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11.
12.
Ultrasound and more recently colour Doppler ultrasound has been successfully used in the diagnosis of lower limb venous occlusive disease. Colour Doppler ultrasound has shown promise in the diagnosis of calf vein thrombosis but to date there has been no prospective trial to specifically evaluate its potential. In view of this, we carried out a prospective trial of 50 patients comparing the accuracy of colour Doppler ultrasound with venography in the diagnosis of deep venous thrombosis both above and below knee but in particular with respect to the detection of calf vein clot. Of the 50 patients studied, 10 had only one imaging modality performed as there were eight venographic failures and two ultrasonic failures. Comparison was only thus possible in 40 cases. As in previous studies, colour Doppler ultrasound was shown to be accurate in the diagnosis of thrombosis within the femoro-popliteal veins and had a sensitivity and specificity of 100% respectively. With respect to calf vein lesions, there was one false negative scan using the ultrasonic technique giving a sensitivity of 95%, specificity of 100% and accuracy of 97.5%. We feel colour Doppler ultrasound can and should be used as a first line alternative to venography and can be employed for the exclusion of both above and below knee deep venous thrombosis. Venography should now be reserved for those patients who are unsuitable for ultrasound examination or who have an equivocal ultrasound scan.  相似文献   
13.
Mannich bases were synthesized and converted to the corresponding arylhydrazones. X-ray analysis of a ketone (1a) and a hydrazone (4d) revealed structural features of interest. All of the compounds showed cytotoxicity toward murine lymphocytic leukemia L1210 cells in the 4.9-25.0-microM range. The correlation coefficients generated by plotting the IC50 values (the concentrations of compounds that inhibit the growth of tumors by 50%) of some hydrazones against certain electronic, hydrophobic, and steric constants of the aryl substituents indicated only weak correlations. A few ketones and hydrazones displayed significant cytotoxicity to the WiDr human colon cancer cells, and these derivatives, especially the ketones, may serve as prototypes for future drug development. The KB tumor (a human epidermoid carcinoma of the nasopharynx) was somewhat refractory to selected compounds. In an in vitro assay conducted by the National Cancer Institute and involving approximately 53 tumor cell lines originating from eight neoplastic diseases, 65% of the compounds showed some selectivity toward one or more groups of cancers, principally leukemia, melanoma, and colon cancer. The bioevaluation of the ketones and hydrazones against the L1210, WiDr, and KB tumors, as well as evidence from proton nuclear magnetic resonance studies did not support the suggestion that hydrazones may be prodrugs of the corresponding ketones.  相似文献   
14.
Alkylating agents have been the major group of chemotherapeutic agents associated with an increased incidence of secondary leukemias. In ovarian cancer alkylating agents have resulted in a lesser, although still increased, risk of secondary malignancies. This paper reports two cases of ovarian cancer treated with cisplatin and doxorubicin (Adriamycin, Adria Laboratories, Columbus, OH), and the subsequent development of an acute nonlymphocytic leukemia and a preleukemia syndrome. This regimen does not contain alkylating agents, and has not been associated with leukemia in patients with ovarian cancer. In these two cases, abnormalities of chromosomes 5, 7, 11, and 17 are reported which have been shown to occur in therapy-related leukemia.  相似文献   
15.

Objective

To document perceived adherence to treatment (taking medications and performing exercises) in patients with juvenile idiopathic arthritis (JIA) over a 1‐year period and to identify related factors.

Methods

We surveyed parents of patients with JIA at the Montreal Children's Hospital and British Columbia's Children's Hospital in Vancouver. Parents were asked to respond to a series of questionnaires every 3 months over a 12‐month period. Perceived adherence was evaluated on a 100‐mm visual analog scale (VAS) in the Parent Adherence Report Questionnaire (PARQ). Parental coping, distress, child function, disease severity and duration, perceived helpfulness of treatment, problems encountered, and sociodemographic data were also assessed.

Results

The mean age of our sample of 175 children was 10.2 years; mean age at diagnosis was 6.1 years and mean disease duration was 4.1 years. Perceived adherence to medications was consistently high, with average adherence at baseline, 3, 6, 9, and 12 months being 86.1, 91.7, 90.4, 92.0, and 88.8, respectively, on the PARQ VAS. Perceived adherence to exercise was lower but remained steady, with corresponding means of 54.5, 64.1, 61.2, 63.0, and 54.3, respectively. Using generalized estimating equation analysis, factors associated with higher perceived adherence to medications included perceived helpfulness of medications and lower disease severity; those associated with higher perceived adherence to exercise were younger age of the child, child involvement in responsibility for treatment, and higher perceived helpfulness of the treatment.

