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PURPOSE: To examine longitudinal changes in mood and empathy over the course of the internal medicine residency. METHOD: The authors conducted a cohort study of 61 residents who completed the Profile of Mood States (POMS) and the Interpersonal Reactivity Index (IRI) at six time points during their internal medicine residency at a university-based program. (POMS was administered five times, and IRI was administered six times.) The main outcomes measured were trends in mood disturbances and multiple domains of empathy over the three-year residency, and comparisons to norms. RESULTS: Response rates varied from Time 1 to Time 6 (98%, 72%, 79%, 79%, 94%, and 95%, respectively). Interns had better scores on four POMS subscales: Depression-Dejection (p = .0031), Anger-Hostility (p < .0001), Fatigue-Inertia (p < .0001), and Vigor-Activity (p < .0001) compared with later administrations, especially midinternship. By the end of residency all POMS scores were returning towards baseline (effects sizes in the .20 s), but only depression was no longer significantly different. IRI scores showed the decline in Empathic Concern remained over residency whereas Personal Distress peaked midinternship year but approached baseline at the end of residency. Compared with the general population, the graduating residents were less tense, depressed, and confused. Personal Distress was significantly lower than the norm group. CONCLUSIONS: Internal medicine residency presents challenges resulting in common mood disturbances. Although graduating residents appear to be better off than the population norms, some domains of their mood disturbances and empathy never fully recover from their internship year.  相似文献   
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Germ cell tumors of the testes represent a unique paradigm of diseases which can be cured even in extremely advanced phase. Unfortunately, this makes them unique among adult solid tumors. Seminoma and non seminoma are relatively rare with approximatively 25,000 patients in Europe per year, but numbers are increasing world wide. Different strategies are needed depending on stage and prognostic scores. Seminoma is extremely sensitive to radiation therapy and chemotherapy, while all germ cell tumors show a very good response to chemotherapy. Clinical stage I seminoma is currently treated with radiation, single course carboplatin or surveillance policy. Clinical stage I non seminoma can also be approached with different strategies such as retroperitoneal lymph node dissection, observation or one-two courses of standard chemotherapy. Stage II seminoma may be treated with either radiation or chemotherapy, while for all advanced stages chemotherapy is mandatory. Since the mid-eighties PEB (Cisplatin, Etoposide and Bleomycin) is the regimen of choice and no other schedule has proved superior in terms of efficacy. Surgery on the residual disease is crucial to the whole strategy and should be performed or attempted in all cases. Consequently, the correct treatment strategy for these tumors does not depend only on the ability of a single physician, but on a skilled team specialized in this particular tumor. Second line therapies (VeIP, PEI, TIP) can cure 25%–40% of patients, but improved strategies for resistant tumors are desperately needed. High-dose chemotherapy has shown very good results in some studies while being less impressive in others. In any case, it should remain an option for relapsing patients and could be used in some cases of upfront chemotherapy in patients with slow marker decline, but this should only be considered in referring centers.  相似文献   
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Summary The chromophore-modified derivative of doxorubicin, 4-demethyl-6-0-methyl-doxorubicin, has been tested for antitumor activity in a range of experimental murine tumor systems. In contrast to the inactive 6-0-methyl derivative of daunorubicin, 4-demethyl-6-0-methyl-doxorubicin provided antitumor effects comparable to that of the parent compound. In addition, detailed DNA-interaction studies showed that the doxorubicin derivative retains the ability to bind DNA by the intercalation mechanism. However, the binding affinity was appreciably reduced following structural modification in the anthraquinone chromophore. On the basis of the proposed models of intercalation, these results could be rationalized in terms of steric influence of the bulky methoxy group. The results of this study are in agreement with the correlation already observed between DNA binding and relative antitumor activity of anthracyclines.  相似文献   
