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1.
Phys Rev Lett ; 126(14): 141801, 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33891447

RESUMEN

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{µ}≡(g_{µ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{µ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both µ^{+} and µ^{-}, the new experimental average of a_{µ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

2.
Adv Colloid Interface Sci ; 232: 25-35, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26969281

RESUMEN

Arteriosclerosis with its clinical sequelae (cardiac infarction, stroke, peripheral arterial occlusive disease) and vascular/Alzheimer dementia not only result in far more than half of all deaths but also represent dramatic economic problems. The reason is, among others, that diabetes mellitus is an independent risk factor for both disorders, and the number of diabetics strongly increases worldwide. More than one-half of infants in the first 6months of life have already small collections of macrophages and macrophages filled with lipid droplets in susceptible segments of the coronary arteries. On the other hand, the authors of the Bogalusa Heart Study found a strong increase in the prevalence of obesity in childhood that is paralleled by an increase in blood pressure, blood lipid concentration, and type 2 diabetes mellitus. Thus, there is a clear linkage between arteriosclerosis/Alzheimer's disease on the one hand and diabetes mellitus on the other hand. Furthermore, it has been demonstrated that distinct apoE isoforms on the blood lipids further both arteriosclerotic and Alzheimer nanoplaque formation and therefore impair flow-mediated vascular reactivity as well. Nanoplaque build-up seems to be the starting point for arteriosclerosis and Alzheimer's disease in their later full clinical manifestation. In earlier work, we could portray the anionic biopolyelectrolytes syndecan/perlecan as blood flow sensors and lipoprotein receptors in cell membrane and vascular matrix. We described extensively molecular composition, conformation, form and function of the macromolecule heparan sulfate proteoglycan (HS-PG). In two supplementary experimental settings (ellipsometry, myography), we utilized isolated HS-PG for in vitro nanoplaque investigations and isolated human coronary artery segments for in vivo tension measurements. With the ellipsometry-based approach, we were successful in establishing a direct connection on a molecular level between diabetes mellitus on the one side and arteriosclerosis/Alzheimer's disease on the other side. Application of glucose at a concentration representative for diabetics and leading to glycation of proteins and lipids, entailed a significant increase in arteriosclerotic and Alzheimer nanoplaque formation. IDLapoE4/E4 was by far superior to IDLapoE3/E3 in plaque build-up, both in diabetic and non-diabetic patients. Recording vascular tension of flow-dependent reactivity in blood substitute solution and under application of different IDLapoE isoforms showed an impaired vasorelaxation for pooled IDL and IDLapoE4/E4, thus confirming the ellipsometric investigations. Incubation in IDLapoE0/E0 (apoE "knockout man"), however, resulted in a massive flow-mediated contraction, also complemented by strongly aggregated nanoplaques. In contrast, HDL was shown to present a powerful protection against nanoplaque formation on principle, both in the in vitro model and the in vivo scenario on the endothelial cell membrane. The competitive interplay with LDL is highlighted through the flow experiment, where flow-mediated, HDL-induced vasodilatation remains untouched by additional incubation with LDL. This is due to the four times higher affinity for the proteoglycan receptor of HDL as compared to LDL. Taken together, the studies demonstrate that while simplistic, the ellipsometry approach and the endothelial-mimicking proteoglycan-modified surfaces provide information on the initial steps of lipoprotein-related plaque formation, which correlates with findings on endothelial cells and blood vessels, and afford insight into the role of lipoprotein deposition and exchange phenomena at the onset of these pathophysiologies.


