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排序方式: 共有1346条查询结果,搜索用时 15 毫秒
141.
McLoughlin JM Melis M Siegel EM Dean EM Weber JM Chern J Elliott M Kelley ST Karl RC 《Journal of the American College of Surgeons》2008,206(5):879-886
BACKGROUND: Esophageal cancer continues to increase in incidence. Many patients are presenting with stage II or greater disease and proceeding to neoadjuvant chemoradiation therapy before resection. Approximately 30% of patients will achieve a complete response and might not benefit from proceeding to resection. This study will examine the ability of PET to predict patients with a complete pathologic response. STUDY DESIGN: A query of our IRB-approved esophageal database revealed 81 patients who underwent a pre- and postchemoradiation PET scan and then proceeded to esophageal resection. Statistical analysis was performed to determine the ability of PET to predict a complete pathologic response. RESULTS: When comparing posttherapy PET with final pathology, it was determined that PET could not consistently differentiate a complete pathologic response from patients who still had persistent disease. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 61.8%, 43.8%, 70%, 35%, and 56%, respectively, for patients with a complete PET response after neoadjuvant therapy. CONCLUSIONS: A complete PET response after neoadjuvant chemoradiation is not substantially predictive of a complete pathologic response. Patients should still be referred for resection unless distant metastases are identified. 相似文献
142.
Succu S Sanna F Cocco C Melis T Boi A Ferri GL Argiolas A Melis MR 《The European journal of neuroscience》2008,28(4):813-821
Oxytocin (80 ng) injected into the caudal mesencephalic ventral tegmental area (VTA) of male rats induces penile erection. Such an effect occurs together with an increase in nitric oxide (NO) production, as measured by the augmented concentration of NO(2)(-) and NO(3)(-) found in the dialysate obtained from this brain area by means of intracerebral microdialysis. Both effects are abolished by d(CH(2))(5)Tyr(Me)(2)-Orn(8)-vasotocin (1 microg), an oxytocin receptor antagonist, by S-methyl-l-thiocitrulline acetate (20 microg), a neuronal NO synthase inhibitor, or by omega-conotoxin GVIA (50 ng), a N-type Ca(2+) channel blocker, all injected into the VTA 15 min before oxytocin. In contrast, 1H-[1,2,4]oxadiazole[4,3-a]quinoxalin-1-one (40 microg), a guanylate cyclase inhibitor, given into the VTA 15 min before oxytocin, abolishes penile erection, but not the increase in NO production, while haemoglobin (40 microg), a NO scavenger, injected immediately before oxytocin reduces the increase in NO production, but not penile erection. 8-Bromo-cyclic guanosine monophosphate (0.5-10 microg) microinjected into the VTA induces penile erection with an inverted U-shaped dose-response curve; the maximal effective dose being 3 microg. Immunohistochemistry reveals that in the caudal VTA oxytocin-containing axons/fibres (originating from the paraventricular nucleus of the hypothalamus) contact cell bodies of mesolimbic dopaminergic (tyrosine hydroxylase-positive) neurons containing both NO synthase and guanylate cyclase. These results suggest that oxytocin injected into the VTA induces penile erection by activating NO synthase in the cell bodies of mesolimbic dopaminergic neurons. NO in turn activates guanylate cyclase present in these neurons, thereby increasing cyclic GMP concentration. 相似文献
143.
Müller C Forrer F Bernard BF Melis M Konijnenberg M Krenning EP de Jong M 《Cancer biotherapy & radiopharmaceuticals》2007,22(1):151-159
AIM: The aim of this study was to investigate the influence of a diagnostic versus therapeutic dose of [(177)Lu-DOTA-Tyr(3)]octreotate on the uptake, effects, and dosimetry in somatostatin receptor subtype 2(sst2)-positive tumors and normal organs in a rat tumor model. MATERIALS AND METHODS: Lewis rats bearing rat pancreatic CA20948-tumor grafts were injected intravenously with different amounts of radioactivity and peptide of [(177)Lu-DOTA-Tyr(3)]octreotate: 3 MBq/0.5 microg (group A), 3 MBq/15 microg (group B), 300 MBq/15 microg (group C), and 555 MBq/15 microg (group D). Biodistribution studies were performed at several time points between 3 and 13 days post injection. Ex vivo and in vitro autoradiography was performed with frozen tumor sections. RESULTS: Normal sst2-positive tissues showed a significantly higher uptake of radioactivity [%IA/g] when a low peptide amount was injected. On the other hand, the radioactivity concentration [%IA/g] in sst2-negative tissues and organs (blood, muscles, kidney, and liver) were comparable (groups A and B), independent of the injected peptide amount. Initially, this held true for the tumors as well. Yet, over time, we found a decrease in the radioactivity concentration in the tumors of groups A and B, because of tumor growth. On the other hand, therapeutic amounts of radioactivity (groups C and D) resulted in a significant reduction of tumor size, where radioactivity concentration remained higher than in groups A and B, despite the use of the high peptide amounts. Ex vivo autoradiograms of tumor sections confirmed these results. In vitro autoradiography performed on adjacent tumor sections revealed a reduced density of sst2 in tumors from animals that received a therapeutic radioactivity dose. Ki67-antibody immunohistochemistry showed an absence of proliferating tumor cells after therapy. CONCLUSIONS: The differences in radioactivity retention in tumors after diagnostic or therapeutic doses, depending on a change in tumor kinetics, have to be taken into account when calculating tumor-absorbed radiation doses. 相似文献
144.