Conclusion

Belief in helpfulness of treatment is associated with higher parental perceived adherence to treatment.  相似文献   
16.
The protein kinase C (PKC) family of genes encode serine/threonine kinases that regulate proliferation, apoptosis, cell survival and migration. Multiple isoforms of PKC have been described, one of which is PKCδ. Currently, it is unclear whether PKCδ is involved in promoting or inhibiting cancer formation/progression. The aim of this study was therefore to investigate the expression of PKCδ in human breast cancer and relate its levels to multiple parameters of tumour progression. Protein kinase Cδ expression at the mRNA level was measured using real-time PCR (n=208) and at protein level by both immunoblotting (n=94) and ELISA (n=98). Following immunoblotting, two proteins were identified, migrating with molecular masses of 78 and 160 kDa. The 78 kDa protein is likely to be the mature form of PKCδ but the identity of the 160 kDa form is unknown. Levels of both these proteins correlated weakly but significantly with PKCδ concentrations determined by ELISA (for the 78 kDa form, r=0.444, P<0.005, n=91 and for the 160 kDa form, r=0.237, P=0.023, n=91) and with PKCδ mRNA levels (for the 78 kDa form, r=0.351, P=0.001, n=94 and for the 160 kDa form, r=0.216, P=0.037, n=94). Protein kinase Cδ mRNA expression was significantly higher in oestrogen receptor (ER)-positive compared with ER-negative tumours (P=0.007, Mann–Whitney U-test). Increasing concentrations of PKCδ mRNA were associated with reduced overall patient survival (P=0.004). Our results are consistent with a role for PKCδ in breast cancer progression.  相似文献   
17.
A survey of 40 Singapore Chinese households was performed, obtaining information on major perishable foods purchased for home consumption in the previous week, extent of home consumption (eating in), household dietary habits and housing type, the last as a measure of affluence. Eating out was very common: nine (23 per cent) households ate less than 50 per cent of meals at home. Excluding these nine households, consumption and habits were compared between more affluent and less affluent households. The more affluent households purchased more red meat/offal (P = 0.001), poultry (P = 0.002), vegetables other than green leafy (P = 0.04), fruit (P = 0.007) and eggs (P = 0.04); they also differed significantly in various dietary habits. Significant differences were also observed between English-speaking and Chinese-speaking households. The results suggest that increasing affluence may have brought about substantial dietary change in Singapore, thus meriting further study of the role of diet in changing disease patterns in Singapore.  相似文献   
18.
OBJECTIVE: A growing body of data suggests that a significantly enhanced salivary cortisol response to waking may indicate an enduring tendency to abnormal cortisol regulation. Our objective was to apply the response test to a population already known to have long-term hypothalamo-pituitary-adrenocortical (HPA) axis dysregulation. We hypothesized that the free cortisol response to waking, believed to be genetically influenced, would be elevated in a significant percentage of cases, regardless of the afternoon Dexamethasone Suppression Test (DST) value. METHOD: Using the free cortisol response to waking and the short daytime profile, we tested 18 clinically stable, lithium-responsive subjects from our long-term naturalistic follow-up of monthly DSTs. These tests include salivary testing every 15 minutes during the first hour of waking, followed by samples taken at 3:00 PM and 8:00 PM. RESULTS: While clinically stable on lithium prophylaxis, patients with bipolar disorder (BD) showed a significantly enhanced salivary cortisol response to waking, compared with control subjects (P < 0.03). Cortisol levels 30 minutes after waking significantly exceeded those in the large normative data provided in the literature (P < 0.001). CONCLUSIONS: Our observations support the hypothesis that the free cortisol response to waking can reflect relatively enduring HPA dysregulation, even when lithium-responsive BD patients are clinically well and their DSTs are normal. Because the test is easy to administer, the free cortisol response to waking may hold promise as a marker in studies of high-risk families predisposed to, or at risk for, mood disorders.  相似文献   
19.
Antibodies to Pfs28 block Plasmodium falciparum transmission and when combined with antibodies to Pfs25 provide synergy in blocking transmission. Pfs28 and Pfs25 are immunogenic, have limited antigenic diversity, and are structurally similar and genetically linked on chromosome 10. Pfs28 may prove a useful addition to Pfs25 in an effective transmission-blocking vaccine.  相似文献   
20.
OBJECTIVES: To determine the accuracy of self-reported comorbidities compared with medical record review and the clinical and sociodemographic characteristics associated with accuracy of self-reported comorbidities. STUDY DESIGN: We conducted a prospective study of 458 newly diagnosed head and neck cancer patients using self-administered questionnaire and medical chart review data. Overall and itemwise consistency between self-report and chart review was evaluated. Social, clinical, and demographic characteristics of consistent versus inconsistent responders were analyzed. RESULTS: Seventy-four percent of patients had at least one comorbidity. There was good overall consistency between self-report and chart review (kappa = 0.50). Compared with consistent responders, inconsistent responders were found to be older (P < 0.05), have lower sleep (P < 0.05) and physical activity scores (P < 0.05), be more depressed (P < 0.05), and have more severe comorbidities (P < 0.05). CONCLUSIONS AND SIGNIFICANCE: Self-report may be considered as an alternative to chart review for comorbidity assessment in head and neck cancer patients. Younger patients, those with good general health, fewer depressive symptoms, and mild comorbidities, are more likely to give responses consistent with chart review.  相似文献   
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