Asunto(s)
Enfermedad de Alzheimer , Arteriosclerosis , Glucosa/química , Lipoproteínas/química , Enfermedad de Alzheimer/metabolismo , Animales , Arteriosclerosis/metabolismo , Calcio , Diabetes Mellitus Tipo 2 , Glucosa/metabolismo , Humanos , Lipoproteínas/metabolismo
3.
J Nucl Med ; 40(8): 1246-51, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10450673

RESUMEN

UNLABELLED: Somatostatin receptor scintigraphy (SRS) using 111In-octreotide has proven useful in patients suspected of having meningiomas. Delayed imaging is regularly performed up to 24 h postinjection. However, this procedure is time consuming and expensive. Therefore, we investigated whether 24-h imaging may be omitted in these patients. METHODS: After clinical examination and standard MRI, 71 patients were suspected of having 92 meningioma lesions. Before surgery, all patients underwent SRS after intravenous injection of 200 MBq (5.4 mCi) 111In-octreotide. Planar whole-body images were obtained at 10 min and 1, 4 and 24 h, and SPECT was performed at 4 and 24 h. Results of SRS in all lesions were evaluated with respect to histology and time of image acquisition. RESULTS: SRS yielded 58 true-positive, 20 true-negative and 14 false-negative results, with the false-negatives all less than 5 mL (2.3+/-2.1 mL) in volume. In 52 of 58 true-positive lesions (89.7%), diagnosis could be established by 4-h imaging without further information by 24-h imaging. In 10 of the 52 lesions, SPECT was necessary to confirm planar findings. Imaging at 24 h was necessary in only 6 of 58 true-positive lesions (10.3%): 3 patients who had intracranial relapse of meningioma (volume < 5 mL) and 3 who had spinal meningioma. Thus, a diagnosis of intracranial meningioma could be established in 52 of 55 lesions (95%) using a 4-h imaging protocol. CONCLUSION: With a 4-h acquisition protocol that includes SPECT imaging, SRS yields sufficient information in patients suspected of having intracranial meningiomas. Delayed imaging at 24 h is recommended only for patients who have small meningiomas (volume < 5 mL), spinal localizations or negative SRS at 4 h.


Asunto(s)
Neoplasias Meníngeas/diagnóstico por imagen , Meningioma/diagnóstico por imagen , Receptores de Somatostatina/análisis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Reacciones Falso Positivas , Femenino , Humanos , Radioisótopos de Indio , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Octreótido , Radiofármacos , Factores de Tiempo , Tomografía Computarizada de Emisión de Fotón Único
4.
J Nucl Med ; 39(11): 1913-7, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9829583

RESUMEN

UNLABELLED: Surgery is the treatment of choice in patients with meningioma. However, the risk of postoperative, local recurrence is well-known since total resection is not always feasible. Moreover, in these patients MRI may fail to differentiate between tumor remnants, recurrent meningioma or nonspecific hyperperfusion. In this study, the value of functional imaging using somatostatin receptor scintigraphy (SRS) was evaluated in postsurgical follow-up. METHODS: Before and 2-3 mo after surgery, 27 patients with meningioma received MRI as well as SRS after intravenous injection of 200 MBq 111In-octreotide. Planar whole-body images were obtained at 10 min, 1, 4 and 24 hr postinjection, and SPECT was performed at 4 and 24 hr postinjection. The final diagnosis was proven histologically in all patients. RESULTS: Before surgery, MRI showed focal contrast enhancement in all patients, and SRS revealed focal accumulation of 111In-octreotide. Thus, MRI and SRS yielded comparable results in all 27 patients. After surgery, MRI showed diffuse contrast enhancement in the area of the primary tumor site in all patients. Thus, MRI did not allow a differentiation between tumor and nonspecific hyperperfusion. In contrast, SRS revealed focal accumulation of 111In-octreotide in 16 of 27 patients indicating remaining tumor tissue or relapse of meningioma. This resulted either in an operative revision or in more frequent postsurgical follow-up examinations. In 11 of 27 patients, SRS was negative. Thus, total resection of meningioma was assumed, and no further interventions were performed. CONCLUSION: Functional imaging using SRS is a highly specific imaging modality and has a significant impact in postsurgical follow-up in patients with meningioma.