Melis GB Orrù M Uras R Etzi R Marotto MF Zedda P Angioni S Paoletti AM 《Journal of chemotherapy (Florence, Italy)》2007,19(Z2):17-19
Chorioamnionitis is an inflammation of the placental membranes induced by microorganisms which reach the endometrial cavity from the vagina and uterine cervix. Premature labor frequently depends on infections. In patients with premature rupture of membranes (PROM) antibiotic treatment can prevent intra-amniotic inflammation if it is absent at admission. In spite of antibiotic treatment started immediately after the PROM in 218 patients, the chorioamnionitis did not prevent delivery in 41 patients within 48 hours of PROM. In the presence of a previous chorioamnionitis, antibiotic treatment cannot prevent premature labor, whereas it can prevent infection and lead to a longer duration of pregnancy if PROM does not depend on previous infection. 相似文献
145.
The effect of a pro-erectile dose of apomorphine, a mixed dopamine receptor agonist, and of PD-168077 (N-[4-(2-cyanophenyl)piperazin-1-ylmethyl]-3-methylbenzamide maleate), a selective dopamine D4 receptor agonist, injected into the paraventricular nucleus of the hypothalamus on the concentration of extra-cellular dopamine and its main metabolite 3,4-dihydroxyphenylacetic acid (DOPAC) in the dialysate from the nucleus accumbens was studied in male rats. As expected, apomorphine (0.1microg) and PD-168077 (0.1microg) induced penile erection episodes, which occurred concomitantly to an increase in extra-cellular dopamine and DOPAC concentration in the dialysate from the shell of the nucleus accumbens, as measured by intracerebral microdialysis. When induced by apomorphine, these effects were reduced by 80% by raclopride, a selective D2/D3 receptor antagonist (1microg) and only by 40-45% by L-745,870 (1microg), a selective dopamine D4 receptor antagonist. When induced by PD-168077, these effects were reduced by more than 80% by L-745,870 (1microg), but only by 35-40% by raclopride. Irrespective of the dopamine agonist used to induce penile erection, the pro-erectile effect and the concomitant increase in dopamine and DOPAC concentration in the nucleus accumbens dialysate were almost completely abolished by d(CH(2))(5)Tyr(Me)(2)-Orn(8)-vasotocin(1microg), a potent oxytocin receptor antagonist, given into the lateral ventricles. The present results suggest that stimulation of dopamine receptors (mainly of the D2 to D4 subtype) in the paraventricular nucleus induces the release of oxytocin in brain areas that influence the activity of mesolimbic dopaminergic neurons mediating the appetitive and reinforcing effects of sexual activity. This provides evidence for a role of oxytocin in neural circuits that integrate the activity of neural pathways controlling the consummatory aspects of sexual behaviour (e.g., penile erection) with those controlling sexual motivation and sexual arousal. 相似文献
146.
147.
Part time female sex workers in a suburban community in Kenya: a vulnerable hidden population 下载免费PDF全文
Hawken MP Melis RD Ngombo DT Mandaliya K Ng'ang'a LW Price J Dallabetta G Temmerman M 《Sexually transmitted infections》2002,78(4):271-273
BACKGROUND: In sub-Saharan Africa, female sex workers (FSWs) are a vulnerable high risk group for the acquisition and transmission of sexually transmitted infections (STI) and HIV. OBJECTIVES: To study parameters of sexual behaviour and knowledge of STI and HIV, to describe health seeking behaviour related to STI, and to measure the prevalence of gonorrhoea, chlamydia, syphilis, and HIV-1, to provide baseline data for targeted STI and HIV prevention interventions. METHODS: In a cross sectional survey with snowballing recruitment, between February and March 2000, 503 self identified FSWs in a suburb in Mombasa, Kenya, were interviewed with a structured questionnaire and screened for gonorrhoea, chlamydia, syphilis, and HIV-1. RESULTS: The mean number of sexual partners in the previous week was 2.8 (SD 1.6). The mean number of non-regular clients and regular clients in the previous week was 1.5 (1.0) and 1.0 (0.9) respectively. The median weekly income from sex work was $US15. A total of 337 (67%) women had an alternative income in the informal sector. 146 (29%) and 145 (45%) never used a condom with a client and non-paying partner respectively. The prevalence of gonorrhoea, chlamydia, and syphilis was 1.8%, 4.2%, and 2.0% respectively. The overall HIV-1 seroprevalence was 30.6%. CONCLUSIONS: There is a large need for intensive STI and HIV prevention interventions in part time FSW. 相似文献
148.
van Eijken M Melis R Wensing M Rikkert MO van Achterberg T 《Disability and rehabilitation》2008,30(9):696-708
Purpose. To determine the feasibility of the Dutch Geriatric Intervention Programme (DGIP) in primary care. Within the DGIP, a nurse cooperates with a General Practitioner (GP) and a clinical geriatrician to assess and manage care for community-living older patients. The aim of this study was to describe both views of care receivers and those of professionals in order to identify facilitating factors and barriers for implementation of the DGIP.
