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21.
22.
Fuster D Navasa M Pons F Vidal-Sicart S Mateos JJ Lomeña F Rodes J Herranz R 《Clinical nuclear medicine》1999,24(12):955-958
Major neuroendocrine tumors contain many somatostatin receptors. This feature allows for the localization of primary tumors and tumor metastases by scintigraphy with the radiolabeled somatostatin analog octreotide. We describe a patient with nonspecific clinical data and ultrasonography and CT that showed an isolated focal lesion in the liver. In-111 octreotide scintigraphy was essential in establishing the diagnosis of liver metastasis from a neuroendocrine tumor confirmed by pathologic findings. Because clinical symptoms recurred, ultrasonography and CT were performed a few months after surgery. Both were negative. However, In-111 octreotide scintigraphy suggested multiple bone metastases and established the diagnosis of bone metastases from a neuroendocrine tumor, which was confirmed by Tc-99m MDP bone scans and MRI. 相似文献
23.
Pons JM Borras JM Espinas JA Moreno V Cardona M Granados A 《The Annals of thoracic surgery》1999,67(3):635-640
BACKGROUND: The aim of this study was to compare the predictive accuracy for open heart surgical mortality between a statistical model based on collection of clinical data and surgeons' subjective risk assessment. METHODS: Predictive discrimination of both risk assessments (surgeons' and model) was compared through the area under the receiver operating characteristic curve. Logistic regression analysis was used to assess the relation between surgeons' and model predictions to actual outcomes. Calibration of the subjective estimates was evaluated with a chi2 test. RESULTS: Overall, the area under the receiver operating characteristic curve was 0.76 for the statistical model and 0.70 for the subjective assessment. Logistic regression analysis showed that the statistical model remained significant after accounting for the subjective assessment. Calibration of subjective mortality predictions was poor. CONCLUSIONS: Surgeons' risk assessment tends to cluster in the middle ranges of risk. Subjective assessment seems accurate in identifying the two extremes of risk but is inaccurate for intermediate risk levels. A multivariate statistical model improves the accuracy of subjective predictions. 相似文献
24.
25.
L. Bertin E. Rey G. Pons J. L. Mathiot M. O. Richard P. Chrétien C. Saint-Maurice C. Moran D. Ginisty G. Olive 《European journal of clinical pharmacology》1991,41(3):251-253
Summary. Twelve healthy children in three age groups anaesthetized for minor surgery were given a single oral dose of tiaprofenic acid (3 mg · kg–1) (TA). Seven blood samples and zero to 8 and 8 to 24 h urines were collected. TA concentrations in plasma and urine were measured by HPLC.No significant difference was found between the age groups in the kinetic parameters of TA and no correlation was found between these parameters and age; tmax=2.12h, Cmax=8.78mg · l–1, AUC(08 h) 33.9mg · h · l–1, AUC=39.3 mg · h · l–1, t1/2=2.35 h, Vz=0.319 l · kg–1, CL=0.094 l · h–1 · kg–1. Renal clearance was 14 ml · h–1. kg–1. 33% of the TA dose was recovered in the 24 h urine, 48% of which was conjugated, whereas in adults, TA is only found in urine as conjugates.The apparent plasma clearance was significantly higher (56%) than in 12 healthy adults given 1.5 mg · kg–1 TA. Volume of distribution and t1/2 did not significantly differ between children and adults. Since no relationship has been established between plasma TA and either efficacy or toxicity, a different dose regimen cannot be recommended in 3–11 year-old children from that in adults. 相似文献
26.
P. Cortina Greus J. L. Alfonso Sanchez I. Frasquet Pons C. Saiz Sanchez C. Cortes Vizcaino J. I. Gonzalez Arraez A. Sabater Pons S. Ruiz 《European journal of epidemiology》1992,8(6):770-775
After describing the evolution of mortality from ischaemic cardiopathy (IC) in Spain from 1951 to 1986, which is tending to stabilize in some age groups, and from cerebrovascular accidents (CVA), which is clearly declining, an attempt is made to relate these developments to the prevalence of the main risk factors (hypertension, cholesterol, tobacco) associated with IC and CVA. Certain advances, though of a limited number, have been made in recent years in the control of arterial hypertension in Spain, although campaigns on a national scale as in other countries have not been carried out. Regarding alimentary factors, there is an obvious increase in the consumption of food rich in proteins and animal fats, abandoning to a great extent the traditional Mediterranean diet, with health care action being limited to the improvement of nutrition education of the public. Furthermore, the consumption of tobacco has been increasing in Spain during the study period in spite of health legislation in force in recent years.It is therefore deduced that there is no obvious relationship between mortality due to IC and CVA and the prevalence of the main risk factors associated with these diseases, especially when taking into account that preventive actions on a public health level have been very limited.Corresponding author. 相似文献
27.