Asunto(s)
Hormonas , Radioisótopos de Indio , Neoplasias Meníngeas/diagnóstico por imagen , Meningioma/diagnóstico por imagen , Octreótido , Receptores de Somatostatina/análisis , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias Meníngeas/patología , Neoplasias Meníngeas/cirugía , Meningioma/patología , Meningioma/cirugía , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasia Residual , Cuidados Posoperatorios , Factores de Tiempo , Tomografía Computarizada de Emisión de Fotón Único
5.
Med Sci Sports Exerc ; 16(3): 316-21, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6748932

RESUMEN

The present experiment determined the validity of arm radiography for quantifying total body fat in young and older men and women. One hundred subjects were measured for 1) body density by underwater weighing with correction for residual air volume to estimate percent body fat and 2) horizontal right upper arm x-ray at KV 76, exposure time 1/30th s, 300 MA, and focal length 72 inches. Total radiation was 10 millirems (mR). The width of fat on the x-ray was measured at three cross-sectional sites (FAT,x-ray). Errors of measurement and measurement for reliability were assessed from duplicate x-rays and repeated measures on the same x-rays (r = 0.92-0.99). The equation to convert FAT,x-ray to individual estimates of percent fat is %Fat = FAT,x-ray/3F X k constant, where 3F = 3 square root wt,kg/ht,dm, and the k constant is a previously determined mean value. The correlation between Fat,x-ray and percent fat (density) was r = 0.89 (N = 100, Se = +/- 2.54); for 25 young men (ages 18-30), r = 0.90 (Se = +/- 1.84); for 25 older men (ages 30-40), r = 0.89 (Se = +/- 2.20); for young (N = 25) and older (N = 25) women, r = 0.85 (Se = +/- 2.08) and 0.87 (Se = +/- 2.61), respectively. These results demonstrate that the new, arm radiogrammetric method is a reliable and valid technique for assessment of body composition in men and women ages 18-40 yr.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Tejido Adiposo , Brazo/diagnóstico por imagen , Peso Corporal , Adolescente , Adulto , Femenino , Humanos , Masculino , Radiografía , Factores Sexuales
6.
JPEN J Parenter Enteral Nutr ; 2(4): 532-53, 1978 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-569722

RESUMEN

Elementary anthropometric and radiographic techniques, carefully executed and routinely employed in definitive surveys of healthy persons, are of potential value in assessment of patients, and provide the following: 1. Formulas to compute mean "ideal body weights" of young adults from stature (W = kh1.7). 2. A "unit size-weight" index (uS-W) with a mean value of 100 or nearly identical to 100 for all mean "ideal weights" relative to stature. 3. The distribution of values of the uS-W index for 80 and 90% of the population of young adults around the mean. 4. Conversion of body girths and stature to ponderal equivalents such that component A reflects fatness (if present) and component B, leanness and muscularity. 5. Conversion of skeletal diameters and stature to a relative "frame" size weight, designated component C, and employed as a "reference weight" (Ref W) for the calculation of lean body weight (LBW) in the male, and "minimal weight" as well as LBW in the female. 6. Conversion of skinfold thickness to estimates of body fat by means of a surface area formulation where: Weight of fat = SA x skinfold widths x k(fat). 7. The introduction of comprehensive arm radiography to reveal presumptive estimates of body fat from SA and of the amount of bone and muscle in the arm to LBW. 8. The visualization of body shape in the somatogram, and the value of photography under strictly controlled conditions.


