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91.
92.
The ability to ablate atheroma without generating heat makes the excimer laser wavelength a promising intraluminal technique for the treatment of arterial occlusive disease. This series reviews a preliminary experience treating patients with superficial femoral arterial disease admitted with limb-threatening ischemia or claudication. Twenty-six diseased superficial femoral arteries (5 stenotic and 21 occluded) were treated in 23 consecutive patients. Patients with claudication (18) reluctant to undergo bypass or with limb-threatening ischemia (8) at extremely high risk for surgery were included. There were 10 men and 13 women with a mean age of 67 years. A 308 nm excimer laser with an over-the-wire catheter (19) or balloon-centered end-on catheter (7) was used followed by balloon angioplasty. Twenty-four procedures were performed percutaneously, and two were performed with the vessel open in the operating room. Technical success, defined as disobliteration confirmed by angiography and greater than 0.15 increase of the ankle/brachial index, was achieved in 15 of 26. Eleven of 21 occlusions (52%) and four of five stenoses (80%) were opened. Only two of 11 lesions longer than 10 cm were successfully treated. Unsuccessful attempts (technical failure) occurred in 11 of 26 patients and resulted in four elective and one emergency femoral-popliteal bypass. Five patients were discharged with their claudication unchanged, and one had an elective amputation. Six arterial perforations with three arteriovenous fistulas occurred, all resolved without operation. No unanticipated limb loss occurred. In the 15 successful cases, the mean ankle/brachial index increase was 0.34. Seven (47%) of these 15 remain patent with a mean follow-up of 9.5 months (1.5 to 14 months).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
93.
Twenty-five patients with invasive transitional cell carcinoma of the bladder (Stage T2, T3, T4) received combined modality therapy using four cycles of methotrexate, vinblastine, adriamycin, and cisplatin (MVAC) chemotherapy followed by surgery or radiation therapy (RT). Sixteen patients had complete (N = 8) or partial (N = 8) response to MVAC. Curative RT was delivered to 11 responders with T2 or T3 disease and to 2 patients with T4 disease. All 11 with T2 and T3 disease are currently alive, 7 with normal bladder function. The two with T4 disease are dead of disease. Three patients required salvage cystectomy for local recurrence and one patient had cystectomy for bladder stones. Follow-up ranged from 11 to 50 months with a median of 31 months. No late chemo-radiotherapy treatment-related complications to the intestines or in bladder function (other than one bladder stone formation) occurred. These preliminary results are encouraging and warrant further evaluation of this innovative approach in treating invasive carcinoma of the bladder. T2 and T3 patients with a complete or partial response to MVAC may be excellent candidates for a bladder-sparing treatment.  相似文献   
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95.
PURPOSE: A multicenter phase II trial of ranpirnase (Onconase; Alfacell Corp, Bloomfield, NJ) as a single agent was conducted to further assess the safety and clinical efficacy of this novel antitumor ribonuclease. Patients with unresectable and histologically confirmed malignant mesothelioma (MM) were eligible. PATIENTS AND METHODS: One hundred five patients with Eastern Cooperative Oncology Group performance status 0 to 2 were enrolled onto the study. Thirty-seven percent of patients had not responded to prior chemotherapy. The primary end point of the study was survival. Tumor responses and time to progression were also assessed. The Cancer and Leukemia Group B (CALGB) prognostic group criteria were used to define a treatment target group (TTG). Both the intent-to-treat (ITT) and the TTG populations were analyzed for survival. RESULTS: Median survival times of 6 months for the ITT and 8.3 months for the TTG populations were observed. The 1- and 2-year survival rates were 34.3% and 21.6% for ITT, respectively, and 42% and 26.8% for TTG, respectively. Among the 81 patients assessable for tumor response, four had partial responses, two had minor regressions, and thirty-five experienced stabilization of previously progressive disease. Patients with responses and stable disease demonstrated markedly prolonged survival. Ranpirnase was well tolerated in the majority of patients, and there were no drug-related deaths. CONCLUSION: Ranpirnase demonstrated activity and a tolerable toxicity profile in patients with unresectable MM. The prognostic value of the CALGB groups was confirmed.  相似文献   
96.
97.
中药贝母类的研究——ⅩⅦ.贝母鳞叶上表皮显微观察   总被引:4,自引:0,他引:4  
本文对浙贝母Fritillaria thunbergii Miq.等20种贝母的鳞叶上(内)表皮进行了显微观察,发现种间在表皮细胞形状、大小和垂周壁部位角质栓(cuticular peg)的形状,大小和排列等方面有一定区别,可作为新的鉴别依据。全文除描述外,列出检索表,并附主要特征图。  相似文献   
98.
Each case of conjoint twins is unique. Preoperative imaging is helpful to determine the feasibility of separation. Shared and separate organs can be delineated; and operative technique and problems anticipated. We performed ultrasonography, CT, magnetic resonance imaging, and arteriography preoperatively on ischiopagus conjoint twins. The single most helpful study was CT performed during a bolus intravenous contrast medium injection into one twin. Arteriography was also very helpful. The other studies were complementary but added little additional structural details. Sedation of conjoint twins is complicated yet crucial for optimal imaging studies. A combination of oral and intramuscular sedation was used and worked well for all of the studies.  相似文献   
99.
Intravenous digital subtraction renal angiography (DSRA) has been compared with conventional angiography only in small, selected series of hypertensive patients. The authors prospectively examined with intravenous DSRA 94 patients at increased risk for renovascular hypertension and compared these studies with conventional angiography. A stenosis of at least one main renal artery was identified with intravenous DSRA in 22 patients and confirmed in 20 patients. No significant stenoses were seen with conventional angiography in any of the 64 patients in whom lesions were not seen with intravenous DSRA. Since inadequate DSRA studies were considered positive for renal artery stenosis, the sensitivity of intravenous DSRA was 100% (25 of 25); specificity, 93% (64 of 69); positive predictive value, 83% (25 of 30); and negative predictive value, 100% (64 of 64). The authors conclude that intravenous DSRA is a sensitive test for identifying stenosis of the main renal arteries and is appropriate to use as a screening test among patients at increased risk for renovascular hypertension.  相似文献   
100.
Mechanical loading of bone is important for maintenance of bone mass and structural stability of the skeleton. When bone is mechanically loaded, movement of fluid within the spaces surrounding bone cells generates fluid shear stress (FSS) that stimulates osteoblasts, resulting in enhanced anabolic activity. The mechanisms by which osteoblasts convert the external stimulation of FSS into biochemical changes, a process known as mechanotransduction, remain poorly understood. Focal adhesions are prime candidates for transducing external stimuli. Focal adhesion kinase (FAK), a nonreceptor tyrosine kinase found in focal adhesions, may play a key role in mechanotransduction, although its function has not been directly examined in osteoblasts. We examined the role of FAK in osteoblast mechanotransduction using short interfering RNA (siRNA), overexpression of a dominant negative FAK, and FAK?/? osteoblasts to disrupt FAK function in calvarial osteoblasts. Osteoblasts were subjected to varying periods oscillatory fluid flow (OFF) from 5 min to 4 h, and several physiologically important readouts of mechanotransduction were analyzed including: extracellular signal‐related kinase 1/2 phosphorylation, upregulation of c‐fos, cyclooxygenase‐2, and osteopontin, and release of prostaglandin E2. Osteoblasts with disrupted FAK signaling exhibited severely impaired mechanical responses in all endpoints examined. These data indicate the importance of FAK for both short and long periods of FSS‐induced mechanotransduction in osteoblasts.  相似文献   
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