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31.
32.
Cystic pancreatic tumors: CT and sonographic assessment 总被引:6,自引:0,他引:6
C D Johnson D H Stephens J W Charboneau H A Carpenter T J Welch 《AJR. American journal of roentgenology》1988,151(6):1133-1138
Thirty-five CT scans and 23 sonograms of 45 pathologically proved pancreatic cystic neoplasms (16 microcystic adenomas, 17 mucinous [macrocystic] cystadenomas, and 12 mucinous [macrocystic] cystadenocarcinomas) in 43 patients were retrospectively and blindly reviewed. Radiologic findings and their usefulness in differentiating microcystic from mucinous subtypes were assessed. The number of cysts within the tumors (more than six in microcystic adenomas and six or fewer in mucinous cystadenomas and cystadenocarcinomas) and the diameter of the majority of cysts within the tumor (less than or equal to 2 cm in microcystic adenomas and greater than 2 cm in mucinous tumors) were the most helpful radiologic findings in differentiating tumor types. Calcification was present in 38% of microcystic adenomas, 18% of mucinous cystadenomas, and 8% of mucinous cystadenocarcinomas by CT. Calcification was not definitely identified on any of the sonograms. A central scar was identified in only two (13%) of 16 microcystic adenomas. Blind retrospective review was often able to correctly classify tumors as either microcystic (CT, 93%; sonography, 78%) or mucinous (CT, 95%; sonography, 93%). All tumors with a typical appearance on either CT or sonography were categorized correctly. Cystic pancreatic tumors may be difficult to prospectively separate from other types of pancreatic cysts. Assuming a cystic neoplasm is present, it often can be classified correctly as microcystic or mucinous (macrocystic) by using the above criteria. 相似文献
33.
Research has demonstrated considerable heterogeneity in the long-term course of schizophrenia. In the period preceding the onset of frank psychosis (onset), patients vary relative to the rapidity of onset, the presence or absence of associality, and the presence or absence of semipsychotic symptoms. Following the onset of psychosis (middle course), patients may suffer from episodic or unremitting psychosis, and may or may not exhibit the deficit syndrome. In late adult life (late course), patients vary relative to the presence or absence of an improvement in psychosis and social capability. The usual approach to the study of putative course subtypes is to define a subtype by a number of features; they may include features of more than one epoch. In addition, the course of psychosis has not been distinguished from enduring personality impairments in these subtypes. Another approach to defining putative course subtypes would be based on dichotomizing patients according to the presence or absence of a particular feature of a single epoch. This second approach has important advantages: the availability of larger study populations and a diminished liability for confounding due to the correlates of features other than those under scrutiny. 相似文献
34.
R S Owen J P Carpenter R A Baum L J Perloff C Cope 《The New England journal of medicine》1992,326(24):1577-1581
BACKGROUND. Bypass grafting to arteries of the lower leg has become standard surgical management of advanced peripheral vascular disease. Its success depends on identifying suitable distal vessels. Preoperative preparation includes imaging of the arteries of the lower leg, usually by conventional contrast arteriography. An alternative procedure, magnetic resonance (MR) angiography, has been successfully employed in patients with various cardiovascular diseases, but its possible value in patients with peripheral vascular disease has received little attention. METHODS. We used both conventional and MR angiography in preoperative studies of the lower-leg vessels of 23 patients (25 legs) with peripheral arteriosclerosis and arterial insufficiency, and developed independent therapeutic plans based on the information provided by each technique. When the plans differed, the interventional procedure judged more likely to save the limb was performed. The findings of conventional and MR angiography were verified by intraoperative arteriography, postinterventional arteriography, or direct operative exploration. RESULTS. MR angiography detected all vessels identified by conventional angiography, whereas conventional arteriography failed to detect 22 percent of the runoff vessels identified by MR angiography. The detection by MR angiography of vessels not identified by conventional angiography altered the surgical management of the disorders of four patients (17 percent) and guided successful bypass procedures. CONCLUSIONS. MR angiography is a noninvasive technique with greater sensitivity than conventional contrast arteriography for detecting distal runoff vessels in patients with peripheral arterial occlusive disease. 相似文献
35.