Asunto(s)
Antropometría/métodos , Brazo/diagnóstico por imagen , Fenómenos Fisiológicos de la Nutrición , Adolescente , Adulto , Anciano , Brazo/anatomía & histología , Estatura , Peso Corporal , Niño , Preescolar , Femenino , Humanos , Masculino , Matemática , Persona de Mediana Edad , Radiografía
7.
Nucl Med Commun ; 17(4): 302-10, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8786866

RESUMEN

The aim of this study was to evaluate somatostatin receptor scintigraphy (SRS) in patients with meningioma proven or suspected on magnetic resonance imaging (MRI). Prior to surgery, 47 patients were investigated up to 24 h following the injection of 200 MBq 111In-octreotide. Tracer uptake was compared with the histological presence of meningioma. Histology revealed 43 meningiomas, 3 neurinomas and 1 ependymoma. A true-positive SRS result was obtained in 36 patients, in 13 of whom a tumour volume of < 10 ml was noted. A false-negative SRS result was obtained in seven patients, all of whom had a tumour volume of < 10 ml. Whereas MRI alone was decisive in 38 of 47 patients, it could only provide a differential diagnosis in the remaining 9 patients. A positive SRS result confirmed meningioma in five of these patients, and a negative SRS result excluded meningioma in the other four. Therefore, cases of SRS-negative meningioma do exist. Nevertheless, significant clinical benefit can be obtained from functional imaging with 111In-octreotide in patients with an inconclusive MRI result, as large meningiomas can be excluded by scintigraphy alone, whereas meningiomas of any size may be confirmed in combination with specific MRI results.


Asunto(s)
Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/metabolismo , Meningioma/diagnóstico por imagen , Meningioma/metabolismo , Receptores de Somatostatina/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Ependimoma/diagnóstico , Ependimoma/diagnóstico por imagen , Ependimoma/metabolismo , Reacciones Falso Negativas , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Persona de Mediana Edad , Neurilemoma/diagnóstico , Neurilemoma/diagnóstico por imagen , Neurilemoma/metabolismo , Octreótido/análogos & derivados , Cintigrafía
8.
Aviat Space Environ Med ; 46(4 Sec 2): 514-20, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1156267

RESUMEN

Tests were carried out on pocket mice to ascertain their tolerance to elevated oxygen pressures alone and to a combination of hyperoxta and heat in excess of that expected during the flight of the mice on Apollo XVII. the mice withstood oxygen partial pressures up to 12 pst at normal room temperature (24 degrees C, 75 degrees F) over a period of 7 days. A few mice previously exposed to increased PO2 died in the course of exposure to an oxygen pressure of 10 pst or 12 psi (517 mm or 620 mm Hg) for 13 d in ambient heat of 32 degrees C (90 degrees F). Supplemental vitamin E and physiological saline loading given prior to exposure had no apparent protective effect. The overall conclusion was that the pocket mice which were to go on Apollo XVII could readily survive the ambient atmosphere to which they would be exposed.


Asunto(s)
Adaptación Fisiológica , Radiación Cósmica , Calor , Oxígeno , Efectos de la Radiación , Vuelo Espacial , Animales , Cámaras de Exposición Atmosférica , Presión Atmosférica , Ambiente Controlado , Ratones , Presión Parcial , Cloruro de Sodio/administración & dosificación , Estados Unidos , Vitamina E/farmacología
9.
Aviat Space Environ Med ; 46(4 Sec 2): 500-13, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-239672

RESUMEN

A closed passive system independent of support from the spacecraft or its crew was developed to house five pocket mice for their flight on Apollo XVII. The reaction of potassium superoxide with carbon dioxide and water vapor to produce oxygen provided a habitable atmosphere within the experiment package. The performance of the system and the ability of the mice to survive the key preflight tests gave reasonable assurance that to mice would also withstand the Apollo flight.


Asunto(s)
Radiación Cósmica , Sistemas Ecológicos Cerrados/instrumentación , Sistemas de Manutención de la Vida/instrumentación , Efectos de la Radiación , Vuelo Espacial , Animales , Atmósfera , Conducta Animal , Dióxido de Carbono , Oído Medio/patología , Ambiente Controlado , Conducta Alimentaria , Gravitación , Hemorragia/epidemiología , Pulmón/patología , Ratones , Oxígeno , Potasio , Superóxidos , Estados Unidos , Ingravidez
10.
Aviat Space Environ Med ; 46(4 Sec 2): 529-36, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1156271

RESUMEN

The final phase to fly five pocket mice in the Apollo XVII command module was carried out at the NASA Kennedy Space Center. Upon completion of the 13-d space flight, the package was removed from the spacecraft and, after having been purged with an oxygen-helium gas mixture, was flown to American Samo. Four of the five mice were recovered alive from the package. Analysis of the mouse that died during the flight revealed several factors that could have contributed to its death, the chief of which was massive hemorrhage in its middle ear cavities.


