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1.
Tech Coloproctol ; 23(6): 611, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31168776

RESUMEN

Unfortunately, the "Informed consent" statement was incorrectly published in the original version. The complete correct reference should read as follows.

2.
Tech Coloproctol ; 23(4): 325-332, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31016550

RESUMEN

BACKGROUND: The aim of the present study was to evaluate patient factors that affect the progression of anal dysplasia in human immunodeficiency virus (HIV)-positive individuals. METHODS: A retrospective cohort study of HIV-positive adults with human papilloma virus related anal lesions was performed from 2012 to 2017. All patients underwent surgical excision or biopsy and fulguration of lesions in the operating room without using high resolution anoscopy. Patients with initial presentation of squamous cell carcinoma were excluded. The study was designed to investigate progression between the first available histology and either the follow up histology or a negative examination. Patient files were reviewed and data was collected. A bivariate analysis of continuous and categorical variables was performed. RESULTS: One hundred and sixty-one patients met the inclusion criteria. Ninety-seven percent were male. Mean age was 41 years. Thirty-five percent were African American and 47% were Caucasian. After a median follow-up interval of 331 days (IQR 120-615 days) 14 (9%) of patients had progression of disease. Visible lesions on initial presentation, as opposed to lesions found  in patients undergoing examination under anesthesia because of HSIL on anal pap smear, was associated with progression (p = 0.0.2). A lower initial CD4 count (p = 0.01) and initial surgical pathology of anal condylomata (p = 0.01) were also associated with progression. High-risk serotype was associated with no change or regression (p = 0.01). CONCLUSIONS: In our large cohort of HIV-positive patients treated without high resolution anoscopy the rate of progression was low.  Most notably, visible lesions at initial presentation and CD4 count when lower were associated with progression. Initial surgical pathology of anal condylomata was associated with progression, while high-risk serotypes correlated with regression or stability. Identification of risk factors has important implications concerning postoperative surveillance and counseling of HIV-positive patients with anal condylomata/ anal dysplasia.


Asunto(s)
Neoplasias del Ano/patología , Carcinoma in Situ/patología , Carcinoma de Células Escamosas/patología , Infecciones por VIH/patología , VIH , Adulto , Canal Anal/patología , Canal Anal/virología , Neoplasias del Ano/virología , Biopsia , Carcinoma in Situ/virología , Carcinoma de Células Escamosas/virología , Condiloma Acuminado/patología , Condiloma Acuminado/virología , Progresión de la Enfermedad , Femenino , Infecciones por VIH/virología , Humanos , Masculino , Proctoscopía , Estudios Retrospectivos , Factores de Riesgo
3.
Rev Sci Instrum ; 79(3): 033502, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18377005

RESUMEN

A retarding field energy analyzer designed to measure ion energy distributions impacting a radio-frequency biased electrode in a plasma discharge is examined. The analyzer is compact so that the need for differential pumping is avoided. The analyzer is designed to sit on the electrode surface, in place of the substrate, and the signal cables are fed out through the reactor side port. This prevents the need for modifications to the rf electrode--as is normally the case for analyzers built into such electrodes. The capabilities of the analyzer are demonstrated through experiments with various electrode bias conditions in an inductively coupled plasma reactor. The electrode is initially grounded and the measured distributions are validated with the Langmuir probe measurements of the plasma potential. Ion energy distributions are then given for various rf bias voltage levels, discharge pressures, rf bias frequencies--500 kHz to 30 MHz, and rf bias waveforms--sinusoidal, square, and dual frequency.

4.
Opt Express ; 15(21): 13913-23, 2007 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-19550663

RESUMEN

Real time closed loop control of plasma assisted semiconductor manufacturing processes has received significant attention in recent years. Therefore we have developed and tested a customized optical sensor based on buffer gas (argon) actinometry which has been used to determine relative densities of atomic and molecular oxygen in an Ar/O(2) radio-frequency ICP chamber. The operation and accuracy of our optical sensor compared favorably with a high resolution commercial spectrometer but at lower cost and exhibited improved actinometric performance over a low resolution commercial spectrometer. Furthermore, threshold tests have been performed on the validity of buffer gas based actinometry in Ar/O(2) ICP plasmas where Ar is no longer a trace gas through Xe actinometry. The plasma conditions for which this customized optical sensor can be used for closed loop control have been established.

