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1.
We evaluated the usefulness of 99mTc-MIBI scintigraphy in primary lung cancer in comparison with 201Tl-chloride scintigraphy. METHODS: There were 45 patients with primary lung cancer. All patients underwent dual-isotope imaging with 201Tl-chloride and 99mTc-MIBI. Regions of interest were placed over the tumors (T) and contralateral normal lung tissue (N) on one coronal view in the SPECT, and T/N ratio and retention index were calculated. RESULTS: The positive rate was 98% in both the early and delayed images for 201Tl-chloride and 96% in the early and 89% in the delayed image for 99mTc-MIBI. Both early and delayed T/N ratios for 201Tl-chloride were higher than those for 99mTc-MIBI. There was no significant correlation between T/N ratio and histological type of tumor in both images. However, in both images, there was a tendency for the early and delayed ratios to increase as the tumor diameter became larger. The retention index of 201Tl-chloride was higher than that of 99mTc-MIBI. There were no significant differences in the retention index with respect to the histological type and tumor size. CONCLUSION: The results of this preliminary clinical study suggest that 99mTl-MIBI can depict primary lung cancer similar to 201Tl-chloride. However, T/N ratio and retention index of 99mTc-MIBI in the tumor areas are significantly lower compared with those of 201Tl-chloride.  相似文献   

2.
Myocardial perfusion SPECT using the prone position improves inferior wall counts and decreases motion problems as compared with the usual supine position. Nonetheless, it is not suitable for women. In addition, it is associated with artifactual anteroseptal defects and hot spots. METHODS: The right lateral (RL) position was evaluated instead of the prone position in 72 patients (26 women). RL imaging was performed immediately after the supine imaging during a routine 2-day 99mTc-sestamibi exercise protocol. The SPECT images were scored semiquantitatively by three physicians. Moreover, regional myocardial counts, as well as extent and severity of defects, were assessed by quantitative polar map analysis. RESULTS: All patients tolerated the RL position well and there was no significant patient movement in either position. Higher inferior myocardial counts per pixel were observed in the RL than in supine images. Inferior wall defects (especially mild ones) were more common in the supine than the RL images, whereas defects in other regions were not different. Quantitative analysis confirmed these findings. Analysis of 34 patients with recent coronary arteriography revealed an overall coronary artery disease (CAD) supine- and RL-imaging specificity of 50% and 75%, respectively, and the sensitivities of both were 93%. Right CAD sensitivity, specificity and normalcy rates for the supine position were 100%, 44% and 55%, whereas those of the RL position were 94%, 75% and 90%, respectively. CONCLUSION: The RL position improves CAD diagnostic accuracy, particularly right CAD, without significant artifacts in other myocardial regions. Unlike the prone position, the RL position is well tolerated by both women and men.  相似文献   

3.
BACKGROUND/AIMS: There is growing interest worldwide in primary liver cancer. The aim of this study was to describe the incidence of this cancer over a 20-year period in a well-defined French population. METHODS: Time trends by 4-year period were studied by sex, age group, place of residence, histological type and associated cirrhosis. Trends were also analysed using the age-period-cohort model. RESULTS: Primary liver cancer incidence in men increased from 7.5/100000 for the period 1976-79 to 10.2/100000 for the period 1992-95. The mean annual variation was +2.2%, (p<0.05). The increase in incidence was seen mainly in the 55-64 and 65-74 age groups and concerned hepatocellular carcinomas. In men, the increase in incidence rates with time was observed mainly in rural areas, whereas incidence rates in urban areas remained stable. The rise in incidence was due mostly to an increase in primary liver cancer with cirrhosis, in relation to a progressive increase in post-hepatitic cirrhosis and a recent increase in alcoholic cirrhosis. The estimated cumulative risk for the life span 30-74 years increased from 0.8% for the 1904-1908 cohort to 2.1% for the 1934-1938 cohort. There was no significant trend in female rates. CONCLUSIONS: In France, incidence rates for primary liver cancer are increasing in men, whilst they are remaining stable in women. Our data confirm the primary importance of alcohol in the aetiology of this cancer. Further studies are necessary to unravel the respective roles of alcohol and hepatitis C virus in the increasing incidence of primary liver cancer.  相似文献   