Asunto(s)
Radiación Cósmica , Efectos de la Radiación , Vuelo Espacial , Animales , Conducta Animal , Encéfalo/patología , Enfermedades del Oído/patología , Oído Medio/patología , Femenino , Hemorragia/patología , Sistemas de Manutención de la Vida/instrumentación , Masculino , Ratones , Estados Unidos
11.
Aviat Space Environ Med ; 46(4 Sec 2): 582-606, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1156275

RESUMEN

In the five pocket mice flown on Apollo XVII, no evidence was found that the inner ear had been damaged, though poor fixation precluded detailed study. On the other hand, the middle ear cavity was involved in all the mice, hemorrhage having occurrred in response to excursions in pressure within the canister that housed the mice during their flight. The same occurred in flight control mice which had been subjected to pressure excursions of much the same magnitude. A greater degree of exudation into air cells and greater leukotaxis were noted in the flight animals than in the control animals. There was no increase in leukocyte population along the paths of the 23 cosmic ray particles registered in the subscalp dosimeters that traversed the middle ear cavities of the flight mice. The increased exudation and the greater response by leukocytes in the flight mice may have been causally related to the lesions found in their olfactory mucosa but there were no data in support of this possibility.


Asunto(s)
Radiación Cósmica , Oído Medio/efectos de la radiación , Efectos de la Radiación , Vuelo Espacial , Animales , Presión Atmosférica , Agregación Celular , Enfermedades del Oído/patología , Oído Medio/anatomía & histología , Oído Medio/patología , Exudados y Transudados , Hemorragia/patología , Leucocitos , Ratones , Óxidos , Oxígeno , Potasio , Estados Unidos
12.
Aviat Space Environ Med ; 46(4 Sec 2): 561-81, 1975 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1156274

RESUMEN

The olfactory epithelium, but not the nasal respiratory epithelium, of the four pocket mice (Perognathus longimembris) that survived their flight on Apollo XVII showed both diffuse alterations and numerous disseminated focal lesions. The olfactory mucosa of the mouse that died during flight was also affected, but to a minor degree insofar as could be determined. All this was in contrast to the normal appearance of the olfactory mucosa of the numerous control animals. A number of possible causes were considered: systemic or regional infection; inhaled particulate material (seed dust); by-products from the KO2 bed in aerosol or particulate form; gas contaminants originating in the flight package; volatile substances from the dead mouse; weightlessness; and cosmic ray particle radiation. Where feasible, studies were conducted in an effort to rule in or rule out some of these potentially causative factors. No definitive conclusions were reached as to the cause of the lesions in the flight mice.


Asunto(s)
Radiación Cósmica , Mucosa Nasal/efectos de la radiación , Efectos de la Radiación , Vuelo Espacial , Aerosoles , Animales , Polvo , Contaminantes Ambientales , Infecciones , Ratones , Mucosa Nasal/anatomía & histología , Mucosa Nasal/patología , Potasio , Monitoreo de Radiación , Semillas , Estados Unidos
16.
Artículo en Inglés | MEDLINE | ID: mdl-19680986

