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11.
Q. Peng J. Moan Jahn M. Nesland Jan F. Evensen M. Kongshaug C. Rimington 《Lasers in medical science》1990,5(4):399-409
Observations on time-dependent localization of tetra(3-hydroxyphenyl)porphin (3-THPP) in human malignant melanoma transplanted to athymic nude mice from 1 to 120 h after intraperitoneal (i.p.) 10 mg kg–1 b.w. administration were made by means of fluorescence microscopy. Fluorescence was found on the membrane of the melanoma cells and in the cytoplasm with a peak fluorescence intensity at 24 h post-injection of 3-THPP. The growth of the tumour cells was obviously inhibited at an early stage after PCT. Morphological changes of the tumour at various intervals after treatment by PCT with 3-THPP were also observed. Diffuse degeneration of the tumour cells with swelling of mitochondria and endoplasmic reticulum, heterochromatin aggregation and margination, etc., and subsequently diffuse necrosis with little or no the background of tumorous vascular response were found at an early stage after PCT. On the other hand, it was also observed that the necrosis of the melanoma areas was caused as a consequence of tumorous vascular injury at a later stage after PCT. Thus, two tumoricidal processes caused by PCT with 3-THPP were seen: a direct phototoxic action on tumour cells at an early stage after PCT and an indirect effect secondary to tumorous vascular injury at a later period after PCT. 相似文献
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应用食管调搏,检测64例旁道参与的房室折返性心速患者Ⅰ、Ⅱ、Ⅴ1和食管导联的室房时距、P'v,Pet时距。发现左侧AP者RP'1较RP'V1短(P<0.01),而右侧AP时较RP'v1长(P<0.01)。 相似文献
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Retrospective review of the preoperative biliary and gastrointestinal evaluation for gastric bypass surgery 总被引:1,自引:0,他引:1
Vincent W. Vanek M.D. C.N.S.P. F.A.C.S. Michele Catania R.N. B.S.N. Kimberly Triveri R.D. L.D. Robert W. Woodruff Jr M.D. 《Surgery for obesity and related diseases》2006,2(1):839-22
BACKGROUND: The purpose of this study was to analyze the frequency and results of preoperative biliary and gastrointestinal (GI) evaluation of patients undergoing Roux-en-Y gastric bypass (RYGB). METHODS: Retrospective review of the preoperative evaluation of 144 consecutive RYGB patients. RESULTS: Cholecystectomy had already been performed in 43 (30%) patients; 22% of those patients with an intact gallbladder had cholelithiasis. Ten patients (7%) had an upper GI x-ray (UGI), and 94 patients (65%) had an esophagogastroduodenoscopy (EGD). Abnormalities were found in 40% of the UGIs and 84% of the EGDs. A total of 96 patients (67%) were tested for Helicobacter pylori; 11% were positive. Twenty-one patients (15%) underwent preoperative colonoscopy; 48% were abnormal, but most of the abnormalities were not clinically significant. Three patients had barium enema x-ray, which was normal in all cases. CONCLUSIONS: The preoperative biliary and GI evaluation of bariatric surgery patients should include a routine ultrasound of the gallbladder. Routine preoperative EGD will detect a significant number of abnormalities that should be treated, but should rarely alter the bariatric surgical procedure or result in denial of bariatric surgery. Many abnormalities will be asymptomatic. Patients should be routinely screened for H. pylori and, if positive, treated before bariatric surgery. Lower GI evaluation should be performed selectively based on the patient's symptoms, physical findings, and guidelines for colorectal cancer and polyp screening. 相似文献
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The subthalamic nucleus (STN) is a major target for treatment of advanced Parkinson's disease patients undergoing deep brain stimulation surgery. Microelectrode recording (MER) is used in many cases to identify the target nucleus. A real-time procedure for identifying the entry and exit points of the STN would improve the outcome of this targeting procedure. We used the normalized root mean square (NRMS) of a short (5 seconds) MER sampled signal and the estimated anatomical distance to target (EDT) as the basis for this procedure. Electrode tip location was defined intraoperatively by an expert neurophysiologist to be before, within, or after the STN. Data from 46 trajectories of 27 patients were used to calculate the Bayesian posterior probability of being in each of these locations, given RMS-EDT pair values. We tested our predictions on each trajectory using a bootstrapping technique, with the rest of the trajectories serving as a training set and found the error in predicting the STN entry to be (mean +/- SD) 0.18 +/- 0.84, and 0.50 +/- 0.59 mm for STN exit point, which yields a 0.30 +/- 0.28 mm deviation from the expert's target center. The simplicity and computational ease of RMS calculation, its spike sorting-independent nature and tolerance to electrode parameters of this Bayesian predictor, can lead directly to the development of a fully automated intraoperative physiological procedure for the refinement of imaging estimates of STN borders. 相似文献
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The correlation between microscopic changes with cellular localization of viral antigens was studied in the ileum of 16 cases
infected with bovine viral diarrhea virus (BVDV). Microscopic lesions in the ileum included multifocal erosive and ulcerative
ileitis, severe congestion and hemorrhage, crypt dilation and mucus engorgement, epithelial debris and leukocytes, lymphoid
depletion of Peyer’s patches, herniation of mucosal epithelium into depleted Peyer’s patches, and fibrinoid vasculitis of
submucosal vessels. BVDV antigen was detected by immunohistochemistry in macrophages, dendritic cells, smooth muscle cells,
endothelial cells, epithelial cells of crypts, and mucosal epithelium, together with other mononuclear cells including lymphocytes,
plasma cells, fibroblasts, and intramural ganglial cells. No consistent correlation between the presence of BVDV antigen and
vascular lesions in the ileum was identified. The intensity and distribution of the immunoperoxidase stain in the ileum was
graded as highly positive (18.7%), moderately positive (56.3%), and mildly positive (25%). In conclusion, the pattern and
density of distribution and localization of BVDV antigen in the ileum was not consistently correlated with the severity of
microscopic lesions. 相似文献
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Claudia Ehringer Mikulaninec 《Patient education and counseling》1987,10(3):253-265
This study sought to contrast mailing a booklet to accomplish preoperative instruction with teaching performed by nurses after hospital admission. Sixty-six patients were studied in a 700-bed medical center and were assigned to three teaching groups and a control group which did not receive teaching. The researcher compared the four groups preoperatively after admission to determine the patients' knowledge and ability to perform surgical exercises, as well as their anxiety levels.
Findings were that patients who received a booklet by mail preadmission learned surgical exercises equally well compared to patients taught postadmission, and mastered significantly more exercise behaviors than those receiving no instruction. No statistical difference in anxiety level was found among groups. One may infer that mailing preadmission material should be considered as an effective teaching mode and alternative to postadmission instruction. 相似文献