4.
5.
BACKGROUND: Tumor hypoxia could play a role in the response to radiation therapy. Few data are available on oxygen tension (pO2) measurements in head and neck tumors. METHODS: The KIMOC-6650 Histograph (Eppendorf, Hamburg, Germany) was used to measure the oxygenation status of normal tissues and head and neck tumors in 20 patients. RESULTS: The median pO2 for normal tissues was 43 mmHg with very low pO2 values (2.0 mmHg or less) recorded in two patients. Low median pO2 levels (10 mmHg or less) were recorded in 2 of 5 primary tumors and in 11 of 15 metastatic lymphadenopathies, with very low values in 11 nodes. The median pO2 in tumors was lower than that of normal tissues in 12 of 15 patients with comparative measurements. Oxygen tension was recorded in three nodes after an evaluation of tissue density (by computed tomographic scanner); in two nodes, the mean and median pO2 values were lower in the hypodense areas than in isodense areas. The data for N2 and N3 nodes showed significantly more values below 2.0 mmHg as nodal size increased (P < 10(-4), by chi-square test). No systematic decrease in pO2 was recorded from the periphery to the center of the tumors. CONCLUSIONS: Very low pO2 values, corresponding to radiobiologic hypoxia, were found in most of these tumors. The prognostic value of these pO2 measurements in regard to treatment response remains to be demonstrated.  相似文献   

6.
OBJECTIVE: Secondary intracranial hypertension has been linked to leukocytosis. We examined our data bank containing physiologic recordings and outcome data of severely head injured patients to investigate the relationship between delayed increases in intracranial pressure (ICP), defined as occurring after a 12-hr period of normal ICP values, and leukocytosis. DESIGN: A retrospective study of observational data. SETTING: Regional neurosurgical unit and intensive care unit. PATIENTS: Sixty-four patients suffered increased ICP >20 mm Hg. Thirty-five patients fulfilled selection criteria for delayed increases in ICP (group 1). Twenty-nine patients with increased ICP with no preceding or intervening periods of normal ICP were selected as a comparison group (group 2). MEASUREMENTS AND MAIN RESULTS: Comparison of 12-month outcome revealed that 11% of group 1 patients died, with 49% remaining severely disabled, in contrast to group 2, where 35% of patients died and 14% were left severely disabled (p = .021). The pattern of outcome was independent of monitoring time, or injury severity. Regression modeling was performed for prediction of delayed increase in ICP. Of 46 patients with an initial increase then decrease in leukocyte count in the first 48 hrs, 65% experienced delayed increases in ICP, as compared with 18% of the 11 patients without this pattern p = .01 1). CONCLUSIONS: Patients with delayed increases have a significantly different pattern of outcome. Change in leukocyte count from admission to day 2 is a significant predictor of such a delayed increase.  相似文献   

7.
The purpose of our study was to compare the results of planar and SPECT scintimammography for the detection of breast carcinoma. In addition, our goal was to determine whether SPECT reconstructed with filtered backprojection (FBP) or with iterative algorithms (ISA) can improve the sensitivity and specificity of planar scintimammography (SMM). METHODS: One hundred thirteen patients with suspicious physical examinations and/or mammography underwent planar lateral and anterior breast imaging as well as SPECT imaging after injection of 99mTc-sestamibi. We used a blind evaluation, both separately and combined, for planar SMM, ISA-SPECT and FBP-SPECT. Scintigraphic findings were correlated with the final histopathological diagnoses. RESULTS: The sensitivity of planar SMM was 80% with a specificity of 83%. All ISA-SPECT studies were of diagnostic quality, while FBP-SPECT was considered nondiagnostic in 14 that were excluded for statistical calculation. Sensitivity of ISA-SPECT and FBP-SPECT were 71% and 69%, respectively. Specificity was 70% for ISA-SPECT and 66% for FBP-SPECT. Combined planar SMM plus ISA-SPECT sensitivity was 85% (81% for planar SMM plus FBP-SPECT) with a specificity of 72%. Three carcinomas indeterminate on planar SMM were correctly identified by combined planar SMM plus ISA-SPECT. ISA-SPECT and FBP-SPECT provided additional information to planar SMM with respect to localization of sestamibi uptake, tumor extent, improved diagnostic certainty and detection of axillary nodes in 40 and 14 patients, respectively. CONCLUSION: ISA reconstruction is the preferable approach to SPECT data. Combined with planar SMM, ISA-SPECT can improve sensitivity. SPECT is useful in cases of indeterminate and positive planar SMM.  相似文献   

