Silicon nanopillars as a platform for enhanced fluorescence analysis.

The importance of fluorescent detection in many fields is well established. While advancements in instrumentation and the development of brighter fluorophore have increased sensitivity and lowered the detection limits of the method, additional gains can be made by manipulating the local electromagnetic field. Herein we take advantage of silicon nanopillars that exhibit optical resonances and field enhancement on their surfaces and demonstrate their potential in improving performance of biomolecular fluorescent assays.

[The monitoring of application of dabigatran as a remedy of prevention of thromboembolic complications after hip joint arthroplasty].

The analysis was applied to the indicators of hemostasis system under application of new anticoagulant, dabigatran etexilat, after hip joint arthroplasty. It is established that among the coagulation methods analysis the most specific to the effect of dabigatran is the testing of thrombin and echitox time of coagulation. Considering low sensitivity of the echitox to anticoagulation effect of D-dimer the echitox test is optimal for laboratory monitoring of application of dabigatran after orthopedic intervention.

[Pathophysiological features of dorsalgia development among railway workers, connected with railway communication].

Dorsalgia's is an actual medical and social problem. It gains prominent significance among railway workers, connected with railway communication. Pain syndromes among this group of patients have different complex pathogenetic mechanisms of the development.

Silicon nanopillars for field-enhanced surface spectroscopy.

Silicon nanowire and nanopillar structures have drawn increased attention in recent years due in part to their unique optical properties. Herein, electron beam lithography combined with reactive-ion etching is used to reproducibly create individual silicon nanopillars of various sizes, shapes, and heights. Finite difference time domain analysis predicts local field intensity enhancements in the vicinity of appropriately sized and coaxially illuminated silicon nanopillars of approximately 2 orders of magnitude.

[Characteristics of central hemodynamics and cerebrovascular circulation during various anesthesia modes in reconstructive surgeries for the extracranial vessels].

The purpose of the study was to choose an optimal anesthetic method to ensure adequate cerebral blood flow and to reduce the number of perioperative complications during carotid endarterectomy. Total intravenous anesthesia with diprivan, combined cervical plexus block anesthesia, and inhaled sevoflurane anesthesia were assessed in 190 patients undergoing carotid endarterectomy. The study of cerebral blood flow and central hemodynamic parameters indicated that deprivan anesthesia suppressed the major hemodynamic parameters, causing associated cerebral circulation depression.

[Axonopathy in the pathogenesis of multiple sclerosis, peripheral diffuse and local motor neuropathies and motor neuron disease].

Two hundreds and seventy-six patients including 43 patients with multiple sclerosis, 24 - with acute inflammatory demyelinating polyneuropathy (AIDP), 144 - with chronic inflammatory demyelinating polyneuropathy (CIDP), 27 - with motor multifocal neuropathy (MMN), 38 - with lateral amyotrophic sclerosis (LAS) have been examined. Symptoms of axonal degeneration, manifested in denervation phenomena in both clinical and instrumental studies (electromyography, transcranial magnetic stimulation, MRT), were revealed in all groups of patients. The formation of excitation conduction blocks is an universal pathophysiological mechanism of the axonopathy development in AIDP, CIDP, MMN and LAS.

[Differential diagnosis of multifocal motor neuropathy and related diseases].

Multifocal motor neuropathy (MMN) is a rare disease of the peripheral nervous system pathogenetically related to local demyelinization and formation of excitation conduction blocks. MMN affect only those nerves and their segments that comprise excitation conduction blocks. Such blocks have a persistent character and show a mosaic pattern over motor fibres which accounts for the specific clinical picture of MMN.

Subsecond spin relaxation times in quantum dots at zero applied magnetic field due to a strong electron-nuclear interaction.

A key to ultralong electron spin memory in quantum dots (QDs) at zero magnetic field is the polarization of the nuclei, such that the electron spin is stabilized along the average nuclear magnetic field. We demonstrate that spin-polarized electrons in n-doped (In,Ga)As/GaAs QDs align the nuclear field via the hyperfine interaction. A feedback onto the electrons occurs, leading to stabilization of their polarization due to formation of a nuclear spin polaron [I.

[Mechanisms of development of secondary axonal failure in diffuse and local demyelinating neuropathies].

To estimate a qualitative and quantitative effects of axonal failure on the clinical and electromyographic (EMG) picture of diffuse and local demyelination, 24 patients with Guillain-Barre syndrome (GBS), 144 with chronic inflammatory demyelinating polyneuropathy (CIDP) and 27 patients with multifocal motor neuropathy (MMN) have been studied. All the patients underwent a complex clinical neurological and EMG examination. Along with significant association between muscular hypotrophies and weakness in the majority of patients (tau=0,51; p<0,001), in some cases weakness in extremities was found in the absence of amyotrophic syndrome specifying a "functional" axonopathy due to the disturbance of ionic transport and the blockade of potassium channels.

