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排序方式: 共有6233条查询结果,搜索用时 10 毫秒
41.
Amin Sadeghi Dousari Seyed Soheil Hosseininasab Fatemeh Sadeghi Dousari Masoumeh Fuladvandi Naghmeh Satarzadeh 《World Journal of Virology》2023,12(2):91-99
The coronavirus disease 2019 (COVID-19) disease was first detected in December 2019 in Wuhan, China. This disease is currently one of the most important global health problems. The novel coronavirus COVID-19 is a respiratory illness, that has caused a deadly pandemic that is spreading rapidly around the world. It is not only a respiratory system virus that causes severe lung disease, but also a systemic disease agent that can affect all systems. People with COVID-19 disease usually have respiratory signs, however, the liver disorder is not an uncommon presentation. In addition, many studies around the world have revealed that the liver is injured to various degrees in patients with severe acute respiratory syndrome coronavirus 2 disease. This review mainly focuses on the impact of COVID-19 on Liver Injury at various ages. 相似文献
42.
Amin Afrazi Sylvana Garcia-Rodriguez James D Maloney Clinton T Morgan 《Interactive Cardiovascular and Thoracic Surgery》2021,32(1):150
Severe respiratory sequelae drive morbidity-associated with coronavirus 2019 (COVID-19) disease. We report a case of COVID-19 pneumonia complicated by cavitary lesions and pneumothorax in a young healthy male. Pneumothorax management with catheter thoracostomy and rapid resolution of the cavitary lesions are described. An extensive work-up for other causes a cavitation was negative and the temporal correlation of the cavities with COVID-19 infection plus their rapid resolution suggest a direct relationship. We propose a mechanism for cavitation secondary to microangiopathy, a cause of cavitation in the vasculitides and a known feature of COVID-19. 相似文献
43.
Natural Convection Heat Transfer in a Porous Cavity with Sinusoidal Temperature Distribution Using Cu/Water Nanofluid: Double MRT Lattice Boltzmann Method 下载免费PDF全文
Hasan Sajjadi Amin Amiri Delouei Rasul Mohebbi Mohsen Izadi & Sauro Succi 《Communications In Computational Physics》2021,29(1):292-318
In this study, natural convection flow in a porous cavity with sinusoidal
temperature distribution has been analyzed by a new double multi relaxation time
(MRT) Lattice Boltzmann method (LBM). We consider a copper/water nanofluid filling a porous cavity. For simulating the temperature and flow fields, D2Q5 and D2Q9
lattices are utilized respectively, and the effects of different Darcy numbers (Da) (0.001-0.1) and various Rayleigh numbers (Ra) ($10^3$-$10^5$) for porosity ($ε$) between 0.4 and 0.9
have been considered. Phase deviation ($θ$) changed from 0 to $π$ and the volume fraction
of nanoparticles (Ø) varied from 0 to 6%. The present results show a good agreement
with the previous works, thus confirming the reliability the new numerical method
proposed in this paper. It is indicated that the heat transfer rate increases at increasing
Darcy number, porosity, Rayleigh number, the volume fraction of nanoparticles and
phase deviation. However, the most sensitive parameter is the Rayleigh number. The
maximum Nusselt deviation is 10%, 32% and 33% for Ra=$10^3$, $10^4$ and $10^5$, respectively, with $ε = 0.4$ to $ε = 0.9$. It can be concluded that the effect of Darcy number on
the heat transfer rate increases at increasing Rayleigh number, yielding a maximum
enhancement of the average Nusselt number around 12% and 61% for Ra=$10^3$ and
Ra=$10^5$, respectively. 相似文献
44.
