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排序方式: 共有1572条查询结果,搜索用时 15 毫秒
1.
James I. Geller MD Joseph G. Pressey MD Malcolm A. Smith MD Rachel A. Kudgus PhD Mariana Cajaiba MD Joel M. Reid PhD David Hall PhD Donald A. Barkauskas PhD Stephen D. Voss MD Steve Y. Cho MD Stacey L. Berg MD Jeffrey S. Dome MD PhD Elizabeth Fox MD Brenda J. Weigel MD 《Cancer》2020,126(24):5303-5310
2.
Analysis and management of chronic testicular pain 总被引:3,自引:0,他引:3
A total of 45 patients was seen in consultation between May 1980 and April 1989 for chronic unilateral or bilateral orchialgia, defined as intermittent or constant testicular pain 3 months or longer in duration that significantly interferes with the daily activities of the patient so as to prompt him to seek medical attention. We analyzed 34 patients available for followup in terms of socioeconomic parameters, etiology and duration of pain, associated urological symptomatology, specific treatment and results of therapy. Of the patients 31 underwent surgical treatment after failing medical management (24 orchiectomies, 10 epididymectomies, 5 orchiopexies and 1 hydrocelectomy). Of 10 patients who underwent epididymectomy 9 underwent subsequent orchiectomy as definitive treatment. Of 15 patients who underwent inguinal orchiectomy 11 (73%) reported complete relief of pain, while 4 had partial relief. Of the 9 patients who underwent scrotal orchiectomy 5 (55%) reported complete relief of pain, 3 had partial relief and 1 denied improvement. On the basis of these results we recommend inguinal orchiectomy as the procedure of choice for the management of chronic testicular pain when conservative measures are unsuccessful. 相似文献
3.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
4.
To overcome specific absorption rate (SAR) limitations of spin-echo-based MR imaging techniques, especially at (ultra) high fields, rapid acquisition relaxation enhancement/TSE (turbo spin echo)/fast spin echo sequences in combination with constant or variable low flip angles such as hyperechoes and TRAPS (hyperTSE) have been introduced. Due to the multiple spin echo and stimulated echo pathways involved in the signal formation, the contrast behavior of such sequences depends on both T2 and T1 relaxation times. In this work, constant and various variable flip angle sequences were analyzed in a volunteer study. It is demonstrated that a single effective echo time parameter TE(eff) can be calculated that accurately describes the overall T2 weighted image contrast. TE(eff) can be determined by means of the extended phase graph concept and is practically independent of field strength. Using the described formalism, the contrast of any TSE sequence can be predicted. HyperTSE sequences are demonstrated to show a robust and well-defined T2 contrast allowing clinical routine MRI to be performed with SAR reductions of typically at least 70%. 相似文献
5.
Shigeru Ichioka MD ; Naomi Sekiya MT ; Masahiro Shibata PhD ; Takashi Nakatsuka MD 《Wound repair and regeneration》2007,15(4):572-576
The leukocyte-endothelium interaction is known to contribute to reperfusion injury, which is considered to participate in the pathophysiology of pressure ulcers, and integrin alphaV beta3 (alphavbeta3) has been shown to mediate the processes of cellular adhesion in various types of cells. This study aims to clarify leukocyte behavior in our original microcirculatory pressure-induced reperfusion model, which can visualize the microcirculation in vivo. We also estimated the effect of alphavbeta3 integrin inhibition on the reduction of the leukocyte-endothelium interaction. Mice with dorsal skinfold chambers were divided into three groups: the baseline group (n=6), in which animals received no compression; the compression-reperfusion group (n=6), in which animals underwent 2-hour compression of the dorsal skin, followed by release, and the inhibitor-treated group (n=7), in which an alphavbeta3 inhibitor, CP4715, was administered in addition to the compression-release procedure. Staining with rhodamine 6G quantitatively visualized leukocyte behavior under the intravital fluorescent microscope. Compression-reperfusion induced a significant increase in rolling, sticking, and extravasation of the leukocytes. Treatment with the inhibitor strikingly reduced leukocyte sticking and extravasation. The present experiment has provided evidence that alphavbeta3 inhibition reduces leukocyte-endothelium interaction in our original pressure-induced reperfusion model. 相似文献
6.
Dr. S. Eggstein MD G. Manthey MT T. Hirsch PhD F. Baas MA B. U. V. Specht MD E. H. Farthmann MD 《Digestive diseases and sciences》1996,41(6):1069-1075
Epidermal growth factor receptors (EGFR) andras mutations are known to play a significant role in controlling cell growth and tumor promotion. Both of them transmit mitogenic signals to the nucleus by activation of Raf-1 kinase. In this study, the expression of EGFR and mutant Ras proteins, and, for the first time, the expression, phosphorylation and kinase activity of Raf-1 kinase have been determined in paired samples of colorectal cancer and mucosa. The tumor and mucosa samples did not differ significantly with regard to Raf-1 kinase content and activity. A major difference between tumors and mucosa was found, however, in the phosphorylation of Raf-1. Most of the mucosa samples (13/20), but only 1/20 of the cancer samples, contained hyperphosphorylated Raf-1. EGFR were significantly (p=0.0025) decreased in the tumors. The decreased phosphorylation of Raf-1 in colonic carcinomas could be the result of activation of Raf-1 phosphatases or inactivation of kinases phosphorylating Raf-1. New forms of treatment based on EGFR overexpression do not seem to be suitable for the majority of colonic cancers.This work was supported by the state of Baden-Württemberg (Verbundforschungsprojekt: Aufklärung von Mechanismen der Tumorentstehung und Tumorabwehr). 相似文献
7.
