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61.
62.
Rao  AK; Rao  VM; Willis  J; Beckett  C; Steiner  RM 《Radiology》1985,156(2):311-313
The effects of an ionic contrast agent, meglumine iothalamate (Conray-60), and two newer low-osmolality radiographic contrast media, sodium meglumine ioxaglate (Hexabrix) and iopamidol (B-15,000), on platelet aggregation and secretion responses were studied. All three agents inhibited platelet responses during stimulation with adenosine diphosphate (ADP), epinephrine, and collagen. Platelet function was inhibited by iothalamate at concentrations of 11 mg iodine/ml and above, and by the newer agents at concentrations above 30 mg iodine/ml. Addition of exogenous calcium decreased the iothalamate-induced inhibition of aggregation but did not improve dense granule secretion. There was no consistent effect of exogenous calcium on platelet inhibition by iopamidol and ioxaglate. These studies indicate that the newer agents inhibit platelet function less than iothalamate does, and that chelation of Ca2+ may not be the major mechanism of platelet inhibition by contrast agents.  相似文献   
63.
Treatment of patients with squamous cell carcinoma (SCC) of an unknown primary localized to the neck is still controversial, particularly regarding advanced disease. We reviewed 41 such patients treated with surgery and/or radiotherapy (RT) (n = 25) or with combined modality treatment including chemotherapy (CH) (n = 16). The male to female ratio was 28 to 13, and the median age was 58 years (range, 32 to 94 years). There were 27 (66%) patients with poorly differentiated SCC and 8 with moderately differentiated or well-differentiated cancer. Twenty-three (56%) patients had N3 disease, 16 (39%) had N2, and 2 had N1. The majority of N3 patients have been treated with CH and RT (n = 12) or with RT alone (n = 9). The combined CH-RT was well tolerated, with no life-threatening toxicity. The complete response (CR) to CH-RT was 81% (11 patients have no evidence of disease [NED] currently). The median survival time of this group was 37+ months. Of the 25 patients who had surgery and/or RT as their first planned treatment, 7 (28%) have NED currently. The median survival time of this group was 24 months. Patients with N3 disease who received CH had a higher CR rate and a longer survival time as compared with those treated with surgery and/or RT, despite a higher (N3) stage of disease. These findings warrant further investigation in randomized cooperative studies.  相似文献   
64.
Acquired maxillo-facial deformities and in particular those related to problems of facial expression are nevertheless influenced by certain hereditary factors, amongst which the constitutional type or the temperament of the individual play a major role. Morpho-psychology (L. Corman), or the art of relating physical details (especially the shape and characteristics of the face) with psychological state demonstrates correlations between the type of deformity and that of the temperament and explains them. After a brief review of the essential principles of morpho-psychology, the authors study a number of special morpho-psychological types presenting with a significant frequency maxillo-facial deformities, themselves special, and which for this reason they call "morpho-psychological types with a high orthodontic risk". They conclude that it would appear that insufficient importance is attributed at present to psychological factors in the aetiopathogenesis of dysmorphoses and feel that an overall approach to the deformed child is indispensable to progress in the specialty.  相似文献   
65.
An experiment was conducted to determine the effects of autogenic and ‘opposite autogenic’ verbal formulae upon electrodermal activity. In a between-subjects design, 15 unpracticed volunteers listened to and followed tape recorded imagery suggestions for relaxation and quietude, heaviness and warmth in the extremities, warmth in the central area of the body, coolness of the forehead, and calmness and regularity of breathing and circulation; 15 additional volunteers were exposed to opposite suggestions. Frequency of spontaneous GSRs, cumulative peak amplitude of spontaneous GSRs, and basal skin resistance levels were measured during 2 min epochs before and after the suggestions. Directionally appropriate changes occurred in all three electrodermal measures; these changes were significant for the two GSR measures and approached significance for the BSR measure. The autogenic suggestions produced greater and more reliable visceral effects than did the ‘opposite autogenic’ suggestions.  相似文献   
66.
Experiments are described which show that vernix caseosa has a mechanical barrier effect if it is deposited in an unbroken layer. Specific antibacterial properties were not detected in vernix. It is suggested that vernix is best left on a newborn infant because of its mechanical obstruction to bacterial passage.  相似文献   
67.
Patients with dilated stenoses and recanalized occlusions were evaluated to assess the initial and long-term results of percutaneous transluminal angioplasty (PTA) in the femoropopliteal artery. The follow-up period was at least 1 year. The initial success rate was 84% (128/164). The initial results were influenced by the radiologist's experience, catheter selection, and type of lesion. The 5- and 7-year cumulative patency rates were 70% and 60%. There was no difference in long-term patency between initially successful stenoses and short (less than 3 cm) occlusions. Both the morphology and location of the stenotic lesion influenced the long-term results. Although many factors influence the initial and long-term success rate, results of this study justify PTA in the femoropopliteal artery. Patients with localized stenoses and short occlusions are best suited for this treatment.  相似文献   
68.
Ho  PS; Yu  SW; Sether  LA; Wagner  M; Ho  KC; Haughton  VM 《Radiology》1988,169(1):87-91
Magnetic resonance (MR) imaging, correlated with anatomic sections, was used to characterize the progressive and regressive changes in the nucleus pulposus in neonates. The spines of five fetuses and five full-term infants between 16 and 40 weeks old were studied. In anatomic sections, the nucleus pulposus was sharply demarcated from the anulus fibrosus, Sharpey fibers were conspicuous, and a plate of primitive notochord was evident in the equator of the disk. On long repetition time (TR)/long echo time (TE) or long TR/short TE MR images, Sharpey fibers (low signal intensity) and notochord (low signal intensity) could be differentiated from the high-signal-intensity nucleus pulposus and anulus fibrosus. The major differences between the fetal and infant spines were the amount of notochord in the disk and ossification in the vertebral body.  相似文献   
69.
70.
The present study was performed to investigate the capability of gemcitabine and pemetrexed to synergistically interact with respect to cytotoxicity and apoptosis in T24 and J82 bladder cancer cells, and to establish a correlation between drug activity and gene expression of selected genes in tumour samples. The interaction between gemcitabine and pemetrexed was synergistic; indeed, pemetrexed favoured gemcitabine cytotoxicity by increasing cellular population in S-phase, reducing Akt phosphorylation as well as by inducing the expression of a major gemcitabine uptake system, the human equilibrative nucleoside transporter-1 (hENT1), and the key activating enzyme deoxycytidine kinase (dCK) in both cell lines. Bladder tumour specimens showed an heterogeneous gene expression pattern and patients with higher levels of dCK and hENT1 had better response. Moreover, human nucleoside concentrative transporter-1 was detectable only in 3/12 patients, two of whom presented a complete response to gemcitabine. These data provide evidence that the chemotherapeutic activity of the combination of gemcitabine and pemetrexed is synergistic against bladder cancer cells in vitro and that the assessment of the expression of genes involved in gemcitabine uptake and activation might be a possible determinant of bladder cancer response and may represent a new tool for treatment optimization.  相似文献   
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