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991.
992.
Between January 1982 and December 1986, 54 patients with squamous cell carcinoma of the supraglottic larynx were treated for cure with radiation therapy alone; all had a minimum 2-year follow-up. For 31 patients, high-quality pretreatment CT scans were available for review. Scans were retrospectively evaluated by a single radiologist for the percentage of preepiglottic space involvement by tumor, the percentage of paralaryngeal space involvement, and the total tumor volume in cubic centimeters (cc). Volume was measured using a computer digitizer for each CT slice showing tumor. Results showed a significant difference in local control for tumors less than 6 cc versus tumors greater than or equal to 6 cc (15/18 or 83% vs 6/13 or 46%; p = .038). This difference was independent of both T stage and primary site. For T3 lesions, there was a trend toward decreased local control with increasing percentage of preepiglottic space involvement (0-25% = 85% local control; greater than 25% = 60% local control; p = .384); in most cases, however, the amount of preepiglottic space involvement reflected tumor volume (0-25%, 8/12 or 67% of tumors were less than 6 cc; greater than 25%, 7/10 or 70% of tumors were greater than or equal to 6 cc). There was no clear association between degree of paraglottic space involvement and local control. Tumor volume did not correlate with complications of treatment. Because of the limited number of patients in the current study, conclusions should be considered preliminary. However, the data do suggest that pretreatment CT findings, particularly tumor volume, can predict the likelihood of local control with radiation therapy alone for squamous cell carcinoma of the supraglottic larynx.  相似文献   
993.
The present study was undertaken to determine whether the viscerotropic species, Leishmania infantum, endemic in Italy, could induce tumor necrosis factor alpha (TNF alpha) in murine macrophages. Genetically susceptible (Lshs) and resistant (Lshr) mice were used in the attempt to correlate TNF alpha production with the ability to control parasite growth and replication. Resident peritoneal macrophages of C3H/HeN, DBA/2, CBA (Lshr), C57BL/10 and BALB/c (Lshs) mice were infected in vitro with promastigotes at a parasite to cell ratio of 8:1. No significant differences in the percentages of infected peritoneal cells of Lshs versus Lshr mice were observed until 72 h of in vitro culture. On the contrary, Kupffer cells from Lshr mice inhibited Leishmania replication. Peritoneal macrophages of resistant mice produced significantly higher amounts of TNF alpha as compared to susceptible mice. TNF alpha production of both resistant and susceptible mice peaked at about 5 h after the challenge with the parasite. No TNF alpha was found in supernatants of infected Kupffer cells from all the strains tested. The ability of macrophages from susceptible or resistant mice strains to produce TNF alpha after challenge with Leishmania infantum does not seem related to their capacity to control parasite replication in vitro.  相似文献   
994.
Using an immunoradiometric assay, Cathepsin-D (Cath-D) concentrations were measured in the cytosol of 68 normal and neoplastic human ovarian tissues. Cath-D levels were higher in malignant tumours than in normal tissue samples (P less than 0.01) and benign tumours (P less than 0.01). In six out of seven cases, metastatic deposits showed Cath-D concentrations higher than the respective primary tumours. Using 12 of 17 pmols.mg-1 protein as cut-off levels, the Cath-D status (high or low) was not related to any pathological parameter. Moreover, no correlation was found between Cath-D levels and receptors for oestrogen, progesterone and epidermal growth factor. Our results indicate that ovarian tumours produce Cath-D. Further studies are needed to evaluate whether this protein could represent a prognostic factor for this neoplasia.  相似文献   
995.
A comparative evaluation of computed tomography and laryngography.   总被引:1,自引:0,他引:1  
A A Mancuso  W N Hanafee 《Radiology》1979,133(1):131-138
A prospective study of 66 patients was conducted to evaluate the relative merits of computed tomography (CT) and laryngography in the assessment of laryngeal disorders. CT complemented direct laryngoscopy and biopsy for treatment planning and was superior to both modalities for showing deep infiltration, invasion of cartilage, and extension to the soft tissues of the neck. The subglottic space can be studied adequately by CT, which could also be useful in diagnosis of lymph node metastases. Distortion of the thyroid cartilage can be shown by CT. CT was equal to or better than laryngography in approximately 90% of cases.  相似文献   
996.
A multicenter double-blind randomized study was designed to evaluate and compare the safety and diagnostic efficacy of gadopentetate dimeglumine (Gd-DTPA) (0.1 mmol/kg) against a saline placebo for use as an IV contrast agent for MR. The randomization code provided for a 2:1 ratio of Gd-DTPA and saline patients. Six investigators studied 88 patients with signs and symptoms of a cerebral lesion. Although safety data were complete in all 88 cases, only 83 had valid efficacy data (57 received Gd-DTPA, 26 placebo). Three patients were excluded from efficacy evaluation because of incomplete scans or scans with severe motion artifacts. Two patients were excluded for protocol variations (did not have a mass lesion). The protocol required that spin-echo MR images be acquired both before and after infusion at mode 1, 500/30/2 (TR/TE/excitations), and at a single-echo mode 2 sequence within a selected range, 1500-2000/56-90/2. Additional TEs could also be used at the discretion of each investigator. Efficacy was determined by comparing post- with preinjection images for relative degree of enhancement and improvement of diagnostic ability after injection, and by comparing these results with placebo results. Enhancement was reported in 43 (75%) of 57 Gd-DTPA patients and in none of the 26 placebo patients. Improvement of diagnostic ability was noted in 37 of 57 Gd-DTPA patients and in no placebo patients. Of 17 patients receiving Gd-DTPA for whom no diagnosis could be made before infusion, nine of 17 were diagnosed after infusion. By comparison, none of five patients not diagnosed before infusion of placebo could be diagnosed after infusion. Of 43 patients in whom lesion enhancement was observed after Gd-DTPA infusion, the diagnosis changed after infusion in 16 (37%) and the number of lesions detected after infusion increased in 10 (23%). Safety studies showed no clinically significant abnormal trends. Minor changes in blood pressure, pulse, and serum iron levels were noted in a higher percentage of Gd-DTPA patients. This study confirms that Gd-DTPA is an efficacious contrast agent for use with MR and that it exhibits excellent patient tolerance. Enhancement allows for a decisive diagnosis to be made in selected cases in which such capability had previously been lacking with unenhanced MR.  相似文献   
997.