8.
Detoxification of cyclophosphamide is effected, in part, by hepatic class 1 aldehyde dehydrogenase (ALDH-1)-catalyzed oxidation of aldophosphamide, a pivotal aldehyde intermediate, to the nontoxic metabolite, carboxyphosphamide. This enzyme is found in erythrocytes as well. Detoxification of aldophosphamide may also be effected by enzymes, viz. certain aldo-keto reductases, that catalyze the reduction of aldophosphamide to alcophosphamide. Such enzymes are also found in erythrocytes. Not known at the onset of this investigation was whether the contribution of erythrocyte ALDH-1 and/or aldo-keto reductases to the overall systemic detoxification of circulating aldophosphamide is significant. Thus, NAD-linked oxidation and NADPH-linked reduction of aldophosphamide catalyzed by relevant erythrocyte enzymes were quantified. ALDH-1-catalyzed oxidation of aldophosphamide (160 microM) to carboxyphosphamide occurred at a mean (+/- SD) rate of 5.0 +/- 1.4 atmol/min/rbc (red blood cell). Aldo-keto reductase-catalyzed reduction of aldophosphamide (160 microM) to alcophosphamide occurred at a much slower rate, viz. 0.3 +/- 0.2 atmol/min/rbc. Thus, at a pharmacologically relevant concentration of aldophosphamide, viz. 1 microM, estimated aggregate erythrocyte ALDH-1-catalyzed aldophosphamide oxidation, viz. 2.0 micromol/min, was only about 3% of estimated aggregate hepatic enzyme-catalyzed aldophosphamide oxidation, viz. 72 micromol/min; however, this rate is greater than the estimated flow-limited rate of aldophosphamide delivery to the liver by the blood, viz. 1.5 micromol/min. These observations/considerations suggest an important in vivo role for erythrocyte ALDH-1 in systemic aldophosphamide detoxification. Erythrocyte ALDH-1-effected oxidation of other aldehydes to their corresponding acids, e.g. retinaldehyde to retinoic acid, may also be of pharmacological and/or physiological significance since a wide variety of aldehydes are known to be substrates for ALDH-1.  相似文献   

9.
Patients with locally advanced head and neck tumors were treated +/-amifostine (200 mg/m2, i.v.) before radiotherapy (5x 2 Gy, for 6 weeks). A significant decrease in side effects (p=0.034) using the oral assessment score and duration of mucositis (p=0.02) in the amifostine group was observed. Amifostine is feasible and effective, decreasing acute and late side effects in patients with head and neck tumors.  相似文献   

10.
11.
Episcleral venous pressure was measured by means of an air jet at different levels of occlusion of the measured vessel. This was repeated at different points in one branching venous plexus system. The results indicate that the most reliable estimate of the pressure is obtained at the pressure level at which the blood column becomes somewhat paler. Occlusion of the vessel causes a rise in venous pressure which may be considerable, especially in large veins.  相似文献   