5.
Rev Sci Instrum ; 78(1): 016102, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17503951

RESUMEN

The authors report on an experimental system designed to investigate and characterize capacitive radio frequency (rf) sheaths. An electrode mounted in an inductive plasma reactor and driven with separate rf and direct current (dc) power sources is used. The advantage of this design is that the electrode sheath is decoupled from the plasma parameters. This allows detailed investigation of the sheath with different bias conditions without perturbing the bulk plasma parameters. Power coupled to ions and electrons through the sheath, at low pressure, is investigated and a method to determine the electron conduction current to the electrode, using the external dc bias, is presented.


Asunto(s)
Capacidad Eléctrica , Electrones , Iones , Electrodos , Presión
6.
Rev Sci Instrum ; 87(4): 043511, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27131678

RESUMEN

A compact retarding field analyzer with embedded quartz crystal microbalance has been developed to measure deposition rate, ionized flux fraction, and ion energy distribution arriving at the substrate location. The sensor can be placed on grounded, electrically floating, or radio frequency (rf) biased electrodes. A calibration method is presented to compensate for temperature effects in the quartz crystal. The metal deposition rate, metal ionization fraction, and energy distribution of the ions arriving at the substrate location are investigated in an asymmetric bipolar pulsed dc magnetron sputtering reactor under grounded, floating, and rf biased conditions. The diagnostic presented in this research work does not suffer from complications caused by water cooling arrangements to maintain constant temperature and is an attractive technique for characterizing a thin film deposition system.

7.
Rev Sci Instrum ; 86(11): 113501, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26628129

RESUMEN

A new technique is presented to measure the angular distribution of plasma ions bombarding the substrate surface with a planar retarding field analyzer. By varying the effective aspect ratio of the analyzer's aperture, ions with different angular spread that are allowed through the device for detection are controlled. The analytical theory developed to define the ion current as a function of incident ion angle, ion energy, aperture geometry, and aspect ratio is shown. The method used to vary the effective aspect ratio of the aperture is also discussed. The mathematical theory is derived and the numerical solution discussed. Ion energy distributions, as a function of ion angle, with resolution as low as 3° can be measured.

8.
Neurology ; 43(7): 1401-6, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8327145

RESUMEN

We treated 13 patients with progressive MS with mitoxantrone. All patients received a standard IV dose of mitoxantrone (8 mg/m2) every 3 weeks for a total of seven infusions, with dosage adjustments depending on the hematologic profile at the nadir. The treatment was well tolerated, with the most common side effect being mild nausea. Four of seven women developed transient secondary amenorrhea. The postenrollment clinical behavior of these patients was generally more favorable than during the 18 months prior to enrollment (only three of 13 patients developed an increase in the Expanded Disability Status Scale of more than 0.5 points), suggesting a possible treatment effect, but comparison with two historical control groups (both the active and placebo groups from the Canadian Cooperative Trial of Cyclophosphamide and Plasma Exchange) does not suggest that mitoxantrone was efficacious. Eight of 12 patients had evidence of MRI activity on 13 of 29 follow-up visits. This small, open-labeled pilot study did not provide strong support for proceeding with a randomized, controlled trial of this dosage regimen of mitoxantrone in patients with progressive MS.


Asunto(s)
Mitoxantrona/uso terapéutico , Esclerosis Múltiple/tratamiento farmacológico , Adulto , Encéfalo/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Mitoxantrona/administración & dosificación , Esclerosis Múltiple/patología , Esclerosis Múltiple/fisiopatología , Proyectos Piloto
9.
Hum Pathol ; 16(9): 873-84, 1985 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2993152