Histomorphometric effects of calcium or calcium plus 25-hydroxyvitamin D3 therapy in senile osteoporosis 总被引:2,自引:0,他引:2
E S Orwoll M R McClung S K Oviatt R R Recker R M Weigel 《Journal of bone and mineral research》1989,4(1):81-88
To evaluate the effects of calcium and 25-OHD in the therapy of senile osteoporosis, we studied a group of 39 women aged 69 +/- 7 (standard deviation, SD) years with severe osteoporosis. The group was characterized histomorphometrically by depressed bone remodeling rates without hyperosteoidosis. No subject had risk factors for osteopenia other than their age and postmenopausal status, and no subject was receiving therapy for bone disease at the onset of the study. Subjects were followed for 2 years after randomization to receive either 1200 mg/day of calcium (as calcium carbonate) and 40 micrograms/day of 25-OHD (calcium-25-OHD group), or 1200 mg/day of calcium plus placebo (calcium-placebo group). Calcium-25-OHD resulted in a clear increase in 25-OHD levels (p less than 0.001) and an increase in calcium absorption as indicated by urinary calcium excretion. Nevertheless, there was no significant change in fasting serum calcium, phosphorus, alkaline phosphatase, PTH, or 1,25-(OH)2D in either group. Radial and phalangeal bone mineral content and trabecular bone volume in the biopsied patients remained stable in both groups over the 2 year period. Unexpectedly, repeat bone biopsies revealed a clear improvement in the rate of mineralization in both groups, presumably as a result of the calcium supplementation alone. In summary, calcium-placebo and calcium-25-OHD treatment were both associated with stable appendicular bone mineral content in women with senile osteopenia. The finding of an effect of calcium supplementation on the rate of mineralization indicates that relative calcium deficiency may impair the mineralization phase of remodeling.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
Analysis of ischemia-reperfusion injury in a microcirculatory model of pressure ulcers 总被引:2,自引:0,他引:2
Shinsaku Tsuji MD ; Shigeru Ichioka MD ; Naomi Sekiya MT ; Takashi Nakatsuka MD 《Wound repair and regeneration》2005,13(2):209-215
The aim of this study was to establish a pressure ulcer model that visualizes the microcirculation, and to examine the participation of ischemia-reperfusion injury in the pathophysiology of pressure ulcers. An original system composed of a new skin fold chamber and compression device allowed loading quantitative vertical stress to the skin. An intravital microscopic technique enabled direct visualization of the microcirculation in the physiological condition and in response to pressure application. To estimate the effect of ischemia-reperfusion injury, animals were divided into two groups: the compression-release group (n = 8), in which the animals received four cycles of compression-release which consisted of 2 hours of compression followed by 1 hour of pressure release; and the compression alone group (n = 8) in which the animals underwent continuous compression for 8 hours. Functional capillary density was quantified before the compression procedure and on day 1 (35 hours) after the first evaluation. The cyclic compression-release procedure significantly decreased functional capillary density as compared to continuous compression, indicating that in our experimental setting repetition of ischemia-reperfusion cycle more severely damaged the microcirculation than single prolonged ischemic insult. This finding supports the significant contribution of ischemia-reperfusion injury to the pathophysiology of pressure ulcers at the level of dynamic in vivo microcirculation. 相似文献
9.
Ethanol Feeding Causes Inactivation of Both State 1 and State 2 Rat Hepatic Asialoglycoprotein Receptors 总被引:1,自引:0,他引:1
Benita L. Tworek Janet A. Oka Carol A. Casey Paul H. Weigel 《Alcoholism, clinical and experimental research》1997,21(8):1429-1434
Previous studies have shown that ethanol feeding in rats causes inactivation and redistribution of ˜50% of the total asialoglycoprotein receptors (ASGPRs) in hepatocytes (Tworek et al., J. Biol. Chem. 271:2531, 1996), and that two equal populations of hepatic ASGPRs mediate ligand uptake and processing via two functionally different pathways (Weigel in Glycoconjugates: Composition, Structure and Function , Marcel Dekker, 1992, p. 421). The purpose of this study was to determine if ethanol feeding causes preferential inactivation of only one of these two ASGPR populations, which have been designated state 1 and state 2 ASGPRs. The state 2, but not state 1, ASGPRs are inactivated in isolated hepatocytes by a variety of drugs and inhibitors. State 2 ASGPRs can also be inactivated in permeable cells by ATP treatment and then reactivated by treatment with fatty acyl coenzyme As. In the present study, permeable cell assays for state 2 ASGPR inactivation and reactivation were used to assess whether hepatocytes from ethanol-fed rats contain inactive state 2 ASGPRs. The results show that preferential inactivation of one ASGPR population does not occur after ethanol feeding. That inactive ASGPRs could not be reactivated by treatment with palmitoyl-coenzyme A to a greater extent in ethanol-fed versus control cells indicates there is not a larger pool of inactivated state 2 ASGPRs in treated cells. We conclude that ethanol feeding causes equal inactivation of both state 1 and state 2 ASGPRs. Ethanol feeding may represent the first treatment found to inactivate state 1 ASGPRs. 相似文献
10.