Bhat IA Amin S Shah GN 《Indian journal of maternal and child health : official publication of Indian Maternal and Child Health Association,》1997,8(1):5-8
The nutritional status of 584 preschool children in an urban slum of Srinagar district was assessed through interviews of mothers conducted in a house-to-house survey, the clinical assessment of child nutritional status, and the anthropometric measurement of the children using accepted standard techniques. The anthropometric measurements of the children were compared to the 50th percentile of the Harvard Standard, while the classification recommended by the Indian Academy of Pediatrics was adopted for the categorization and grading of protein energy malnutrition. 60.45% of the children were malnourished, comprised of 33.22%, 20.89%, and 6.34% of children with grade I, II, and III degrees of malnutrition, respectively. Higher prevalence of malnutrition is associated with higher age, female sex, lower per capita income, higher birth order, and lower parental literacy. Parental literacy status followed by birth order and per capita income were the most important factors associated with preschool child malnutrition. 相似文献
45.
Primary malignant non-Hodgkin's lymphomas account for 0.4% of malignant neoplasms arising in the bladder and female urethra, but do not comprise a uniform group, and three subgroups can be identified which account for a majority of cases. The most common is a low-grade B-cell lymphoma similar to neoplasms arising in the mucosa-associated lymphoid tissue at other sites — so-called MALTomas. These generally display indolent behavior. A second group accounting for approximately one-fifth of cases is composed almost entirely of large lymphoid cells, and these tumors have a poor prognosis. A third possible group comprises only a few patients who present with diffuse thickening of the bladder wall, and have a poor prognosis. The authors present a new case which suggests that this latter group may be of T-cell origin. In addition to these three subtypes, others no doubt await recognition. The different forms of primary lymphoma appear to require different treatments, and some guidelines are proposed. 相似文献
46.
B. P. Imbimbo T. Mant M. Edwards D. Amin N. Dalton F. Boutignon V. Lenaerts P. Wüthrich R. Deghenghi 《European journal of clinical pharmacology》1994,46(5):421-425
Hexarelin is a new hexapeptide (His-d-2-methyl-Trp-Ala-Trp-d-Phe-Lys-NH2) that stimulates the release of growth hormone both in vitro and in vivo. In this double-blind, placebo-controlled, rising-dose study we evaluated the growth hormone releasing activity of hexarelin in healthy human subjects. Twelve adult male volunteers received single intravenous boluses of 0.5, 1 and 2 ·g·kg–1 hexarelin as well as placebo. For safety, drug doses were given in a rising-dose fashion with placebo randomly inserted into the sequence. Plasma growth hormone concentrations increased dose-dependently after the injection of the peptide, peaking at about 30 min and then decreasing to baseline values within 240 min with a half-life of about 55 min. The mean peak plasma growth hormone concentrations (Cmax) were 3.9, 26.9, 52.3, 55.0 ng·ml–1 after 0, 0.5, 1 and 2 g·kg–1, respectively. The corresponding areas under the curve of growth hormone plasma levels from drug injection to 180 min (AUC0–180) were 0.135, 1.412, 2.918 and 3.695 g·min·ml–1. The theoretical maximum response (Emax) and the dose that produces half of the maximum response (ED50) were estimated using logistic regression. The calculated ED50 values were 0.50 and 0.64 g·kg–1 for Cmax and AUC0–180, respectively. The corresponding Emaxs were 55.1 ng·ml–1 and 3936 ng·min·ml–1, thus indicating that the effect after the 2 g·kg–1 dose is very close to the maximal response. Plasma glucose, luteinising hormone, follicle-stimulating hormone, thyroid-stimulating hormone and insulin-like growth factor I were unaffected by hexarelin administration, while the peptide caused a slight increase in prolactin, cortisol and adrenocorticotropic hormone levels. Hexarelin was well tolerated in all subjects. The results of this study indicate that intravenous administration of hexarelin in man produces a substantial and dose-dependent increase of growth hormone plasma concentrations. 相似文献
47.
Ruhul AM Fukuda H Nakajima K Takatorige T Tatara K 《Environmental health and preventive medicine》1999,4(2):65-70
Health is one of the basic requirements for improvement in the quality of life. Since Bangladesh became independent, a policy
for providing essential minimum health care to all has been actively pursued.
