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61.
SARS病疫的肆虐和对HVAC设计规范的思考 总被引:1,自引:0,他引:1
就新风量的设计标准 ,空气过滤要求与过滤器的设计选用 ,送风量与排风量的平衡 ,军团菌与喷淋式冷却塔 ,及制冷系统与制冷机房的安全设计与安全运行等 5个问题 ,对国家标准《采暖通风与空气调节设计规范》报批稿提出了应急修改建议 ,供有关主管部门研究考虑和同行讨论。 相似文献
62.
Yalavarthy R Edelstein CL Teitelbaum I 《Hemodialysis international. International Symposium on Home Hemodialysis》2007,11(Z3):S7-12
Acute renal failure (ARF) and chronic kidney disease (CKD) are common complications after liver transplantation (LTx). The incidence of ARF post-LTx varies between 48% and 94%; 8% to 17% of patients require renal replacement therapy (RRT). The most common cause of ARF early after LTx is ischemic acute tubular necrosis, followed later by cyclosporine toxicity and sepsis. Preoperative serum creatinine >1.5 mg/dL and early hepatic allograft dysfunction are risk factors for the occurrence of postoperative ARF. Of patients with ARF due to the hepatorenal syndrome, approximately two-thirds will recover, although recovery may be delayed 3 months or longer after LTx. Mortality after LTx is affected modestly by the presence of ARF pretransplant (<2-fold increase), but increases markedly (up to 8-fold) in the face of ARF posttransplant. Mortality does not appear to be influenced by the mode of RRT used. The risk of CKD after LTx is approximately 18% at 5 years and increases to approximately 25% by 10 years after transplantation. Calcineurin inhibitor toxicity is the most common cause. Specific prognosticators for predicting CKD after LTx are presently lacking. The occurrence of CKD after LTx markedly impairs long-term survival. 相似文献
63.
在常规治疗急性再生障碍性贫血 (AAA)基础上用大剂量的rhGM -CSF连续静脉给药 2w(5~ 15 μg kg.d)治疗 8例 ,并与常规治疗方法进行比较 ,研究结果表明 ,观察组较对照组外周血白细胞数增加 5~ 30倍。rhGM-CSF可以缓解AAA的临床症状 ,降低感染机会 ,是辅助治疗AAA的有效方法。 相似文献
64.
99Tcm-HL91乏氧显像脑缺血动物实验与初步临床研究 总被引:1,自引:0,他引:1
乏氧显像是近年来核医学显像的一种新技术。研究表明乏氧组织与正常组织的摄取比明显提高,可用于病灶组织缺血缺氧的判断。^99Tc^m作为一种新型乏氧组织显像剂能够选择性地滞留于缺血部位的脑组织中,通过SPECT显像可为脑缺血性疾病提供诊断信息。本研究通过脑缺血动物模型,探讨^99Tc^m在局部脑缺血模型脑组织中的分布特点,应用放射性自显影技术对局部脑缺血模型进行脑组织宏观放射性自显影研究。同时对21例急性脑梗塞患者进行了初步^99Tc^m脑显像观察。 相似文献
65.
Sbastien Larrch Jean-Philippe Chippaux Lucie Chevillard Simon Math Dabor Rsire Virginie Siguret Bruno Mgarbane 《International journal of molecular sciences》2021,22(17)
Toxins from Bothrops venoms targeting hemostasis are responsible for a broad range of clinical and biological syndromes including local and systemic bleeding, incoagulability, thrombotic microangiopathy and macrothrombosis. Beyond hemostais disorders, toxins are also involved in the pathogenesis of edema and in most complications such as hypovolemia, cardiovascular collapse, acute kidney injury, myonecrosis, compartmental syndrome and superinfection. These toxins can be classified as enzymatic proteins (snake venom metalloproteinases, snake venom serine proteases, phospholipases A2 and L-amino acid oxidases) and non-enzymatic proteins (desintegrins and C-type lectin proteins). Bleeding is due to a multifocal toxicity targeting vessels, platelets and coagulation factors. Vessel damage due to the degradation of basement membrane and the subsequent disruption of endothelial cell integrity under hydrostatic pressure and tangential shear stress is primarily responsible for bleeding. Hemorrhage is promoted by thrombocytopenia, platelet hypoaggregation, consumption coagulopathy and fibrin(ogen)olysis. Onset of thrombotic microangiopathy is probably due to the switch of endothelium to a prothrombotic phenotype with overexpression of tissue factor and other pro-aggregating biomarkers in association with activation of platelets and coagulation. Thrombosis involving large-caliber vessels in B. lanceolatus envenomation remains a unique entity, which exact pathophysiology remains poorly understood. 相似文献
66.
