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991.
Francesco La Rosa Anna Maria Petrinelli Liliana Minelli Vito Mastrandrea 《European journal of epidemiology》1997,13(1):9-13
Survival statistics of 4135 incident cases of digestive system cancers in the Umbria region of Italy are reported. The original data are derived from an ad hoc survey carried out in the period 1978--1982. Observed and relative rates at 1, 5 and 10 years are presented separately by sex and age (< 60 and 60 years). In both sexes there are very short survival rates for liver, bile duct and pancreas cancers, whereas about 50% of colon and rectum cancer patients survived at five years. About 20% stomach cancer patients survived at the same time. In males the survival rate for oesophagus cancer is close to 10%. The rates at ten years confirm the trend. Comparisons between sexes show that there is no significant differences in age at first diagnosis. Survival values are higher in females only for rectum cancers. In both sexes, for stomach, colon and rectum sites younger patients had a significantly longer survival than older ones. 相似文献
992.
Carlo Centemeri Chiara Bolego Maria P Abbracchio Flaminio Cattabeni Lina Puglisi Geoffrey Burnstock Simonetta Nicosia 《British journal of pharmacology》1997,121(8):1700-1706
- This study was aimed at characterizing ATP-induced rises in cytosolic free calcium ion, [Ca2+]i, in a population of rat striatal astrocytes loaded with the fluorescent Ca2+ probe Fura2, by means of fluorescence spectrometry.
- ATP triggered a fast and transient elevation of [Ca2+]i in a concentration-dependent manner. The responses of the purine analogues 2-methylthio-ATP (2-meSATP), adenosine-5′-O-(2-thiodiphosphate) (ADPβS), as well as uridine-5′-triphosphate (UTP) resembled that of ATP, while α,β-methylene-ATP (α,β-meATP) and β,γ-methylene-ATP (β,γ-meATP) were totally ineffective.
- Suramin (50 μM) had only a minor effect on the ATP response, whereas pyridoxal phosphate-6-azophenyl-2′,4′-disulphonic acid (PPADS) (5 μM) significantly depressed the maximum response.
- Extracellular Ca2+ did not contribute to the observed [Ca2+]i rise: removing calcium from the extracellular medium (with 1 mM EGTA) or blocking its influx by means of either Ni2+ (1 mM) or Mn2+ (1 mM) did not modify the nucleotide responses.
- Furthermore, after preincubation with 10 μM thapsigargin, the nucleotide-evoked [Ca2+]i increments were completely abolished. In contrast, 10 mM caffeine did not affect the responses, suggesting that thapsigargin-, but not caffeine/ryanodine-sensitive stores are involved.
- Both application of the G-protein blocker guanosine-5′-O-(2-thiodiphosphate) (GDPβS) (1 mM) and preincubation with pertussis toxin (PTx) (350 ng ml−1) partially inhibited the nucleotide-mediated responses. Moreover, the phospholipase C (PLC) inhibitor U-73122, but not its inactive stereoisomer U-73343 (5 μM), significantly reduced the ATP-evoked [Ca2+]i rise.
- In conclusion, our results suggest that, in rat striatal astrocytes, ATP-elicited elevation of [Ca2+]i is due solely to release from intracellular stores and is mediated by a G-protein-linked P2Y receptor, partially sensitive to PTx and coupled to PLC.
993.
Maria Rosaria Melis Salvatora Succu Umberto Iannucci A. Argiolas 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(5):595-600
The possible involvement of nitric oxide in the prevention by morphine of apomorphine- and oxytocin-induced penile erection
and yawning was investigated by measuring the concentration of NO2- and NO3- in the dialysate obtained with a vertical microdialysis probe implanted in the paraventricular nucleus of the hypothalamus
of male rats. Either apomorphine (80 μg/kgs.c.) or oxytocin (30 ng i.c.v.) increased significantly basal NO2- and NO3- concentration in the paraventricular dialysate, penile erection and yawning. Morphine (1, 5 and 10mg/kg i.p.) prevented
dose-dependently either apomorphine or oxytocin responses when given 15min before apomorphine or oxytocin. Prevention by morphine
of apomorphine and oxytocin responses was abolished by naloxone (3mg/kg i.p.) given 15min before morphine. Morphine prevented
apomorphine and oxytocin responses also when given in the lateral ventricles or directly in the paraventricular nucleus. In
contrast, the selective agonist of the kappa opioid receptor subtype U-69,593 was found to be ineffective. The present results
confirm previous findings showing that morphine acts through μ receptors in the paraventricular nucleus to prevent apomorphine
and oxytocin-induced penile erection and yawning and suggest that this morphine effect is mediated by a decreased activity
of nitric oxide in the paraventricular nucleus of the hypothalamus.
