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141.
Saeed SA Shad KF Simjee SU 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,178(4):560-564
Thromboxane A2 (TXA2) formed in damaged brain tissue and after thromboembolism and subarachnoid haemorrhage is responsible for cerebral vasospasm.
In the present study, we examined the effect of human cerebrospinal fluid (CSF) on the production of thromboxane-A2 (TXA2) and 12-hydroxy-eicosatetraenoic acid (12-HETE) by human blood platelets. CSF was drawn by lumbar puncture from normal healthy
volunteers (n = 17) and samples judged to be normal after routine examination in the clinical laboratories and were used fresh. We found
that CSF inhibited the production of TXA2 and 12-HETE by blood platelets incubated with C14 labelled arachidonic acid (AA) in a concentration-related manner. Further biochemical analysis using proteolytic enzymes,
gel filtration and membrane partition chromatography showed that the inhibitory activity was peptidic in nature and associated
with a peptide of low molecular weight (1,400 Da). This study is the first to demonstrate that human CSF contains a dual inhibitor
of cyclooxygenase (COX) and lipoxygenase enzymes in CSF. 相似文献
142.
Mohammad Mahdi Majzoobi Seyyed Hamid Hashemi Mojgan Mamani Fariba Keramat Jalal Poorolajal Hamid Reza Ghasemi Basir 《International journal of antimicrobial agents》2018,51(3):365-369
Brucellosis is associated with a high recurrence rate and requires more than one course of standard treatment; therefore, more research is required to find more effective treatments that lead to prompt recovery, and reduce the relapse of disease. This single-blind, randomized study was designed to evaluate the effect of the standard treatment for brucellosis in combination with hydroxychloroquine.A total of 177 patients with acute brucellosis were randomly assigned to one of two treatment groups: doxycycline-streptomycin (DS) and doxycycline-streptomycin-hydroxychloroquine (DSH). Clinical symptoms and signs, serological tests, and side effects of therapy were compared between the two groups during the treatment course and at three and six months after the end of drug therapy. Of the 177 patients, with a mean age of 40.5?±?16.9 years, 66.1% were males. The mean duration of clinical signs prior to admission was 43.4?±?41.1 days. Appropriate clinical responses, relapse, treatment failure, and adverse drug reactions were seen in 98.9%, 1.2%, 0.0%, and 12.6% of patients, respectively, in the DSH group vs. 86.7%, 11.6%, 2.3%, and 19.8% of patients, respectively, in the DS group. There were significant differences in clinical response and relapse rates between the two groups. The addition of hydroxychloroquine to a doxycycline-streptomycin regimen appears to increase the efficacy of treatment, accelerate improvement of clinical symptoms, and significantly reduce the rate of relapse of brucellosis. 相似文献
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144.
Jasim Anwar Siranda Torvaldsen Mohamud Sheikh Richard Taylor 《Maternal and child health journal》2018,22(12):1743-1750
Objectives An enhanced surveillance system that integrated health information systems and extended surveillance to previously uncovered areas to capture all births, perinatal and maternal deaths in a rural district of Pakistan was established in 2015, and this study uses capture–recapture methodology to assess completeness. Methods Births and deaths collected by the survey were matched with the data captured by the enhanced surveillance system. Capture–recapture methodology was used to estimate the total number of births and deaths, measure the degree of underestimation, and adjust mortality rates. Results Of all births, 99% were captured by the enhanced surveillance system. Ninety percent of neonatal deaths and 86% of early neonatal deaths were recorded. The recorded neonatal mortality rate was 40 per 1000 live births (95% CI 35–44), and after adjustment for under-enumeration was 42 per 1000 live births (95% CI 37–46). Recorded rates underestimated neonatal mortality by 5% and perinatal mortality by 7%. Five stillbirths were recorded by the survey and all were matched to recorded stillbirths. The one maternal death recorded by the survey was matched with the maternal death captured by the enhanced surveillance system. The maternal mortality ratio prior to adjustment for under-enumeration was 247 per 100,000 live births (95% CI 147–391), whereas after adjustment it was 246 per 100,000 live births (95% CI 146–389). Conclusion Application of capture–recapture methods to the enhanced surveillance system indicated a high completeness of birth and death recording by the surveillance system. 相似文献
145.