RESUMEN

Advances in radioimmunoassay procedures, immunocytochemistry, neuroradiologic imaging, and the surgical and medical treatment of pituitary adenomas have led to reappraisal of their classification as well as refinements in the diagnostic approaches used by pathologists. Sixty-two pituitary adenomas are described, and recent advances in this field are reviewed. Most of the patients were adults, but one of the adrenocorticotropic hormone (ACTH)-producing adenomas occurred in an 11-month-old infant. Endocrine-inactive tumors (43.5 per cent) were less common than hormone-producing tumors (56.5 per cent). Local invasion was most common in the former group, followed by ACTH-producing and other hormone-producing tumors. Ultrastructural features correlated with hormonal levels in the growth hormone(GH)-secreting tumors but not in the prolactin(LTH)- or ACTH-producing tumors. The formation of 7-nm filaments in the cytoplasm of tumor cells, corresponding to Crooke's hyaline change on light microscopy, was characteristic of ACTH-producing tumors. Ultrastructural changes in the ACTH granules suggested that the filaments may be derived from the feedback action of cortisol. Prior to surgery, a Rathke's cleft cyst and a chordoma were mistaken for endocrine-inactive pituitary adenomas. In two additional cases ectopic ACTH-producing tumors of lung clinically mimicked pituitary adenoma. Conversely, one pituitary adenoma mimicked sphenoid wing meningioma. Clinical, hormonal, and radiologic data and immunocytochemical and electron microscopic studies are needed for accurate pathologic interpretation and classification of pituitary adenomas.


Asunto(s)
Adenoma/ultraestructura , Neoplasias Hipofisarias/ultraestructura , Adenoma/clasificación , Adenoma/metabolismo , Adenoma/fisiopatología , Adolescente , Hormona Adrenocorticotrópica/biosíntesis , Adulto , Anciano , Niño , Preescolar , Glándulas Endocrinas/fisiopatología , Femenino , Hormona del Crecimiento/biosíntesis , Humanos , Lactante , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Neoplasias Hipofisarias/clasificación , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/fisiopatología , Prolactina/biosíntesis
10.
Am J Clin Pathol ; 106(4): 504-10, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8853040

RESUMEN

Pulmonary alveolar proteinosis (PAP) is an uncommon disease in which alveoli are progressively filled with surfactant-related material. Although a definitive diagnosis is usually made by an open lung biopsy, bronchoalveolar lavage (BAL) cytology may play a decisive role in the clinical work-up of these patients, and, in some cases, may spare a patient a more invasive diagnostic procedure. The authors present three patients in whom BAL cytology specimens contained the characteristic (although not specific) globules of amorphous proteinaceous PAS-positive material accompanied by only rare background macrophages and inflammatory cells. The patients include a 40-year-old man with an 8-year history of fever of unknown origin, a 30-year-old man with a chronic nonproductive cough, and a 6-year-old boy diagnosed at 5 months of age with osteopetrosis and hypogammaglobulinemia who subsequently developed a disseminated Mycobacterium avium-intracellulare infection. All specimens stained with Gomori methenamine silver (3) and Ziehl-Neelsen (2) were negative for microbial organisms, Ultrastructural examination of two specimens revealed the characteristic lamellar structures of surfactant, increasing diagnostic specificity. Lung biopsies and/or autopsy subsequently confirmed the diagnosis in all three cases. The characteristic cytologic and ultrastructural features of PAP in BAL specimens are presented along with the morphologic differential features of other entities which potentially could be confused with PAP.


Asunto(s)
Líquido del Lavado Bronquioalveolar/citología , Proteinosis Alveolar Pulmonar/patología , Adulto , Biopsia , Niño , Humanos , Masculino , Microscopía Electrónica , Infección por Mycobacterium avium-intracellulare/patología , Alveolos Pulmonares/patología , Alveolos Pulmonares/ultraestructura
11.
Cell Transplant ; 9(3): 359-68, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10972335