Received: 30 September 1996 / Accepted: 24 January 1997 相似文献
994.
Van Leeuwen YD Düsman H Mol SS Pollemans MC Drop MJ Grol RP Van Der Vleuten CP 《Advances in health sciences education : theory and practice》1997,2(1):61-70
Objectives: The relation between the content of postgraduate training for general practice and the outcome in terms of the growth in knowledge of trainees was investigated. The training variables included were: (1) the number of patients seen per day, (2) the trainer, (3) the practice and (4) the theoretical curriculum.Methods: Subjects were 58 trainee-trainer pairs. Growth in knowledge was assessed by two written tests administered with eight months interval. Training variables were evaluated by means of questionnaires and logbook-registration. The correlation was explored between each of the training variables and the knowledge tests scores. To correct for interactional effects, a step-wise multiple regression analysis was performed with the second test as dependent variable and the first test as well as the training variables as independent variables.Results: Significant growth in knowledge was demonstrated. Non of all training variables investigated explained the variance in scores on the second test equally good or better than the scores on the entry test.Conclusions: The impact of the separate training-components on the growth in knowledge, remains unclear. We may speculate, that the sort of knowledge assessed with the written literature based true/false test is different from the sort of knowledge transferred during every day training: evidence based knowledge versus experience based knowledge. Equally valid is the conclusion that these findings fit into the theory that in adult learning the outcome is more learner than teacher dependent.This revised version was published online in September 2005 with corrections to the Cover Date. 相似文献
995.
Battista P Palmirotta R Vitullo P Veri M Colalongo C Rigoli L Fedele F Caruso R Inferrera C Romano F Marianicostantini R Frati L Cama A 《International journal of oncology》1997,10(1):65-70
Microsatellite replication errors (RERs), consisting in random tumour-associated allele contractions or expansions, represent a frequent genetic alteration in gastric cancer and appear to be associated with important clinicopathologic parameters. To verify the role of microsatellite instability in the initial phases of gastric carcinogenesis, we analysed the status of II microsatellites in paired microdissected samples of tumour and unaffected mucosa from 30 cases of early gastric carcinoma. Fifteen tumours (50%) demonstrated RERs: these included 7 cases with RERs at one locus and 8 cases with RERs at 2 or more loci. Cases with 2 or more RERs were more frequent among intramucosal tumours, compared to tumours with submucosal spread (43% vs. 12%) and among tumours staged T1NOMx, compared to tumours staged T1N1Mx (35% vs. 0%). RER-positive microsatellite typings were statistically more frequent among tumours with intramucosal extension, lower stage (T1NOMx) and excavated growth pattern (macroscopic type III), compared to tumours with submucosal extension, higher stage (T1N1Mx) and elevated, flat or depressed growth patterns (macroscopic types IIa-IIb-IIc respectively). The above findings indicate that microsatellite instability occurs early in the progression of sporadic gastric cancer and tends to be associated with good prognostic indicators. 相似文献
996.
Maria A. Ros Domingo Macias John F. Fallon Juan M. Hurle 《Anatomy and embryology》1994,190(4):375-382
By in situ hybridization we studied the expression patterns of Msx and Hoxd genes during the late development of the chick leg autopodium (foot) and compared them to patterns during the experimental development of interdigital extra digits. Extra digits are induced in the third interdigital space after various experimental manipulations, such as transient isolation of the interdigit, or removal of the interdigital marginal ectoderm and mesoderm. Msx1 and Msx2 are normally expressed in the interdigital tissue programmed to die. Our experiment changes the fate of the interdigital tissue from cell death to chondrogenesis and provides a good model for studying Msx involvement in defining areas of programmed cell death. Among the proposed roles for Hoxd genes is their involvement in the specification of digit identity early in development. The induction of extra digits allows us to examine whether this new morphogenetic commitment of the interdigital tissue involves changes in the domains of expression of Hoxd genes. Our results show that extra digits develop without a previous modification of the normal pattern of expression of Msx or Hoxd genes. This observation does not support the correlation between the expression of Msx genes and programmed cell death and suggests a role for these genes in maintaining the interdigital tissue in an undifferentiated state. Our results show that an increased number of digits can be formed without modifications in the pattern of expression of the 5-located Hoxd genes and suggest the existence of latent or residual digit organization mechanisms past the time when digits are normally determined, independent of Hoxd gene expression. 相似文献
997.
