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排序方式: 共有835条查询结果,搜索用时 11 毫秒
1.

This study aimed to examine the side effects of selected neonicotinoids (Acetamiprid, Aceta, and Imidacloprid, Imid) on Oreochromis niloticus juveniles. The acute toxicity, Probit method, revealed an LC50 of 195.81 and 150.76 ppm for Aceta/96 h and Imid/72 h respectively. The fish were divided into three groups that were exposed, for 21 days (n?=?5/replicate), to 1/10 of the LC50 of either neonicotinoids, however, the third was an unexposed control group. Results of erythrocytic micronucleus (MN), and nuclear abnormalities (NA) showed that Aceta and Imid exposure caused a significant (p?<?0.05) increase in MN by?~?2.2 and?~?10 folds, respectively relative to control. NAs occurred at the order of kidney-shaped?>?budding?>?binucleated in Aceta, however, budding?>?binucleated?>?kidney-shaped was noticed in the Imid group. Histopathological changes in gills, liver, and muscles were observed significantly in both exposed groups with more severity in the Imid group. Collectively, Aceta and Imid have potential genotoxicity and histopathological alterations in O. niloticus.

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2.
We previously isolated an HSV-1 mutant, KOS-NA, that contains two non-synonymous mutations in UL39. One of the mutations, resulting in an R950H amino acid substitution in ICP6, renders KOS-NA severely neuro-attenuated and significantly reduces HSV-1 latency. Vaccination of mice with KOS-NA prior to corneal challenge provides significant protection against HSV-1-mediated eye diseases even at a very low immunizing dose, indicating its utility as a vaccine scaffold. Because KOS-NA contains a neuro-attenuating mutation in a single gene, we sought to improve its safety by deleting a portion of the UL29 gene whose protein product, ICP8, is essential for viral DNA replication. Whereas KOS-NA reduced replication of HSV-1 challenge virus in the corneal epithelium and protected mice against blepharitis and keratitis induced by the challenge virus, KOS-NA/8- and an ICP8- virus were significantly less efficacious except at higher doses. Our results suggest that the capacity to replicate, even at significantly reduced levels compared with wild-type HSV-1, may be an important feature of an effective vaccine. Means to improve safety of attenuated viruses as vaccines without compromising efficacy should be sought.  相似文献   
3.
Asthma represents a globally serious non-communicable ailment with significant public health outcomes for both pediatrics and adults triggering vast morbidity and fatality in critical cases. The β2-adrenoceptor agonist, terbutaline sulfate (TBN), is harnessed as a bronchodilator for monitoring asthma noising symptoms. Nevertheless, the hepatic first-pass metabolism correlated with TBN oral administration mitigates its clinical performance. Likewise, the regimens of inhaled TBN dosage forms restrict its exploitation. Consequently, this work is concerned with the assimilation of TBN into a novel non-phospholipid nanovesicular paradigm termed novasomes (NVS) for direct and effective TBN pulmonary targeting. TBN-NVS were tailored based on the thin film hydration method and Box-Behnken design was applied to statistically optimize the formulation variables. Also, the aerodynamic pattern of the optimal TBN-NVS was explored via cascade impaction. Moreover, comparative pharmacokinetic studies were conducted using a rat model. TBN elicited encapsulation efficiency as high as 70%. The optimized TBN-NVS formulation disclosed an average nano-size of 223.89 nm, ζ potential of −31.17 mV and a sustained drug release up to 24 h. Additionally, it manifested snowballed in vitro lung deposition behavior in cascade impactor with a fine particle fraction of 86.44%. In vivo histopathological studies verified safety of intratracheally-administered TBN-NVS. The pharmacokinetic studies divulged 3.88-fold accentuation in TBN bioavailability from the optimum TBN-NVS versus the oral TBN solution. Concisely, the results proposed that NVS are an auspicious nanovector for TBN pulmonary delivery with integral curbing of the disease owing to target specificity.  相似文献   
4.
A novel series of glass, consisting of B2O3, Bi2O3, TeO2, and TiO2 (BBTT) containing rare earth oxide RE2O3, where RE is La, Ce, Sm, Er, and Yb, was prepared. We investigated the structural, optical, and gamma attenuation properties of the resultant glass. The optical energy bands, the linear refractive indices, the molar refractions, the metallization criteria, and the optical basicity were all determined for the prepared glass. Furthermore, physical parameters such as the density, the molar volume, the oxygen molar volume, and the oxygen packing density of the prepared glass, were computed. Both the values of density and optical energy of the prepared glass increased in the order of La2O3, Ce2O3, Sm2O3, Er2O3, and then Yb2O3. In addition, the glass doped with Yb2O3 had the lowest refractive index, electronic polarizability, and optical basicity values compared with the other prepared glass. The structures of the prepared glass were investigated by the deconvolution of infrared spectroscopy, which determined that TeO4, TeO3, BO4, BO3, BiO6, and TiO4 units had formed. Furthermore, the structural changes in glass are related to the ratio of the intensity of TeO4/TeO3, depending on the type of rare earth. It is also clarified that the resultant glass samples are good attenuators against low-energy radiation, especially those that modified by Yb2O3, which exhibited superior shielding efficiency at energies of 622, 1170, and 1330 keV. The optical and gamma ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optical fibers, laser solid material, and optical shielding protection.  相似文献   
