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991.
Stellate ganglion (SG) neurons provide the main sympathetic innervation to the heart and help to regulate cardiac function. The purpose of this study was to determine if ultrasound imaging could be employed to retrograde label rat SG neurons innervating the heart without employing thoracotomy. In addition, electrophysiological experiments were performed to characterize the modulation of Ca(2+) channels by neurotransmitters in unlabeled and dye-labeled SG neurons. Fluorescence imaging of actutely isolated cells revealed that dye uptake was successful within five days following injection of dye in the cardiac muscle. Whole-cell voltage-clamp recordings revealed that the majority of the Ca(2+) current was carried by N-type Ca(2+) channels. Finally, fluorescence dye uptake did not appear to affect the modulation of Ca(2+) currents following exposure of SG neurons to norepinephrine, adenosine and neurokinin A. These results demonstrate that ultrasound imaging-guided percutaneous injection can be effectively employed to retrograde label neurons innervating the heart. 相似文献
992.
Selective serotonin reuptake inhibitors (SSRIs) are well-established medications for the treatment of mood disorders including major depression. These agents are also known to exhibit potent antiplatelet and endothelium protective effects effects. Additionally, SSRIs can exacerbate the development of inflammation, and modulate the interleukin and interferon production. All of the above suggest that SSRIs therapy could be considered as a potential strategy for the wound healing treatment. We summarized some body of the available data on the history of serotonin metabolism, mechanism of action of ketanserin, and hypothesize why SSRIs may be beneficial in the wound repair natural history. Different pathophysiological considerations are also reflected in this review. Finally, we suggest that the topical use of SSRIs may represent a promising avenue for future strategies affecting wound repair in high-risk patients, especially those with diabetes mellitus, venous insufficiency, obesity, and other vascular disorders. 相似文献
993.
Sofowora GG Dishy V Landau R Xie HG Prasad HC Byrne DW Smiley RM Kim RB Wood AJ Stein CM 《Clinical pharmacology and therapeutics》2004,75(6):539-545
OBJECTIVE: The alpha(1A)-adrenergic receptor is highly expressed in human vasculature including resistance arteries and veins, and its stimulation is primarily responsible for adrenergically mediated smooth muscle contraction. Variability in sensitivity to phenylephrine, an alpha(1A) adrenergic agonist, has a large genetic component. We examined the hypothesis that a common polymorphism of alpha(1A)-adrenergic receptor (Arg347Cys) affects in vivo response. METHODS: We measured vascular sensitivity to phenylephrine using the dorsal hand vein linear variable differential transformer technique and determined alpha(1A)-adrenergic receptor genotype in 74 healthy, nonsmoking adults (28 Arg/Arg, 30 Arg/Cys, and 16 Cys/Cys). RESULTS: Sensitivity to phenylephrine, expressed as the dose of phenylephrine resulting in 50% venoconstriction (Phe(50)), was not significantly different in subjects with the 3 alpha(1A) adrenergic receptor genotypes: Phe(50) geometric mean (95% confidence interval) was 513 ng/min (287-918 ng/min) for Arg/Arg, 431 ng/min (274-680 ng/min) for Arg/Cys, and 471 ng/min (197-1124 ng/min) for Cys/Cys (P =.90). CONCLUSION: We conclude that the Arg347Cys receptor polymorphism does not alter agonist-mediated venoconstriction in vivo. 相似文献
994.
In vitro activity of anidulafungin against selected clinically important mold isolates 总被引:7,自引:0,他引:7 下载免费PDF全文
Odabasi Z Paetznick VL Rodriguez JR Chen E Ostrosky-Zeichner L 《Antimicrobial agents and chemotherapy》2004,48(5):1912-1915
In this study, we evaluated the in vitro activity of anidulafungin against selected mold isolates. Anidulafungin showed promising activity against Bipolaris spicifera, Exophiala jeanselmei, Fonsecaea pedrosoi, Madurella mycetomatis, Penicillium marneffei, Phialophora verrucosa, Pseudallescheria boydii, Sporothrix schenckii, and Wangiella dermatitidis. 相似文献
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Re-operation for hyperparathyroidism 总被引:1,自引:0,他引:1
INTRODUCTION: Re-operation for hyperparathyroidism (HPT) represents a challenge for experienced endocrine surgeons. The present study reviews the technical and pathological factors for failure of initial surgery and identifies strategies to approach re-operative parathyroidectomy. METHODS: Clinical details, operation notes, pathology, localization studies and complications for re-operative cases performed by three surgeons were reviewed. RESULTS: Over a 10-year period there were 40 re-operative cases with a 98% success rate. There were 31 patients with primary HPT, 21 with persistent primary (PP) and 10 with recurrent primary (RP). Multigland disease (MGD) was present in 19 of the 31 (61%) primary HPT cases. The culprit gland was ectopic in 14 cases, at a normal location in 10 and there was regrowth at previously excised sites or remnant disease in 10. There were nine patients with secondary HPT, four with persistent secondary (PS) and five with recurrent secondary (RS). The culprit gland was ectopic in five, at a normal location in four and regrowth at a previously excised site in two. Pre-operative investigations were employed in all cases and the most helpful were sestamibi scan (S) and selective venous sampling (SVS) for parathyroid hormone (PTH) concentration. True positive localizations for S was in 20 of 34 cases (59%), SVS in seven of nine (78%), computed tomography (CT) in seven of 17 (41%) and ultrasound scan (USS) in 10 of 28 (36%). CONCLUSIONS: Re-operative parathyroidectomy can be performed by experienced surgeons with a very high success rate and minimal complications. 相似文献
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