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61.
62.
Pavel E. Kazin Mikhail A. Zykin Lev A. Trusov Alexander V. Vasiliev Reinhard K. Kremer Robert E. Dinnebier Martin Jansen 《RSC advances》2020,10(62):37588
Dy–Mg silicate Dy8Mg2(SiO4)6O2 has been prepared by high-temperature solid state reaction. It has an apatite type structure (P63/m) with the Dy atoms fully occupying the 6h site and being in random distribution with the Mg atoms at the 4f site. The compound reveals dual magnetization relaxation with widely varying contributions from fast (FR) and slow (SR) relaxation paths controlled by field and temperature. The SR path is stabilized by a strong magnetic field, exhibits a weak dependence of relaxation time τ on field and temperature, and sustains large τ of a few seconds up to a temperature of 40 K and under a field of 50 kOe. The analysis of the electronic structure and comparison with the known Dy-doped phosphate apatites suggests that the Orbach and Raman processes are suppressed.The compound reveals dual magnetization relaxation with largely varying contributions from fast and slow relaxation paths controlled by field and temperature. The relaxation times retain values of a few seconds up to 40 K. 相似文献
63.
64.
Lisovsky M Patel K Cymes K Chase D Bhuiya T Morgenstern N 《Archives of pathology & laboratory medicine》2007,131(8):1304-1311
Anal gland carcinoma (AGC) is a rare perianal invasive cancer composed of tubular glands lined by cuboidal epithelium. The clinical features and histogenesis of AGC are not well understood and its origin from anal glands is often difficult to prove. Little is known about immunophenotypic features of AGC that could be useful in establishing the diagnosis. This study evaluated the immunohistochemical profile of 2 cases of AGC in comparison to anal glands from 11 hemorrhoidectomy specimens. Sections from the specimens were routinely processed and immunostained using commercial antibodies to cytokeratin (CK) 7, CK20, CK5/ 6, p63, CDX2, smooth muscle actin, calponin, heavy chain smooth muscle myosin, p53, and p16. In case 1 of AGC, radiation and chemotherapy preceded an abdominoperineal resection. In biopsies from this case, the neoplastic anal glands had a tubular pattern, whereas most glands in the resection specimen exhibited mucinous features. The histologic pattern in case 2 was tubular. Normal anal glands showed immunoreactivity for myoepithelial and basal cell markers CK5/6 and p63 in basal and parabasal cell layers and for CK7 in superficial cell layers. In contrast, both cases of AGC were negative for CK5/6 and p63 and were diffusely positive for CK7. Normal glands and both cases of AGC were negative for the intestinal differentiation marker CDX2, CK20, smooth muscle actin, calponin, smooth muscle myosin heavy chain, p16, and p53. Our data suggest that loss of p63 and CK5/6 expression is a feature of AGC. Anal gland carcinoma shares negativity for CDX2 and CK7+/CK20- profile with normal anal glands. No evidence of myoepithelial cells was found in normal or malignant anal glands. These data may be useful in establishing the diagnosis of AGC. 相似文献
65.
Xiang Y John P Yakushin SB Kunin M Raphan T Cohen B 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,177(4):551-572
We characterized the three-dimensional kinematics and dynamics of quadrupedal gait of young adult rhesus and cynomolgus monkeys
while they walked with diagonal and lateral gaits at 0.4–1.0 m/s on a treadmill. Rigid bodies on the wrist, ankle, and back
were monitored by an optical motion detection system (Optotrak). Kinematic data could be normalized using characteristic stride
length, reducing variance due to different gait styles, to emphasize common characteristics of swing and stance parameters
among animals. Mean swing phase durations fell as walking speed increased, but the swing phase durations increased at each
walking velocity as a linear function of increases in amplitude, thereby following a main sequence relationship. The phase
plane trajectories of the swing phases, i.e., plots of the relation of the rising and falling limb velocity to limb position
in the sagittal (X–Z) plane, had unique dynamic characteristics. Trajectories were separable at each walking velocity and increases in swing amplitude
were linearly related to peak swing velocities, thus comprising main sequences. We infer that the swing phase dynamics are
set by central neural mechanisms at the onset of the swing phases according to the intended amplitude, which in turn is based
on the walking velocity in the stance phases. From the many dynamic similarities between swing phases and rapid eye movements,
we further suggest that the swing phases may be generated by neural mechanisms similar to those that produce saccades and
quick phases of nystagmus from a signal related to sensed or desired walking velocity.
Grants: This work was supported by National Institute of Health Grants EY11812, EY04148, DC05204, and EY01867. 相似文献
66.
Andrey Morozov Mark Taratkin Eric Barret Nirmish Singla Evgeniy Bezrukov Denis Chinenov Mikhail Enikeev Juan Gomez Rivas Anastasia Shpikina Dmitry Enikeev 《Andrologia》2020,52(10):e13789
Irreversible electroporation is a treatment option used for focal therapy. In this systematic review, we summarise data on irreversible electroporation outcomes in patients with localised prostate cancer. We performed a literature search in 3 databases and included articles with own data on irreversible electroporation results in patients with localised prostate cancer. Primary outcome was procedure efficacy measured as the absence of cancer in the treatment area on the follow-up biopsy. Secondary outcomes were the absence of prostate cancer recurrence in the treatment area on MRI, out-of-field recurrence, complications and functional outcomes (erectile function and micturition). In-field recurrence rate was 0%–39% and out-field 6.4%–24%. In all studies, PSA level decreased: twice lower than baseline after 4 weeks and by 76% after 2 years. Most of the authors noted sexual and urinary toxicity during the first half year after surgery. However, functional outcomes recovered to baseline after 6 months with mild decrease in sexual function. Complication rates after irreversible electroporation were 0%–1% of Clavien–Dindo III and 5%–20% of Clavien–Dindo I–II. Irreversible electroporation has promise oncological outcomes, rate of post-operative complications and minimal-to-no effects on erectile and urinary function. However, medium and long-term data on cancer-specific and recurrence-free survival are still lacking. 相似文献
67.