Ebrahim Amini Hamid Reza Marzban Mahdi Rastegari 《Optimal control applications & methods.》2020,41(5):1735-1748
By going to millimeter wave (mmWave) we can use large scale MIMO due to short mmWave wavelength to overcome path loss by using beamforming to focus power of signal to the receiver. System structure of mmWave band is different with conventional MIMO because of large scale MIMO which is leading to use many RF-chains. For this reason Hybrid structure have been proposed for large Scale MIMO. By going to Hybrid structure a new issue has been created with phase shifter constraint. In this paper we propose a novel solution to make a hybrid precoding and combing to reach high spectral efficiency. Our problem includes a maximizing Frobenius norm of multiplying five complex matrices. As constraints, all elements of some matrices must have unit norm, and also the multiplication of some matrices must have a specific Frobenius norm. A novel solution is proposed for the problem, which is gained in two steps. At the first step, we propose a new decomposition usable for kind of complex matrices which could lead to reduce the dimension of the objective function, and eliminating constraints completely and in the second step, we propose an iterated algorithm for the resulting problem. By proposing another novel technique, we show that in each iteration, the optimal problem is equivalent to a quadratic optimal problem with limitations on the vector norm, and as a result, an optimal problem is obtained quickly. Moreover, some other real examples are included to demonstrate the usefulness and effectiveness of the proposed algorithm. 相似文献
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147.
Mahdi Azarabadi Fatemeh Heidari Amir Afshin Khaki Gholamreza Kaka Alireza Ghadian 《Andrologia》2020,52(9):e13704
Testicular torsion is a serious urological disease leading to testicular damage. This study aimed to assess the effect of minocycline on testicular ischaemia/reperfusion (I/R) injury caused by testicular torsion/detorsion. Male adult Wistar rats (n = 32) were assigned into four groups of sham, I/R, I/R + minocycline and minocycline. I/R injury was induced by two sets of surgical operations, including the rotation of the left testis (720°, counterclockwise), followed by detorsion after 4 hr. The administration of minocycline was carried out 30 min before detorsion and then continued for 8 weeks. At the end of the 8th week, rats were killed and sampling was done. Johnson's score, the height of seminiferous tubule epithelium, the mean seminiferous tubule diameter, as well as biochemical parameters, SOD, GPx and CAT, were significantly enhanced in the I/R + minocycline group compared with the I/R group. The administration of minocycline led to a marked decrease in expression levels of Caspase-3, Bax, IL-1β and TNF-α genes, and a remarkable increase in expression levels of Bcl-2, 3β-HSD and 17β-HSD3 genes compared with the I/R group. Administration of minocycline could also reduce the rate of germ cell apoptosis (TUNEL staining). Hence, minocycline was useful in the management of testicular torsion/detorsion. 相似文献
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150.
Mohammad Nishat Akhtar Muneer Khan Sher Afghan Khan Asif Afzal Ram Subbiah Sheikh Nazir Ahmad Murtuja Husain Mohammad Mursaleen Butt Abdul Rahim Othman Elmi Abu Bakar 《Materials》2021,14(10)
In the present investigation, the non-recrystallization temperature (TNR) of niobium-microalloyed steel is determined to plan rolling schedules for obtaining the desired properties of steel. The value of TNR is based on both alloying elements and deformation parameters. In the literature, TNR equations have been developed and utilized. However, each equation has certain limitations which constrain its applicability. This study was completed using laboratory-grade low-carbon Nb-microalloyed steels designed to meet the API X-70 specification. Nb- microalloyed steel is processed by the melting and casting process, and the composition is found by optical emission spectroscopy (OES). Multiple-hit deformation tests were carried out on a Gleeble® 3500 system in the standard pocket-jaw configuration to determine TNR. Cuboidal specimens (10 (L) × 20 (W) × 20 (T) mm3) were taken for compression test (multiple-hit deformation tests) in gleeble. Microstructure evolutions were carried out by using OM (optical microscopy) and SEM (scanning electron microscopy). The value of TNR determined for 0.1 wt.% niobium bearing microalloyed steel is ~ 951 °C. Nb- microalloyed steel rolled at TNR produce partially recrystallized grain with ferrite nucleation. Hence, to verify the TNR value, a rolling process is applied with the finishing rolling temperature near TNR (~951 °C). The microstructure is also revealed in the pancake shape, which confirms TNR. 相似文献