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1.
《Anaesthesia and Intensive Care Medicine》2020,21(11):572-577
Phaeochromocytomas and paragangliomas (PPGL) are catecholamine-secreting neuroendocrine tumours. These tumours may be identified incidentally, as part of a work-up for multiple endocrine neoplasia or following haemodynamic surges during unrelated procedures. Advances in preoperative management and improved management of intraoperative haemodynamic instability have significantly reduced surgical mortality from around 40% to less than 3%. Surgery is the definitive treatment in most cases and laparoscopic resection where possible is associated with improved outcomes. Anaesthetic management of PPGL cases represents a unique haemodynamic challenge both before, during and after tumour resection. In this article we describe the physiology of these tumours, their diagnosis, preoperative optimization methods, intraoperative anaesthetic management and management of postoperative complications. 相似文献
2.
《Clinical neurophysiology》2021,132(12):3104-3115
ObjectiveWe aimed to establish an objective neurophysiological test protocol that can be used to assess the somatosensory nervous system.MethodsIn order to assess most fiber subtypes of the somatosensory nervous system, repetitive stimuli of seven different modalities (touch, vibration, pinprick, cold, contact heat, laser, and warmth) were synchronized with the electroencephalogram (EEG) and applied on the cheek and dorsum of the hand and dorsum of the foot in 21 healthy subjects and three polyneuropathy (PNP) patients. Latencies and amplitudes of the modalities were assessed and compared. Patients received quantitative sensory testing (QST) as reference.ResultsWe found reproducible evoked potentials recordings for touch, vibration, pinprick, contact-heat, and laser stimuli. The recording of warm-evoked potentials was challenging in young healthy subjects and not applicable in patients. Latencies were shortest within Aβ-fiber-mediated signals and longest within C-fibers. The test protocol detected function loss within the Aβ-fiber and Aδ-fiber-range in PNP patients. This function loss corresponded with QST findings.ConclusionIn this pilot study, we developed a neurophysiological test protocol that can specifically assess most of the somatosensory modalities. Despite technical challenges, initial patient data appear promising regarding a possible future clinical application.SignificanceEstablished and custom-made stimulators were combined to assess different fiber subtypes of the somatosensory nervous system using modality-specific evoked potentials. 相似文献
3.
Aging alters bladder functions where a decrease in filling, storage and emptying is observed. These changes cause urinary incontinence, especially in women. The aim of this study is to examine how aging affects the intracellular calcium movements due to agonist-induced contractions in permeabilized female rat bladder. Urinary bladder isolated from young and old female Sprague-Dawley rats were used. Small detrusor strips were permeabilized with β-escin. The contractile responses induced with agonists were compared between young and old groups. Carbachol-induced contractions were decreased in permeabilized detrusor from old rats compared to young group. Heparin and ryanodine decreased carbachol-induced contractions in young rats where only heparin inhibited these contractions in olds. Caffeine-induced contractions but not inositol triphosphate (IP3)-induced contractions were decreased in old group compared to youngs. The cumulative calcium response curves (pCa 8–4) were also decreased in old rats. Carbachol-induced calcium sensitization responses did not alter by age where GTP-β-S and GF-109203X but not Y-27632 inhibited these responses. Carbachol-induced contractions decrease with aging in rat bladder detrusor. It can be postulated as IP3-induced calcium release (IICR) is primarily responsible for the contractions in older rats where the decrease in carbachol contractions in aging may be as a result of a decrease in calcium-induced calcium release (CICR), rather than carbachol-induced calcium sensitization. 相似文献
4.
目的:探讨改良大骨瓣联合软通道微创介入逐渐减压术治疗重型颅脑损伤的疗效。方法方便选择自2009年12月—2014年11月该院收治的重型颅脑损伤病例70例,随机分为改良组和对照组2组,每组35例,改良组施行改良大骨瓣联合软通道微创介入逐渐减压术,对照组按标准大骨瓣开颅、硬脑膜一次性全切开,对比分析两组的并发症发生率及预后。结果改良组发生迟发性颅内血肿、大面积脑梗塞及弥漫性脑肿胀等并发症9例(25.7%,9/35),预后良好者23例(65.7%,23/35),对照组发生并发症19例(54.3%,19/35),预后良好者14例(40.0%,14/35),两组并发症发生率和预后差异具有统计学意义(P<0.05)。结论改良大骨瓣联合软通道微创介入逐渐减压术治疗重型颅脑损伤,效果良好,显著降低死亡率。 相似文献
5.
