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21.
Percutaneous transluminal balloon angioplasty (PTA) is being currently used in patients with coronary artery disease. Laser irradiation (LI) has been effective in vaporizing atherosclerotic plaques. The purpose of this work was twofold: to compare PTA and LI techniques in the recanalization of experimental obstructive arterial lesions, and to evaluate the possibility of reducing the failures and local complications and increasing the success rate of PTA by the combined use of LI. Atherosclerotic iliac stenoses were induced in 27 rabbits; lesions were evaluated angiographically before and after intervention and were studied histologically and by electron microscopy. Argon-ion LI delivered through microlens-tip optic fibers reduced the stenotic area from 64.2 +/- 21.8% to 40.3 +/- 10.7% (n = 10, P less than .01) and PTA from 60.7 +/- 15.9% to 30.4 +/- 7.7% (n = 9, P less than .01). However, percentage reduction was higher in PTA-treated stenoses (48.4 +/- 10.1% vs 34.5 +/- 13.5%, P less than .0125). In eight more rabbits, low power LI (4.55 +/- 1.25 J) was delivered after PTA in dilated segments. Post-PTA LI further decreased stenoses (from 31.2 +/- 7.8% to 29.1 +/- 8.1%, P less than .0125); laser-irradiated segments showed diffuse carbonization of the disrupted intimal layer. The normalized transtenotic pressure gradient decreased significantly in all groups: LI reduced the gradient from .40 +/- .25 to .17 +/- .07 (P = .005); PTA from .37 +/- .14 to .11 +/- .04 (P = .001); LI after PTA from .40 +/- .16 to .12 +/- .06 (P = .001). Thus, LI is effective (less than PTA) in relieving experimental atherosclerotic stenoses and seems useful when combined with PTA.  相似文献   
22.
Clinical trials have utilized intermittent diethylstilbestrol diphosphate (DES) therapy in advanced symptomatic prostatic carcinoma to diminish the morbidity of standard endocrine therapy. To determine the effect of intermittent DES administration on the Dunning R3327 rat prostatic adenocarcinoma 60 days following tumor implant, 6 groups were randomly assigned: control (N = 8), castrate (N = 10), high dose DES (N = 8, 1.6 micrograms/ml DES continuously in drinking water), low dose DES (N = 10, 0.4 microgram/ml continuously in drinking water), intermittent high dose DES (N = 10, 1.6 micrograms/ml DES in drinking water for 1 week, then off for 3 weeks), and intermittent low dose DES (N = 10, 0.4 microgram/ml DES for 1 week, then off for 3 weeks). Results indicate that low or high dose DES, and intermittent low or intermittent high dose DES during the week of administration were able to reduce serum testosterone to castrate levels (0.1 ng/ml). After withdrawal of intermittent DES, serum testosterone returned toward control levels (1.0 ng/ml). Initial mean tumor burden between control and treatment groups was not significantly different. All DES exposed rats had a tumor volume at death (range, 15.6-18.3 cm3) smaller than control (mean, 25.4 cm3) or castrate (mean, 40.8 cm3) rats. Despite this significant survival advantage from the time of randomization was achieved only in castrate (median survival, 331 days) or high dose DES (median survival, 359 days) groups compared to control (median survival, 225 days). Similarly, significant prolongation in tumor doubling time was achieved only by rats receiving castration or high dose DES. Intermittent DES administration controls tumor volume but does not provide a survival advantage. In this respect, intermittent DES is inferior to castration.  相似文献   
23.
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   
24.
Currently, the best treatment option for idiopathic cervical dystonia (ICD) is injection of botulinum toxin (BTX) into the affected muscles, whereas rehabilitative approaches have given disappointing results. We evaluated whether the association of an ad hoc rehabilitative program may improve the clinical efficacy of BTX treatment in a single-center, cross-over, controlled study. Forty patients with ICD were randomly assigned to two different treatment groups: (1) BTX type A (BTX-A) plus a specific program of physical therapy (BTX-PT) or (2) BTX-A alone (BTX-0). Patients in the BTX-PT group showed a longer duration of the clinical benefit (118.8 vs. 99.1 days) and needed a lower dose of BTX at reinjection (284.5 vs. 325.5 units). In addition, they showed more marked reductions in their disability in activities of daily living (-9.7 vs. -4.85 points) and subjective pain (-13.35 vs. 6.95 points) scores. Association of BTX-A therapy with a specific program of physical therapy may improve ICD treatment outcome.  相似文献   
25.
