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BACKGROUND: Ultrasound may be useful to identify the spinal anesthesia insertion point, particularly when landmarks are not palpable. We tested the hypothesis that the number of needle redirections/re-insertions is lower when using a handheld ultrasound device compared with palpation in obese women undergoing spinal anesthesia for cesarean delivery. METHODS: Study recruits were obese (body mass index (BMI) >30â¯kg/m2) women with impalpable bony landmarks who were undergoing spinal anesthesia for elective cesarean delivery. Women were randomized to ultrasound or palpation. The primary study outcome was a composite between-group comparison of total number of needle redirections (any withdrawal and re-advancement of the needle and/or introducer within the intervertebral space) or re-insertions (any new skin puncture in the same or different intervertebral space) per patient. Secondary outcomes included insertion site identification time and patient verbal numerical pain score (0-10) for comfort during surgical skin incision. RESULTS: Forty women completed the study. The mean BMI (standard deviation) for the ultrasound group was 39.8 (5.5) kg/m2 and for the palpation group 37.3 (5.2) kg/m2. There was no difference in the composite primary outcome (median (interquartile range) [range]) between the ultrasound group (4 (2-13) [2-22]) and the palpation group (6 (4-10) [1-17]) (P=0.22), with the 95% confidence interval of the difference 2 (-1.7 to 5.7). There were no differences in the secondary outcomes. CONCLUSIONS: Handheld ultrasound did not demonstrate any advantages over traditional palpation techniques for spinal anesthesia in an obese population undergoing cesarean delivery, although the study was underpowered to show a difference.
Assuntos
Raquianestesia , Raquianestesia/métodos , Cesárea/métodos , Feminino , Humanos , Obesidade/complicações , Palpação/métodos , Gravidez , Ultrassonografia de Intervenção/métodosRESUMO
A series of thin glass-shell shock-driven DT gas-filled capsule implosions was conducted at the OMEGA laser facility. These experiments generate conditions relevant to the central plasma during the shock-convergence phase of ablatively driven inertial confinement fusion (ICF) implosions. The spectral temperatures inferred from the DTn and DDn spectra are most consistent with a two-ion-temperature plasma, where the initial apparent temperature ratio, T_{T}/T_{D}, is 1.5. This is an experimental confirmation of the long-standing conjecture that plasma shocks couple energy directly proportional to the species mass in multi-ion plasmas. The apparent temperature ratio trend with equilibration time matches expected thermal equilibration described by hydrodynamic theory. This indicates that deuterium and tritium ions have different energy distributions for the time period surrounding shock convergence in ignition-relevant ICF implosions.
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Fuel-ion species dynamics in hydrodynamiclike shock-driven DT^{3}He-filled inertial confinement fusion implosion is quantitatively assessed for the first time using simultaneously measured D^{3}He and DT reaction histories. These reaction histories are measured with the particle x-ray temporal diagnostic, which captures the relative timing between different nuclear burns with unprecedented precision (â¼10 ps). The observed 50±10 ps earlier D^{3}He reaction history timing (relative to DT) cannot be explained by average-ion hydrodynamic simulations and is attributed to fuel-ion species separation between the D, T, and ^{3}He ions during shock convergence and rebound. At the onset of the shock burn, inferred ^{3}He/T fuel ratio in the burn region using the measured reaction histories is much higher as compared to the initial gas-filled ratio. As T and ^{3}He have the same mass but different charge, these results indicate that the charge-to-mass ratio plays an important role in driving fuel-ion species separation during strong shock propagation even for these hydrodynamiclike plasmas.
RESUMO
The structure of a strong collisional shock front forming in a plasma is directly probed for the first time in laser-driven gas-jet experiments. Thomson scattering of a 526.5 nm probe beam was used to diagnose temperature and ion velocity distribution in a strong shock (Mâ¼11) propagating through a low-density (ρâ¼0.01 mg/cc) plasma composed of hydrogen. A forward-streaming population of ions traveling in excess of the shock velocity was observed to heat and slow down on an unmoving, unshocked population of cold protons, until ultimately the populations merge and begin to thermalize. Instabilities are observed during the merging, indicating a uniquely plasma-phase process in shock front formation.
