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101.
We made clinical trials of en bloc extended radical mastectomy (EXT) of a new type in 118 patients from 1980 through 1985. Conventional radical mastectomies (RDL) were also performed in 105 patients from 1973 through 1985. A multivariate analysis was performed to compare the results of EXT and RDL. As the result, the 5-year survival rates of 91 +/- 2.6% and 83 +/- 3.7% were achieved for the EXT and RDL groups, respectively (Cox P value for comparison of survival curves = 0.16). Adjusted Cox regression analysis revealed a significantly favorable result of EXT (P = 0.03). This difference was most remarkable in patients with one to three metastatic axillary lymph nodes, although it was not statistically significant because of too small number of patients available (P = 0.18). The results are thus not definite, but suggest that EXT may be advantageous over RDL especially in patients with a few metastatic axillary lymph nodes.  相似文献   
102.
The management of cervical lymph node metastases in well-differentiated carcinoma of the thyroid is controversial. In our department, from 1963 to 1972, node plucking was performed only in patients with cervical lymphadenopathy whereas, from 1973 to 1983, modified radical neck dissection was therapeutically or electively performed. In order to determine whether the more extensive dissection is adequate, a retrospective analysis was performed using two groups of patients who were managed differently with regard to the treatment of cervical lymph node metastases. From this series of 206 patients with more than five years follow-up, it was found that the rates of survival and lymph node recurrence did not differ between the two groups. However, since the well-differentiated carcinoma of the thyroid has relatively indolent biological behaviour, further long-term follow-up seems to be necessary for demonstrating the efficacy of neck dissection.  相似文献   
103.
104.

Purpose

The purpose of this work is to explore audiometry following cochlear implantation (CI) in patients with enlarged vestibular aqueduct (EVA) and to investigate the effects of inner ear morphological variation on post CI audiometry.

Methods

This was a retrospective review of both natural and cochlear-implant-aided audiometry results, using all available measurements in a mixed-effects model accounting for longitudinal change and the grouping structure of ears. Patients who visited our tertiary academic medical center between 2000 and 2016 were identified as having EVA according to Cincinnati criteria on radiological examination; patients eligible for CI were then selected for analysis.

Results

Multivariable modeling showed a statistically significant hearing improvement in ears with EVA undergoing CI with regards to pure tone average (?64.0?dB, p?<?0.0001), speech reception threshold (?57.90?dB, p?<?0.0001), and word score (34.8%, p?>?0.0001). Vestibular aqueduct midpoint size and the presence of incomplete partition type II (IP II) did not have significant independent associations with audiometric findings. However, multivariable modeling revealed a statistically significant interaction between IP II and CI such that IP II ears demonstrated a decrease in WS improvement of 30.2% (p?=?0.0059) compared to non-IP II ears receiving CI.

