|
|
|
BRL Abstracts Database |
Your search for ultrasound produced 3296 results. Page 155 out of 330
Title |
Intense ultrasound - a new tool for neurological research. |
Author |
Fry WJ. |
Journal |
J Ment Sci |
Volume |
|
Year |
1953 |
Abstract |
No abstract available. |
Title |
Intense ultrasound in investigations of the central nervous system. |
Author |
Fry WJ. |
Journal |
Adv Biol Med Phys |
Volume |
|
Year |
1958 |
Abstract |
No abstract available. |
Title |
Intensity determination of ultrasonic focused beams used in.ultrasonography in the case of gravid uterus. |
Author |
Etienne J, Filipczynski L, Firek A, Groniowski J, Kretowicz J, Lypacewicz G, Salkowski.J. |
Journal |
Ultrasound Med Biol |
Volume |
|
Year |
1976 |
Abstract |
The authors applied two absolute methods for the determination of the intensity of ultrasonic focused beams of 2(dot)5 MHz frequency used in ultrasonograph UG-4 for abdominal visualization: the electrodynamic and the capacitance methods. For the first method a special electrodynamic transducer was constructed which made it possible to measure the acoustic (particle) velocity in the focal point of the ultrasonic beam radiating into water. Hence the focal intensity could be determined. The two methods gave almost the same intensity values equal to 23 W/cm2 in peak, (~23mW/cm(^2) time average value) although the mean surface value near to the radiating transducer was equal only to 0(dot)59 W/cm(^2) in peak (~0(dot)59 mW/cm(^2) time average value). Next, the loss of the ultrasonic signal was measured in pregnant women in vivo using for this purpose steel balls as reflecting targets placed in the gravid uterus. The echo amplitudes obtained in the uterus were compared with echoes received from the same steel balls placed in (nonabsorbing) water in the same position relative to the radiating transducer. In this manner it could be found that intensity levels inside of the uterus were 6-14 dB lower than at the body surface, depending on the anatomical characteristics of the patient. Thus the maximum (focal) intensities which are to be expected in the gravid uterus in early pregnancy will be between 0(dot)9 and 5(dot)5 W/cm(^2) in peak (0(dot)9-5(dot)5 mW/cm(^2) time average values) when applying the ultrasonograph UG-4. |
Title |
Intensiver ultraschall, ein werkzeug der neurologie. |
Author |
Fry WJ. |
Journal |
Int Rundschau Phys Med |
Volume |
|
Year |
1958 |
Abstract |
The more important aspects of the selective action of intense ultrasound on the tissue components of the central nervous system are briefly reviewed in this paper. The results of an extensive histological study of lesions, produced by a variety of different dosage conditions, are briefly summarized and the macroscopic appearance and accuracy of placement of ?selective? ultrasonic lesions are illustrated by photographs of stained tissue sections. The selective sparing of the vascular system and the differential susceptibility to the action of the sound, of white matter as contrasted with gray matter, are described. The present status of investigations of the physical mechanism of the action of the sound on the tissue is indicated. Reference is made, in this connection, to experiments on cooled animals, in which it has been shown that the increased temperature, resulting from the propagation of the intense ultrasound in the tissue, is not primary mechanism involved in the selective action. The instrumentation employed in precision ultrasonic irradiation research is briefly described and the technique of preparation and irradiation of the animal are also described. |
Title |
Interaction of intense ultrasound and the mammalian central nervous system. |
Author |
Dunn F, Fry FJ. |
Journal |
Proc Seventh Int Congr Acoust - Budapest |
Volume |
|
Year |
1971 |
Abstract |
No abstract available. |
Title |
Interaction of low intensity ultrasound and.ionizing radiation with the tumour cell.surface. |
Author |
Repacholi MH, Woodcock JP, Newman DL, Taylor KJ. |
Journal |
Phys Med Biol |
Volume |
|
Year |
1971 |
Abstract |
The effects of low intensity ultrasound and x-irradiation on the surface charge of tumour cells are described. Cell electrophoresis was used to detect any change in mobility of Ehrlich ascites-tumour cells exposed to both single and combined treatments of ultrasound and x-rays. Irradiation with ultrasound at 1 MHz frequency, with a peak intensity of 10 w cm(^2), pulsed 1:10 for 5 minutes, gave 15 % reduction in mobility; 1000 rads of 220 kV x-rays gave the same reduction, while combined treatments gave 30%. Possible mechanisms are discussed. |
Title |
Interaction of ultrasound and amniotic liquid. |
Author |
Zana R, Lang J. |
Journal |
Ultrasound Med Biol |
Volume |
|
Year |
1974 |
Abstract |