Ipriflavone (IP) (7-isopropoxyisoflavone), a synthetic isoflavone derivative, is active in both inhibiting bone resorption and enhancing osteoblast function. This property suggested its clinical use in the treatment of involutional osteoporosis, and in the prevention of postmenopausal bone mass loss. Forty postmenopausal women with low bone mineral content were enrolled and randomly treated for 12 months with IP 600 mg/day or placebo (PL), according to a double-blind, parallel group design. All patients wee also given an oral calcium supplementation (1 g/day). Bone mineral density (BMD) was measured at the spine (L2–L4) by dual-energy X-ray absorptiometry. Bone metabolism markers (serum calcium, phosphate, osteocalcin, and alkaline phosphatase, and urinary calcium, phosphate, and hydroxyproline) were assessed at the same times. After 12 months, a reduction of BMD was evidenced in the PL-treated group, at both the spine (–2.2%, P<0.01 vs baseline) and the forearm (–1.2%). In the IP-treated group, an increase of BMD was obtained (+1.2%, P<0.01 vs placebo, at the spine; +3%, not significant, at the forearm). Bone markers were in the normal range for postmenopausal women; no statistically significant modificantions were observed during the treatment period. Three patients were withdrawn from the treatment in the IP-treated group, and two in the PL-treated group for gastrointestinal disturbances. In the other women, the tolerance of the drug was good and the complicance with the oral treatment was excellent.  相似文献   
998.
血清IL-2、sIL-2R在病毒性肝炎中的意义   总被引:1,自引:1,他引:0  
为评估血清白细胞介素-2(IL-2)及可溶性白细胞介素-2受体(sIL-2R)在病毒性肝炎中的意义.对39例急性肝炎(AH),57例慢性乙型肝炎(CHB)受试对象和健康献血员对照组,分别采用放射免疫测定法和双抗体夹心ELISA法检测其血清IL-2和sIL-2R,结果显示AH和CH-B,患者血清中IL-2水平分别为7.2±4.0ng/ml和7.3±5.2ng/ml,均明显低于对照组(P<0.01),而sIL-2R水平分别为417.5±165.1u/ml和402.8±136.1u/ml,均明显高于对照组(P<0.01)。因此,我们认为血清IL-2和sIL-2R水平与病毒性肝炎病人的免疫功能和临床经过相关。  相似文献   
999.
Quercetin (from 0.1 muM to 10 muM) produced a dose dependent inhibition of colony formation of cells from 4 primary ovarian tumors expressing type II estrogen binding sites (type II EBS).The combined effects of quercetin ( 10 muM) and hyperthermia (42-degrees-C) result in a significant synergistic action on three out of four tumors analyzed. Moreover, two other flavonoids tested, rutin and hesperidin, which do not bind to type II EBS, are ineffective in synergizing with hyperthermia. In conclusion our results suggest that hyperthermia could synergize the growth inhibitory activity of quercetin which is probably mediated by the flavonoid interaction with type II EBS.  相似文献   
1000.
The aim of this study was to assess the association of p53 status with primary cytoreduction, response to chemotherapy and outcome in stage III-IV primary ovarian cancer patients. Immunohistochemical analysis of p53 was performed on formalin-fixed, paraffin-embedded specimens from 168 primary ovarian carcinomas by using the DO-7 monoclonal antibody. p53 nuclear positivity was found in 84 out of 162 (52%) malignant tumours. A higher percentage of p53 nuclear positivity was observed in patients with advanced stage of disease than in stage I-II (57% vs 23% respectively; P = 0.0022) and in poorly differentiated versus well/moderately differentiated tumours (59% vs 32% respectively; P = 0.0038). The multivariate analysis aimed to investigate the association of FIGO stage, grade and p53 status with primary cytoreduction in 136 stage III-IV patients showed that stage IV disease may influence the possibility to perform primary cytoreduction in ovarian cancer patients. p53-positivity also maintained a trend to be associated with poor chance of cytoreduction. In patients who underwent pathologic assessment of response, cases who did not respond to chemotherapy were much more frequently p53-positive than p53-negative (86% vs 14% respectively; P = 0.012). Moreover, patients with stage III disease and < 2-cm residual tumour were more likely to respond to treatment. In multivariate analysis, FIGO stage and p53 expression were independently correlated with pathologic response to chemotherapy. Time to progression and survival rates were shown not to be different in p53-positive versus p53-negative patients.  相似文献   
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