Survival of Purkinje Cells in Cerebellar Cultures is Increased by Insulin-like Growth Factor I 总被引:4,自引:0,他引:4
Insulin-like growth factor I (IGF-I) is a trophic factor for both neurons and glia. Its presence in the developing and adult cerebellum suggests a role for this growth factor in this area of the brain. Recently, we have described the existence of an IGF-I-containing pathway in afferents of Purkinje neurons arising from the inferior olive. In addition, IGF-I receptors are present in the molecular layer of the cerebellar cortex. These observations prompted us to investigate whether the Purkinje cell is a target for IGF-I. Addition of IGF-I to rat cerebellar cultures produced a 7-fold increase in the number of Purkinje cells (calbindin-positive) together with an increase in the calbindin content of the cultures. IGF-I also doubled the number of surviving neurons and produced a moderate, non-significant increase in [3 H]thymidine incorporation by the cultures. On the other hand, basic fibroblast growth factor (bFGF), which is also present in the cerebellum, produced a dramatic increase in both the proportion of astrocytes and in the mitotic activity of the cultures, without affecting neuron survival. We conclude that IGF-I is a specific promoter of Purkinje cell survival and that its effects differ from those produced by bFGF in fetal cerebellar cultures. These findings reinforce our hypothesis that the Purkinje cell is a target neuron for IGF-I action in the developing cerebellum. 相似文献
28.
Dibenzo[a,l]pyrene-induced DNA adduction, tumorigenicity, and Ki-ras oncogene mutations in strain A/J mouse lung 总被引:1,自引:0,他引:1
Prahalad AK; Ross JA; Nelson GB; Roop BC; King LC; Nesnow S; Mass MJ 《Carcinogenesis》1997,18(10):1955-1963
Dibenzo[a,l]pyrene (DB[a,l]P), an environmental polycyclic aromatic
hydrocarbon, is the most potent carcinogen ever tested in mouse skin and
rat mammary gland. In this study, DB[a,l]P was examined for DNA adduction,
tumorigenicity, and induction of Ki-ras oncogene mutations in tumor DNA in
strain A/J mouse lung. Groups of mice received a single i.p. injection of
0.3, 1.5, 3.0, or 6.0 mg/kg DB[a,l]P in tricaprylin. Following treatment,
DNA adducts were measured at times between 1 and 28 days, while tumors were
counted at 250 days and analyzed for the occurrence of point mutations in
codons 12 and 61 of the Ki-ras oncogene. DB[a,l]P in strain A/J mouse lung
induced six major and four minor DNA adducts. Maximal levels of adduction
occurred between 5 and 10 days after injection followed by a gradual
decrease. DB[a,l]P-DNA adducts in lung tissue were derived from both anti-
and syn-11,12- dihydroxy-13,14-epoxy-
11,12,13,14-tetrahydrodibenzo[a,l]pyrene (DB[a,l]PDE) and both
deoxyadenosine (dAdo) and deoxyguanosine (dGuo) residues in DNA as revealed
by cochromatography. The major adduct was identified as a product of the
reaction of an anti-DB[a,l]PDE with dAdo in DNA. DB[a,l]P induced
significant numbers of lung adenomas in a dose- dependent manner, with the
highest dose (6.0 mg/kg) yielding 16.1 adenomas/mouse. In
tricaprylin-treated control animals, there were 0.67 adenomas/mouse. Based
on the administered dose, DB[a,l]P was more active than other environmental
carcinogens including benzo[a]pyrene. As a function of time-integrated DNA
adduct levels, DB[a,l]P induced lung adenomas with about the same potency
as other PAHs, suggesting that the adducts formed by DB[a,l]P are similar
in carcinogenic potency to other PAHs in the strain A/J mouse lung model.
Analysis of the Ki- ras mutation spectrum in DB[a,l]P-induced lung tumors
revealed the predominant mutations to be G-->T transversions in the
first base of codon 12, A-->G transitions in the second base of codon
12, and A-->T transversions in the second or third base of codon 61,
concordant with the DNA adduct profile.
相似文献
29.
Early stage nasopharyngeal carcinoma: radiotherapy dose and time factors in tumor control 总被引:1,自引:0,他引:1
Chang JT; See LC; Liao CT; Chen LH; Leung WM; Chen SW; Chen WC 《Japanese journal of clinical oncology》1998,28(3):207-213
OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the
control of early stage nasopharyngeal carcinoma (NPC) treated with a
combination of external radiotherapy and brachytherapy, MATERIALS &
METHODS: We reviewed the records of 133 patients with early stage
nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who
received definitive radiotherapy in Chang Gung Memorial Hospital from 1979
to 1991. The median follow-up time was 7.1 years with a minimum of 2 years.
All patients were treated with megavoltage external radiotherapy to the
nasopharynx area (63-72 Gy) followed by high dose rate intracavitary
brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks
apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4
Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used
to examine the effect of several variables on prognosis. RESULTS: The
5-year rates were 86.4% for local control, 84.7% for disease free survival,
88.5% for actuarial survival and 84.2% for overall survival. The treatment
group (combination of time and dose of irradiation) was the most important
prognostic factor according to Cox's proportional hazard model. Patients
receiving radiation at a total dose of < or = 75 Gy completed in < 12
weeks showed the best prognosis. CONCLUSION: Treatment time and total
treatment dose are both important factors in treating early stage NPC.
Decreasing the total radiation time to < 12 weeks and not exceeding a
radiation dose of 75 Gy gave the best results.
相似文献
30.