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BackgroundThe continuous recurrences of condylomata acuminata makes it necessary to constantly search for therapeutic alternatives.Patients and methodTo evaluate the therapeutic efficacy and safety of pegylated interferon (IFN p) adjuvant to cryosurgery, an open clinical trial was conducted in condylomata acuminata in 30 patients from the «Hermanos Ameijeiras» hospital, who were randomized to receive 6 weeks (group I) subcutaneous recombinant human interferon alfa 2b (IFN), 3 times per week + biweekly cryosurgery or (group II) subcutaneous IFN p, 1 time per week + biweekly cryosurgery. The main variable was the percentage of recurrence at one year of follow-up. There was also a rigorous control of adverse events.ResultsAt the end of the treatment 12/15 (80%) patients in group I and group II 14/15 (93,3%) were without injuries (p < 0.32). During follow-up, none of the patients who received IFN p + cryosurgery had recurrences; while 2/12 (16.7%) of the patients who received IFN + cryosurgery recurred (p < 0.672). Adverse events were significantly more frequent in group I (fever 13/15, headache 7/15, chills 3/15, and myalgia 2/15) (p < 0.003).ConclusionPegylated interferon with a weekly frequency of administration achieves superior therapeutic effects, a lower percentage of recurrences and adverse reactions than the administration of recombinant human IFN alpha 2b 3 times a week.  相似文献   
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Heart Failure Reviews - Cardiac resynchronization therapy (CRT) may improve not only impaired left ventricular contractility but can also induce reverse remodeling of native conduction system....  相似文献   
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The presence of pesticides has recently been reported in shrimp farms adjacent to agricultural areas on the east coast of the Gulf of California. This study assessed the possible effect of organophosphorus pesticides in the coastal environment of Sinaloa, México, using the white shrimp Litopenaeus vannamei as a bioindicator since their presence, abundance or behavior indicate some process or state of the system in which they live. Sublethal bioassays were performed on shrimps in intermolt state using commercial brands of organophosphorus pesticides, chlorpyrifos (0.0015 mg l−1), diazinon (0.0120 mg l−1), methamidophos (1.207 mg l−1), azinphos-methyl (0.0101 mg l−1), and methyl parathion (0.0075 mg l−1) were tested. Results showed reductions in glycogen, triglycerides, and total protein concentrations in shrimp muscle, except for the diazinon treatments, in which an increase in triglyceride level was detected. The observed alterations in the three cellular components were probably due to the metabolic compensation mechanism of the shrimp in reaction to the stress produced by organophosphorus pesticides, which act as endocrine disruptors. The establishment of continuous environmental monitoring programs of the coastal zone of Northwestern Mexico is strongly recommended.

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Purpose: Pelvic fracture evaluation with abdominopelvic computed tomography (CT) and formal CT cystography for rule out of urine bladder injury have been commonly employed in pediatric trauma patients. The additional delayed imaging required to obtain optimal CT cystography is, however, associated with increased doses of ionizing radiation to pelvic organs and represent a significant risk in the pediatric population for future carcinogenic risk. We hypothesized that avoidance of routine CT cystography among pediatric pelvic fracture victims would not result in an appreciable rate of missed bladder injuries and would aid in mitigating the radiation exposure risk associated with these additional images. Methods: A retrospective cohort study involving blunt trauma pelvic fractures among pediatric trauma patients (age<14) between the years 1997 and 2016 was conducted utilizing the Israeli National Trauma Registry. Statistical analysis was performed using SAS statistical software version 9.4 via the tests of Chisquare test and two-sided Fisher''s exact test. A p value of less than 0.05 was considered statistically significant. Results: A total of 1072 children were identified from the registry for inclusion. Mean age of patients was 7.7 years (range 0-14) and 713 (66.5%) were male. Overall mortality in this population was 4.1% (44/1072). Only 2.1% (23) of pediatric patients with pelvic fractures had bladder injury identified, with just 9 children having intraperitoneal bladder rupture (0.8% of all the patients). Conclusion: The vast majority of blunt pediatric trauma victims with pelvic fractures do not have urine bladder injuries. Based on our study results we do not recommend the routine utilization of CT cystography in this unique population.  相似文献   