5.
BackgroundCoronavirus disease (COVID‐19) is an infectious disease caused by SARS COV‐2 that has spread globally, the virus can cause different pathological alterations in many organs, such as the lung, kidney, and testis. The study aimed to determine the effect of COVID‐19 on the seminal fluid parameters of infected infertile males compared with those who are noninfected.MethodsThe study was performed in Al‐Hussein Teaching Hospital during the period from September to November, 2021 and it involved 318 patients. The patients’ info included age, address, and vaccination. The sperm count, activity, and morphology were detected using Computer‐assisted semen analysis CASA (Microptic‐Spain) according to the WHO manual.ResultsThere were high significant differences between the infertile males who were infected with COVID‐ 19 and those who were vaccinated (X 2 = 12.509, p = 0.001). A high significant relation (p < 0.001) was recorded between types of infection severity and volume of semen (p < 0.001) and nonprogress life sperm (C) (p < 0.001). While significant differences were shown in the moderate progression sperm (B) (p = 0.012), and morphology (p = 0.02), respectively. High significant differences were reported between the types of infection severity (count of the sperm, presence of pus, B, C and D), (p < 0.001), while a significant difference was shown between severity types in relation to A and morphology of the sperms (p = 0.021 and 0.015), respectively.ConclusionThe severity of COVID‐19 has a significant impact on infertility and sperm parameters, particularly progression and sperm morphology, despite the fact that these parameters are unrelated to vaccination.  相似文献   
6.
In this study, the X-ray and gamma attenuation characteristics and optical properties of a synthesized tellurite–phosphate–sodium oxide glass system with a composition of (85 − x)TeO2–10P2O5–xNa2O mol% (where x = 15, 20, and 25) were evaluated. The glass systems we re fabricated by our research group using quenching melt fabrication. The shielding parameters of as-synthesized systems, such as the mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), effective atomic number (Zeff), half-value layer (HVL), tenth value layer (TVL), mean free path (MFP), and effective electron density (Neff) in a wide energy range between 15 keV and 15 MeV, were estimated using well-known PHY-X/PSD software and recently developed MIKE software. Herein, the optical parameters of prepared glasses, such as molar volume (VM), oxygen molar volume (VO), oxygen packing density (OPD), molar polarizability (αm), molar refractivity (Rm), reflection loss (RL), and metallization (M), were estimated using MIKE software. Furthermore, the shielding performance of the prepared glasses was compared with that of commonly used standard glass shielding materials. The results show that the incorporation of sodium oxide into the matrix TeO2/P2O5 with an optimum concentration can yield a glass system with good shielding performance as well as good optical and physical properties, especially at low photon energy.  相似文献   
7.
Soft tissue chondroma is an uncommon soft-tissue cartilaginous tumor of benign nature, it considers a variant of extra-skeletal chondromas that undergoes extensive ossification. This case of a 37?years old Egyptian male presented with a recurrent slowly growing painful palpable heel mass arises at the plantar aspect of his RT foot.The case is pathologically proven to be benign soft tissue chondroma.  相似文献   
8.
Hydroferrate fluid, MRN-100, an iron-based compound derived from bivalent and trivalent ferrates, is a potent antioxidant compound. Therefore, we examined the protective effect of MRN-100 against γ-radiation-induced lethality and damage to hematopoietic tissues in fish. A total of 216 Nile tilapia fish (Oreochromis niloticus) were randomly divided into four groups. Group 1 served as a control that was administered no radiation and no MRN-100 treatment. Group 2 was exposed only to γ-radiation (15 Gy). Groups 3 and 4 were pre-treated with MRN-100 at doses of either 1 ml/l or 3 ml/l in water for 1 week, and subsequently exposed to radiation while continuing to receive MRN-100 for 27 days. The survival rate was measured, and biochemical and histopathological analyses of hematopoietic tissues were performed for the different treatment groups at 1 and 4 weeks post-radiation. Exposure to radiation reduced the survival rate to 27.7%, while treatment with MRN-100 maintained the survival rate at 87.2%. In addition, fish exposed to γ-radiation for 1 week showed a significant decrease in the total number of white blood cells (WBCs) and red blood cells (RBCs) series. However, treatment with MRN-100 protected the total WBC count and the RBCs series when compared with irradiated fish. Furthermore, significant histological lesions were observed in the hepatopancreas, spleen and gills of irradiated fish. However, treatment with MRN-100 protected the histopathology of various organs. We conclude that MRN-100 is a radioprotective agent in fish and may be useful as an adjuvant treatment to counteract the adverse side effects associated with radiation exposure.  相似文献   
9.
Metabolic Brain Disease - Stroke is a lethal event with a high incidence in Egypt. Quick early intervention can be lifesaving. Transient global ischemia (TGI), a type of ischemic stroke, is mainly...  相似文献   
10.