Antaki Fares Coussa Razek Georges Mikhail Mikel Archambault Cyril Lederer David E. 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(12):2681-2690
Graefe's Archive for Clinical and Experimental Ophthalmology - To investigate the prognostic value of peripheral retinal nonperfusion in patients with diabetic retinopathy using ultra-widefield... 相似文献
68.
David Goerlitz Sania Amr Chiranjeev Dash Doa'a A. Saleh Mai El Daly Mohamed Abdel-Hamid Sherif El Kafrawy Tamer Hifnawy Sameera Ezzat Mohamed A. Abdel-Aziz Hussein Khaled Yun-Ling Zheng Nabiel Mikhail Christopher A. Loffredo 《Urologic oncology》2014,32(1):47.e15-47.e20
BackgroundBladder cancer is the most prevalent form of cancer in men among Egyptians, for whom tobacco smoke exposure and Schistosoma haematobium (SH) infection are the major risk factors. We hypothesized that functional polymorphisms in NAD(P)H:quinone oxidoreductase 1 (NQO1) and superoxide dismutase 2 (SOD2), modulators of the effects of reactive oxidative species, can influence an individual's susceptibility to these carcinogenic exposures and hence the risk of bladder cancer.MethodsWe assessed the effects of potential interactions between functional polymorphisms in the NQO1 and SOD2 genes and exposure to smoking and SH infection on bladder cancer risk among 902 cases and 804 population-based controls in Egypt. We used unconditional logistic regression to estimate the odds ratios (OR) and confidence intervals (CI) 95%.ResultsWater pipe and cigarette smoking were more strongly associated with cancer risk among individuals with the TT genotype for SOD2 (OR [CI 95%] = 4.41 [1.86–10.42]) as compared with those with the CC genotype (OR [CI 95%] = 2.26 [0.97–6.74]). Conversely, the risk associated with SH infection was higher among the latter (OR [CI 95%] = 3.59 [2.21–5.84]) than among the former (OR [CI 95%] = 1.86 [1.33–2.60]). Polymorphisms in NQO1 genotype showed a similar pattern, but to a much lesser extent. The highest odds for having bladder cancer following SH infection were observed among individuals with the CC genotypes for both NQO1 and SOD2 (OR [CI 95%] = 4.41 [2.32–8.38]).ConclusionOur findings suggest that genetic polymorphisms in NQO1 and SOD2 play important roles in the etiology of bladder cancer by modulating the effects of known contributing factors such as smoking and SH infection. 相似文献
69.
Lara S. Hwa Mikhail Kalinichev Hasnaà Haddouk Sonia Poli Klaus A. Miczek 《Psychopharmacology》2014,231(2):333-343
Rationale
A promising pharmacotherapy for alcohol use disorders has been positive allosteric modulators (PAMs) of the γ-aminobutyric acid receptor B (GABAB R) since GABAB R PAMs reduce ethanol drinking and self-administration in rodents.Objective
The current studies investigated a novel, selective GABAB R PAM, ADX71441, in comparison to naltrexone in a protocol of ethanol binge-like drinking, drinking-in-the-dark (DID), and in a model of long-term, excessive drinking, intermittent access to ethanol (IA).Methods
Male C57BL/6 J mice were given doses of ADX71441 (3, 10, 30 mg/kg, p.o.) before the fourth test day of repeated DID access to 20 % ethanol. Another group of mice had a history of 4 weeks of IA before ADX71441 (3, 10, 17 mg/kg, p.o.) treatment. The opioid antagonist, naltrexone (0.1, 1, 10 mg/kg, i.p.), was administered to different groups of mice in both protocols as a positive control.Results
In both DID and IA protocols, ADX71441 showed a selective and potent reduction of ethanol drinking, but not water drinking, while naltrexone had a more modest and transient effect on reducing ethanol drinking. The long-lasting effect of ADX71441 agrees with its plasma pharmacokinetics in showing peak concentrations at 2 h followed by a slow decay lasting well beyond 8 h.Conclusions
These findings support previous studies demonstrating that GABAB R PAMs decrease voluntary ethanol intake without altering water intake. ADX71441 may be a worthwhile candidate for developing a treatment of alcoholism, yet its site of action in the brain and long-term pharmacological effects require further exploration. 相似文献70.
Sergei V. Raik Tatiana V. Mashel Albert R. Muslimov Olga S. Epifanovskaya Mikhail A. Trofimov Daria N. Poshina Kirill V. Lepik Yury A. Skorik 《Materials》2021,14(9)
Polyplex-based gene delivery systems are promising substitutes for viral vectors because of their high versatility and lack of disadvantages commonly encountered with viruses. In this work, we studied the DNA polyplexes with N-[4-(N,N,N-trimethylammonium)benzyl]chitosan chloride (TMAB-CS) of various compositions in different cell types. Investigations of the interaction of TMAB-CS with DNA by different physical methods revealed that the molecular weight and the degree of substitution do not dramatically influence the hydrodynamic properties of polyplexes. Highly substituted TMAB-CS samples had a high affinity for DNA. The transfection protocol was optimized in HEK293T cells and achieved the highest efficiency of 30–35%. TMAB-CS was dramatically less effective in nonadherent K562 cells (around 1% transfected cells), but it was more effective and less toxic than polyarginine. 相似文献