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21.
L-acetylcarnitine is a compound with cholinergic properties and putative action on the visual system and the glucose metabolism. Ten healthy, emmertropic volunteers (age range: 21 to 28 years) were studied. Each subject was administered 5, 10, and 30 mg/kg acute intravenous doses of L-acetylcarnitine and matching placebo. Retinal oscillatory potentials to full-field flash stimulation were recorded before and 30, 60, and 120 min after administration. A systematic reduction of the implicit time of the P2 and N2 oscillatory potential components was observed after administration of the 10 and 30 mg/kg doses: significant changes were not evident at the 5 mg dose or after placebo. The latency reduction was significantly correlated with the postdrug increment of the L-acetylcarnitine plasma concentration. No other systematic modification in latency of amplitude was observed.The results were presented in part at the XXV I.S.C.E.V. Symposium, Sarasota (Florida), April 26–30, 1987.  相似文献   
22.
Background: Half of the patients who undergo surgery for cancer of the esophagus or gastric cardia present with recurrent disease within 2 years after the operation. We investigated the value of endosonography for the early detection of recurrent disease. Methods: Forty-three patients entered a follow-up protocol in which endosonography was performed every 6 months within the first 2 years after resection. Results: During 16 of a total of 66 examinations, suspicious abnormalities were found. In three patients free fluid was seen, but recurrence could not be confirmed during follow-up. In eight patients suspicious lymph nodes were seen; six died within 6 months, one was alive with a proven recurrence at 6 months, and one was alive without recurrence at 22 months. In five patients focal wall-thickening or a mass was seen; three died within 6 months, and two were alive with a proven recurrence at 2 and 5 months. After exclusion of free fluid, the positive predictive value of abnormalities on endoscopic ultrasonography (EUS) was 92%. Conclusions: Endosonography, performed at 6-month intervals after resection of cancer of the esophagus or gastric cardia, is accurate in the early detection of locoregional recurrent disease. Two thirds of the patients were still without symptoms when the recurrence was found. (Gastrointest Endosc 1997;46:487-91.)  相似文献   
23.
Preliminary results on the localization of substance P-like immunoreactivity in the human cerebellum are presented. Cerebella from newborn and adult subjects were examined. While only sporadic positive fibres were detected in the adult tissue, the immunoreactive material appeared more abundant in the cerebella from newborn subjects. Varicose and non-varicose fibres and dot-like nerve terminals were present with different density in various regions. The paucity of immunoreactive perikarya suggests that most of the cerebellar substance P-like immunoreactive material has an extrinsic origin.  相似文献   
24.
Urinary excretion of N-acetyl-beta-glucosaminidase (NAG) is an early marker of nephrotoxicity. NAG activity was assayed by the fluorimetric method of Leaback and Walker in 17 patients treated (22 courses) with carboplatin (CBDCA, 220-550 mg/m2) before infusion and 24, 48, 72 and 96 h after. Increased excretion of NAG, a sensitive index of renal tubular damage, was observed following 10 of the 22 courses. A transient increase in plasma creatinine and/or abnormal proteinuria was observed in 6 cases. Impaired renal function prior to therapy seems to be a predisposing factor to the nephrotoxicity.  相似文献   
25.
The length of the thoracic spine was measured in chest roentgenograms of 331 children from birth to 16 years and standards for thoracic spine length in this age group were obtained.  相似文献   
26.
BACKGROUND: We tested the hypothesis that using a subgluteus approach to the sciatic nerve requires a lower concentration of mepivacaine to obtain complete anesthesia as compared with the popliteal approach. METHODS: With midazolam premedication (0.05 mg kg(-1) iv), 48 patients undergoing hallux valgus repair were randomly allocated to receive a sciatic nerve block using either a posterior popliteal (group Popliteal, n = 24) or subgluteus (group Subgluteus, n = 24) approach with 30 mL of local anesthetic injected after elicitation of plantar flexion of the foot with a current 相似文献   
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28.
This study was undertaken to evaluate changes in relative (99m)Tc-hydrazinonicotinamide (HYNIC)-annexin V tumor uptake over time in patients undergoing chemotherapeutic treatment at baseline and at 5-7 h and 40-44 h after treatment initiation. Imaging results are related to clinical outcomes, as assessed with response evaluation criteria in solid tumors (RECIST). METHODS: We prospectively included 20 patients (11 men and 9 women; mean age, 59.8 y; range, 22-75 y) scheduled for chemotherapy (n = 19) or bisphosphonate treatment (n = 1). Curable disease was present in 5 patients. The other patients had metastatic disease and were treated in a palliative setting. Three of the 20 enrolled patients were excluded from analysis: 1 patient ultimately refused the proposed chemotherapy treatment; because of difficulties with the labeling procedure, 1 patient did not receive a pretreatment scan; and 1 patient presented with an allergic reaction (rash and nausea) to the (99m)Tc-HYNIC-annexin V formulation. The remaining 17 patients underwent 3 scintigraphic scans with (99m)Tc-HYNIC-annexin V: before treatment and 5-7 h and 40-44 h after treatment initiation. The tumor response was evaluated with RECIST and related to observed changes in the ratios of tumor activity to background activity for the largest known lesion; values exceeding 25% the baseline value on either the 5- to 7-h scan or the 40- to 44-h scan were considered significant. RESULTS: With the proposed sequential imaging protocol and a 25% change threshold, responders to treatment could be separated from nonresponders with a 94% accuracy (16/17 patients). CONCLUSION: Sequential (99m)Tc-HYNIC-annexin V imaging may allow for assessment of the response to chemotherapy within 3 d after treatment initiation.  相似文献   
29.
OBJECTIVE: It is not well established whether the blood flow of arterial composite Y-grafts can efficiently respond to the flow demand of the coronary system early postoperatively. The aim of this study was to evaluate if soon after the operation, arterial composite Y-grafts can increase blood flow in response to an increase in myocardial oxygen consumption (MVO2). METHODS: Twenty-seven patients who received complete arterial myocardial revascularization using the left internal thoracic artery (LITA) and the radial artery (RA) as composite Y-graft gave their consent to a pre-discharge coronary angiography and intravascular flow velocity measurements using a Doppler guide wire. Flow measurements were performed in the LITA main stem, the distal LITA and the RA, both at rest and during atrial pacing at the 85% of the patient age-predicted maximum. The heart rate-systolic blood pressure product was considered as an indirect index of MVO2. Hyperemic flow was determined after injection of adenosine. The flow reserve (FR) was defined as the ratio of blood flow during maximal hyperemia (Qmax) to baseline flow (Qbasal). RESULTS: Atrial pacing increased MVO2 significantly (P<0.000). None of the patients developed ischemic S-T segment modifications or complained of chest pain. Q(basal) increased significantly in the LITA main stem (P=0.001), distal LITA (P=0.041) and RA (P=0.004) while Qmax did not change significantly. As a consequence, the FR decreased in the LITA main stem (P=0.002), distal LITA (P<0.000) and RA (P<0.000) but was not completely exhausted. CONCLUSIONS: Soon after the operation, arterial composite Y-grafts can significantly increase blood flow in response to conditions of increased MVO2, keeping normal the myocardial O2 supply-to-demand ratio.  相似文献   
30.
Trauma und Berufskrankheit - Zusammenfassung Diese Arbeit beschäftigt sich mit der Häufigkeit, dem Entstehungsmechanismus und der Behandlung von Bizepssehnenrupturen. Veränderte...  相似文献   
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