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1.
Ultramicroscopy ; 183: 19-29, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28705441

RESUMO

The combination of momentum microscopy (high resolution imaging of the Fourier plane) with an imaging spin filter has recently set a benchmark in k-resolution and spin-detection efficiency. Here we show that the degree of parallelization can be further increased by time-of-flight energy recording. On the quest towards maximum information (in earlier work termed "complete" photoemission experiment) we have studied the prototypical high-Z fcc metal iridium. Large partial bandgaps and strong spin-orbit interaction lead to a sequence of spin-polarized surface resonances. Soft X-rays give access to the 4D spectral density function ρ (EB,kx,ky,kz) weighted by the photoemission cross section. The Fermi surface and all other energy isosurfaces, Fermi velocity distribution vF(kF), electron or hole conductivity, effective mass and inner potential can be obtained from the multi-dimensional array ρ by simple algorithms. Polarized light reveals the linear and circular dichroism texture in a simple manner and an imaging spin filter exposes the spin texture. One-step photoemission calculations are in fair agreement with experiment. Comparison of the Bloch spectral function with photoemission calculations uncovers that the observed high spin polarization of photoelectrons from bulk bands originates from the photoemission step and is not present in the initial state.

2.
Eur Biophys J ; 38(1): 53-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18612633

RESUMO

We use photoemission electron microscopy in an X-ray transmission mode for full-field imaging of the X-ray absorption structure of copper in the respiratory metalloprotein hemocyanin KLH1. It contains 160 oxygen binding sites. Each site reversibly binds one molecule oxygen between two copper atoms. In our setup, hemocyanin is dissolved in aqueous solution and enclosed in an ultra-high vacuum compatible liquid sample cell with silicon nitride membranes. The local X-ray absorption structure of the liquid sample is converted into photoelectrons at the microscope side of the cell acting as a photocathode. In this way, different copper valencies are laterally distinguished under in vivo-like conditions, attributed to Cu(I) in the deoxy-state and Cu(II) in the oxy-state.


Assuntos
Hemocianinas/química , Hemocianinas/ultraestrutura , Microscopia Eletrônica de Transmissão/instrumentação , Oxigênio/química , Manejo de Espécimes/instrumentação , Espectrometria por Raios X/métodos , Sítios de Ligação , Desenho de Equipamento , Análise de Falha de Equipamento , Microscopia Eletrônica de Transmissão/métodos , Ligação Proteica , Conformação Proteica , Manejo de Espécimes/métodos
3.
Dysphagia ; 11(1): 72-4, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8556881

RESUMO

Acute thermal injury to the esophagus has not been reported previously in the radiographic literature. We present a case of a young adult who developed an intramural "blister" that ultimately communicated with the esophageal lumen. A double-contrast esophagogram outlined the resulting mucosal flap. A brief review of other injuries to the esophagus is included.


Assuntos
Queimaduras/etiologia , Esôfago/lesões , Adulto , Vesícula/etiologia , Queimaduras/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Esôfago/diagnóstico por imagem , Feminino , Alimentos , Humanos , Radiografia
4.
J Manipulative Physiol Ther ; 18(9): 582-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8775019

RESUMO

OBJECTIVE: To evaluate the short-term responsiveness of rotatory thoracic end-play assessment to spinal manipulation and, thereby, motion palpation construct validity. DESIGN: Prospective, single-blind, randomized, controlled trial (randomized blocks design). SETTING: Laboratory, Center for Technique Research. PARTICIPANTS: Sixty first-year chiropractic college student volunteers; seventy-three possible candidates were screened. INTERVENTIONS: The treatment group received manual high-velocity, low-amplitude rotatory manipulation. The control group received no intervention to minimize nonspecific effects of sham treatment. MAIN OUTCOME MEASURES: End-play response, defined as the change from restricted to normal end play immediately after intervention. Responsiveness, defined as the percentage of the end-play response attributable to spinal manipulation: relative response attributable to the maneuver, RRAM = (treatment group response--control group response)/treatment group response. RESULTS: Ten percent of the tests were positive for restriction of end play in left or right rotation from T3-T4 to T12-L1; the average rate was 2.1 restrictions per subject (SD = 1.4). End-play response was 60% in the treatment group, in contrast to the 37% response in the control group (z = 1.86, p = .04). More than a third of the response in the treatment group was attributable to spinal manipulation (RRAM = 39%). For one examiner, RRAM = 51%. Mild symptomatology did not affect responsiveness. CONCLUSIONS: The data suggest a moderate short-term responsiveness of rotatory thoracic end-play restriction to spinal manipulation, hence it has utility as a posttreatment evaluative test. This study was the first to use an external standard (manipulation) to demonstrate that segmental end-play restriction changes, hence end-play restriction itself, are detectable in human subjects with manual palpation by chiropractors. Further research is required to determine the generalizability of the study findings.