The ultrasonic properties (velocity at 2.81 and 5.04 MHz, absorption in the range 1-15 MHz and vibration potential at 200 kHz) of amniotic liquid have been investigated. The results indicate that at physiological pH the absorption is essentially due to the proteins found in amniotic liquid, its vibration potential to the sodium chloride contained in this fluid while the velocity appears to be determined both by the proteins and sodium chloride. In the acid range (pH ~ 3) and alkaline range (pH ~ 9.6), proton transfer processes involving a low molecular weight component of amniotic liquid, in addition to those involving the proteins, contribute to the absorption of ultrasound by amniotic liquid. |
Title |
Interaction of ultrasound and model membrane systems: Analyses and predictions. |
Author |
Tata DB, Dunn F. |
Journal |
J Phys Chem |
Volume |
|
Year |
1992 |
Abstract |
Low-intensity ultrasound (approximately 10(exp)(-6) W/cm2) in the frequency range 0.5-5.0 MHz was employed to investigate biomembrane structural relaxation kinetics via absorption and velocity dispersion spectroscopy. The multilamellar vesicles utilized in this investigation were composed of either pure phospholipids or mixtures of phospholipids and small molar fractions of protein gramicidin. The experimental findings reveal enhanced ultrasound interactions near the lipid phase transition temperature. The enhanced ultrasound absorption spectra closely resemble single-relaxation spectra, suggesting that the membrane constituents undergo a simple two-state transition. The temperature dependence of the relaxation frequency is followed with the combined aid of the absorption and velocity dispersion spectrum. Thermodynamic and electrical capacitor two-state transition models are developed to help describe the observed phenomena and to predict to a reasonable degree of accuracy the enhanced findings promoted by ultrasound. |
Title |
Interaction of ultrasound and tissue. |
Author |
Dunn F. |
Journal |
Proc First World Congr Ultrason Diagn Med SIDUO III - Vienna |
Volume |
|
Year |
1969 |
Abstract |
No abstract available. |
Title |
Interaction of ultrasound with neoplastic tissue. II. Systemic effects after local sonic irradiation. |
Author |
Longo FW, Tomashefsky P, Rivin BD, Longo WE, Lattimer JK, Willhite M, Tannenbaum M. |
Journal |
Urology |
Volume |
|
Year |
1976 |
Abstract |
Local sonic irradiation was applied to subcutaneously implanted Furth-Columbia rat Wilms' tumor. The weight and the rate of tritiated thymidine uptake were measured in host organs distal to the application field. Kidney and spleen weights were inhibited by the Wilms' tumor, and sonication of the tumor removed all or part of this inhibition. Liver weight was increased after sonication of tumor-bearing rats but not in nontumor-bearing rats. This may have been a response to tumor-specific substances released into the circulation by sonic destruction of tumor tissue. The adrenals enlarged as a response to the stresses of both tumor-bearing and of.sonication. Animals were implanted on both sides with the Wilms' tumor and on without any break in the growth curve while the sonicated right tumor was inhibited. These data suggest that the therapeutic effect of ultrasound is due solely to local factors and that systemic sequelae of some irradiation are unrelated to tumor inhibition. |
Page 1
| 2
| 3
| 4
| 5
| 6
| 7
| 8
| 9
| 10
| 11
| 12
| 13
| 14
| 15
| 16
| 17
| 18
| 19
| 20
| 21
| 22
| 23
| 24
| 25
| 26
| 27
| 28
| 29
| 30
| 31
| 32
| 33
| 34
| 35
| 36
| 37
| 38
| 39
| 40
| 41
| 42
| 43
| 44
| 45
| 46
| 47
| 48
| 49
| 50
| 51
| 52
| 53
| 54
| 55
| 56
| 57
| 58
| 59
| 60
| 61
| 62
| 63
| 64
| 65
| 66
| 67
| 68
| 69
| 70
| 71
| 72
| 73
| 74
| 75
| 76
| 77
| 78
| 79
| 80
| 81
| 82
| 83
| 84
| 85
| 86
| 87
| 88
| 89
| 90
| 91
| 92
| 93
| 94
| 95
| 96
| 97
| 98
| 99
| 100
| 101
| 102
| 103
| 104
| 105
| 106
| 107
| 108
| 109
| 110
| 111
| 112
| 113
| 114
| 115
| 116
| 117
| 118
| 119
| 120
| 121
| 122
| 123
| 124
| 125
| 126
| 127
| 128
| 129
| 130
| 131
| 132
| 133
| 134
| 135
| 136
| 137
| 138
| 139
| 140
| 141
| 142
| 143
| 144
| 145
| 146
| 147
| 148
| 149
| 150
| 151
| 152
| 153
| 154
| 155
| 156
| 157
| 158
| 159
| 160
| 161
| 162
| 163
| 164
| 165
| 166
| 167
| 168
| 169
| 170
| 171
| 172
| 173
| 174
| 175
| 176
| 177
| 178
| 179
| 180
| 181
| 182
| 183
| 184
| 185
| 186
| 187
| 188
| 189
| 190
| 191
| 192
| 193
| 194
| 195
| 196
| 197
| 198
| 199
| 200
| 201
| 202
| 203
| 204
| 205
| 206
| 207
| 208
| 209
| 210
| 211
| 212
| 213
| 214
| 215
| 216
| 217
| 218
| 219
| 220
| 221
| 222
| 223
| 224
| 225
| 226
| 227
| 228
| 229
| 230
| 231
| 232
| 233
| 234
| 235
| 236
| 237
| 238
| 239
| 240
| 241
| 242
| 243
| 244
| 245
| 246
| 247
| 248
| 249
| 250
| 251
| 252
| 253
| 254
| 255
| 256
| 257
| 258
| 259
| 260
| 261
| 262
| 263
| 264
| 265
| 266
| 267
| 268
| 269
| 270
| 271
| 272
| 273
| 274
| 275
| 276
| 277
| 278
| 279
| 280
| 281
| 282
| 283
| 284
| 285
| 286
| 287
| 288
| 289
| 290
| 291
| 292
| 293
| 294
| 295
| 296
| 297
| 298
| 299
| 300
| 301
| 302
| 303
| 304
| 305
| 306
| 307
| 308
| 309
| 310
| 311
| 312
| 313
| 314
| 315
| 316
| 317
| 318
| 319
| 320
| 321
| 322
| 323
| 324
| 325
| 326
| 327
| 328
| 329
| 330
|
|
|
|