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排序方式: 共有1688条查询结果,搜索用时 15 毫秒
1.
6-keto-prostaglandin F1a and thromboxane B2 were determined in order to obtain more information about the prostacyclin synthesis and thromboxane A2 release in 3- to 18-year-old healthy children and in offspring of parents who have had an acute myocardial infarction before the age of 45. The authors demonstrated a reduction of plasma prostacyclin synthesis in children with a positive family history of premature coronary arterial disease. Thromboxane levels in the affected adolescent boys were significantly lower compared with the controls. The ratio of thromboxane:prostacyclin in endangered children did not show a significant difference from that of healthy controls. These data indicate that prostaglandins are a definitive marker for identifying cardiovascular risk children. It must be supposed that in adolescence, only in boys, with a positive family history of premature coronary arterial disease, a compensatory mechanism exists to protect them from developing an imbalance in the regulation of prostaglandins. 相似文献
2.
Stomach rupture can occur as a consequence of the expansion of compressed air during rapid ascent after diving. We present
the case of a middle-aged woman who suffered a gastric tear from surfacing too quickly after diving, and discuss the diagnosis
and management of such patients by reviewing previously reported similar events. Gastric barotrauma should be suspected in
divers who complain of abdominal pain, even in the absence of frank signs of peritoneal irritation. Although pneumoperitoneum
is always present in these patients, it can also occur as a consequence of pulmonary barotrauma, making gastroscopy or radiological
contrast studies, or both, essential for a definitive diagnosis. Surgical repair represents the treatment of choice for an
active full-thickness tear and, if associated with arterial gas embolism or decompression sickness, should ideally be performed
in a center where a category I (intensive care-capable) hyperbaric unit is available.
Received: March 18, 2002 / Accepted: September 3, 2002
Reprint requests to: L.V. Titu 相似文献
3.
4.
Liviu Feller Neil H Wood Johan Lemmer 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(4):455-460
The use of highly active antiretroviral therapy (HAART) in the management of human immunodeficiency virus (HIV) infection has resulted paradoxically in the worsening of clinical symptoms of previously subclinical infections, such as herpes zoster (HZ), herpes simplex, angular cheilitis, warts, tuberculosis, hepatitis B and C, cytomegalovirus retinitis, and others, as a result of substantial reconstitution of the host's immune responses. This phenomenon is referred to as immune reconstitution inflammatory syndrome (IRIS). It may affect up to 32% of HIV-seropositive subjects within a wide range of time after the initiation of HAART, but mainly after 8-12 weeks. Mucocutaneous HZ accounts for 7%-12% of the diseases associated with HIV infection that become worse again when the subject's immunity improves from the administration of HAART. It usually occurs after 4 weeks from the initiation of HAART, and under these circumstances the clinical symptoms and natural course of mucocutaneous HZ are similar to those in HIV-seropositive subjects who do not manifest IRIS. 相似文献
5.
Evaluation of myocardial function in patients with end-stage heart failure during support with the Jarvik 2000 left ventricular assist device. 总被引:2,自引:0,他引:2
Markus Ferrari Kamuran A Kadipasaoglu Mihai Croitoru Jeff Conger Tim Myers Igor Gregoric Branislav Radovancevic George V Letsou O H Frazier 《The Journal of heart and lung transplantation》2005,24(2):226-228
In 2 patients with the Jarvik 2000 left ventricular assist device (LVAD), we assessed left ventricular systolic function through pressure-volume loops and E(max) at the beginning and end of the support period to potentially predict the possibility of pump removal without transplantation. Immediately before LVAD implantation and explantation, pressure and volume measurements were made with catheters and echocardiography, respectively, the E(max) being calculated from the slope of the pressure-volume loops, and the left ventricular ejection fraction (LVEF) being estimated by echocardiography. Transplantation was performed after 14 and 62 days, respectively, during which the LVEF increased by 75% (from 12% to 21%) in Patient 1 and remained unchanged (from 16% to 18%) in Patient 2, whereas the E(max) increased from 0.63 and 0.42 mm Hg/ml, respectively, to 1.31 and 1.07 mm Hg/ml, reflecting a 107% and 155% improvement. In these 2 cases, the E(max) was a more reliable indicator of intrinsic myocardial contractility than was the LVEF. 相似文献
6.
Mbaidjol Zacharia Stoffel Michael H. Frenz Martin Constantinescu Mihai A. 《Lasers in medical science》2021,36(4):855-862
Lasers in Medical Science - The common limitation of surgical revascularization procedures for severe tissue ischemia due to cardiovascular diseases is the need to interrupt blood flow during the... 相似文献
7.
Beatrice-Adriana Serban Mihai-Tudor Olaru Ioana-Cristina Badea Dumitru Mitrica Marian Burada Ioana Anasiei Mihai Ghita Albert-Ioan Tudor Cristian-Alexandru Matei Ana Maria Julieta Popescu Virgil Constantin Florina Branzoi Cristian Dobrescu Nicolae Constantin 《Materials》2022,15(17)
Materials used in the marine industry are exposed to extreme conditions, so it is necessary to meet remarkable characteristics, such as mechanical resistance, low density, and good corrosion resistance. The challenging environment requires continuous performance improvements, so this work is focused on developing new materials with superior properties, using the electrochemical deposition technique, which are convenient for marine engineering. High-entropy alloys have been attracting tremendous interest in many applications, due to their simple crystal structures and advantageous physical-chemical properties, such as high strength, anti-corrosion, erosion, and electro-magnetic capabilities. To identify the most appropriate compositions, MatCalc software was used to predict the structure and characteristics of the required materials, and thermodynamic and kinetic criteria calculations were performed. The modelling processes generated a series of optimal compositions in the AlCrCuFeNi alloy system, that are suitable to be used in anticorrosive and tribological applications. The composition and morphology of the obtained high entropy alloy thin films revealed a uniform structure, with a small grain profile. The corrosion resistance was investigated in artificial seawater to observe the behavior of the newly developed materials in demanding conditions, and the results showed improved results compared to the copper foil substrate. 相似文献
8.