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We present narrow-band self-emission x-ray images from a titanium tracer layer placed at the fuel-shell interface in 60-laser-beam implosion experiments at the OMEGA facility. The images are acquired during deceleration with inferred convergences of â¼9-14. Novel here is that a systematically observed asymmetry of the emission is linked, using full sphere 3D implosion modeling, to performance-limiting low mode asymmetry of the drive.
RESUMO
Anomalous reduction of the fusion yields by 50% and anomalous scaling of the burn-averaged ion temperatures with the ion-species fraction has been observed for the first time in D^{3}He-filled shock-driven inertial confinement fusion implosions. Two ion kinetic mechanisms are used to explain the anomalous observations: thermal decoupling of the D and ^{3}He populations and diffusive species separation. The observed insensitivity of ion temperature to a varying deuterium fraction is shown to be a signature of ion thermal decoupling in shock-heated plasmas. The burn-averaged deuterium fraction calculated from the experimental data demonstrates a reduction in the average core deuterium density, as predicted by simulations that use a diffusion model. Accounting for each of these effects in simulations reproduces the observed yield trends.
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Clear evidence of the transition from hydrodynamiclike to strongly kinetic shock-driven implosions is, for the first time, revealed and quantitatively assessed. Implosions with a range of initial equimolar D3He gas densities show that as the density is decreased, hydrodynamic simulations strongly diverge from and increasingly overpredict the observed nuclear yields, from a factor of â¼2 at 3.1 mg/cm3 to a factor of 100 at 0.14 mg/cm3. (The corresponding Knudsen number, the ratio of ion mean-free path to minimum shell radius, varied from 0.3 to 9; similarly, the ratio of fusion burn duration to ion diffusion time, another figure of merit of kinetic effects, varied from 0.3 to 14.) This result is shown to be unrelated to the effects of hydrodynamic mix. As a first step to garner insight into this transition, a reduced ion kinetic (RIK) model that includes gradient-diffusion and loss-term approximations to several transport processes was implemented within the framework of a one-dimensional radiation-transport code. After empirical calibration, the RIK simulations reproduce the observed yield trends, largely as a result of ion diffusion and the depletion of the reacting tail ions.
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We present a new approach to equation of state experiments that utilizes a laser-driven shock and release technique combined with spatially resolved x-ray Thomson scattering, radiography, velocity interferometry, and optical pyrometry to obtain independent measurements of pressure, density, and temperature for carbon at warm dense matter conditions. The uniqueness of this approach relies on using a laser to create very high initial pressures to enable a very deep release when the shock moves into a low-density pressure standard. This results in material at near normal solid density and temperatures around 10 eV. The spatially resolved Thomson scattering measurements facilitate a temperature determination of the released material by isolating the scattering signal from a specific region in the target. Our results are consistent with quantum molecular dynamics calculations for carbon at these conditions and are compared to several equation of state models.
Assuntos
Formas L/patogenicidade , Infecções Estreptocócicas/microbiologia , Streptococcus agalactiae/patogenicidade , Animais , Antígenos de Bactérias/análise , Epitopos/análise , Imunização , Formas L/imunologia , Camundongos , Coelhos , Ratos , Infecções Estreptocócicas/etiologia , Infecções Estreptocócicas/imunologia , Streptococcus agalactiae/imunologia , Fatores de TempoRESUMO
In a study of forty-two patients with dyspepsia, hiatus hernia or duodenal ulcer, dicyclomine (Merbentyl) has been demonstrated to be effective in the control of the symptoms of this disorder. Under double-blind conditions an antacid or placebo supplement was provided and no significant difference in benefit was recorded. The antacid was given in a large tablet and this preparation was more conscientiously taken by patients, and this was equally true for large placebo tablets. Clearly patients like to take frequent treatment for dyspepsia, but symptom control is quite adequate if Merbentyl is given alone.