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs), which are generated by heat treatment and smoke curing of meat, pose a risk to human health. At present, the determination of these unwanted contaminants requires costly, time-consuming chemical analysis of smoked meat. An alternative is effect-directed high-throughput bioassays, which could also be used as a pre-screening method. The authors recently adapted the in vitro chemical-activated luciferase gene expression (CALUX) assay as a rapid, sensitive, and inexpensive screening technique for compounds such as dioxins, polychlorinated biphenyls, and PAHs. The aim of the present study was to apply a practical approach under realistic conditions. Custom-made meat samples produced under defined conditions with different PAH levels were analysed using this bioassay and gas chromatography-mass spectrometry (GC/MS) to determine the influence of different smoking conditions (temperature and duration) on PAH levels. It was found that cold smoking for up to 6 h did not result in strong PAH contamination, whereas hot (65 degrees C) and longer smoking times caused a considerable increase in both the bioassay response and the levels of 31 individually determined PAHs. The response in the effect-based bioassay was in good agreement with the values of chemical analysis. The bioassay made it possible to determine accurately the degree of contamination. The results show that this assay is suitable for high-throughput screening for unknown levels of toxicologically relevant PAHs in meat samples and is sensitive enough to differentiate between different PAH levels generated under various smoking conditions. Effect-based screening techniques, therefore, provide a new instrument for official food monitoring.


Asunto(s)
Carne/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Animales , Manipulación de Alimentos/métodos , Conservación de Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Porcinos
17.
Undersea Biomed Res ; 6(4): 357-65, 1979 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-538864

RESUMEN

A square-root formulation, square-root time x excursion depth = k, developed at the Royal Navy Physiologic Laboratory (RNPL) predicts the safe duration of air excursions at 1 ATA for periods up to 6 h (air) and up to 3 h (heliox atmosphere). At pressures above 1 ATA, the value of k was initially considered to be proportional to Haldanian multiples of ATA and not to the square-root ATA used in this paper. Excursions of infinite (infinity) duration can also be predicted from a square-root formula derived from the systematic heliox saturation excursions conducted at the Experimental Diving Unit in which net excursion depth = k square-root P abs. This paper presents a broad spectrum format that extends the square-root principle: 1) to values of k above 1 ATA in the RNPL formula and 2) to excursions for (infinity) time from habitat depths to 820 ft; and 3) which demonstrates a relationship between fractional time excursions and excursions for infinite periods of time. Application of the generalization that net excursion depths are proportional to square-root P abs would reduce to a minimum the number of programmed test dives and would, in addition, allow such dives to be conducted at relatively low pressures, with only occasional validating tests at deep depths.


Asunto(s)
Presión Atmosférica , Buceo , Helio , Humanos , Matemática , Oxígeno
18.
Neurosurg Rev ; 23(1): 25-9, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10809483

RESUMEN

With life expectancy in the industrial nations increasing during recent years, the number of patients older than 70 years with intracranial tumours and, especially, meningiomas is rising. To evaluate the indications for operative treatment, we reviewed 66 patients older than 70 years who were operated upon for intracranial meningioma in our department between 1991 and 1997. The mean age was 75 years. The oldest patients were 86 years old. Thirteen patients with recurrent meningiomas were operated upon. The mortality rate was 7.6%. Neurological symptoms improved in 38 patients (57.6%), were unchanged in 11 (16.6%), and deteriorated in 12 (18.2%). Patients with recurrent meningiomas seem to have a higher operative risk and their outcome is worse than after a primary operation. In general, there were good postoperative results in patients with few concomitant diseases, small meningiomas, small edema, short time of operation, and accessible location (convexity rather than skull base). Age in general is not a contraindication for operation. In cases of incidental findings of small meningiomas, we recommend observation and MRI follow-up. Symptomatic meningiomas should be removed whenever there is an acceptable risk from an internal or anaesthesiological point of view.