Ramya Deepthi Vinnakota Allan S. Brett 《The American journal of the medical sciences》2019,357(2):160-163
Iron deficiency anemia is often listed among potential adverse effects of gastric acid-suppressive medications, given that gastric acidity promotes intestinal absorption of nonheme iron. Additionally, the antacid calcium carbonate can inhibit iron absorption. However, there is little direct clinical evidence that proton-pump inhibitors, histamine-2 receptor antagonists, or calcium carbonate cause iron deficiency anemia. Most case reports have had substantial limitations (e.g., minimal follow-up and presence of other causes of iron deficiency), and retrospective cohort studies have lacked sufficient patient-specific detail to make strong causal inferences. We present 2 cases—both with detailed, prospective 10-year follow-up—in which combinations of proton-pump inhibitors, histamine-2 receptor antagonists and calcium carbonate were clearly associated with development of iron deficiency anemia. Overt iron-deficiency anemia is probably uncommon in patients who use acid-modifying medications and who have no other conditions that predispose to iron deficiency. Nevertheless, clinicians should be aware of this potential complication, given widespread use of these agents. 相似文献
6.
Michael M Gezalian Luigi Mangiacotti Padmesh Rajput Nicklaus Sparrow Konrad Schlick Shouri Lahiri 《Journal of cerebral blood flow and metabolism》2021,41(4):693
Adrenoceptor and calcium channel modulating medications are widely used in clinical practice for acute neurological and systemic conditions. It is generally assumed that the cerebrovascular effects of these drugs mirror that of their systemic effects – and this is reflected in how these medications are currently used in clinical practice. However, recent research suggests that there are distinct cerebrovascular-specific effects of these medications that are related to the unique characteristics of the cerebrovascular anatomy including the regional heterogeneity in density and distribution of adrenoceptor subtypes and calcium channels along the cerebrovasculature. In this review, we critically evaluate existing basic science and clinical research to discuss known and putative interactions between adrenoceptor and calcium channel modulating pharmacotherapies, the neurovascular unit, and cerebrovascular anatomy. In doing so, we provide a rationale for selecting vasoactive medications based on lesion location and lay a foundation for future investigations that will define neuroprotective paradigms of adrenoceptor and calcium channel modulating therapies to improve neurological outcomes in acute neurological and systemic disorders. 相似文献
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9.
携载rhBMP-2微球的新型可注射自凝固复合人工骨的制备及特性研究 总被引:7,自引:1,他引:6
[目的]制备一种具有良好降解性和成骨活性、可注射的自凝固新型骨修复材料。[方法]制备携载rhBMP-2的聚乳酸与聚乙醇酸共聚物(PLGA)微球,并将其与rhBMP-2/磷酸钙骨水泥(CPC)复合,制备出rhBMP-2/PLGA微球/CPC复合人工骨。探讨了材料的特性,包括形貌、固化时间、抗压强度及反映材料体外降解速度的指标一体外降解液Ca、P浓度变化,测定复合材料rhBMP乏的释药速度及体外诱导MSCs细胞成骨分化的能力。[结果]与单纯CPC-rhBMP-2相比,复合材料的固化时间少量增加,抗压强度下降明显。体外降解速度及体外释药明显提高,释放的rhBMP-2具有骨诱导活性。[结论]rhBMP-2/PLGA微球/磷酸钙骨水泥新型复合人工骨是具有良好应用前景的骨修复材料。 相似文献
10.
Bi-Hua BIE Yong CHEN Zhi-Qi ZHAO Institute of Neurobiology Fu-Dan University Shanghai China Institute of Shanghai Physiology Chinese Academy of Sciences Shanghai China 《中国神经科学杂志》2006,(2)
Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinoci-ceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency ( PWL) to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion (DRG) neurons. Results Intraplantar injection of ligustrazine (0.5 mg in 25μl) significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion (DRG) neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin (TTX) -resistant sodium current in relatively selective and dose-dependent manner with IC50 of 2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron in the rat. 相似文献