Assuntos
Quiroprática/métodos , Doenças da Coluna Vertebral/terapia , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Estudos Prospectivos , Método Simples-Cego , Vértebras Torácicas , Resultado do Tratamento
5.
Urology ; 43(3): 365-9, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8134992

RESUMO

OBJECTIVE: To compare the effectiveness of topically applied 2% minoxidil to that of intracorporeal injection therapy and vacuum constriction devices for the treatment of erectile dysfunction in the spinal cord injured (SCI) male. METHODS: Eighteen SCI men, aged nineteen to sixty-five years (median age, 29), and level of injury C7 to L3 (15 thoracic level) were prospectively evaluated. All patients were able to achieve only a poorly sustained reflex erection that was inadequate for satisfactory intercourse. No patient had suffered erectile dysfunction prior to his SCI. In each patient, 1 mL of a 2% minoxidil solution was applied as an aerosol spray to the glans penis. The erectile response was compared to that obtained with a vacuum constriction device (VCD) and intracorporeal papaverine injection. In each case, the subjective assessment by both the patient and the physician, as well as objective results of penile base rigidity as measured by the RigiScan DT Monitor Device, were recorded. RESULTS: Papaverine increased rigidity at the base of the penis by a median 77 percent (range, 30-100%). The VCD increased rigidity by a median 57 percent (range, 30-80%). Minoxidil induced no change in rigidity (range, 0-15%). No complications were observed for any method of inducing tumescence. CONCLUSIONS: Papaverine and VCD proved to be effective means of establishing penile erection in male SCI patients. Both subjective and objective erectile responses to minoxidil were poor. Nevertheless, the principle of topical therapy is an attractive alternative to existing modalities. Further investigation is warranted.


Assuntos
Disfunção Erétil/terapia , Minoxidil/uso terapêutico , Papaverina/uso terapêutico , Traumatismos da Medula Espinal/complicações , Administração Tópica , Adulto , Idoso , Terapia Combinada , Constrição , Disfunção Erétil/etiologia , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Minoxidil/administração & dosagem , Papaverina/administração & dosagem , Pênis , Estudos Prospectivos , Resultado do Tratamento , Vácuo
6.
J Manipulative Physiol Ther ; 16(5): 306-11, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8345313

RESUMO

OBJECTIVE: A study was undertaken to assess the stability of leg alignment reaction to a pressure challenge and its responsiveness to an adjustive intervention. DESIGN: Prospective, double-blind clinical trial of a diagnostic test. SETTING: Laboratory: Center for Technique Research. PARTICIPANTS: Forty-two chiropractic college students, faculty and staff. INTERVENTIONS: A high-velocity, low-amplitude, short lever adjustment of a single vertebra from among C1 and T3-T7; or a sham adjustment similar to a manual diagnostic pressure test at C1, T3-T7 or T9-T10. MAIN OUTCOME MEASURES: Leg alignment reactivity: An increase in leg alignment discrepancy (yes or no) following a metered pressure challenge to a vertebra. RESULTS: On average, stability was poor at T3-T7 (Kappa = 0.04), moderate at C1 (K = 0.47), and fair for sham pressure tests (K = 0.30). Responsiveness: The proportion of positive baseline leg alignment reactions that responded (became negative) to sham adjustment was 95% at T3-T7 and 55% at C1. Further analysis was untenable since too few vertebrae were implicated for an adjustment. CONCLUSIONS: For the population investigated, the majority of the responsiveness of the leg alignment diagnostic test to a rotatory adjustment appears to be a diagnostic illusion (i.e., background noise unrelated to a treatment intervention). Further research with different subject populations, regions of investigation, leg alignment measurement techniques and vertebral challenge techniques are indicated.