An overview of Public Health Services in Bangladesh is presented in terms of: (1) a profile of the country, (2) an overview
of public health, (3) medical care, and (4) environmental health. Under each of these headings observations are included on
recent trends based upon relevant data and information.
Finally the authors describe the importance of (1) promotion of health care and planning at the national, divisional, local,
and community levels, (2) promotion of medical services at all levels, and (3) effective decentralization of health services
to enhance the services of health facilities. 相似文献
48.
49.
The effect of hyperbaric oxygen on medial collateral ligament healing in a rat model 总被引:1,自引:0,他引:1
Horn PC Webster DA Amin HM Mascia MF Werner FW Fortino MD 《Clinical orthopaedics and related research》1999,(360):238-242
Hyperbaric oxygen has been shown to promote healing in bone and some soft tissues. This study was undertaken to determine its effect on ligamentous healing. Forty-eight Sprague-Dawley rats underwent a standardized surgical laceration of the right (divided) medial collateral ligament, whereas the left (undivided) medial collateral ligament was not surgically lacerated. A control group of 24 rats recovered without intervention. An experimental group consisting of the other 24 rats was exposed to hyperbaric oxygen at 2.8 atmospheres for 1.5 hours a day for 5 days after the surgery. Six rats from each group were euthanized at 2, 4, 6, and 8 weeks. The stiffness and final force to failure were recorded for the divided and undivided medial collateral ligaments. At 4 weeks, a statistically greater force was required to cause failure of the previously divided ligaments that had been exposed to hyperbaric oxygen than those that had not. The stiffness and force to cause failure of previously divided ligaments were statistically greater at 4 weeks than at 2 weeks, whether or not hyperbaric oxygen was used. No additional statistical increases in stiffness or force were observed at 6 weeks. 相似文献
50.
Amin MB de Peralta-Venturina MN Ro JY El-Naggar A Mackay B Ordonez N Mani A Ayala A 《The American journal of surgical pathology》1999,23(12):1455-1463
Clear cell sarcoma of the kidney is a distinct, highly malignant pediatric neoplasm. Its occurrence in adults is extremely rare and the subject of isolated case reports. We present a series of four cases (three males and one female) identified in an adolescent and in young adults (16, 18, 20, and 25 years) with flank mass (three cases), hematuria (two cases), flank pain (two cases), and hypertension (one case). Three patients had stage III disease and one had stage I disease (National Wilms' Tumor Study staging system). All tumors had predominantly or exclusively the classic histology of a monotonous proliferation of uniform small round cells with evenly distributed fine chromatin, although focal microcyst formation (two cases) and spindled architecture (one case) (variant patterns) were also noted. Therapy in all cases consisted of surgery and chemotherapy with or without radiation. Follow-up data (29-202 months) showed distant metastases in all four cases, including the lung (four cases), bone (two cases), and the liver (two cases). Three patients died of disease at 29, 59, and 63 months (mean, 50.3 months), and one patient is alive with no evidence of disease at 202 months. Ultrastructural features included scattered primitive junctions, short and irregular cytoplasmic extensions, and scant to a moderate amount of mitochondria. Immunohistochemical study (three cases) showed immunoreactivity with vimentin (two cases) and no reaction with cytokeratin, epithelial membrane antigen, S-100 protein, or desmin. Flow cytometric analysis showed diploid DNA content in three primary tumors and tetraploidy in one metastatic tumor. The proliferative activity (S-phase fraction) was low to intermediate (mean, 9.8%). Our data suggest that clear cell sarcoma of the kidney in the young adult age group resembles its pediatric counterpart in ultrastructural and immunohistochemical characteristics, proclivity for skeletal and visceral metastasis, DNA diploid status with relatively low S-phase, and aggressive clinical course. Clear cell sarcoma of the kidney in adult patients, although rare, must be differentiated from sarcomatoid carcinoma, sarcomas, and round cell tumors because of its unique characteristics in comparison to other renal neoplasms. 相似文献