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Anxiety sensitivity is a potential risk factor for posttraumatic stress symptoms (PTSS) and has been hypothesized to contribute to PTSS development. However, few prospective studies have evaluated whether anxiety sensitivity predicts PTSS. In a subsample of 48 women sexual assault survivors enrolled as part of a larger prospective observational study, elevated anxiety sensitivity measured via a brief assessment 1 week after experiencing a sexual assault was concurrently associated with PTSS at 1 week and prospectively predicted PTSS 6 weeks after the event, with small-to-medium effect sizes, η2p = .10, even after covarying for trauma history. Heightened anxiety sensitivity at 1-week postevent also interacted with time to predict anxiety and depression both before and after sexual assault, with medium-to-large effect sizes, ηp2 = .21– .24. This is consistent with research linking anxiety sensitivity to PTSS, but this was the first prospective study of which we are aware to demonstrate that anxiety sensitivity in the acute posttrauma period predicts PTSS among women who have recently experienced sexual assault. Future research should use the full Anxiety Sensitivity Index to replicate findings in a larger sample and explore whether targeting anxiety sensitivity could mitigate the development of PTSS in this vulnerable population.  相似文献   
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Since the discovery of spin glasses in dilute magnetic systems, their study has been largely focused on understanding randomness and defects as the driving mechanism. The same paradigm has also been applied to explain glassy states found in dense frustrated systems. Recently, however, it has been theoretically suggested that different mechanisms, such as quantum fluctuations and topological features, may induce glassy states in defect-free spin systems, far from the conventional dilute limit. Here we report experimental evidence for existence of a glassy state, which we call a spin jam, in the vicinity of the clean limit of a frustrated magnet, which is insensitive to a low concentration of defects. We have studied the effect of impurities on SrCr9pGa12-9pO19 [SCGO(p)], a highly frustrated magnet, in which the magnetic Cr3+ (s = 3/2) ions form a quasi-2D triangular system of bipyramids. Our experimental data show that as the nonmagnetic Ga3+ impurity concentration is changed, there are two distinct phases of glassiness: an exotic glassy state, which we call a spin jam, for the high magnetic concentration region (p > 0.8) and a cluster spin glass for lower magnetic concentration (p < 0.8). This observation indicates that a spin jam is a unique vantage point from which the class of glassy states of dense frustrated magnets can be understood.Understanding glassy states found in dense frustrated magnets has been an intellectual challenge since peculiar low-temperature glassy behaviors were observed experimentally in the quasi-2D SrCr9pGa12-9pO19 (SCGO) (13) and in the 3D pyrochlore Y2Mo2O7 (4). Immediately following, theoretical investigations (59) were performed to see if an intrinsic spin freezing transition is possible in a defect-free situation, aided by quantum fluctuations, as in the order-by-fluctuations phenomenon (10, 11). Quantum fluctuations at T = 0 were shown to select a long-range ordered state in the 2D kagome isotropic antiferromagnet (AFM) (5, 6), later expanded to the isotropic pyroclore and SCGO (9). Anisotropic interactions were also considered as a possible origin of the glassy kagome AFM (7). For an XY pyrochlore AFM, thermal fluctuations were found to induce a conventional Neel order (8). Experimental works were also performed to investigate if the glassy states are extrinsic due to site defects or random couplings or intrinsic to the magnetic lattice (12, 13). The consensus is that the low-temperature spin freezing transitions in SCGO(p) near the clean limit (p ≈ 1) is not driven by site defects (13).The nature of the frozen state in SCGO has been investigated by numerous experimental techniques, including bulk susceptibility (13), specific heat (2, 14), muon spin relaxation (μSR) (15), nuclear magnetic resonance (NMR) (13, 16), and elastic and inelastic neutron scattering (17). Observed are spin glassy behaviors, such as field-cooled and zero-field-cooled (FC/ZFC) hysteresis in bulk susceptibility (3), as well as non-spin-glassy behaviors, such as a quadratic behavior of specific heat at low T, Cv ∝ T2 (14), linear dependence of the imaginary part of the dynamic susceptibility at low energies, χ″(ω) ∝ ω (17), and a broad but prominent momentum dependence of the elastic neutron scattering intensity (17). The interpretation of the frozen state below Tf is still controversial. One possibility suggested was a spin liquid with unconfined spinons or resonating valence bond state, based on NMR and μSR studies (15, 16). Many-body singlet excitations were also suggested to be responsible for the Cv ∝ T2 behavior (14).Recently, some of us presented an alternative scenario involving a spin jam state by considering the effects of quantum fluctuations in the disorder-free quasi-2D ideal SCGO lattice with a simple nearest neighbor (NN) spin interaction Hamiltonian ? = JNNSi ? Sj (18, 19). The spin jam framework provided a qualitatively coherent understanding of all of the low-temperature behaviors such as that a complex energy landscape is responsible for the frozen state without long-range order (18), and Halperin−Saslow (HS)-like modes for the Cv ∝ T2 and χ″(ω) ∝ ω behaviors (5, 18). In this system, which we refer to as the ideal SCGO model (iSCGO), semiclassical magnetic moments (or