70). Regeneration of ATP was noted in the acute reperfusion period. After 6 weeks of pituitary gonadotropin suppression, group 3 testes showed a significant decrease (P less than .05) in MP/PD ratios from a control level of 2.6 +/- 0.3 and a decrease in the MP/beta-ATP ratio from 2.4 +/- 0.1 to 1.8 +/- 0.3. P-31 MR spectroscopy appears to be a potential method for noninvasively assessing testicular ischemic injury and the metabolic integrity of spermatogenesis.  相似文献   
52.
Meniscal tears of the knee: accuracy of MR imaging   总被引:39,自引:0,他引:39  
Crues  JV  d; Mink  J; Levy  TL; Lotysch  M; Stoller  DW 《Radiology》1987,164(2):445-448
Before surgery, 277 menisci in 144 knees were examined with magnetic resonance (MR) imaging. They were then examined directly with arthroscopy or arthrotomy. Menisci were graded on a scale of 1-3 according to the character of the intrameniscal MR imaging signal. At surgery, 137 of 154 (89%) menisci exhibiting only grade 1 or grade 2 signal were found to be normal. One hundred sixteen of 123 (94%) menisci exhibiting intrameniscal signal communicating with a meniscal articular surface (grade 3 signal) had tears. If only a grade 3 signal is considered consistent with meniscal tears, then MR findings and surgical findings agreed in 91.3% of menisci. MR imaging can separate surgically significant from nonsignificant meniscal lesions and is useful in the noninvasive preoperative screening of suspected meniscal tears.  相似文献   
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Primary biliary carcinoma: CT evaluation   总被引:19,自引:0,他引:19  
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咪苯嗪酮(CI-914)能抑制大鼠血小板环氧酶和TXA2合成酶产物HHT的生成,而对脂氧酶产物12-HETE的生成仅高浓度药物才有弱的抑制作用,提示CI-914主要影响花生四烯酸(AA)环氧酶途径,而对脂氧酶途径影响较少。在大鼠血小板和中性白细胞CI-914能抑制TXA2的生成,同时CI-914还可使白细胞6-keto-PGF1a和血小板PGE2的产生量显著增加,提示CI-914在这两种细胞引起了AA的转向合成。上述结果基本证实,CI-914在大鼠中性白细胞和血小板对TXA2合成酶具有选择性抑制作用。  相似文献   
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To investigate the role of central neurotransmitters in the pathogenesis of migraine, we measured cerebrospinal fluid (CSF) levels of certain amino acids (glycine, taurine, glutamine) and metabolites of biogenic amines (5-hydroxyindoleacetic acid and homovanillic acid) in 38 migraine patients and compared them with the levels from 10 headache-free controls. The levels of taurine, glycine and glutamine were significantly higher in the migraine patients (p < 0.0001 for taurine and glycine; p < 0.0009 for glutamine); there were no significant differences among the three migraine subgroups (infrequent migraine, frequent migraine and transformed migraine). In seven patients subsequently treated with divalproex sodium, CSF taurine levels decreased significantly from pretreatment baseline values. These data support the concept that migraine is at least in part a disorder of central neurotransmission.  相似文献   
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We compared patient morbidity associated with temporomandibular joint (TMJ) arthrography using both meglumine/sodium diatrizoate (60%) and the new monoacidic dimer, Hexabrix, in a double-blind randomized clinical trial in 31 patients. Patients experienced maximal discomfort from TMJ arthrography with the initial joint filling and joint distension; this rapidly resolved over 10 minutes. Delayed exacerbation of pain is less than described for shoulder arthrography. The newer contrast media promise to decrease patient morbidity with arthrography.  相似文献   
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