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The aim of the present study was to examine the effects of cold storage on the responses induced by electrical field stimulation (EFS) in human bronchial preparations. Responses induced by EFS and acetylcholine were studied in human bronchial rings mounted in organ baths, either on the day of surgery or after storage at 4 degrees C in Krebs-Henseleit solution for 24 and 48 h, respectively. The responses induced by EFS were studied at different voltages (20, 40 and 60 V) and at a range of frequencies (2, 4, 8, 10, 30 and 60 Hz). EFS induced a triphasic response, consisting of a cholinergic contraction, followed by a relaxation and subsequently a slow sustained contraction. The amplitude of the EFS-induced response was enhanced with increasing voltages and increasing frequencies. None of the three EFS-induced phases were significantly altered by cold storage at 24h, whereas storage for 48 h significantly decreased the reactivity of the preparations. Likewise, the contractions induced by acetylcholine were unaltered after 24h, but significantly depressed after 48 h. These results suggest that the reactivity of human bronchial preparations to EFS is not altered when tissues are conserved for 24h, whereas prolonged storage should be avoided.  相似文献   
994.
The aim of this study is to generate normal reference values of cerebral blood flow velocities (CBFV) and Doppler indices (DI) in the anterior (ACA) and the middle (MCA) cerebral arteries during the first month of life in "healthy" preterm infants. CBFV were obtained with color Doppler technique in seventy selected preterm infants divided in four groups of gestational age (GA) (25 to 28; 29 to 30; 31 to 32; 33 to 35 wk). Our data demonstrate that CBFV increase with rising GA, birth weight (BW) and postnatal age. Additionally, we can provide the median values, tenth and ninetieth percentiles of CBFV and DI, in the ACA and MCA in each GA group as reference normal values of CBFV and DI in preterm newborn.  相似文献   
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An inadvertent case of pericardial placement of a central venous catheter was successfully treated by direct thrombin injection.  相似文献   
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Background We sought to identify the risk of axillary node involvement in patients with ductal carcinoma in situ (DCIS) and to determine whether axillary node assessment is necessary in these patients. Sentinel node biopsy (SNB) is replacing standard axillary lymph node dissection (ALND) for surgical staging of invasive breast cancer. Its use in patients with DCIS versus local excision (LE), observation, and/or breast irradiation remains in question. Methods We examined the records of 813 patients with localized DCIS and disease-negative margins after LE who were randomly assigned to no further therapy or to breast irradiation in National Surgical Adjuvant Breast and Bowel Project (NSABP) trial B-17 and 1799 patients randomized to receive placebo or tamoxifen after LE + radiotherapy in NSABP trial B-24. An ALND was performed in 253 patients in NSABP B-17 and in 162 in NSABP B-24. Results We found that in NSABP trial B-17, seven patients developed ipsilateral nodal recurrence (INR). Overall INR rate was 0.83/1000 patient-years. In NSABP B-24, overall INR rate was 0.36/1000 patient-years. INR can be considered a surrogate for axillary involvement at the time of DCIS diagnosis. Conclusions INR in patients with DCIS treated conservatively is extremely rare. Our findings do not support the routine use of SNB in patients with conservatively treated, localized DCIS. Presented in part at the Society of Surgical Oncology meeting, March 2006.  相似文献   
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