Julian Schwarting Kathrin Nehrkorn Hanhan Liu Nikolaus Plesnila Nicole Angela Terpolilli 《International journal of molecular sciences》2021,22(16)
Subarachnoid hemorrhage (SAH) is associated with acute and delayed cerebral ischemia. We suggested spasms of pial arterioles as a possible mechanism; however, it remained unclear whether and how pial microvasospasms (MVSs) induce cerebral ischemia. Therefore, we used in vivo deep tissue imaging by two-photon microscopy to investigate MVSs together with the intraparenchymal microcirculation in a clinically relevant murine SAH model. Male C57BL/6 mice received a cranial window. Cerebral vessels and leukocytes were labelled with fluorescent dyes and imaged by in vivo two-photon microscopy before and three hours after SAH induced by filament perforation. After SAH, a large clot formed around the perforation site at the skull base, and blood distributed along the perivascular space of the middle cerebral artery up to the cerebral cortex. Comparing the cerebral microvasculature before and after SAH, we identified three different patterns of constrictions: pearl string, global, and bottleneck. At the same time, the volume of perfused intraparenchymal vessels and blood flow velocity in individual arterioles were significantly reduced by more than 60%. Plugging of capillaries by leukocytes was observed but infrequent. The current study demonstrates that perivascular blood is associated with spasms of pial arterioles and that these spasms result in a significant reduction in cortical perfusion after SAH. Thus, the pial microvasospasm seems to be an important mechanism by which blood in the subarachnoid space triggers cerebral ischemia after SAH. Identifying the mechanisms of pial vasospasm may therefore result in novel therapeutic options for SAH patients. 相似文献
67.
Objective To develop a continuous arterial spin labeling (CASL) perfusion imaging method for cerebral blood flow (CBF) measurement in
rats with reduced spin-labeling length and optimized signal-to-noise ratio (SNR
f
) per unit time.
Materials and methods In the proposed method, the longitudinal magnetization of brain tissue water in the imaging slice is prepared into a proper
state before spin-labeling, and a post-tagging delay is employed after spin-labeling. The method was implemented on a 4.7 T
small animal scanner. Numerical simulations and in vivo experiments were used to evaluate the performance of the method proposed.
Results With the proposed method, absolute CBF could be measured accurately from normal rat with a spin-labeling pulse as short as
400 ms, and yet employing the same formula as that used in the conventional CASL perfusion imaging method for calculation.
The method also showed improved SNR
f
per unit time over the conventional CASL perfusion imaging method and the pulsed arterial spin labeling perfusion imaging
method FAIR.
Conclusion Compared to the conventional CASL perfusion imaging method, the proposed method would be advantageous for CBF measurement
in small animals having short vascular transit time in terms of SNR
f
per unit time and other benefits brought by shortened spin-labeling pulse. 相似文献
68.
Indigenous lactic acid fermented foods may have potential as probiotic treatment for diarrhoea, due to high levels of lactic acid bacteria. In this study the effect of a millet drink, spontaneously fermented by lactic acid bacteria, as a therapeutic agent among Ghanaian children with diarrhoea, was assessed. Children below 5 years of age coming to Northern Ghana health clinics for treatment of diarrhoea were randomised to two groups. Children of both groups received treatment for diarrhoea given at the local clinic. The intervention group in addition received up to 300 ml fermented millet drink (KSW) daily for 5 days after enrolment. The clinical outcome of diarrhoea and reported well-being were registered every day for the 5-day intervention and again 14 days after diagnosis. Among 184 children (mean age 17.4, standard deviation 11.3 months) included, no effects of the intervention were found with respect to stool frequency, stool consistency and duration of diarrhoea. However, KSW was associated with greater reported well-being 14 days after the start of the intervention (P = 0.02). The fact that no effect of KSW on diarrhoea was observed could be because many children had a mild form of diarrhoea, and many were treated with antibiotics. Either this could have affected the lactic acid bacteria, or the lactic acid bacteria in KSW had no probiotic effects. It is speculated that the effect after two weeks could be due to a preventing effect of KSW on antibiotic-associated diarrhoea which could help reducing persistent diarrhoea. 相似文献
69.
Sirvent AE Enríquez R Millán I García-Marco JM Rodríguez-Czaplicki E Redondo-Pachón MD González C Amorós F 《Hemodialysis international. International Symposium on Home Hemodialysis》2012,16(2):315-319
Mechanical complications of femoral catheterization for hemodialysis include pseudoaneurysm, arteriovenous fistulae, neurological injury, and vessel perforation. With regard to the latter, severe hemorrhage is a rare but devastating and potentially fatal complication. We report the case of a 76-year-old female who underwent femoral catheterization for hemodialysis using ultrasound guidance. The first hemodialysis session was conducted without incident. Unfortunately, inadvertent injury and delayed perforation of the iliac vein resulted in severe hemorrhage and retroperitoneal hematoma. Surgical repair was performed. The patient was asymptomatic after the procedure and was discharged 15 days later. Based on this case and a review of the literature, we present mechanisms and ways to prevent this complication. 相似文献
70.