spins) are arranged in a triangular network of bipyramids and interact uniformly with their NN (18, 19). The microscopic mechanism for the spin jam state is purely quantum mechanical. The system has a continuous and flat manifold of ground states at the mean field level, including locally collinear, coplanar, and noncoplanar spin arrangements. Quantum fluctuations lift the classical ground state degeneracy (order by fluctuations), resulting in a complex rugged energy landscape that has a plethora of local minima consisting of the locally collinear states separated from each other by potential barriers (18). Although the work of ref. 18 dealt with a similar phase space constriction by quantum fluctuations as the aforementioned other theoretical works did, we would like to stress here the difference between the two: Whereas the other works mainly focused on the selection of the long-range-ordered (LRO) energetic ground state, the work of ref. 18 showed that the short-range-ordered (SRO) states that exist at higher energies are long-lived, dominate entropically over the LRO states, and govern the low-T physics.The introduction of nonmagnetic impurities into a topological spin jam state breaks some of the constraints in the system, and possibly allows local transitions between minima, with a time scale dependent on the density of impurities. At a sufficiently high vacancy concentration, the system exits the spin jam state and becomes either paramagnetic or an ordinary spin glass at lower temperatures. Here we try to identify and explore the spin jam regime in an experimentally accessible system. The three most important signatures we seek for the existence of a spin jam state, different from conventional spin glass states, are (i) a linear dependence of the imaginary part of the dynamic susceptibility at low energies, χ″(ω) ∝ ω, (ii) intrinsic short range static spin correlations, and (iii) insensitivity of its physics to nonmagnetic doping near the clean limit. In the rest of the paper, we provide experimental demonstration of these properties.Experimentally, there are, so far, two materials, SrCr9pGa12-9pO19 [SCGO(p)] (13, 1317, 20) and qs-ferrites like Ba2Sn2ZnGa3Cr7O22 (BSZGCO) (21), in which the magnetic Cr3+ (3d3) ion surrounded by six oxygen octahedrally, form distorted quasi-2D triangular lattice of bipyramids (20, 21) as shown in Fig. 1A, and thus may realize a spin jam state. We would like to emphasize that these systems are very good insulators (resistivity ρ > ?1013?Ω ? cm at 300 K) and the Cr3+ (t2g3) ion has no orbital degree of freedom. Furthermore, the neighboring Cr ions share one edge of oxygen octahedral, and thus the direct overlap of the t2g3 orbitals of the neighboring Cr3+ ions make the AFM NN Heisenberg exchange interactions dominant and further neighbor interactions negligible (22, 23), as found in Cr2O3 (24) and ZnCr2O4 (25).Open in a separate windowFig. 1.(A) In SrCr9pGa12-9pO19 [SCGO(p)], the magnetic Cr3+ (3d3, s = 3/2) ions form the kagome−triangular−kagome trilayer (Top). The blue and red spheres represent kagome and triangular sites, respectively. When viewed from the top of the layers, they form the triangular network of bipyramids (Bottom). (B) The pT phase diagram of SCGO(p) constructed by bulk susceptibility and elastic neutron scattering measurements on powder samples with various p values. The freezing temperatures, Tf, marked with blue square and black circle symbols are obtained by bulk susceptibility and elastic neutron scattering measurements, respectively. Note that the values of Tf are much lower than the Curie–Weiss temperatures (see Fig. S1). Filled blue squares represent the data obtained from samples whose crystal structural parameters including the Cr/Ga concentrations were refined by neutron diffraction measurements (see Fig. S2 and Tables S1S4), and open blue squares represent samples with nominal p values. For nominal p = 0.2, no freezing was observed down to 50 mK (see Fig. S3).  相似文献   
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We perform rapid spontaneous Raman 2D imaging in light-sheet microscopy using continuous wave lasers and interferometric tunable filters. By angularly tuning the filter, the cut-on/off edge transitions are scanned along the excited Stokes wavelengths. This allows obtaining cumulative intensity profiles of the scanned vibrational bands, which are recorded on image stacks; resembling a spectral version of the knife-edge technique to measure intensity profiles. A further differentiation of the stack retrieves the Raman spectra at each pixel of the image which inherits the 3D resolution of the host light sheet system. We demonstrate this technique using solvent solutions and composites of polystyrene beads and lipid droplets immersed in agar and by imaging the C–H (2800-3100cm−1) region in a C. elegans worm. The image acquisition time results in 4 orders of magnitude faster than confocal point scanning Raman systems, allowing the possibility of performing fast spontaneous Raman·3D-imaging on biological samples.OCIS codes: (170.3880) Medical and biological imaging, (180.5655) Raman microscopy, (300.6450) Spectroscopy, Raman, (110.4234) Multispectral and hyperspectral imaging  相似文献   
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