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61.
Background. Prior studies of recall accuracy for screening mammogram behavior have examined relatively homogeneous groups. Data are limited on possible systematic group differences, so we evaluated women's recall accuracy in two separate care systems in one city.Methods. Women 50 to 70 years old with and without screening mammograms 10 to 14 months prior were identified from fiscal, clinic, and radiology records at a military care system (MCS) and a county-funded system (CFS) for indigents. Mammogram status was verified through radiology records. Women were excluded if mammograms were diagnostic, done for other than annual screening, or had abnormal results. Interview ers blinded to mammogram status surveyed randomly selected eligible women.Results. For 62 screened/31 unscreened MCS women and 78 screened/61 unscreened CFS women, specificity was similar, at 65 and 62%, respectively. In contrast, sensitivity varied significantly: 95% versus 79% (P = 0.011). Primary ethonocultural groups were Euro-American (MCS—60%) and Mexican American (CFS—85%). Although not different in specificity of recall (67% versus 61%), these major subgroups significantly differed in sensitivity (97% versus 80%, P = 0.017), proportion of true negatives due to never having a mammogram (35% versus 57%, P = 0.003), and proportion with ≥high school education (78% versus 19%, P < 0.00001).Conclusion. Systematic differences in recall validity may exist and compromise the accuracy of intergroup comparisons.  相似文献   
62.
A 7-month-old infant with typical features of diencephalic syndrome (DES) associated with a hypothalamic mass, most probably a glioma, was treated with chemotherapy. The tumor showed clear shrinkage, but after more than 2 years regrowth was noted. During the treatment period the child regained normal growth and became free of symptoms. As radiation therapy, especially at a young age, has significant adverse effects and a neurosurgical approach to the diencephalic region also has the potential to cause significant sequelae, a chemolherapeulic option, when it exists, is preferred. Thus, in an infant in whom a glioma is suspected to be the cause of the DES, based on the clinical picture and the neuroimaging appearance, chemotherapy should be considered the primary therapeutic modality. Even if its effect is temporary, its use is well justified. The most appropriate treatment protocol still needs to be determined.  相似文献   
63.
At the present time multiple chemical sensitivities (MCS) is generally acknowledged to be a poorly understood clinical syndrome which is exhibited by individuals exposed to low levels of exposure to environmental agents that the general population tolerate quite well. A wide range of individual symptoms (typically multiple and related to neurologic, endocrine/metabolic, and immunological, often occurring simultaneously) are displayed by MCS patients. Questions concerning whether or not MCS is a real clinical condition, a form of psychiatric illness or a combination of both remain to be unambiguously clarified.  相似文献   
64.
Yttrium-90 is used for palliative therapy for the treatment of skeletal metastases, but because it is a pure - emitter, data on the pharmacokinetics and radiation doses to metastases and unaffected organs are lacking. To obtain such data, the present study employed yttrium-86 as a substitute for90Y, with detection by positron emission tomography (PET). The study compared the properties of two different86Y complexes —86y-citrate and86Y -ethylene diamine tetramethylene phosphonate (EDTMP) — in ten patients with prostatic cancer who had developed multiple bone metastases (the ten patients being divided into two groups of five). Early dynamics were measured up to 1 h post injection (p.i.) over the liver region, followed by subsequent whole-body PET scans up to 3 days p.i. Absolute uptake data were determined for normal bone, bone metastases, liver and kidney. Radiation doses were calculated according to the MIRD recommendations. Based on the pharmacokinetic measurements of the distribution of the86Y complexes, it was possible to calculate radiation doses for the bone metastases and the red bone marrow delivered by complexes containing90Y. In 1 cm3 of bone metastasis, doses of 26±11 mGy/MBq and 18±2 mGy/MBq were determined per MBq of injected90Y- citrate and90Y- EDTMP, respectively. The doses to the bone marrow were 2.5±0.4 mGy/MBq for90Y- citrate and 1.8±0.6 mGy/MBq for90Y-EDTMP.86Y and PET provide quantitative information applicable to the clinical use of90Y. This method may also be useful for the design of other90Y radiopharmaceuticals and for planning radiotherapy dosages.  相似文献   
65.