12.
AIM: Investigation of the relationship between the pO2-status of primary tumors, their cervical neck node metastases and normal tissues in squamous cell carcinomas of the head and neck. PATIENTS AND METHODS: Pretreatment oxygenation of primary tumors, their neck node metastases and of the contralateral sternocleidomastoid muscle was assessed in 16 patients with histologically proven advanced squamous cell carcinomas of head and neck. Oxygenation was measured with a polarographic microelectrode system (Eppendorf-pO-Histograph). Using CT/MRT additionally the volume of the tumors was estimated. RESULTS: A highly significant correlation existed between the median pO2 of primary tumors and their neck node metastases and between the relative proportion of hypoxic values (< 5 mm Hg) of both anatomic sites (both p = 0.0001) (Figure 1). Primary tumors were not different from their neck node metastases, neither regarding the pO2 median values nor in view of the relative frequency of hypoxic values (Table 1). No correlation was found between the volume of primary tumors and the one of their neck node metastases. For volume of tumors and the oxygenation status no relationship was found as well. Significantly different was the median pO2 in the muscles from the one of the malignant tissues (p = 0.0004). CONCLUSION: The results suggest that for to estimate the oxygenation status of squanious cell carcinomas of the head and neck pO2 measurements of primary tumors and neck node metastases are equally sufficient.  相似文献   

13.
Radiolabeled antitumor antibodies hold promise for diagnostic imaging and therapy in oncology. The purpose of this study was to investigate the pharmacokinetics, clearances and possible differences of two dosage administrations of the 99mTc-labeled antiepidermal growth factor (EGF)-receptor antibody and to predict the best dose and schedule for future clinical evaluations of this radiopharmaceutical. METHODS: Nine patients (4 women, 5 men; mean age 46.4 +/- 14.0 yr) were administered 1-3 mg 99mTc-labeled anti-EGF-receptor antibody (a murine IgG2a isotype) by intravenous bolus infusion. After administration, blood samples were collected from 7 patients from an antecubital vein opposite to the injection side at intervals from 2 min to 24 hr after injection, and plasma samples were obtained for pharmacokinetic analysis. Appropriate plasma samples were examined for isotope clearance (i.e., microCi/ml at various intervals) and 99mTc complexation to plasma proteins by fast protein liquid chromatography (FPLC) analysis. Urine was collected from each patient at 3 hr intervals up to 24 hr after monoclonal antibody administration to monitor 99mTc clearance. Plasma time-activity curves were fitted to a two-compartment model using nonlinear least-squares regression analysis by the method of flexible polyhedrals. RESULTS: Plasma disappearance curves of 99mTc-labeled anti-EGF-receptor antibody were best fit by biexponential equation with a distribution half-life (t(1/2alpha)) of 0.137 +/- 0.076 hr (n = 7) and elimination half-life (t(1/2beta)) of 20.3 +/- 8.0 hr. Analysis of urine showed that activity clearance by this route amounted to 4.9% +/- 0.6% of the injected dose in 24 hr, and FPLC analysis showed no evidence of decomposition, only 6%-7% of 99mTc was in a low molecular weight species. CONCLUSION: Plasma pharmacokinetics and urine clearance indicate comparability in both doses. The pharmacokinetic properties of the 99mTc-labeled anti-EGF-receptor antibody were found to be dose-independent. These findings provide an initial characterization of the radiopharmaceutical disposition in patients and may be used as the basis for calculating a better estimate of biodistribution and dosimetry for patients who will receive 188Re-labeled anti-EGF-receptor antibody (MAb ior egf/r3) injection for radioimmunotherapy and warrants further controlled clinical trials to define the efficacy of the radiopharmaceutical.  相似文献   

14.
This summary of the practice parameters describes the assessment, differential diagnosis, and treatment of children, adolescents, and adults who present with symptoms of attention-deficit/hyperactivity disorder. The rationales for specific recommendations are based on a review of the scientific literature and clinical consensus which is contained in the complete document. Assessment includes clinical interviews with the child and parents and standardized rating scales from parent and teachers. Testing of intelligence and academic achievement is usually required. Comorbidity is common. The cornerstones of treatment are support and education of parents, appropriate school placement, and psychopharmacology. The primary medications are psychostimulants, but antidepressants and alpha-adrenergic agonists are used in special circumstances. Other treatments such as behavior modification, school consultation, family therapy, and group therapy address remaining symptoms.  相似文献   

