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81.
Acetaminophen overdose causes severe hepatotoxicity leading to liver failure in experimental animals and humans. This study was undertaken to evaluate the protective effect of kombucha tea (KT) against acetaminophen-induced hepatotoxicity. Forty male Balb/c mice were divided into four equal groups: (1) the control group, (2) KT-treated group, (3) acetaminophen-treated group, and (4) KT/acetaminophen-treated group. All mice in group 4 were given KT orally for 7?days before a single hepatotoxic dose of acetaminophen (1,000?mg/kg orally). Activities of liver marker enzymes in serum; aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP); and total protein (TP), albumin (ALB), and direct and total bilirubin levels were determined. Acetaminophen challenge caused significant increases in the levels of bilirubin and liver enzymes (AST, ALT, ALP, and LDH), while TP and ALB levels were reduced significantly. Histopathologic assessments showed that severe glycogen storage in hepatocytes, hepatocellular degeneration and necrosis, mononuclear cell infiltration in portal area, dilation of central veins, and capillarization also reduced in KT/acetaminophen group compared to acetaminophen-treated mice. In conclusion, these findings suggest that KT has protective effect on acetaminophen-induced hepatotoxicity.  相似文献   
82.
We propose a novel drug delivery system (DDS) by using a PANDA ring resonator to form, transmit and receive the microscopic volume by controlling some suitable ring parameters. The optical vortices (gradient optical field/well) can be generated and used to form the trapping tool in the same way as the optical tweezers. The microscopic volume (drug) can be trapped and moved (transported) dynamically within the wavelength router or network. In principle, the trapping force is formed by the combination between the gradient field and scattering photons, which has been reviewed. The advantage of the proposed system is that a transmitter and receiver can be formed within the same system, which is called transceiver, in which the use of such a system for microscopic volume (drug volume) trapping and transportation (delivery) can be realized.OCIS codes: (140.7010) Laser trapping, (350.4855) Optical tweezers or optical manipulation, (080.4865) Optical vortices, (140.4780) Optical resonators, (190.4360) Nonlinear optics, devices  相似文献   
83.
84.
85.

Background

The purpose of this study was to compare the incidence of iatrogenic anterior retinal breaks in 20-G vitrectomy (PPV) with transconjunctival 23-G PPV.

Methods

Retrospective, observational review study involving consecutive patients undergoing PPV in a single center in the UK during a 2-year period.

Results

Sclerotomy-related entry-site breaks (ESB) were found in 50/628 (7.9 %) 20-G PPV cases and 5/296 (1.7 %) 23-G PPV eyes (p?<?0.0001*). Anterior non-sclerotomy iatrogenic breaks (ANSB) were present in 55/628 (8.7 %) 20-G PPV cases and 18/296 (6.1 %) 23-G PPV eyes (p?=?0.19). The incidence of total anterior iatrogenic breaks (ANSB?+?ESB) was 105/628 (16.7 %) for 20-G PPV and 23/296 (7.8 %) for 23-G PPV (p?=?0.002*). Univariate analysis showed that posterior vitreous detachment induction was the only risk factor significantly associated with the development of anterior retinal breaks for both 20-G and 23-G PPV. Multivariate logistic model of risk factors for development of iatrogenic retinal breaks demonstrated that 23-G PPV was the most important factor reducing the risk of anterior breaks (p?<?0.0001*).

Conclusions

We report the largest series of patients undergoing 20-G and 23-G vitrectomy, where 23-G vitrectomy was associated with a significantly lower incidence of anterior iatrogenic retinal breaks.  相似文献   
86.
Mixed micellar nanoparticle consisting of amphotericin B (AmB) and poly styrene-block-poly ethylene oxide (PS-block-PEO) was prepared by high pressure homogenizer. Nephrotoxicity of the nanoparticle was investigated along with antifungal activity and self-aggregation status of the drug in the nanoparticle. Nephrotoxicity was markedly reduced when AmB was intravenously administered to rats as mixed micellar nanoparticle with PS-block-PEO in terms of transmission electron microscopy of tubular cells and creatinine clearance. Antifungal activity of AmB was not altered when the drug was in the form of mixed micellar nanoparticle compared to both conventional formulation and AmB micelle treated by same procedure without PS-block-PEO. Self-aggregation status of AmB molecules revealed monomeric in the mixed micellar nanoparticle with PS-block-PEO up to the therapeutic level of the drug (1-3 mM). The reduced nephrotoxicity of AmB in mixed micellar nanoparticle may be associated with the existence of the drug as monomeric form in the nanoparticle. Based on our result, formulation of AmB as mixed micellar nanoparticle with PS-block-PEO may be a promising alternative for the treatment of fungal diseases in patients who are at risk of renal dysfunction.  相似文献   
87.

Objective

To determine the bionomics and susceptibility status of the malarial vector Anopheles superpictus (An. superpictus) to different insecticides in the Sistan-Baluchestan province which has the highest malarial prevalence in Iran.

Methods

Different sampling methods, in addition to scoring abdominal conditions, were used to define the seasonal activity and endo/exophilic behavior of this species. In addition, the standard WHO susceptibility tests were applied on adult field strains.

Results

Most adult mosquitoes were collected from outdoor shelters. The peak of seasonal activity of An. superpictus occurred at the end of autumn. Most larvae were collected from natural and permanent breeding places with full sunlight and no vegetation. Blood feeding activities occurred around midnight. Compared with the abdominal conditions of adult mosquitoes collected indoors, the abdominal conditions of adult mosquitoes collected outdoors were gravid and semigravid. This species was suspected to be resistant to DDT, but was susceptible to other insecticides.

Conclusions

An. superpictus was present in almost all outdoor shelters, and the ratios of gravid, semigravid/unfed, and freshly fed confirmed that this species had a higher tendency to rest outdoors than indoors. This behavior can protect An. superpictus from indoor residual spraying in this malarious area. To the best of our knowledge, this is the first report on the susceptibility status of An. superpictus in Southeastern Iran. We do not suggest the use of DDT for indoor residual spraying in southeast Iran.  相似文献   
88.
In the course of our search for novel platelet-activating factor (PAF) antagonists from medicinal plants, the methanol extract of the leaves of Ardisia elliptica Thunb. was investigated for its inhibitory effects on PAF receptor binding to rabbit platelets using 3H-PAF as a ligand. The methanol extract showed inhibitory activity of 53.9% and its ethyl acetate, n-butanol, and methanol fractions exhibited 48.6%, 39.0%, and 22.0% inhibition, respectively. Bioassay-guided fractionation of the ethyl acetate fraction led to the isolation of a new alkenylresorcinol, 5-(Z-heptadec-4′-enyl)resorcinol, together with 5-pentadecylresorcinol. The alkenylresorcinol showed a strong inhibition with an IC50 value of 7.1 µM. The structures of the compounds were elucidated by spectroscopic techniques.  相似文献   
89.
90.

Background

Patellar dislocations are a commonly treated injury in the Emergency Department (ED), with a majority of cases involving lateral subluxation of the patella outside of the joint space. Intra-condylar dislocations of the patella are rare. Of the two types of axis rotation, vertical and horizontal, the vertical occurs five times less frequently. These injuries most often undergo open reduction or, at best, closed reduction under general anesthesia.

Objectives

To remind Emergency Physicians to consider this injury in any patient with severe knee pain and limited mobility, even with a history that is lacking significant trauma.

Case Report

We present a case of intra-condylar patellar dislocation with vertical axis rotation.

Conclusion

This injury is no longer primarily attributed to the young and, barring fracture, closed reduction in the ED should be considered.  相似文献   
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