Asunto(s)
Meningioma/cirugía , Procedimientos Neuroquirúrgicos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Meningioma/diagnóstico por imagen , Meningioma/patología , Recurrencia Local de Neoplasia , Cintigrafía , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
19.
Zentralbl Neurochir ; 57(2): 108-12, 1996.
Artículo en Alemán | MEDLINE | ID: mdl-8779269

RESUMEN

Two hundred seventy-three Patients with acute SAH were treated within the last 46 months (1.4.1991 to 31.1.1995). Diagnosis was made upon visible SAH on CT-scans or bloody spinal tap regardless of a negative CT-scan. These patients harbored 194 aneurysms, 25 AVM and cavernomas. Within the same time-period we treated 27 Patients without SAH but harboring vascular malformations (17 aneurysms, 10 AVM and cavernomas). In 30 patients (11%) no bleeding source was detectable. Fourteen of these patients (5.1%) had blood concentrated within the perimesencephalic cisterns on the CT-scans. On admission all of these 14 patients (8 men, 6 female, aged 30 to 63 years) were awake and without mentionable neurological deficit, equalling Hunt & Hess grade 1 (11 patients) and 2 (3 patients). Neither the initial nor control angiography revealed a vascular malformation as a bleeding source. MRI-scans performed for 11 patients did not reveal further etiological clues. During a follow-up interval of 3 to 48 months, none of these patients suffered a rebleeding. Vasospasm was not or only slightly present, no ischemia leading to neurological deficit. GOS reached 5 and Karnofsky-scale was 100 for all of these patients. We conclude that the perimesencephalic SAH is a homogeneous entity with a different natural course than the common aneurysmatic SAH. Probably leakage within the capillary or venous circulation causes this form of SAH with a benign clinical course. Further experience is required to determine whether control angiography is mandatory in these patents with a distinct CT appearance.


Asunto(s)
Mesencéfalo , Hemorragia Subaracnoidea/etiología , Adulto , Neoplasias Encefálicas/complicaciones , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Seno Cavernoso/patología , Diagnóstico Diferencial , Diagnóstico por Imagen , Femenino , Estudios de Seguimiento , Hemangioma/complicaciones , Hemangioma/diagnóstico , Hemangioma/terapia , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/diagnóstico , Aneurisma Intracraneal/terapia , Malformaciones Arteriovenosas Intracraneales/complicaciones , Malformaciones Arteriovenosas Intracraneales/diagnóstico , Malformaciones Arteriovenosas Intracraneales/terapia , Masculino , Mesencéfalo/patología , Persona de Mediana Edad , Examen Neurológico , Hemorragia Subaracnoidea/diagnóstico , Hemorragia Subaracnoidea/terapia
20.
Int J Sports Med ; 11(5): 349-56, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2262226

RESUMEN

There are conflicting results in prior studies concerning the relationships among body size, muscle size, and muscular strength. The purpose of the present study was to evaluate how body size, body shape, and segmental dimensions related to individual differences in muscular strength. Subjects were tested on four dynamic measures of strength and then classified into one of two groups as high strength (HS; N = 21) and low strength (LS; N = 21). Individual differences in strength were then related to body composition and segmental anthropometry. Strength was assessed during high-resistance, low-velocity standing squat and supine bench press with an isokinetic dynamometer, and during seated bench press and knee extension with a hydraulic resistance dynamometer. Anthropometry and body composition included 11 girths, six fatfolds, predicted fat-free mass (FFM), thigh and upper arm volume, muscle + bone cross-sectional area (CSA), and the Behnke Ponderal Somatogram (PSom) body profiling system. There was a 21.3% difference in strength between HS and LS (p less than 0.05), but no significant differences in age, stature, and fatfolds. MANOVA revealed that seven of 11 girth components of PSom were larger for HS (p less than 0.05). The correlations between strength vs body mass, FFM, thigh and upper arm volume, and CSA and fatfolds in HS and LS ranged from r = -0.52 to 0.56 (r = -0.70 to 0.70 when corrected for restriction of range). We conclude that individual differences in muscular strength are poorly related to various measures of body size and segmental body dimensions.


Asunto(s)
Composición Corporal , Constitución Corporal , Contracción Muscular , Adulto , Antropometría , Constitución Corporal/fisiología , Humanos , Masculino , Análisis Multivariante , Músculos/anatomía & histología , Músculos/fisiología
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