15.
Bone loss is a major complication of primary hyperparathyroidism (PHPT), and it has significant implications in the treatment of this disease. Bone turnover was measured in patients with PHPT, using quantitative bone SPECT (QBS), to determine if the rate of bone loss could be predicted before a significant decrease in bone mass occurs. METHODS: Forty-six patients were included in the study. QBS and bone mineral density (BMD) of the lumbar spine (LS) and femoral neck (FN) were done at baseline. The percent deviation of QBS in patients with PHPT from the values in normal matched controls was calculated. BMD was measured again after a mean of 17.5 mo in 38 patients, and in 29 patients a repeat BMD study was done after a mean of 41.4 mo. The change in BMD in patients with high and normal QBS values was compared using the nonparametric Mann-Whitney test. Regression analysis tested the correlation between baseline QBS values and BMD changes over time. RESULTS: For the FN, there was a statistically significant difference in the BMD change between patients with high and normal QBS values for short-term follow-up (-2.82%+/-4.80% versus 1.45%+/-4.67%, p < 0.05) and for long-term follow-up (-3.53%+/-5.34% versus 0.92%+/-2.40, p < 0.02). There was a negative correlation in the FN, r=-0.48 between QBS values and the percentage of change in BMD. There was no significant difference between the percentage of change in BMD in the LS in patients with high and normal QBS values for either short- or long-term follow-up. CONCLUSION: The results of this study show that QBS can predict bone loss in the FN in patients with PHPT. QBS can thus indicate the need for surgery at an early stage of the disease to prevent bone loss.  相似文献   

16.
Functional maxillofacial rehabilitation following tumor ablation depends on many variables. These include the magnitude of hard or soft tissue defects, the use of adjunctive chemotherapy or radiation therapy, and the presence of underlying systemic disease. The physiologic effects of tumor ablation and radiation therapy on local tissues and grafted bone are discussed in this article in relation to the ultimate use of implant supported prostheses. Cases are presented to illustrate a variety of clinical situations.  相似文献   

17.
Estrogens have a beneficial effect on atherosclerosis and osteoporosis after menopause, but their exact mechanism of action is still unknown. The aim of the present study was to investigate the effects of estradiol and its metabolites catechol estrogens on arachidonic acid metabolism in vitro. Estradiol had no effect on arachidonic acid metabolism up to 33 microM in A23187-stimulated human whole blood. All catechol estrogens (2-hydroxyestradiol, 2-hydroxyestrone, 4-hydroxyestradiol and 4-hydroxyestrone) had similar kinds of actions on arachidonic acid metabolism, being over ten times more potent inhibitors of leukotriene synthesis (IC50 values 0.044-0.16 microM) than thromboxane (IC50 values 0.99-2.1 microM) and prostaglandin E2 synthesis (IC50 values 0.84-5.5 microM). It is suggested that some of the protective actions of estrogens--e.g., on atherosclerosis and osteoporosis--may be related to the inhibition of leukotriene synthesis by catechol estrogens.  相似文献   

18.
The effects of human and porcine insulins on the symptomatic, physiological, and counterregulatory hormonal responses to acute hypoglycaemia were compared in 40 patients with Type 1 diabetes, 20 of whom were newly diagnosed while 20 had been treated for between 5 and 20 years. In a double-blind, cross-over trial all patients were treated with human or porcine insulin, in random order, for two consecutive 3-month periods. At the end of each treatment period they were subjected to an acute episode of experimental hypoglycaemia induced by a continuous intravenous infusion (2.0 mU kg(-1)min(-1)) of the same insulin species. Haemodynamic, sweating, and tremor responses were measured during both studies, symptom scores were recorded and the arterialized plasma glucose thresholds for autonomic activation and the onset of subjective symptoms were identified. In all patients the glycaemic thresholds for the initiation of the autonomic physiological responses to hypoglycaemia and the onset of the symptomatic response were concurrent and did not differ with insulin species (plasma glucose 1.94 vs 1.96 mmol I(-1), human vs porcine studies). The onset, temporal pattern, nature, and magnitude of the physiological responses (sweating, heart rate, blood pressure, and tremor) during acute experimental hypoglycaemia were also identical with each insulin species. The magnitude and temporal pattern of the response of counterregulatory hormones (adrenaline, noradrenaline, glucagon, ACTH, and GH) to hypoglycaemia as induced by human and porcine insulins were indistinguishable, as were the total and individual scores of autonomic and neuroglycopenic symptoms. In conclusion, in patients who had newly diagnosed and intermediate duration (5-20 years) of diabetes, the symptomatic, physiological, and counterregulatory hormonal responses to acute insulin-induced hypoglycaemia did not differ between human and porcine insulins, and the plasma glucose thresholds at which the symptomatic and autonomic responses were initiated were identical with both insulin species. This study does not support the hypothesis that treatment with human insulin modifies the symptomatic, physiological, and counterregulatory hormonal responses to acute hypoglycaemia.  相似文献   