Maria Svetlova Ljudmila Solovjeva Grigory Stein Claude Chamberland Baldev Vig Nikolai Tomilin 《Chromosome research》1994,2(1):47-52
Recentin situ hybridization studies suggested that within the range of 0.1–1.0 Mb, human interphase chromosomes follow a random walk model (i.e. they behave as flexible polymers without major constraints). However, chromosome structure may differ in the G1, S, and G2 phases, and phase-specific constraints may be masked if the chromosome analysis does not discriminate between the phases. Therefore, using confocal microscopy, we examined the structure of S-phase chromosomes labelled with 5-iododeoxyuridine after prolonged treatment with 5-fluorodeoxyuridine. In the S-phase, labelled 0.32 µ chromosome fibres mostly appear as semi-circles with an average diameter of 0.83 ±0.03 µ. These semi-circles are joined together to form different 3D structures, and two semicircles frequently adopt s- or-like conformations involving about 2.5 µ of the chromosome contour length (L). Morphometric analysis of the S-phase fibres suggests that our data fit both the random flexible polymer model and also a model in which two constrained semi-circles are attached to each other by a flexible joint, thus eliminating constraints at long distances (L more than 2 µ). 相似文献
998.
Maria G. Cattell 《Journal of cross-cultural gerontology》1994,9(2):157-178
Among Abaluyia of Kenya relative age (seniority) structures relationships hierarchically among co-wives, siblings and females of different generations. Ambiguous equality and affectionate informality in grandmother-granddaughter relationships mute the hierarchical implications of their different age and generation statuses. This facilitates grandmothers' educational roles although, as grandmothers say, Nowadays it isn't easy to advise the young. Increased physical, cognitive and experiential distances between these generations resulted from radical changes in the female lifecourse associated with modernization and delocalization. Nevertheless, reciprocal exchanges continue. Granddaughters are also intermediaries in exchanges between older women and their adult daughters. Some grandmothers are denied the companionship and assistance of granddaughters caught in the middle of mother-in-law/daughter-in-law conflicts. Many grandmothers assume parental responsibilities as they deal with the modern problem of daughters' premarital pregnancies. All in all, these intergenerational relationships reveal both cultural persistence and the effects of social change, and continue to have instrumental and expressive value for both grandmothers and granddaughters. 相似文献
999.
Till now the immunohistochemical studies on the procathepsin D expression in breast cancer have been performed using polyclonal antibodies on paraffin-embedded sections because the monoclonal ones were considered effective only on frozen sections. In this study we compared the MAb M1G8 reactivity, which recognizes the 52 Kd procathepsin D, on a series of frozen and paraffin-embedded sections of the same specimen from 22 breast cancers, using the immunohistochemical method. This methodological choice was due to the necessity to perform further studies with monoclonal antibodies using archival material to clarify the procathepsin D prognostic role. MAb M1G8 was clearly positive with a 100% concordance rate both in frozen and paraffin sections of the same specimen. 相似文献
1000.
Antonio Pezzano Giovanni Call Angela Milazo Rossana Fusco Gabriella de Pieri Francesco Faletra Antonio Pezzano Jr. 《The International Journal of Cardiac Imaging》1995,11(3):177-184
For noninvasive evaluation of anatomy and flow characteristics of internal mammary artery graft (IMA-graft), 2D echo-Color-Doppler (CDE) was performed in 60 patients (54 M, 6 F, mean age 54.1±6.9 y), who underwent coronary angiography 20.1 ±13 months after a coronary artery bypass graft (CABG).CDE was performed, using an echocardiographic unit equipped with a 5 MHz linear transducer.In all patients, measurements of IMA-graft diameter (mm), and peak systolic and diastolic flow velocity (cm/sec) were obtained at baseline and also in 16 patients after dipyridamole infusion (0.54 mg/Kg/min) and in 10 patients after sublingual nitroglycerin (NTG) (0.4 mg). Angiography showed the IMA-graft patency in 58/60 patients (96.8%).A typical biphasic flow was displayed by CDE in 49/58 patients (84.4%) with angiographic patency.Dipyridamole infusion increased both IMA-graft diameter and peak diastolic flow velocity (PDFV) from 2.28 ±0.51mm to 2.9 ±0.42mm and from 19.4 ±6.2 cm/sec to 93.9 ±29 cm/sec, respectively (p<0.0001).No significant modifications of peak systolic flow velocity (PSFV) were observed.NTG increased PDFV from 29.11 ±8 cm/sec to 41.88 ±7.20 cm/sec (p<0.005), while diameter and PSFV showed no statistically significant modifications.CDE is a useful diagnostic tool for noninvasive evaluation of IMA-graft patency both early after surgery and during long-term follow-up. CDE pharmacological stress improves the sensibility of the technique and it can provide indirect information about pathophysiology of recipient coronary vessel. 相似文献