Conclusion

There is a statistically significant audiometric benefit to ears with EVA receiving CI. Morphology, specifically the presence of IP II, may hinder CI benefit in terms of word score however this finding needs clinical validation. This data improves personalization of surgical counseling and planning for patients with EVA considering CI.  相似文献   
105.
Phylogenetic analysis of influenza viruses collected during December 2009–February 2010 from chickens in live poultry retail shops in Lahore, Pakistan, showed influenza A(H9N2) lineage polymerase and nonstructural genes generate through inter- and intrasubtypic reassortments. Many amino acid signatures observed were characteristic of human isolates; hence, their circulation could enhance inter- or intrasubtypic reassortment.  相似文献   
106.
107.
This work evaluates the antifungal activity of two essential oil components against 28 clinical isolates (17 sensitive, 11 resistant) and 3 standard laboratory strains of Candida. Growth of the organisms was significantly effected in both solid and liquid media at different test compound concentrations. The minimum inhibitory concentrations (MICs) of Isoeugenol (compound 1) against 31 strains of Candida ranged 100–250 μg/ml and those of o ‐methoxy cinnamaldehyde (compound 2) ranged 200–500 μg/ml, respectively. Insight studies to mechanism suggested that these compounds exert antifungal activity by targeting H+‐ATPase located in the membranes of pathogenic Candida species. At their respective MIC90 average inhibition of H+‐efflux for standard, clinical and resistant isolates caused by compound 1 and compound 2 was 70%, 74%, 82% and 42%, 42% and 43%. Respective inhibition of H+‐efflux by fluconazole (5 μg/ml) was 94%, 92% and 10%. Inhibition of H+‐ATPase leads to intracellular acidification and cell death. SEM analysis of Candida cells showed cell membrane breakage and alterations in morphology. Haemolytic activity on human erythrocytes was studied to exclude the possibility of further associated cytotoxicity. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
108.
Poly(caprolactone) (PCL) has been frequently considered for bone tissue engineering because of its excellent biocompatibility. A drawback, however, of PCL is its inadequate mechanical strength for bone tissue engineering and its inadequate bioactivity to promote bone tissue regeneration from mesenchymal stem cells. To correct this deficiency, this work investigates the addition of nanoparticles of silica (nSiO(2)) to the scaffold to take advantage of the known bioactivity of silica as an osteogenic material and also to improve the mechanical properties through nanoscale reinforcement of the PCL fibers. The nanocomposite scaffolds and the pristine PCL scaffolds were evaluated physicochemically, mechanically, and biologically in the presence of human mesenchymal stem cells (hMSCs). The results indicated that, when the nanoparticles of size approximately 10?nm (concentrations of 0.5% and 1% w/v) were embedded within, or attached to, the PCL nanofibers, there was a substantial increase in scaffold strength, protein adsorption, and osteogenic differentiation of hMSCs. These nSiO(2) nanoparticles, when directly added to the cells evidently pointed to ingestion of these particles by the cells followed by cell death. The polymer nanofibers appeared to protect the cells by preventing ingestion of the silica nanoparticles, while at the same time adequately exposing them on fiber surfaces for their desired bioactivity.  相似文献   
109.
Human immunodeficiency virus (HIV) infection is a major health burden across the world which leads to the development of acquired immune deficiency syndrome (AIDS). This review article discusses the prevalence of HIV, its major routes of transmission, natural immunity, and evasion from the host immune system. HIV is mostly prevalent in Sub‐Saharan Africa and low income countries. It is mostly transmitted by sharing syringe needles, blood transfusion, and sexual routes. The host immune system is categorized into three main types; the innate, the adaptive, and the intrinsic immune system. Regarding the innate immune system against HIV, the key players are mucosal membrane, dendritic cells (DCs), complement system, interferon, and host Micro RNAs. The major components of the adaptive immune system exploited by HIV are T cells mainly CD4+ T cells and B cells. The intrinsic immune system confronted by HIV involves (apolipoprotein B mRNA‐editing enzyme, catalytic polypeptide‐like 3G) APOBEC3G, tripartite motif 5‐α (TRIM5a), terherin, and (SAM‐domain HD‐domain containing protein) SAMHD1. HIV‐1 efficiently interacts with the host immune system, exploits the host machinery, successfully replicates and transmits from one cell to another. Further research is required to explore evasion strategies of HIV to develop novel therapeutic approaches against HIV.  相似文献   
110.
The study was designed to evaluate the role of antioxidant defense system in the etiology of psoriasis, a chronic skin disorder of complex etiology and pathology. Hospital-based case–control study was carried out in major referral hospital in Kashmir, North India. Cases (N?=?40) were composed of patients with psoriasis vulgaris, and controls (N?=?20) were healthy volunteers. Study included estimation in plasma of both patients and controls of glutathione (GSH) levels, superoxide dismutase (SOD) activity, and total antioxidant potential (AOP) as indices of antioxidant defense system and malondialdehyde (MDA) as a measure of lipid peroxidation (LP), an indicator of oxidative stress. The GSH levels, SOD activity, AOP, and malondialdehyde levels in plasma of psoriasis patients were 2.58?±?0.22 μM/l, 5.24?±?0.69 U/ml, 0.020?±?.011?nmol?1/ml?h, and 0.88?±?0.20 nmol/ml and were 4.76?±?0.52 μM/l, 4.14?±?0.56U/ml, 0.042?±?0.018 nmol?1/ml?h, and 0.53?±?0.16 nmol/ml in healthy voluntary controls, respectively. A significant decrease in GSH levels (p?<?0.005) and AOP (p?<?0.005) and significant increase in SOD activity (p?<?0.01) MDA levels (p?<?0.005) as an indicator of LP was observed.  相似文献   
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