We assessed the records of 101 patients with locally advanced transitional cell carcinoma (TCC) of the renal pelvis and ureter treated with postoperative radiation therapy to determine outcome and patterns of failure. Locally advanced disease (i.e., T3–4N0 or N+ disease) was identified in 65 patients. Postoperative radiation was used to treat 86 patients, with a median dose of 35 Gy in 20 fractions over 4 weeks to the tumor bed and regional lymph nodes. There were 15 patients with no residual disease who were offered no further therapy. No patient received postoperative chemotherapy. Prognostic factors were examined using univariate and multivariate analysis, and the patterns of failure were identified after postoperative irradiation. Median follow-up was 9.3 years, during which 76 deaths occurred. The 5-year overall survival was 43% and 10-year survival was 23%. A multivariate analysis identified T3 category, lymph node involvement, and age at diagnosis as significant prognostic factors for survival. Tumor grade was a significant prognostic factor on univariate analysis but not on multivariate analysis. Failure analysis showed that only 36% of patients with locally advanced disease remained relapse free. For this group of patients, distant metastases developed in 53%, and locoregional failured occurred in 35% despite postoperative irradiation. Locoregional failure occurred in 95% of patients with nodal involvement who received postoperative radiation, and 77% of those developed distant relapse. This leads us to conclude that patients with resected locally advanced (T3, T4N0, N+) TCC of the upper urinary tracts have a high risk of relapse and death from disease despite postoperative radiotherapy. Because the main feature of the disease is early distant failure, post-operative chemotherapy is required to improve the outcome for this group of patients.  相似文献   
66.
A genetic analysis of amphetamine-induced hyperthermia was conducted in inbred mice of the strains Balb/c and C3H and in their F1F2 and backcross generations. The results of biometric analysis indicate that the effect of amphetamine on body temperature is genetically determined. The mode of inheritance characterized by a partial dominance (Balb/C over C3H strain). However, a possible matermal effect of C3H can overcome the dominant effect in male progenies and inhibit amphetamine hyperthermic effect.  相似文献   
67.
Summary In the rat, elevating dopamine content in corpus striatum with electrical stimulation of substantia nigra or direct administration of apomorphine (50–200g) into the lateral cerebral ventricle or apomorphine (2–10g) into the caudate-putamen complex decreased pain sensitivity (as shown by an increase in the latency to hind-paw lick in the hot plate test). Furthermore, the decreased pain sensitivity after the central administration of apomorphine was antagonized by pretreatment with haloperidol (a dopamine antagonist). On the other hand, lowering dopamine content in corpus striatum with electrolytic destruction of substantia nigra and 6-hydroxydopamine lesions to the substantia nigra, as well as direct injection of haloperidol into the lateral cerebral ventricle or caudate-putamen complex increased pain sensitivity. The data indicate that activation of striatal dopamine receptors in rat brain induces pain inhibition.  相似文献   
68.
Summary The sensitivity of peripheral tissues to insulin is of pathophysiological, therapeutic and possibly also of prognostic relevance. Calcium channel blockers are widely used in the treatment of cardiovascular disorders that are commonly associated with decreased insulin sensitivity (SI). To evaluate the effects of calcium channel blokkade on SI, glucose homoeostasis and lipid profiles, studies were made of SI (determined by the Minimal Model Method of Bergman), basal glucose and insulin levels, serum total triglyceride (Tg) and lipoprotein cholesterol (C) fractions and certain other variables in 38 healthy young men (24 y) during placebo and after 3 weeks of calcium channel blockade with amlodipine 5 mg once daily. Measurements were made after 3 days on a standard diet (2200 kcal · day–1, 45% carbohydrates, 40% fat and 15% proteins) and after an overnight fast. Compared to placebo, amlodipine decreased supine systolic blood pressure (P<0.01). Heart rate, body weight and 24 h urinary sodium excretion were unaltered, and so were fasting plasma glucose (placebo vs amlodipine: 4.86 vs 4.83 mmol·1–1, respectively) and insulin levels (7.7 vs 7.9 U·ml–1), SI (10.5 vs 9.6·10–4 × min–1 pro U·ml–1), serum total Tg, C and lipoprotein C fractions.The findings demonstrate unchanged insulin sensitivity and secretion, as well as lipoprotein regulation, during maintenance administration of 5 mg amlodipine daily to healthy young men.This work was supported in part by the Swiss National Science Foundation  相似文献   
69.
70.
药敏纸片的质量控制研究   总被引:1,自引:0,他引:1  
目的:探讨和研究药敏纸片质量控制的方法。方法:以克拉霉素药敏纸片为例,参照美国临床实验室标准化委员会(NCCLS)和联邦法规全书(CFR)的方法,建立一套药敏纸片质量控制的指标,包括鉴别、检查及含量测定。结果:采用专属性较强、灵敏度较高的TLC法进行鉴别,最低检出量为50μg;制订纸片的的直径、重量差异、含量均匀性及干燥失重作为检查项,采用短小芽孢杆菌(Bacillus pumilus)[CMCC(B)63202]作为检定菌,进行含量测定。结论:建立的克拉霉素药敏纸片质量标准能够控制其质量,可作为其他抗生素药敏纸片建立质量标准的参考。  相似文献   
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