超声引导下注射皮质类固醇治疗狭窄性腱鞘炎 总被引:1,自引:0,他引:1
目的 探讨超声引导下注射皮质类固醇治疗狭窄性腱鞘炎的方法及效果。方法 38例狭窄性腱鞘炎患者,按药物注射方法的不同随机分成2组。治疗组(21例)在10-MHz超声引导下向腱鞘内腱周间隙内穿刺注射醋酸强的松龙0.6 ml,对照组(17例)采用闭合穿刺法注射等量药物。注射前及随访时(注射后3周)测定疼痛强度视觉类比评分(Visual analogue score,VAS)。结果 随访时疼痛消失率治疗组为81%、对照组为53%,VAS下降值治疗组为[(6.8±1.9)x±s,下同]对照组为(5.1±3.0)。结论超声引导下将针尖穿刺于腱鞘内腱周间隙的操作简单、准确并可实时观察药物的分布,是治疗狭窄性腱鞘炎的较好方法。 相似文献
36.
We have examined the distribution of phospholipase C-gamma 1 (PLC-gamma 1) between membrane and cytosolic fractions in several cell lines. In MDA-468 cells, which are derived from a human breast tumor, greater than one-half of the total PLC-gamma 1 is associated with the membrane fraction of the cell. Unlike the situation in A-431 cells [G. Todderud, M. I. Wahl, S. G. Ree, and G. Carpenter, Science, 248: 296-298, 1990], epidermal growth factor (EGF) stimulation of MDA-468 cells does not result in significantly increased PLC-gamma 1 association with membranes. Immunoblot analysis reveals low levels of phosphotyrosine in PLC-gamma 1 and EGF receptors in unstimulated MDA-468 cells and greatly increased phosphotyrosine levels in these proteins as a result of EGF stimulation of the cells. We conclude that autocrine activation of EGF receptors is not responsible for the elevated association of PLC-gamma 1 with membranes in these cells. 相似文献
37.
L H Lin S Bock K Carpenter M Rose J J Norden 《Brain research. Molecular brain research》1992,14(1-2):147-153
Metabolic labeling and quantitative 2D gel autoradiography were used to assess changes in the synthesis and transport of GAP-43 in entorhinal cortex (EC) neurons and perforant pathway during lesion-induced sprouting and reactive synaptogenesis. In normal adult rats, there is a high constitutive level of GAP-43 synthesis and transport in EC neurons projecting to the hippocampus. Following unilateral EC lesions, there is a 2-fold (100%) increase in the transport of newly synthesized GAP-43 to the contralateral or 'sprouting' hippocampus. The timing of this upregulation (between 6 and 15 days) suggests that changes in GAP-43 expression occur in response to the growth of presynaptic terminals during sprouting. 相似文献
38.
The thesis of this article is that since followup studies of patients with schizophrenia have provided a rich body of informative knowledge, emphasis should now be on hypothesis testing in future studies. The consumer of research needs to have a general appreciation of statistical thinking, design, and methods to make an informed synthesis of results presented. This article presents a brief discussion of relevant statistics and statistical issues, as free of jargon as possible. Given the multivariable nature of psychiatric research, the natural focus is on multivariate statistics. A strong background in statistics is not required to understand the methods described and how and why they might be applied. Reference material for more detailed discussions is provided. It is a truism to say that the highest quality scientific work is dependent on an intimate collaboration with the expert in statistics and the expert in clinical methods, and this merits repeating only because it is so often ignored. 相似文献
39.
To investigate the effects of training frequency and specificity of training on isolated lumbar extension strength, 72 men (age = 31 +/- 9 years) and 42 women (age = 28 +/- 9 years) were tested before and after 12 weeks of training. Each test involved the measurement of maximum voluntary isometric torque at 72 degrees, 60 degrees, 48 degrees, 36 degrees, 24 degrees, 12 degrees, and 0 degrees of lumbar flexion. After the pretraining tests, subjects were randomly stratified to groups that trained with variable resistance dynamic exercise every other week (1X/2 weeks, n = 19), once per week (1X/week, n = 22), twice per week (2X/week, n = 23) or three times per week (3X/week, n = 21); a group that trained isometrically once per week (n = 14); or a control group that did not train (n = 15). Analysis of covariance showed that all training groups improved their ability to generate isometric torque at each angle measured when compared with controls (P less than 0.05). There was no statistical difference in adjusted posttraining isometric torques among the groups that trained (P greater than 0.05), but dynamic training weight increased to a lesser extent (P less than 0.08) for the 1X/2 weeks group (26.6%) than for the groups that trained 1X/week, 2X/week, and 3X/week (37.2 to 41.4%). These data indicate that a training frequency as low as 1X/week provides an effective training stimulus for the development of lumbar extension strength. Improvements in strength noted after isometric training suggest that isometric exercise provides an effective alternative for developing lumbar strength. 相似文献
40.