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51.
The frequencies of nine discrete cranial traits are contrasted among 10 skeletal series of central Italy to assess the patterning of biological affinity or divergence. In this study various statistical applications were used: Mean Measure of Divergence (MMD), which was elaborated using the WPGMA cluster analysis, neighbor-joining method and principal coordinate analysis. The results show two main groups divided by the Apennines, which probably were a geographic barrier to biological exchange during the Italian Iron Age. This fact induced endogamous phenomena in the populations on the two sides of Italy (Adriatic and Tyrrenian) and probably increased the familial segregation of traits. The group on the western side has a further division between samples of the central coast and those of the southern coast. The latter samples seem to be more closely connected to Sardinian peoples, and this indicates gene flow and cultural contacts, which were not hindered by the sea. This segregation appears to have receded by Roman times.  相似文献   
52.
Amphetamine (AMPH) is an indirect sympathomimetic compound classified as a substrate-type releaser that distinguishes it from other stimulants that act as uptake 1 blockers, such as cocaine (COC). In mammals, AMPH elicits central stimulation, hypermotility, anorexia, analgesia and analeptic activity, mainly through the increase of extracellular brain dopamine (DA). The inversion of vesicular transporters and/or intravesicular alkalinization is assumed to have a role in AMPH-induced exocytosis. However, the action mechanism of this compound has not yet been completely clarified. Recent evidence on the action of AMPHs indicates potassium channel-blocking properties in peripheral tissues. We investigated the possible involvement of a Shaker-like Kv1.1 channel subtype in the central effects of AMPH, using an antisense oligodeoxyribonucleotide (aODN) that specifically and reversibly inhibits the expression of these channels in the brain. The effect of aODN pretreatments was studied by evaluating the modification of behavioral effects induced in mice through the intracerebroventricular administration of AMPH, COC, or other compounds. The aODN in mice almost completely blocked the stimulatory effects of AMPH and other releasers but was ineffective in reducing the central activity of COC. In aODN-pretreated rats a strong reduction of the AMPH, but not of the COC-stimulated DA efflux from nucleus accumbens was observed. Our results suggest that the stimulant effects of AMPH and chemically related compounds, but not COC, require the presence of functionally active Kv1.1 channels in the brain.  相似文献   
53.
Long-term acetyl-L-carnitine (ALCAR) administration prevents the development of escape deficit produced by acute exposure to unavoidable stress. However, it does not revert the escape deficit sustained by chronic stress exposure. Rats exposed to chronic stress show a low dopamine (DA) output in the nucleus accumbens shell (NAcS) and do not acquire an appetitive behavior sustained by the earning of vanilla sugar (VS) made contingent on the choice of one of the two divergent arms of a Y-maze (VS-sustained appetitive behavior, VAB), while control rats consistently do. The present study shows that ALCAR treatment in rats exposed to a 7-day stress protocol prevented a decrease in DA output in the NAcS and medial prefrontal cortex (mPFC) of rats, and that it strengthened the DA response to VS consummation in the same two areas. Moreover, rats treated with long-term ALCAR or exposed to chronic stress while treated with ALCAR acquired VAB as efficiently as control rats. Moreover, VAB acquisition in stressed rats treated with ALCAR coincided with the reversal of the deficits in escape and in dopaminergic transmission in the NAcS. Thus, repeated ALCAR treatment preserved the DA response to VS in chronically stressed rats and this effect appeared to be predictive of the rat's competence to acquire VAB.  相似文献   
54.
Summary Eight patients, of whom four had acute myeloid leukemia (AML) and four had chronic myeloid leukemia (CML) blast crisis, were treated with a combination of cytosine arabinoside (ARA-C: 1,600 mg/m2 in three patients, 1,200 mg/m2 in five patients), tetrahydrouridine (THU: 2,800 mg/m2 in two patients, 2,646 mg/m2 in one patient, 2,100 mg/m2 in five patients), and carboplatin (900 mg/m2 in four patients, 720 mg/m2 in one patient, 450 mg/m2 in three patients). As a result of this treatment, five of the eight patients became aplastic. Two of the four patients with CML blast crisis reverted to the chronic phase and two of the four patients with acute nonlymphocytic leukemia (ANLL) attained a remission (one partial remission and one complete remission). The major toxicities included myelosuppression, unacceptable hepatotoxicity, and diarrhea. Pharmacokinetics studies revealed that the addition of carboplatin did not significantly change the disposition of ARA-C. ARA-C levels were not significantly changed in comparison with those obtained in a prior study of ARA-C with THU (ARA-C plasma levels at 3 h, 2630±1170 ng/ml).Supported by the Don Monti Memorial Research Foundation  相似文献   
55.
Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne's disease (JD), a chronic gastroenteritis of ruminants and other animals, including primates. Many evidences suggested association of MAP to Crohn's disease, a chronic granulomatous gastrointestinal disease of humans with strong similarities with JD. The present study attempts to evaluate global gene regulation in MAP, which has not been addressed previously, despite the availability of MAP genome sequence. For this purpose, we investigated: (i) the presence of sigma factors and their relationship to sigma factors of other mycobacteria (M. avium subsp.avium, M. tuberculosis, M. bovis, M. leprae and M. smegmatis), and (ii) their expression during different growth conditions and in vitro infection of intestinal epithelial Caco2 cells. MAP genome contains 19 putative sigma factor, but only 12 belong to gene families common to other mycobacteria. Gene expression was evaluated with Real-Time PCR during growth in 7H9 medium and mycobactin J, in 7H9 medium plus mycobactin J and lisozyme, and during infection of Caco2 cells: very different expression patterns were observed and, on the whole, only 7 sigma factors were found to be expressed. sigJ was upregulated during the infection of Caco2 cells. Even if only few sigma factors were expressed in the three conditions tested, the overall high numbers of MAP sigma factors suggests a noteworthy flexibility of this pathogen. Thus, this first report on expression of MAP sigma factors opens the way to an extensive characterization of global gene regulation, as a key to understand strategies of survival and mechanisms of infections used by this organism.  相似文献   
56.
Seventy-four patients with necrotizing pancreatitis were included in a prospective clinical trial of a surgical management protocol comprising necrosectomy and postoperative local lavage of the lesser sac and of the necrosis cavity. Fifty-eight patients showed preoperative organ failures such as pulmonary dysfunctions (57%), renal dysfunctions (37%), shock (12%), and sepsis (26%) in spite of intensive care treatment. The median value of the early prognostic signs was 4.5 points. Intraoperatively, 62% of the patients revealed extensive intrapancreatic parenchymal necrosis, 69% had extrapancreatic necrosis, and 39% showed bacterial contamination of the necrotic material. Following the necrosectomy, postoperative local lavage was performed for an average period of 25 days with 7 liters (median) of lavage fluid per 24 hours. In each of 18 studied patients, a considerable release of immunoreactive trypsin was demonstrated and, in each of 20 studied patients, a high concentration of immunoreactive phospholipase A2 was demonstrated in the lavage fluid up to the 12th/14th postoperative day. The intensive care period averaged 6 1/2 days, the hospital stay averaged 54 days. The hospital mortality rate was 8.1%. It is concluded that restricted necrosectomy and postoperative local lavage treatment correspond in particular to the pathomorphologic conditions and to the local release of biologically active compounds such as bacteria, endotoxin, trypsin, and phospholipase A2 in patients with necrotizing pancreatitis.
Resumen Setenta y cuatro pacientes con pancreatitis necrotizante fueron incluídos en un ensayo clínico prospectivo aplicando un protocolo de manejo quirÚrgico que comprende necrosectomía y lavado peritoneal postoperatorio de la transcavidad de los epiplones y de la cavidad necrótica. Cincuenta y ocho pacientes exhibierion fallas orgánicas postoperatorias tales como disfunción pulmonar (57%), disfunción renal (37%), shock (12%), y sepsis (26%) a pesar de cuidado intensivo. El valor promedio de los signos précoces pronóstico (Ranson), con exclusión de la retención de líquido fue de 4.5 puntos. Los hallazgos intraoperatorios revelaron necrosis pancreática extensa en 62% de los pacientes, necrosis extrapancreática en 69%, y contaminación bacteriana del material necrótico en 39%. Realizada la necrosectomía se instauró lavado peritoneal postoperatorio por un período promedio de 25 días con 7 litros (promedio) de líquido por cada 24 horas. En cada uno de los 18 pacientes estudiados se demostró liberación considerable de tripsina inmunorreactiva, así como una elevada concentración de fosfolipasa A2 inmunorreactiva, en el líquido de lavado hasta el 12/14 días postoperatorios. El período de cuidado intensivo fue de 6 1/2 días, y la hospitalización de 54 días en promedio. La mortalidad hospitalaria fue de 8.1%. En conclusión, se plantea que el tratamiento mediante la necrosectomía restringida y el lavado peritoneal local postoperatorio está indicado en pacientes con las condiciones patomorfológicas de pancreatitis necrotizante que resultan en la liberación local de compuestos biológicamente activos tales como bacterias, endotoxina, tripsina, y fosfolipasa A2. Serán necesarios ulteriores estudios clínicos controlados para confirmar los resultados favorables que hemos obtenido con la necrosectomía y el lavado peritoneal postoperatorio en pacientes con pancreatitis necrotizante y extensa e infectada necrosis pancreática.