RESUMEN

Cellular cardiomyoplasty (CCM), or introduction of immature cells into terminally injured heart, can mediate repair of chronically injured myocardium. Several different cell types, ranging from embryonic stem cells to autologous skeletal myoblasts, have been successfully propagated within damaged heart and shown to improve myocardial performance. However, it is unclear if the functional advantages associated with CCM depend upon the use of myogenic cells or if similar results can be seen with other cell types. Thus, we compared indices of regional contractile (systolic) and diastolic myocardial performance following transplantation of either autologous skeletal myoblasts (Mb) or dermal fibroblasts (Fb) into chronically injured rabbit heart. In vivo left ventricular (LV) pressure (P) and regional segment length (SL) were determined in 15 rabbits by micromanometry and sonomicrometry 1 week following LV cryoinjury (CRYO) and again 3 weeks after autologous skeletal Mb or dermal Fb transplantation. Quantification of systolic performance was based on the linear regression of regional stroke work and end-diastolic (ED) SL. Regional diastolic properties were assessed using the curvilinear relationships between LVEDP and strain (epsilon) as well as LVEDP and EDSL. At study termination, cellular engraftment was characterized histologically in a blinded fashion. Indices of diastolic performance were improved following CCM with either Mb or Fb. However, only Mb transplantation improved systolic performance; Fb transfer actually resulted in a significant decline in systolic performance. These data suggest that both contractile and noncontractile cells can improve regional material properties or structural integrity of terminally injured heart, as reflected by improvements in diastolic performance. However, only Mb improved systolic performance in the damaged region, supporting the role of myogenic cells in augmenting contraction. Further studies are needed to define the mechanism by which these effects occur and to evaluate the long-term safety and efficacy of CCM with any cell type.


Asunto(s)
Cardiomioplastia/métodos , Trasplante de Células , Fibroblastos/trasplante , Corazón/fisiología , Músculo Esquelético/citología , Animales , Cardiomiopatías/patología , Cardiomiopatías/cirugía , Diástole , Corazón/anatomía & histología , Humanos , Microscopía Fluorescente , Músculo Esquelético/trasplante , Miocardio/citología , Miocardio/patología , Conejos , Piel/citología , Sístole , Trasplante Autólogo
12.
Clin Neuropharmacol ; 24(6): 341-5, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11801809

RESUMEN

Magnesium sulfate has attracted interest as a potential neuroprotectant but passage of magnesium ion into the central nervous system has not been well documented. For this study, we quantified plasma and cerebrospinal fluid (CSF) ionized magnesium concentration after systemic magnesium sulfate infusion in patients with intracranial hypertension. Patients ( N = 9) received an intravenous infusion of 5 g/20 mmol magnesium sulfate (125 mL of a 4% wt/vol solution) over 30 minutes. Before and after dosing, CSF (from an indwelling ventricular catheter) and blood samples were collected at hourly intervals. Ionized magnesium concentration in all samples was determined using an electrolyte analyzer. Baseline plasma and CSF ionized magnesium concentrations were 0.58 +/- 0.05 and 0.82 +/- 0.06 mmol/L, respectively. Intravenous magnesium sulfate infusion significantly increased plasma ionized magnesium concentration (peak, 0.89 +/- 0.11 mmol/L), but CSF magnesium levels did not change during the 4-hour study. Systemic administration of magnesium sulfate failed to increase CSF ionized magnesium concentration in patients with intracranial hypertension despite increasing plasma magnesium levels by >50%.


Asunto(s)
Ventrículos Cerebrales/metabolismo , Hipertensión Intracraneal/líquido cefalorraquídeo , Sulfato de Magnesio/farmacología , Magnesio/líquido cefalorraquídeo , Adolescente , Adulto , Anciano , Ventrículos Cerebrales/efectos de los fármacos , Femenino , Humanos , Infusiones Intravenosas , Hipertensión Intracraneal/sangre , Hipertensión Intracraneal/metabolismo , Magnesio/sangre , Sulfato de Magnesio/administración & dosificación , Masculino , Persona de Mediana Edad , Fármacos Neuroprotectores/farmacología
13.
Arch Pathol Lab Med ; 110(3): 219-23, 1986 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3753855

RESUMEN

A menu-driven computer program that utilizes a data base of commercial panels was developed to assist in the identification and confirmation of red blood cell antibodies. A selected panel, along with the corresponding serum reactions, is displayed on the monitor and possible antibody patterns including dosage-dependent patterns are highlighted. A panel interpretation is then printed that includes a list of the possible (nonexcluded) antibodies, a probability level of identification for each possible antibody, and a table of antibody characteristics to aid in the differentiation among the possible antibodies. The panel data base can also be searched for additional red blood cells of specified phenotypes to confirm each suspected antibody. These additional red blood cells may be combined into a temporary panel for computer analysis. The program can also enter, print, edit, and delete any commercial panel from the data base. This computer program has proved to be faster and more accurate than the standard manual method for panel analysis, especially when multiple antibodies are present.