Mariska Kerstholt Freek R van de Schoor Marije Oosting Simone J C F M Moorlag Yang Li Martin Jaeger Wouter A van der Heijden Rahajeng N Tunjungputri Jssica C dos Santos Brenda Kischkel Hedwig D Vrijmoeth M E Baarsma Bart-Jan Kullberg Mihaela Lupse Joppe W Hovius Cees C van den Wijngaard Mihai G Netea Quirijn de Mast Leo A B Joosten 《Clinical and experimental immunology》2022,210(1):53
Previous studies have shown that monocytes can be ‘trained’ or tolerized by certain stimuli to respond stronger or weaker to a secondary stimulation. Rewiring of glucose metabolism was found to be important in inducing this phenotype. As we previously found that Borrelia burgdorferi (B. burgdorferi), the causative agent of Lyme borreliosis (LB), alters glucose metabolism in monocytes, we hypothesized that this may also induce long-term changes in innate immune responses. We found that exposure to B. burgdorferi decreased cytokine production in response to the TLR4-ligand lipopolysaccharide (LPS). In addition, B. burgdorferi exposure decreased baseline levels of glycolysis, as assessed by lactate production. Using GWAS analysis, we identified a gene, microfibril-associated protein 3-like (MFAP3L) as a factor influencing lactate production after B. burgdorferi exposure. Validation experiments proved that MFAP3L affects lactate- and cytokine production following B. burgdorferi stimulation. This is mediated by functions of MFAP3L, which includes activating ERK2 and through activation of platelet degranulation. Moreover, we showed that platelets and platelet-derived factors play important roles in B. burgdorferi-induced cytokine production. Certain platelet-derived factors, such chemokine C-X-C motif ligand 7 (CXCL7) and (C-C motif) ligand 5 (CCL5), were elevated in the circulation of LB patients in comparison to healthy individuals. 相似文献
9.
This paper addressed the issues of both direct and indirect synthesis of Ni aluminides by pack cementation (pure Ni and IN 718 superalloy). On the Al-Ni diffusion twosome under pressure, at temperatures below and above the Al melting temperature, the appearance and evolution of diffusion porosity because of the Kirkendall–Frenkel effect manifestation was highlighted. It has been confirmed that, as the temperature rises above the Al melting temperature, the porosity decreases. Nickel-based superalloys, and in particular IN 718, significantly increase their performance by increasing the aluminides proportion in the top diffusion coating. This is made possible by changing the value of the Al and Ni weight percentage ratio in this area (noted as Al/Ni). In the case of the diffusion twosome between IN 718 and pack aluminizing mixtures, having in their composition as active components Al powder, Ferroaluminum (FeAl40) or mixtures of Al and Fe powders, at processing temperatures above the Al melting temperature, by modifying the active component of the mixture, substantial changes in the Al/Ni values were observed, as well as in the maximum %Al in the diffusion coating and of its thickness. It was found that, when switching from Al to FeAl40 or powder mixture (Al + Fe), the Al/Ni value changes between 3.43 and 1.01, from initial subunit values. The experiments confirmed that the highest %Al in the top aluminized diffusion coating, for IN 718, was obtained if the powder mixture contained 66.34 wt.% Al. 相似文献
10.
Adina Frum Carmen Maximiliana Dobrea Luca Liviu Rus Lidia-Ioana Virchea Claudiu Morgovan Adriana Aurelia Chis Anca Maria Arseniu Anca Butuca Felicia Gabriela Gligor Laura Gratiela Vicas Ovidiu Tita Cecilia Georgescu 《Nutrients》2022,14(15)
Grape pomace and berries represent natural sources of phytochemicals that can increase the quality of life of consumers by contributing to the prevention of chronic diseases; thus, the development of a dietary supplement was necessary. The raw material (r.m.) used for the development of the dietary supplement consisted of dried and powdered bilberries (Vaccinium myrtillus L.), red currants (Ribes rubrum L.), and red fermented pomaces (Vitis vinifera L.) from Feteasca Neagra and Cabernet Sauvignon cultivars. The particle size distribution, powder flow, total phenolic content (TPC), HPLC-DAD phenolic profile assessment, and radical scavenging assay (RSA) were employed for the analysis of the raw material. After encapsulation, the average mass and uniformity of mass, the disintegration, and the uniformity of content for the obtained capsules were performed to obtain a high-quality dietary supplement. All the assays performed complied to the compendial requirements and the TPC was determined at 9.07 ± 0.25 mg gallic acid equivalents/g r.m. and RSA at 48.32 ± 0.74%. The highest quantities of phenolic compounds determined were 333.7 ± 0.50 µg/g r.m. for chlorogenic acid, followed by rutin, ferulic acid, and (+)-catechin with 198.9 ± 1.60 µg/g r.m., 179.8 ± 0.90 µg/g r.m. and 118.7 ± 0.75 µg/g r.m., respectively. The results of this study can be used for the manufacturing and assessing of pilot scale-up capsule batches and thinking of quality assurance, we recommend that the industrial batch extracts should be standardized in polyphenols, and the manufacturing process should be validated. 相似文献