Résumé Un essai prospectif d'une méthode de traitement chirurgical consistant en nécrosectomie associée au lavage de l'arrière cavité des épiploons et de la cavité nécrotique a concerné 74 malades présentant une pancréatite nécrotique. Malgrè le traitement intensif 58 d'entre eux ont accusé des complications telles que troubles pulmonaires (57%), rénaux (37%), choc (12%), et infection (26%). La valeur moyenne des signes de pronostic précoce fut de 4.5 points. A l'intervention 62% des opérés présentaient une nécrose pancréatique étendue, 69% des opérés une nécrose extra-pancréatique, 39% une surinfection du tissu pancréatique. Après l'exèrése de la nécrose le lavage fut pratiqué quotidiennement avec en moyenne 7 litres de liquide pendant une période de 25 jours. Chez 18 malades fut constaté une libération importante de trypsine immunoactive et chez 20 malades un taux élevé de phospholipase cA dans le liquide de lavage pendant 12/14 jours après l'intervention. La durée des soins intensifs fut en moyenne de 6.5 jours et celle de l'hospitalisation de 54 jours. Le taux de mortalité opératoire fut de 8.1%. On peut conclure de ces faits que la nécrosectomie limitée, associée au lavage local constitue un traitement adapté aux lésions et à la libération locale d'éléments biologiques pathologiques: bactérie, endotoxine, trypsine, et phospholipase A au cours de la pancréatite nécrotique.
  相似文献   
57.
The technical equipment of today's intensive care unit (ICU) workstation has been characterized by a gradual, incremental accumulation of individual devices, whose presence is dictated by patient needs. These devices usually present differently designed controls, operate under different alarm philosophies, and cannot communicate with each other. By contrast, ICU workstations could be equipped permanently and in a standardized manner with electronically linked modules if the attending physicians could reliably predict, at the time of admission, the patient's equipment needs. Over a period of 3 1/2 months, the doctors working in our 20-bed surgical ICU made 1,000 predictions concerning outcome, equipment need, duration of artificial ventilation, and duration of hospitalization for 300 recently admitted patients. The interviews were made within the first 24 hours after admission. The doctors being interviewed were usually (i.e., in over 90% of cases) unfamiliar with the patient. Information concerning the patient's general state of health, special pre-ICU events, and complications was offered to the interviewed clinician because this information represents standard admission data. It was found that the equipment need (represented by two different setups, high tech and low tech) could be predicted most reliably (96.4% correct predictions) compared with a prediction on outcome of ICU treatment (94.5%), on duration of artificial ventilation (75.4%), and on duration of stay (43.4%). There was no significant (p>0.05) difference in the reliability of predictions between residents and consultants. Factors influencing the postoperative equipment need varied with surgical specialty. The general state of health, as indicated by the ASA classification (p<0.001), and the specific intervention (all multiple-valve replacements needed the high-level equipment standard) appeared to be most important in cardiac surgery, while a state of septicemia was important in general surgery (p<0.001). Our findings suggest that ICU workstations may be standardized into at least two types.  相似文献   
58.
59.
Vitiligo is a skin disorder characterized by depigmented macules secondary to melanocyte loss. An unusual facet is its relation to melanoma: cytotoxic T lymphocytes directed to melanocyte antigens are found in both conditions and imply a breakdown of tolerance, yet the resulting immune reaction is the opposite. The mechanisms at the basis of these opposite effects are not known. Here, we performed a direct comparison of whole melanocyte-specific T cell populations in the two diseases. We demonstrate that neither precursor frequencies of Melan-A/MART-1-specific T lymphocytes nor their status of activation differ significantly. However, by using a tetramer-based T cell receptor down-regulation assay, we documented a higher affinity of vitiligo T cells. We calculated that the peptide concentration required for 50% of maximal receptor down-regulation differed by 6.5-fold between the two diseases. Moreover, only vitiligo T cells were capable of efficient receptor down-regulation and IFN-gamma production in response to HLA-matched melanoma cells, suggesting that this difference in receptor affinity is physiologically relevant. The differences in receptor affinity and tumor reactivity were confirmed by analyzing Melan-A/MART-1-specific clones established from the two diseases. Our results suggest that the quality, and not the quantity, of the melanocyte-specific cytotoxic responses differs between the two pathologies.  相似文献   
60.
Homozygous (Δccr5/Δccr5) and heterozygous (CCR5/Δccr5) deletions in the β-chemokine receptor 5 (CCR5) gene, which encodes for the major co-receptor for macrophage-tropic HIV-1 entry, have been implicated in resistance to HIV infection and in protection against disease progression, respectively. The CCR5/Δccr5 genotype was found more frequently in long-term nonprogressors (LTNP) (31.0%) than in progressors (10.6%, p < 0.0001), in agreement with previous studies. Kaplan-Meier survival analyses showed that a slower progression of disease, i.e. higher proportion of subjects with CD4+ T cell counts >500/μl (p = 0.0006) and a trend toward a slower progression to AIDS (p = 0.077), was associated with the CCR5/Δccr5 genotype. However, when LTNP were analyzed separetely, no significant differences in CD4+ T cell counts (p = 0.12) and viremia levels (p = 0.65) were observed between the wild-type (69 % of LTNP) and the heterozygous (31.0 %) genotypes. Therefore, there are other factors which play a major role in determining the status of nonprogression in the majority of LTNP. Furthermore, there was no evidence that the CCR5/Δccr5 genotype was associated with different rates of disease progression in the group of progressors. Taken together, these results indicate that the CCR5/Δccr5 genotype is neither essential nor sufficient for protection against the progression of HIV disease.  相似文献   
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