Asunto(s)
Anticuerpos/análisis , Computadores , Eritrocitos/inmunología , Programas Informáticos , Bancos de Sangre/organización & administración , Humanos
14.
Arch Pathol Lab Med ; 112(5): 564-6, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3358659

RESUMEN

Psammoma bodies associated with cancer cells of ovarian and endometrial origins have been previously described in cervicovaginal smears, as have psammoma bodies from totally benign processes. We describe the presence of numerous psammoma bodies in the cervical smear, endometrial curettage, and peritoneal wash specimens from a patient with subsequently discovered bilateral, ovarian, borderline serous tumors. We morphologically traced the transit of these psammoma bodies and their associated cytologically benign tumor cells through the entire female genital tract.


Asunto(s)
Neoplasias Ováricas/patología , Ovario/patología , Trompas Uterinas/patología , Femenino , Humanos , Persona de Mediana Edad , Pronóstico , Útero/patología , Frotis Vaginal
15.
Arch Pathol Lab Med ; 118(5): 566-7, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8192566

RESUMEN

A 19-year-old man died of a disseminated herpesvirus infection. Microscopic examination of a peritoneal fluid specimen revealed cellular changes characteristic of a herpetic process, and an autopsy confirmed widespread herpes simplex virus type II infection. Viral infections may be diagnosed by cytologic examination of body fluid specimens.


Asunto(s)
Líquido Ascítico/citología , Hepatitis/microbiología , Herpes Simple , Adulto , Hepatitis/patología , Herpes Simple/mortalidad , Humanos , Masculino , Simplexvirus
16.
J Res Natl Inst Stand Technol ; 100(4): 415-425, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-29151751

RESUMEN

The use of a Langmuir probe system in two GEC cells is reviewed. The major problems associated with probe diagnostics in a GEC cell are outlined and discussed. While the data base is still insufficient to give definitive values for many parameters, a number of standard measurements are put forward. The plasma density in argon is 9×109 cm-3 (±20 %) at an applied rf voltage of 250 V (500 V peak to peak) and a gas pressure of 13.3 Pa (100 mTorr). The electron density scales linearly with applied voltage. The plasma to ground sheath resistance is shown to be very important with a value of 810 Ω in argon at a pressure of 13.3 Pa (100 mTorr) and discharge current of 0.1 A. The value of plasma to ground resistance scales inversely with discharge current and sublinear with pressure. Two standard features in the electron energy distribution function (EEDF) have been proposed as a test of the ability of a probe system to resolve features, first, the transition from a low temperature (<1 eV) bi-Maxwellian distribution to a Druyveysten distribution (3 eV) at 13.3 Pa (100 mTorr) in argon, and the "hole" in the EEDF at 2 eV to 4 eV in nitrogen plasmas.

17.
Acta Cytol ; 41(6): 1839-44, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9390154

RESUMEN

BACKGROUND: Fine needle aspiration biopsy (FNAB) affords a less expensive, less morbid approach to masses within the complex anatomy of the mediastinum as opposed to surgical biopsy. Given the current state of computed tomography guidance and the available cell block preparations and ancillary studies, definitive diagnosis of mediastinal tumors is possible. CASE: A 19-year-old male presented with weight loss and muscle weakness. Computed tomography revealed an anterior superior mediastinal mass with attachment to the posterior sternum and anterior aorta. FNAB yielded hyperchromatic cells with densely clumped chromatin and prominent nucleoli. These were present as single cells and clusters. Cell block preparations were studied with immunoperoxidase methods and were strongly positive for chromogranin and glucagon, supporting the diagnosis of carcinoid tumor. Surgical excision yielded a 7-cm, unencapsulated, red-brown tumor with medium-sized cells with oval to round nuclei, scant and granular cytoplasm and coarse "salt and pepper" chromatin with prominent nucleoli. The cells were arranged in islands and bands and were associated with prominent capillaries and dense, collagenous septae. Immunoperoxidase and electron microscopy demonstrated numerous intracytoplasmic, nonspecific neurosecretory granules and positivity for somatostatin, synaptophysin, cytokeratin and chromogranin. CONCLUSION: FNAB affords an accurate and timely diagnosis of an anterior mediastinal tumor without the necessity for open biopsy and also offers accurate surgical planning and decreased morbidity.