Background: Thirty-three patients were candidates for laparoscopic choledochotomy. The indications for this operation are described. Methods: The procedure was completed 32 times (97%). We had 29 successful common bile duct (CBD) clearances, three negative explorations, and one failed clearance which needed to be converted to laparotomy. All the completed procedures ended with primary closure of the main duct. Median duration of surgery was 180 min (range 100–300), including three associated laparoscopic procedures. Results: There were three postoperative complications (9.4%), none major. Average postoperative hospital stay was 7.1 days (range 4–14). In May–June 1995 we controlled 31 out of the 32 consecutive patients (one patient was lost to follow-up) who had a successful laparoscopic choledochotomy from October 1991 to December 1994. Median follow-up was 22 months (range 5–44). Besides clinical control, 23 patients also had ultrasound (US) controls and 24 had blood tests. Eleven had intravenous cholangiotomography. Two patients died 11 and 22 months after the operation for unrelated causes and without biliary symptoms. Two patients had umbilical hernias. One had a small residual asymptomatic stone, which was removed endoscopically. None had signs of postoperative CBD stricture. At US, CBD was ≤7 mm in 15 patients, 8–10 mm in four patients, and 10–12 mm in three patients. The last group had preoperative CBD dilation, too. We could compare preoperative and postoperative CBD diameters in 22 patients: 11 had no change; in nine it decreased; and two had a slight increase (8–10 mm). Conclusions: We conclude that laparoscopic choledochotomy with primary closure is a very good operation: It has a high success rate and low morbidity. Mortality is nil so far. Medium-term results are very positive: We had no CBD stricture and only one case of asymptomatic residual stone, which could have been avoided. Our results suggest that intraductal biliary drainage is useless, and its specific complications are well known. Received: 20 October 1995/Accepted: 28 February 1996  相似文献   
26.
27.
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA.  相似文献   
28.
This article is a retrospective study comparing the efficacy of Regnauld arthroplasty to first ray osteotomies for the treatment of hallux valgus. One hundred consecutive cases of Regnauld arthroplasties were compared with 100 consecutive first ray osteotomies. One hundred fourty-one patients were available for follow-up, and based on clinical/radiographic examinations, 72 were treated with the osteotomy protocol (group A) and 69 with Regnauld arthroplasty (group B). Age at surgery, clinical symptoms, and preoperative radiologic findings were similar for the 2 groups; there was a preponderance of female patients (90%). The average follow-up was 49 months in group A and 51 months in group B. Clinical evaluation showed in the osteotomy group a more stable correction (79% v 49%), greater pain reduction (measured in a visual analog scale from 0 = pain free to 10 = deep intolerable pain), increased residual articular excursion of the first metatarsophalangeal joint (27 degrees of active dorsiflexion from neutral position v 8 degrees ), and less presence of central metatarsalgia (15% v 34%) (P <.05). The radiographic evaluation expressed more stable correction values in group A for the following parameters: joint preservation, sesamoid position, intermetatarsal angle (7 degrees v 12 degrees ), abduction angle of the hallux (14 degrees v 20 degrees ), and proximal articular set angle (8 degrees v 18 degrees ) (P <.05).  相似文献   
29.
Thirteen amidoderivatives of 3-methyl-3,4-dihydro-6-R-benzo-1,2,4-triazin-3-yl-acetic acids and of 3-methyl-3,4-dihydro-pyrido [3,2-e]/[3,4-e]-1,2,4-triazin- 3-yl-acetic acids were prepared and submitted to a wide pharmacological screening. The dihydrobenzotriazine and dihydropyridotriazine moieties were endowed with a wide pharmacogenic capacity; in fact, several compounds exhibited high antiinflammatory [(I c), (I d), (II d), (V f), (VI f)], diuretic [(I f), (I g), (I h)] and antihypertensive activities [(I d), (III d)], as well as minor effects on the C.N.S.  相似文献   
30.
The content of dolichol, an isoprenoid present in all biological membranes, was determined in isolated sinusoidal liver cells after treatment of rats for 2 and 4 months with a low dosage of the hepatotoxin thioacetamide. The significant decrease in dolichol observed in hepatocytes after 2 months might be explained by peroxidation of the isoprenoid. At the same time point, retinol was retained, and decreased only after 4 months of treatment. After 4 months of treatment therefore both lipids decreased. In a subfraction of hepatic stellate cells, Ito-1 cells, the main storage site of vitamin A, dolichol decreased significantly only after 4 months. A remarkable difference from hepatocytes is that in Ito-1 cells retinol content significantly decreased after 2 months of treatment. In another subfraction, Ito-2 cells, the content of the two isoprenoids decreased in parallel. This heterogeneous subfraction might represent those transitional hepatic stellate cells that, while losing retinol, are in the process of differentiating into myofibroblasts secreting extracellular matrix components. In Kupffer cells and sinusoidal endothelial cells, impairment of dolichol might be observed later, only after 4 months of treatment, while retinol decreases uniformly over time. Starting after two months of treatment, the decrease of dolichol and the increase of retinol in hepatocytes, at the same time as retinol decreases in hepatic stellate cells, might be taken as an early index of incipient liver injury due to thioacetamide. This hypothesis is discussed with regard to a role of dolichol in the modulation of membrane fluidity for intracellular and intercellular retinol transport.  相似文献   
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