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New markers have been used to monitor the changes of bone turnover occurring during growth. Data on bone turnover rate during the perinatal period are, however, very scarce. In the present study we evaluated bone turnover rate, assessed by the measurement of urinary N-terminal telopeptide of type I collagen (NTx) concentrations, at different gestational ages, and we documented the trend of bone turnover rate occurring in the first days after birth. Urine samples were obtained from 83 healthy full term newborn infants, 16 preterm, and 17 infants of diabetic mothers (IDMs). The first miction after birth was collected. Urine samples were also collected 24 and 48 h after birth. NTx was measured by an enzyme-linked immunosorbent assay (Osteomark®, Ostex International, Inc. Seattle, WA). The relationship between NTx at birth and all the other variables has been evaluated using multiple regression analysis. The changes of NTx excretion over time and the effect of the groups were studied by multivariate analysis of variance (MANOVA) for repeated measures. We found a remarkable association between gestational age and NTx concentrations at birth (R = 0.56; p < 0.00001). NTx concentrations showed a progressive decrement, reaching a nadir between the 38th and the 42nd week of gestation. The NTx concentrations changed significantly during the first 48 h of life in the three groups. Moreover, preterm infants had NTx excretion values at birth significantly higher than full term infants (p < 0.001), whereas NTx excretion rates of IDMs were not different from those of the other two groups of subjects. In conclusion, gestational age seems to be the major determinant of bone turnover in neonates; NTx excretion rate is higher before term, it slows in proximity of delivery, and it increases significantly during the first 48 h of life. Preterm infants have higher bone turnover rate than full term infants. NTx excretion rate of IDMs was comparable with those of the control subjects.  相似文献   
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The immunosuppressive action of phosphatidylserine has been studied in mitogen-activated human peripheral blood mononuclear cells. The addition of phospholipid (10-60 nmol/10(6) cells) causes a dose-dependent inhibition of DNA synthesis induced by PHA, anti-CD3 mAb, allogeneic lymphocytes and tetradecanoylphorbol acetate plus ionomycin. In contrast, the interleukin-2-dependent DNA synthesis is less affected. Flow cytometric analysis and binding of radioiodinated interleukin-2 show that the phospholipid prevents the expression of interleukin-2 and transferrin receptors. Removal of monocytes by adherence does not change the action of phosphatidylserine. Furthermore, the phospholipid is equally effective in preparations depleted of CD4+ or CD8+ lymphocytes. Phosphatidylinositol partly reproduces the action of phosphatidylserine. Phosphatidic acid, phosphatidylglycerol and phosphatidylcholine are inactive. Also unsaturated phosphatidylserine analogues inhibit DNA synthesis whereas saturated phosphatidylserines do not. The data suggest that phosphatidylserine mainly affect the steps of T cell activation preceding the production of interleukin-2 and the expression of its receptor. The phosphorylserine headgroup and the unsaturated acyl chains contribute to this effect.  相似文献   
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The effects of low frequency-high intensity transcutaneous and intramuscular electrical nerve stimulation (TENS and IENS, respectively) on ipsilateral muscular pain threshold were studied in healthy volunteers. The combined effects of TENS (or IENS) and vibration as well as the effects of TENS applied to contralateral regions were also investigated. Muscular pain threshold was evaluated by the subjects' verbal reports in response to electrical stimulation (wire electrodes) of the vastus medialis muscle and by the appearance of blink response (startle reaction) without habituation. TENS was generally applied to the skin overlying the same muscle, and in some instances to the skin overlying the contralateral vastus medialis or triceps muscle. IENS was performed through the same electrodes used for inducing muscular pain. Vibration was applied to the tendon of ipsilateral quadriceps femoris muscle. TENS consistently induced marked and long-lasting elevations of ipsilateral muscular pain threshold. Comparable results were obtained by IENS. TENS and vibration performed simultaneously induced increases in muscular pain threshold, which were greater than those obtained with each individual conditioning stimulation. TENS proved to be capable of enhancing muscular pain threshold even when applied to contralateral regions; however, these effects were smaller and of shorter duration. The results provide evidence that low frequency-high intensity TENS (or IENS) are effective in raising muscular pain threshold and support the hypothesis that this type of stimulation brings supraspinal control systems into action through the activation of group III afferent fibres.  相似文献   
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