Asunto(s)
Tumor Carcinoide/patología , Neoplasias del Timo/patología , Adulto , Biomarcadores de Tumor/análisis , Biopsia con Aguja/métodos , Tumor Carcinoide/diagnóstico por imagen , Tumor Carcinoide/cirugía , Tumor Carcinoide/ultraestructura , Nucléolo Celular/patología , Cromatina/patología , Cromograninas/análisis , Gránulos Citoplasmáticos/patología , Gránulos Citoplasmáticos/ultraestructura , Glucagón/análisis , Humanos , Masculino , Neoplasias del Timo/diagnóstico por imagen , Neoplasias del Timo/cirugía , Neoplasias del Timo/ultraestructura , Tomografía Computarizada por Rayos X
18.
Acta Cytol ; 37(6): 943-7, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-7504382

RESUMEN

Combined hepatocellular-cholangiocarcinoma (HCC-CC) is rare, constituting much less than 5% of all primary liver cancers. Its dual histologic and cytologic differentiation may be a major problem in the differential diagnosis of fine needle aspiration biopsies (FNABs) of the liver. We describe two cases of combined HCC-CC, both examined initially by FNAB. Cytologic smears were markedly cellular, with a population of slightly to moderately pleomorphic neoplastic cells, often arranged in cohesive cords and columns resembling anastomosing hepatic plates. Many of these cells had centrally placed nuclei and a moderate amount of granular, eosinophilic cytoplasm. Other cellular groups were arranged in acinar formations, with eccentric nuclei and intraluminal and cytoplasmic mucin production. Both types of cells were positive for cytokeratin and carcinoembryonic antigen; in one case the carcinoma cells were also focally positive for alpha-fetoprotein. Although these neoplasms may pose diagnostic challenges, our experience suggests that HCC-CC may be suspected or even diagnosed by FNAB.


Asunto(s)
Carcinoma Hepatocelular/patología , Colangiocarcinoma/patología , Neoplasias Hepáticas/patología , Hígado/patología , Adulto , Anciano , Biopsia con Aguja , Antígeno Carcinoembrionario/análisis , Carcinoma Hepatocelular/química , Carcinoma Hepatocelular/diagnóstico , Núcleo Celular/ultraestructura , Colangiocarcinoma/química , Colangiocarcinoma/diagnóstico , Citoplasma/química , Citoplasma/ultraestructura , Femenino , Humanos , Inmunohistoquímica , Queratinas/análisis , Neoplasias Hepáticas/química , Neoplasias Hepáticas/diagnóstico , Masculino , Mucinas/análisis , alfa-Fetoproteínas/análisis
19.
Int J Clin Exp Hypn ; 39(3): 134-9, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1894386

RESUMEN

2 studies are reported, one using hypnotized Ss selected on hypnotizability and one using Ss selected on imagery vividness, whose purpose is to examine whether non-patient Ss can control their bleeding in a laboratory setting. All Ss were cut on both arms with the "Surgicutt" device, an instrument that automatically makes a cut that will bleed from 2 to 10 minutes. Results suggest that Ss, who are instructed to reduce the bleeding time in one arm and to let the other arm bleed normally, are not able to control bleeding time.


Asunto(s)
Tiempo de Sangría , Hipnosis , Imaginación/fisiología , Adulto , Humanos , Sugestión
20.
Rev Sci Instrum ; 85(4): 043509, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24784609

RESUMEN

A novel retarding field energy analyzer design capable of measuring the spatial uniformity of the ion energy and ion flux across the surface of a semiconductor wafer is presented. The design consists of 13 individual, compact-sized, analyzers, all of which are multiplexed and controlled by a single acquisition unit. The analyzers were tested to have less than 2% variability from unit to unit due to tight manufacturing tolerances. The main sensor assembly consists of a 300 mm disk to mimic a semiconductor wafer and the plasma sampling orifices of each sensor are flush with disk surface. This device is placed directly on top of the rf biased electrode, at the wafer location, in an industrial capacitively coupled plasma reactor without the need for any modification to the electrode structure. The ion energy distribution, average ion energy, and average ion flux were measured at the 13 locations over the surface of the powered electrode to determine the degree of spatial nonuniformity. The ion energy and ion flux are shown to vary by approximately 20% and 5%, respectively, across the surface of the electrode for the range of conditions investigated in this study.

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