Method. Combined quantitative and qualitative data collection methods were used. Pre- and post-questionnaires were taken from GPs (n = 15), nurses (n = 6) and geriatricians (n = 2). These professionals were also interviewed. In addition patients (n = 11 out of total n = 54) and their carers (n = 37) were interviewed.
Results. GPs appreciated the support by the DGIP for problems in cognition, mood and mobility. Lack of knowledge and time restriction was the cause of their incapability at that point. In the cooperation between professionals, nurses felt that they had to initiate the contact. Personal contact helped the mutual communication. Involving the carer of the patient proved very important. All disciplines found this of crucial importance in order to deliver a tailored intervention and create conditions for optimal care. Barriers, for which the programme was tailored during the implementation, were: resistance in referrals of patients to the programme, nurses' and GPs' knowledge of diagnostic tests, communication problems and insufficient involvement of caregivers.
Conclusions. The implementation of the DGIP was feasible, but several barriers need ongoing attention by implementation, like communication between disciplines. 相似文献
Method. Combined quantitative and qualitative data collection methods were used. Pre- and post-questionnaires were taken from GPs (n = 15), nurses (n = 6) and geriatricians (n = 2). These professionals were also interviewed. In addition patients (n = 11 out of total n = 54) and their carers (n = 37) were interviewed.
Results. GPs appreciated the support by the DGIP for problems in cognition, mood and mobility. Lack of knowledge and time restriction was the cause of their incapability at that point. In the cooperation between professionals, nurses felt that they had to initiate the contact. Personal contact helped the mutual communication. Involving the carer of the patient proved very important. All disciplines found this of crucial importance in order to deliver a tailored intervention and create conditions for optimal care. Barriers, for which the programme was tailored during the implementation, were: resistance in referrals of patients to the programme, nurses' and GPs' knowledge of diagnostic tests, communication problems and insufficient involvement of caregivers.
Conclusions. The implementation of the DGIP was feasible, but several barriers need ongoing attention by implementation, like communication between disciplines. 相似文献
149.
Tuveri A Paoletti AM Orrù M Melis GB Marotto MF Zedda P Marrosu F Sogliano C Marra C Biggio G Concas A 《Epilepsia》2008,49(7):1221-1229
Purpose: Seizure exacerbation in catamenial epilepsy (CE) is associated with the decrease in progesterone secretion and increase in estradiol secretion during the premenstrual period. Moreover, experimental evidence suggests that tetrahydrodeoxycorticosterone (THDOC), a positive modulator of the type A receptor for γ-aminobutyric acid (GABA), and dehydroepiandrosterone sulfate (DHEAS), a negative modulator of this receptor, might play a crucial role in modulating seizure frequency during the menstrual cycle. Following these studies it seems of interest to investigate possible variations, among other hormonal parameters, of THDOC and DHEAS in CE patients.
Methods: The serum concentrations of progesterone (P4), pregnenolone, allopregnanolone (AP), THDOC, DHEAS, cortisol, and DHEAS/cortisol ratio were measured throughout the menstrual cycle at the 7th, 11th, 15th, 19th, 23rd, and 27th day from the onset of spontaneous menstrual blood loss in young premenopausal women with CE (n = 17) and age-matched controls (n = 13).
Results: At each time of the study, the serum concentration of THDOC and the DHEAS/cortisol ratio were lower (p < 0.05) in women with CE than in control women. The concentrations of P4, pregnenolone, and AP did not differ between the two groups of subjects.
Conclusions: The reduced serum concentration of THDOC and the reduced DHEAS/cortisol ratio detected throughout the menstrual cycle in women with CE might play a role in CE. Moreover, the peculiar pattern of CE seizure exacerbation might suggest that these neuroendocrine variations are worth investigating in other epileptic syndromes, particularly in those characterized by relevant and uncontrolled variations in seizure frequency. 相似文献
Methods: The serum concentrations of progesterone (P4), pregnenolone, allopregnanolone (AP), THDOC, DHEAS, cortisol, and DHEAS/cortisol ratio were measured throughout the menstrual cycle at the 7th, 11th, 15th, 19th, 23rd, and 27th day from the onset of spontaneous menstrual blood loss in young premenopausal women with CE (n = 17) and age-matched controls (n = 13).
Results: At each time of the study, the serum concentration of THDOC and the DHEAS/cortisol ratio were lower (p < 0.05) in women with CE than in control women. The concentrations of P4, pregnenolone, and AP did not differ between the two groups of subjects.
Conclusions: The reduced serum concentration of THDOC and the reduced DHEAS/cortisol ratio detected throughout the menstrual cycle in women with CE might play a role in CE. Moreover, the peculiar pattern of CE seizure exacerbation might suggest that these neuroendocrine variations are worth investigating in other epileptic syndromes, particularly in those characterized by relevant and uncontrolled variations in seizure frequency. 相似文献
150.