Optical control of spin coherence in singly charged (In,Ga)As/GaAs quantum dots.

Electron spin coherence has been generated optically in n-type modulation doped (In,Ga)As/GaAs quantum dots (QDs) which contain on average a single electron per dot. The coherence arises from resonant excitation of the QDs by circularly polarized laser pulses, creating a coherent superposition of an electron and a trion. Time dependent Faraday rotation is used to probe the spin precession of the optically oriented electrons about a transverse magnetic field.

[Therapeutic effect of dexalgin on disturbances of vertebrogenic and nonvertebrogenic mechanisms in back pain].

To evaluate the effect of Dexalgin on dysregulation mechanisms in the complex therapy of dorsalgia, 39 patients have been studied. They were divided into 2 groups: with vertebrogenic (23 patients) and without vertebrogenic (16 patients) pain syndrome. Dexalgin was prescribed in dosage 75 mg daily during 5 days.

[Renal protective function in surgical treatment for chronic infrarenal aortic aneurysms].

The authors analyzed different modes of prevention of acute renal failure (ARF) in the planned surgical treatment of abdominal aortic aneurysms. A hundred patients randomly divided into 4 groups were examined. In patients from a control group, prevention of renal failure included no use of aminoglycosides, prevention of hyperglycemia, and provision of steady-state hemodynamics.

Optical pumping of the electronic and nuclear spin of single charge-tunable quantum dots.

We present a comprehensive examination of optical pumping of spins in individual GaAs quantum dots as we change the net charge from positive to neutral to negative with a charge-tunable heterostructure. Negative photoluminescence polarization memory is enhanced by optical pumping of ground state electron spins, which we prove with the first measurements of the Hanle effect on an individual quantum dot. We use the Overhauser effect in a high longitudinal magnetic field to demonstrate efficient optical pumping of nuclear spins for all three charge states of the quantum dot.

[A risk of myocardial ischemia and the nature of infusion-transfusion therapy in scheduled surgical treatment of infrarenal aneurisms of the aorta].

The authors analyzed effects produced by different variations of the infusion-transfusion therapy on the risk of cardiovascular complications that can develop in the scheduled surgical treatment of the aorta abdominal part. The patients were randomized in 2 groups. Intraoperative hemodilution was made in group-1 patients (n = 50) before aorta clipping.

Manipulation of the spin memory of electrons in n-GaAs.

We report on the optical manipulation of the electron spin relaxation time in a GaAs-based heterostructure. Experimental and theoretical study shows that the average electron spin relaxes through hyperfine interaction with the lattice nuclei, and that the rate can be controlled by electron-electron interactions. This time has been changed from 300 ns down to 5 ns by variation of the laser frequency.

[Blood loss compensation during surgery of abdominal aortic aneurysms].

Two methods of intraoperative compensation of blood loss in patients with aortic aneurysm are compared in 30 patients: transfusion of donor blood preparations and reinfusion of washed autoerythrocytes. Changes in hemostasis system, central hemodynamics, and oxygen transport were analyzed. Reinfusion of washed autoerythrocytes proved to be more safe and involved no serious complications.

Electron and nuclear spin interactions in the optical spectra of single GaAs quantum dots.

Fine and hyperfine splittings arising from electron, hole, and nuclear spin interactions in the magneto-optical spectra of individual localized excitons are studied. We explain the magnetic field dependence of the energy splitting through competition between Zeeman, exchange, and hyperfine interactions. An unexpectedly small hyperfine contribution to the splitting close to zero applied field is described well by the interplay between fluctuations of the hyperfine field experienced by the nuclear spin and nuclear dipole/dipole interactions.

[Improvement of epidural anesthesia in reconstructive surgery of the aorta in Leriche's syndrome].

Fifty-six patients subjected to aortofemoral bilateral shunting under prolonged epidural anesthesia are examined. Swan-Gans catheter was used to evaluate central and pulmonary hemodynamics. Ganglionic blocking with pentamine for taxiphylaxis was carried out in 31 patients prior to catheterization of the epidural space.

[Treatment of uncomplicated closed fractures of the metatarsal bones by the functional method].

Functional method has been used in the treatment of 110 patients with noncomplicated closed fractures of metatarsal bones. Theoretical rationale of the method is presented. Positive effect of early exercise on the injured limb is demonstrated.

[Comparative assessment of the efficacy of selective and discrete plasmapheresis in combined preoperative preparation of patients with diffuse toxic goiter].

The paper is concerned with comparative assessment of two methods of plasmapheresis (discrete and selective), employed for preoperative preparation of patients with a severe type of thyrotoxicosis. Selective plasmapheresis by its effect on immunity indices, hormonal status, central hemodynamics and clinical symptomatology was shown to be no inferior to the discrete method. At the same time selective plasmapheresis was not accompanied by allergic reactions, excluding the danger of infection and making preoperative preparation cheaper.