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Of 394 carotid endarterectomies performed during a 10-year period, 36 (9%) included Dacron patch graft angioplasties. Patch graft angioplasties were used selectively in patients because they had undergone previous carotid endarterectomy or had small-caliber vessels. There were no postoperative infections, occlusions, emboli, stroke, or pseudoaneurysms. In addition, no clinically detectable recurrent stenoses developed in this high-risk group of patients. Twenty-four of the 27 patients available for follow-up were screened for asymptomatic stenoses with spectral analysis and B-mode imaging; there was no sign of hemodynamically significant recurrent stenosis in this group. These encouraging results support the continued selective use of Dacron patch graft angioplasty in carotid surgery.  相似文献   
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0 引言 腹泻标本中同时检出类志贺邻单胞菌和豚鼠气单胞菌 ,在国内尚未见报道 .现报告如下 .1 临床资料 患者 ,女 ,45岁 .主诉于 12 h前因食不洁冷冻鱼类食品后 ,出现腹痛伴腹泻 ,为黄色稀水便转为血水样便 ,9次 / d,每次量约 2 0 0 m L.伴轻度乏力、恶心、里急后重 .腹痛以上腹部及左下腹部为著 ,呈持续隐痛伴有阵发性加重 .于2 0 0 0 - 0 3- 2 7就诊 .体检 :T37.2℃ ,P78次 / min,R16次 /min,BP13/ 8KPa.实验室检查 :WBC10 .8× 10 9· L- 1 ,N0 .84,L 0 .16 .大便常规 :RBC +++/ HP,WBC 3- 9/ HP,便隐血阳性 .取粪便送检做…  相似文献   
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COVID-19 has been sweeping the globe, hitting the United States particularly hard with a state of emergency declared on March 13, 2020. Transplant hospitals have taken various precautions to protect patients from potential exposure. OPTN donor, candidate, and transplant data were analyzed from January 5, 2020 to September 5, 2020. The number of new waiting list registrations decreased, with the Northeast seeing over a 50% decrease from the week of 3/8 versus the week of 4/5. The national transplant system saw near cessation of living donor transplantation (−90%) from the week of 3/8 to the week of 4/5. Similarly, deceased donor kidney transplant volume dropped from 367 to 202 (−45%), and other organs saw similar decreases: lung (−70%), heart (−43%), and liver (−37%). Deceased donors recovered dropped from 260 to 163 (−45%) from 3/8 compared to 4/5, including a 67% decrease for lungs recovered. The magnitude of this decrease varied by geographic area, with the largest percent change (−67%) in the Northeast. Despite the pandemic, discard rates across organ has remained stable. Although the COVID-19 pandemic continues to evolve, OPTN data show recent evidence of stabilization, an indication that an early recovery of the number of living and deceased donors and transplants has ensued.  相似文献   
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Background Merkel cell carcinoma (MCC) is a rare malignant cutaneous tumour, the incidence of which is increasing. Second malignancies have been reported to occur with high incidence in these patients. Objectives We report the rate and nature of multiple malignancies in patients with MCC treated over a 10 year period in Addenbrooke’s Hospital in Cambridge, United Kingdom, as well as the temporal relationship of these additional malignancies to the diagnosis of MCC. Results The 27 patients had an approximately equal sex incidence with a median age at diagnosis of 79 years. Seventy percent (n=19) of patients had a second primary malignant tumour; and 7 of these patients had two or more tumours in addition to the MCC. Eighteen patients had additional cutaneous malignancies: melanoma, squamous cell carcinoma and basal cell carcinoma, and 8 patients presented non‐cutaneous malignancy including colorectal, haematological and breast tumours. Of the 28 additional tumours in our patients, half were diagnosed prior to presentation of MCC, 32% within 6 months of diagnosis, and 18% between 6 months and 3 years after diagnosis. Possible reasons for the high rate of additional tumours in this population are discussed. Conclusions Our figures reflect a higher incidence of multiple malignancies in those with Merkel cell tumour than has previously been reported. This has important implications for the care and surveillance of these patients.  相似文献   
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The bacterial diversity of a subsurface water sample collected from a gas storage aquifer in an Upper Jurassic calcareous formation was investigated by culture of microorganisms and construction of a 16S rRNA gene library. Both culture and molecular techniques showed that members of the phyla Firmicutes and class δ-proteobacteria dominated the bacterial community. The presence of hydrogen-utilizing autotrophic bacteria including sulfate reducers (e.g. Desulfovibrio aespoeensis) and homoacetogens (e.g. Acetobacterium carbinolicum) suggested that CO2 and H2 are the main carbon and energy sources sustaining a nutrient-limited subsurface lithoautotrophic microbial ecosystem (SLiME). Gram-positive SRB belonging to the genus Desulfotomaculum, frequently observed in subsurface environments, represented 25% of the clone library and 4 distinct phylotypes. No Archaea were detected by both experimental approaches.Water samples were collected in an area of the rauracian geological formation located outside the maximum seasonal extension of underground gas storage. Considering the observed microbial diversity, there is no evidence of any influence on the microbial ecology of the aquifer in the surroundings of maximum extension reached by the gas bubble of the underground storage, which should have resulted from the introduction of exogenous carbon and energy sources in a nutrient-limited ecosystem.  相似文献   
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The c-abl proto-oncogene encodes a nonreceptor tyrosine kinase involved in many cellular processes, including signaling from growth factor and antigen receptors, remodeling the cytoskeleton, and responding to DNA damage and oxidative stress. Many downstream pathways are affected by c-Abl. Elevated c-Abl kinase activity can inhibit NF-κB activity by stabilizing the inhibitory protein IκBα, raising the possibility that c-Abl-deficient cells might have increased NF-κB activity. We examined the levels of NF-κB activity in primary mouse embryonic fibroblasts (MEFs) derived from wild-type and c-Abl knockout mice and found that the knockout MEFs indeed exhibited elevated NF-κB activity in response to stimulation as well as constitutively elevated NF-κB activity. Thus, endogenous c-Abl is a negative regulator of basal and inducible NF-κB activity. Examination of various points of NF-κB regulation revealed that unstimulated c-Abl knockout MEFs do not exhibit an increase in IκBα degradation, p65/RelA nuclear translocation, or DNA binding of NF-κB subunits. They do, however, show reduced levels of the histone deacetylase HDAC1, a negative regulator of basal NF-κB activity. Unstimulated c-Abl knockout MEFs are less responsive to induction of NF-κB activity by trichostatin A, an HDAC inhibitor, suggesting that c-Abl might play a role in the HDAC-mediated repression of basal NF-κB activity.  相似文献   
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