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991.
992.
Mrs. Duong had coronary artery disease, ischemic cardiomyopathy, and mildly altered mental status when her case was presented before an advanced heart therapy medical review board. She was accepted for left ventricular assist device placement pending additional insight into her cognitive state. Before the LVAD could be implanted, however, Mrs. Duong went into cardiogenic shock, and her heart failure team placed an intra-aortic balloon pump in her subclavian artery. Within two weeks, Mrs. Duong became IABP dependent and deconditioned. The attending deemed her as lacking capacity to make complex medical decisions, and the medical review board officially declined her for LVAD placement. The heart failure and CICU teams feel that Mrs. Duong is not being helped by the care they are giving her. They recommend terminal weaning of the IABP and initiation of comfort care. Her family disagrees, pointing to activities like continued eating and interacting with family. At an impasse after yet another family meeting, the attending for the heart failure team asks the clinical ethics consultant, “Do we have to replace the balloon pump when it fails?”  相似文献   
993.
BACKGROUND: We report a unique case of an acquired pial arteriovenous fistula occurring after an asymptomatic thrombosis of a superficial cerebral vein. CASE DESCRIPTION: A cerebral angiogram performed in a 51-year-old man with subarachnoid hemorrhage revealed a 10-mm ruptured anterior communicating artery aneurysm and a thrombosed left superficial middle cerebral vein. Coil embolization of the anterior communicating aneurysm was performed. Follow-up angiography 18 months later revealed a new, asymptomatic, pial arteriovenous fistula between the previously thrombosed left superficial middle cerebral vein and a small sylvian branch of the left middle cerebral artery. CONCLUSIONS: This case provides evidence that pial arteriovenous fistulas may develop as acquired lesions and furthermore may rarely follow cerebral vein thrombosis. Several cases of dural arteriovenous fistulas, as well as a single case of a mixed pial-dural arteriovenous fistula, occurring after dural sinus thrombosis have been reported previously. However, to our knowledge, this is the first report of an acquired pial arteriovenous fistula following a cerebral vein thrombosis.  相似文献   
994.
BACKGROUND AND PURPOSE: Vertebrobasilar territory ischemia (VBI) leads to disabling neurological symptoms and poses a risk for stroke by an embolic or flow-related mechanism. We present our clinical experience in the endovascular treatment of patients with symptomatic VBI from severe atherosclerosis or dissection of the vertebral and subclavian arteries that was unresponsive to medical therapy. METHODS: Twenty-one patients (9 female, 12 male) with a mean age of 65.7 years (range 47 to 81 years) underwent treatment with percutaneous endovascular balloon angioplasty and stent placement. Sixteen patients (76.2%) had evidence of contralateral involvement, and 9 (42.8%) demonstrated severe anterior-circulation atherosclerosis. Nine patients had a previous infarct in the occipital lobe, cerebellum, or pons before treatment. Follow-up was available for all patients. RESULTS: Balloon angioplasty with intravascular stent placement was performed in 13 vertebral artery lesions (10 at the origin, 3 in the cervical segment) and in 8 subclavian lesions. The prestenting stenosis was 75% (50% to 100%) and was reduced to 4.5% (0% to 20%) after stenting. Six of the patients with proximal subclavian stenosis demonstrated angiographic evidence of subclavian steal, which resolved in all cases after treatment. All patients showed improvement in symptoms after the procedure except for 1 who developed a hemispheric stroke after thrombotic occlusion of an untreated cavernous carotid artery stenosis (rate of major stroke and mortality=4.8%). One patient (4.8%) had a periprocedural transient ischemic attack (TIA), and none had minor stroke. At long-term follow-up (mean=20.7+/-3.6 months) of the surviving 20 patients, 12 (57.1%) remained symptom-free, 4 (19%) had at most 1 TIA over a 3-month period, 2 (9.5%) had at most 1 TIA per month, and 2 (9.5%) had persistent symptoms. There were no clinically evident infarcts during the follow-up period. CONCLUSIONS: Endovascular treatment using balloon angioplasty with intravascular stent placement for symptomatic stenotic lesions resulting in VBI that is unresponsive to medical therapy appears to be of benefit in this high-risk subset of patients with poor collateral flow.  相似文献   
995.
996.
Context: Tethered cord syndrome is a progressive condition usually diagnosed early in life, and leads to a diversity of manifestations including neurologic, urologic, and orthopedic dysfunction.Findings: We report two cases of tethered cord syndrome associated with a unilaterally absent sural sensory response on nerve conduction studies while other causes of this finding being excluded.Conclusion/clinical relevance: We believe that this finding is caused by a selective injury of sensory fibers at the level or distal to the dorsal root ganglia.  相似文献   
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998.
999.
We present the complete 2,843,201-bp genome sequence of Treponema denticola (ATCC 35405) an oral spirochete associated with periodontal disease. Analysis of the T. denticola genome reveals factors mediating coaggregation, cell signaling, stress protection, and other competitive and cooperative measures, consistent with its pathogenic nature and lifestyle within the mixed-species environment of subgingival dental plaque. Comparisons with previously sequenced spirochete genomes revealed specific factors contributing to differences and similarities in spirochete physiology as well as pathogenic potential. The T. denticola genome is considerably larger in size than the genome of the related syphilis-causing spirochete Treponema pallidum. The differences in gene content appear to be attributable to a combination of three phenomena: genome reduction, lineage-specific expansions, and horizontal gene transfer. Genes lost due to reductive evolution appear to be largely involved in metabolism and transport, whereas some of the genes that have arisen due to lineage-specific expansions are implicated in various pathogenic interactions, and genes acquired via horizontal gene transfer are largely phage-related or of unknown function.  相似文献   
1000.
Low uptake of cascade screening for βeta-thalassaemia major (β-TM) in the ‘Punjab Thalassaemia Prevention Project’ (PTPP) in Pakistan led to the development of a ‘decision support intervention for relatives’ (DeSIRe). This paper presents the experiences of relatives of children with β-TM of the DeSIRe following its use by PTPP field officers (FOs) in routine clinical practice. Fifty-four semi-structured qualitative interviews were conducted (April to June 2021) with relatives in seven cities in the Punjab province (Lahore, Sheikhupura, Nankana Sahab, Kasur, Gujranwala, Multan and Faisalabad). Thematic analysis shows that participants were satisfied with the content of the DeSIRe and its delivery by the FOs in a family meeting. They understood that the main purpose of the DeSIRe was to improve their knowledge of β-TM and its inheritance, and to enable them to make decisions about thalassaemia carrier testing, particularly before marriage. Participants also raised concerns about the stigma of testing positive; however, they believed the DeSIRe was an appropriate intervention, which supported relatives to make informed decisions. Our findings show that the DeSIRe is appropriate for use by healthcare professionals in routine practice in a low-middle income country, and has the potential to facilitate shared decision making about cascade screening for thalassaemia. Further research is needed to prove the efficacy of the DeSIRe.Subject terms: Patient education, Genetic counselling  相似文献   
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