19.
In an attempt to define chromosomal alterations that are associated with the metastatic phenotype, we investigated a total of 29 metastasizing (pN+) and 19 non-metastasizing (pN0) head and neck squamous cell carcinomas by comparative genomic hybridization (CGH). The analysis indicated that the pN0 tumors carried preferentially overrepresentations of chromosomes 5p, 6p, and 7p and that the pN+ tumors were frequently characterized by deletions on chromosomes 7q, 10q, 11p, 11q, 15q, and 20p and overrepresentations of the chromosomes 19q and 20q. In particular, the use of difference histograms and statistical analysis indicated that the deletions on chromosomes 10q25-q26 and 11p13-p14 were highly significant for metastasizing carcinomas. The findings on chromosome 10q were supported by loss of heterozygosity analysis in the primary tumors and eight synchronous lymph node metastases using four microsatellite polymorphisms. The data suggest that distinct patterns of genetic lesions are responsible for the metastatic phenotype of head and neck squamous cell carcinomas.  相似文献   

20.
Technetium-99m tetrofosmin is a lipophilic phosphine used for myocardial perfusion imaging. Biodistribution studies have shown significant thyroid uptake of tetrofosmin and preliminary reports have suggested that tetrofosmin imaging may be of value in patients with thyroid cancer. In this study, tetrofosmin whole-body scintigraphy was performed in 35 patients with evidence of thyroid diseases. All patients underwent laboratory evaluation of thyroid function as well as 99mTc pertechnetate scan, thallium-201 (n=16) 99mTc-methoxyisobutylisonitrile (MIBI) (n=19) whole-body studies. Thyroid images were semi-quantitatively analysed by a 4-point score: 0=no significant uptake; 1=uptake increased as compared to background activity, but inferior to normal thyroid tissue; 2=uptake equal to normal thyroid tissue; 3=uptake superior to normal thyroid tissue. Pathology examinations were obtained. A total of 41 thyroid nodules were detected, of which 15 were goitre nodules, 13 adenomas and 13 malignant lesions. In goitre nodules, concordant results of tetrofosmin and pertechnetate uptake (score 1 or 0) were observed in the majority of lesions (87%). In function adenomas (n=10), both tetrofosmin uptake and pertechnetate uptake were score 3. In non-function adenomas (n=3), tetrofosmin uptake was score 3, while pertechnetate uptake was score 0. In six malignant lesions, tetrofosmin uptake was score 3, while pertechnetate uptake was score 0; in the other seven lesions, where a prevalence of goitre abnormalities was observed, results of tetrofosmin and pertechnetate uptake were similar (score 0 or 1). In seven (70%) of the ten patients with malignant nodules, whole-body tetrofosmin images showed increased abnormal uptake in a total of 28 extra-thyroid tumour sites, as subsequently confirmed by other techniques. When tetrofosmin images were compared to 201Tl and 99mTc-MIBI scans, concordant results were observed in all cases. In conclusion, tetrofosmin imaging may be particularly useful to characterize and stage patients with malignant thyroid nodules; it shows similar results to thallium but provides better image quality. Comparable findings were observed between tetrofosmin and MIBI studies. Thus, tetrofosmin may be an alternative to thallium and MIBI in the aforementioned patients.  相似文献   

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