Assuntos
Perna (Membro)/patologia , Manipulação Ortopédica/normas , Projetos de Pesquisa , Doenças da Coluna Vertebral/diagnóstico , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Manipulação Ortopédica/métodos , Manometria , Pessoa de Meia-Idade , Pressão , Estudos Prospectivos , Doenças da Coluna Vertebral/patologia , Doenças da Coluna Vertebral/fisiopatologia , Doenças da Coluna Vertebral/terapia
7.
J Manipulative Physiol Ther ; 16(4): 220-7, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8340716

RESUMO

OBJECTIVE: A study was undertaken to assess the reliability of detecting leg alignment changes (reactivity) and to determine if the observed leg alignment reactivity can be attributed to a rotatory articular pressure challenge. DESIGN: Prospective double-blind crossover trial of a diagnostic test. SETTING: Laboratory: Center for Technique Research. PARTICIPANTS: Forty-two chiropractic college students, faculty and staff. INTERVENTIONS: A standardized force of 2 or 3 kg was applied with a 1 cm2 rubber-tipped pressure algometer on the lateral aspect of the T3-T7 spinous processes and the posterior aspect of the lateral masses of C1. MAIN OUTCOME MEASURES: Leg alignment reactivity: an increase in leg alignment discrepancy (yes or no) following a diagnostic intervention. RESULTS: The reliability for detecting leg alignment reactivity was poor: on average, Kappa = 0.05 in the thoracics and 0.06 at C1. On average, the attributable risk of leg alignment reactivity (pressure test risk--sham test risk) was less than 4%. In many cases, the sham rate was greater than the pressure test rate. CONCLUSIONS: For the population investigated, leg alignment reactivity to rotatory pressure testing can, in the majority of cases, be attributable to background noise. This procedure was not found to be viable for identifying vertebrae for adjustment. Further research with different subject populations, regions of investigation, leg alignment measurement techniques and vertebral challenge techniques are indicated.


Assuntos
Quiroprática/métodos , Perna (Membro)/fisiologia , Pressão , Vértebras Torácicas/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
8.
J Manipulative Physiol Ther ; 15(8): 518-24, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1402412

RESUMO

OBJECTIVE: This review surveys the literature regarding reliability studies of lumbar motion palpation. DATA SOURCES: Using the indexing terms motion palpation lumbar spine and palpation, the following English language databases were surveyed: a) Medline, including back file; b) Embase; c) Cinahl; and d) Epic. Additionally, a manual search of the Chiropractic Research Archives Collection and JMPT was performed and researchers at Western States Chiropractic College were consulted. Pertinent references cited in bibliographies of retrieved papers were included if contributory. STUDY SELECTION: Studies pertaining to intra- and interexaminer reliability of lumbar motion palpation were reviewed. DATA EXTRACTION: Statistical analysis, subject selection, method of palpation and sources of error are discussed. DATA SYNTHESIS: Multiple variations were noted in type of palpation, subjects examined, statistical analysis and experience of examiners. CONCLUSIONS: To date, most studies have demonstrated marginal to poor interexaminer reliability, while good to moderate intrarater reliability has generally been reported.


Assuntos
Vértebras Lombares/fisiologia , Movimento , Palpação , Dor nas Costas/diagnóstico , Humanos , Dor Lombar/diagnóstico , Variações Dependentes do Observador , Reprodutibilidade dos Testes
16.
Arch Geschwulstforsch ; 52(5): 407-22, 1982.
Artigo em Alemão | MEDLINE | ID: mdl-6293401

RESUMO

The basis for a scientific aftercare are such characteristics as recurrence and metastasis rates, lethality classified according to age-groups and duration of observation. Comparable data like 5-years-lethality by age-groups in 1968 and 1973 (female patients with cancer of the breast diagnosed in the capital of the G.D.R., Berlin), causes of death, cumulative relative survival rates, excess mortality are of importance for the follow-up intensity directed to this group of patients by the cancer centre, the general-practitioner and the out-patient oncological department. The most important task will still be early diagnosis of malignant tumours, because detection of curable stages will have better results and such patients need less intensive aftercare.


Assuntos
Assistência ao Convalescente , Neoplasias da Mama/epidemiologia , Adulto , Fatores Etários , Idoso , Berlim , Neoplasias da Mama/mortalidade , Feminino , Seguimentos , Alemanha Oriental , Humanos , Pessoa de Meia-Idade , Prognóstico
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