Assuntos
Antiácidos/uso terapêutico , Ácidos Cicloexanocarboxílicos/uso terapêutico , Diciclomina/uso terapêutico , Dispepsia/tratamento farmacológico , Antiácidos/efeitos adversos , Diciclomina/efeitos adversos , Método Duplo-Cego , Avaliação de Medicamentos , Quimioterapia Combinada , HumanosRESUMO
The level of circulating immune complexes in the blood serum of patients with relapsing erysipelas was found to be correlated with the level of the antigen of group A S. haemolyticus L-forms, this antigen entering in to the composition of the immune complexes. In 68% of cases the antigen of the streptococcal L-forms was bound and only in 20% of cases, free. High titers of antibodies to group A S. haemolyticus L-forms in patients with relapsing erysipelas at the absence of free antigen indirectly suggests that the antigen is incorporated into antigen-antibody complexes.
Assuntos
Complexo Antígeno-Anticorpo/análise , Antígenos de Bactérias/análise , Erisipela/imunologia , Formas L/imunologia , Streptococcus pyogenes/imunologia , Anticorpos Antibacterianos/análise , Sítios de Ligação de Anticorpos , Epitopos/análise , Radicais Livres , Humanos , RecidivaRESUMO
Stable L-forms of group B streptococci (GBS) have been obtained and their antigenic features have been studied by the serological methods (the passive hemagglutination test, the aggregate agglutination test, the gel diffusion test), as well as by using ferritin and peroxidase labels with the subsequent electron microscopy. The use of the serological methods has made it possible to reveal the antigenic differences between the stable L-forms of GBS and their bacterial forms. Specific antigenic substances can be found in the supernatant fluid obtained after the sedimentation of the ultrasonically disintegrated cellular mass of streptococcal L-forms and bacterial cultures. The use of ferritin and peroxidase labels has revealed the specificity of GBS L-form antigen and its localization on the cytoplasmic membrane of all L-form structural elements.
Assuntos
Antígenos de Bactérias/análise , Formas L/imunologia , Streptococcus agalactiae/imunologia , Animais , Epitopos/análise , Imunização , Formas L/isolamento & purificação , Coelhos , Solubilidade , Streptococcus agalactiae/isolamento & purificação , Fatores de TempoAssuntos
Infecções por Mycoplasma/microbiologia , Adolescente , Adulto , Anticorpos Antibacterianos/análise , Autoanticorpos/análise , Criança , Feminino , Doenças dos Genitais Femininos/microbiologia , Doenças dos Genitais Masculinos/microbiologia , Humanos , Artropatias/imunologia , Artropatias/microbiologia , Masculino , Infecções por Mycoplasma/imunologia , Mycoplasma pneumoniae/imunologia , Mycoplasma pneumoniae/patogenicidade , Pneumonia por Mycoplasma/imunologia , Pneumonia por Mycoplasma/microbiologia , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Líquido Sinovial/imunologia , Líquido Sinovial/microbiologia , Doenças Urológicas/microbiologiaRESUMO
The time course of the distribution of M. fermentans antigen in the body of rabbits infected by a single intraperitoneal injection, as well as morphological and immunological changes occurring in the joints of the infected animals during 12 weeks of observation have been studied. M. fermentans, or its antigen, has been shown to persist mainly in immunocompetent organs and articular tissues, its localization in articular cartilage corresponding to the areas of dystrophic changes. The character of the pathological process in the joints is similar to rheumatoid arthritis in humans, which is confirmed by the results of immuno-morphological studies. The local synthesis of IgG and rheumatoid factor, the deposition of immune complexes and the presence of phagocytes in synovia have been detected.
Assuntos
Artrite/imunologia , Infecções por Mycoplasma/imunologia , Animais , Antígenos de Bactérias/análise , Artrite/patologia , Imunofluorescência , Articulações/imunologia , Mycoplasma/imunologia , Infecções por Mycoplasma/patologia , Coelhos , Sinovite/imunologia , Sinovite/patologia , Fatores de TempoRESUMO
A study has been conducted in general practice comparing two brands of lozenges, Merocaine (Merrell) and Tyrozets, (M.S.D.), in the management of acute sore throat and pharyngitis. Eighty-eight patients entered the between-patient study and each completed a diary card covering symptoms experienced and dosage used for each of the two drugs. The doctor reported upon the appearance of the throat and added antibiotics in cases of necessity, which was approximately for one-third of patients. Merocaine proved to be significantly superior to Tyrozets in producing rapid pain relief (within 15 minutes) and reduction of faucial and pharyngeal injection.