Background

Till now, pooled data about the safety and efficacy of different direct-acting antiviral (DAAs) regimens in different renal situations are still under evaluation.

Aim

To evaluate a real-life experience of the efficacy and safety of ombitasvir/paritaprevir/ritonavir plus ribavirin (OBV/PTV/r plus RIB) in patients with end-stage kidney disease (ESKD).

Patients and methods

Between January 2017 and January 2018, an open-label multicenter prospective study was designed to enroll all consecutive patients with proven CHC genotype 4 infections and concomitant ESKD based on estimated glomerular filtration rate (eGFR) with (HD group) or without hemodialysis (non-HD group). Patients were given a co-formula of OBV/PTV/r (25/150/100?mg) once-daily plus RIB was given for 12?weeks. Sustained virologic response (SVR 12) was the primary endpoint.

Results

A total of 110 patients were enrolled. An overall SVR 12 was reported in 104 (94.5%) patients, and treatment failure were reported in 6 patients [2 patients (1.8%) were relapsed, and 4 patients (3.6%) patients were non-responders]. SVR12 was 96% in HD and 91.4% in non-HD patients (P?=?0.286).There were no reported serious adverse events. Anemia was reported in 66.6% (n?=?50) in HD group and in 31.4% (n?=?11) in non-HD group.

Conclusion

Although it is still challenging, achievement of SVR12 in patients with chronic HCV and concomitant end-stage kidney disease in the era of DAAs became possible with a 12?weeks course of a co-formula of ombitasvir/paritaprevir /ritonavir plus ribavirin.

ClinicalTrials.gov ID

NCT03341988.  相似文献   
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