119,338 research outputs found
La evangelización prehispánica y la formación de una identidad criolla en el Perú del siglo XVI
No full textMeccanismi fisiologici del calo dell’ovodeposizione
No full textIl ciclo di ovodeposizione degli ibridi di galline ovaiole e riproduttrici sottoposte ad un regime controllato di allevamento intensivo ha un andamento caratteristico e presenta una fase iniziale crescente, una fase intermedia costante ed una terza fase progressivamente decrescente. Nelle galline ovaiole, il calo di ovodeposizione inizia a 37 settimane di vita e diventa più evidente dopo la 40a settimana. La deposizione dell’uovo si ripete regolarmente per alcuni giorni in un preciso intervallo della giornata che presenta variazioni in funzione della specie considerata. La deposizione di un uovo per più giorni consecutivi è possibile grazie alla presenza di 7-8 grandi follicoli sull’ovario prossimi alla maturazione che formano la cosiddetta scala gerarchica. L’ovodeposizione dipende dalla combinazione di diversi cicli fisiologici che hanno durata diversa: il ciclo di maturazione dei follicoli ovarici, il ciclo di ovulazione, il ciclo di sintesi dell’uovo in ovidutto. L’attività riproduttiva a livello della gonade femminile è controllata dal sistema endocrino ipotalamo-ipofisi-ovario. In particolare, l’ovulazione è sempre preceduta da due picchi ematici di ormone luteinizzante (LH), secreto dall’ipofisi anteriore, e di progesterone, secreto dall’ovario. I picchi preovulatori sono la conseguenza di un picco ematico di induzione di LH che è dipendente dal fotoperiodo somministrato con variazioni specie-specifiche. Il calo di ovodeposizione durante l’invecchiamento della gallina è causato inizialmente dall’aumento dei giorni di pausa a cui successivamente si aggiungono lunghi periodi di alcune settimane di completa assenza dell’ovodeposizione. Il calo dell’attività riproduttiva è associato a diverse manifestazioni: aumento del peso corporeo, diminuzione del numero di grandi follicoli sull’ovario, diminuzione di LH ipofisario ed ematico. Inoltre, anche la risposta ipofisaria all’azione all’azione stimolatrice dei realising-factors ipotalamici, LH-RH I e LH-RH II, diminuisce durante l’invecchiamento. Nella gallina, si ritiene che solo l’LH-RH I svolga una azione stimolatrice sulla sintesi ipofisaria di LH che risulta inferiore in galline di 105 settimane di vita in confronto a galline di 28 settimane.
Il calo riproduttivo nella gallina non sembra dipendere da una ridotta disponibilità di ovociti, situazione invece che si verifica nei primati, poiché il numero di ovociti ancora presenti in ovario è elevato anche in individui di 1 o 2 anni di età La causa principale si ritiene che sia rappresentata da una minore attività del sistema neuroendocrino e quindi minore disponibilità degli ormoni responsabili dell’ovulazione
The uraemic hypertensive patient. a therapeutic challenge-right you are (if you think so)
No full textHigh blood pressure (BP) is a leading cause of chronic kidney disease (CKD) and at the same time represents its most frequent complication. High BP is an independent risk factor for advanced CKD; on the other hand, at least 40% of patients with normal glomerular filtration rate (GFR) and virtually all patients with GFR <30 mL/min are hypertensive. CKD and microalbuminuria are powerful risk factors for cardiovascular morbidity and mortality. Consequently, in uraemic hypertension, it is of utmost importance to carefully manage both high BP and microalbuminuria, in order to slow down the progression of kidney damage and to reduce the incidence of cardiovascular events. The first purpose of the medical treatment in hypertensive patients is to normalize BP, regardless of the drug used. Nevertheless, some drugs have an 'additional' nephroprotective effect at the same BP target achieved. In this regard, first-line drugs are definitely renin-angiotensin-aldosterone inhibitors, mainly for their proved efficacy in reducing hypertension-related kidney damage and proteinuria. Anyway, a combined approach (two or more drugs) is usually needed to achieve the optimal BP target and reduce the worsening of CKD
EPO and HO-1 in cardiovascular and renal protection: just a common signaling pathway or a mechanistic link?
No full textPrimary membranous nephropathy and its treatment: Past, present and future
No full textPrimary membranous nephropathy (PMN) is the most common cause of primary nephrotic syndrome. In the last few years scientific interest mainly focused on the search for new more effective and safer therapeutic strategies and on the guide to their use based on markers of clinical outcomes and disease activity such as the antibodies to the podocyte-expressed phospholipase A2 receptor (PLA2R). The results of the latest trials with the newest pharmacologic approaches open promising horizons in the treatment of membranous glomerulonephritis. This brief review, following the road paved by the previous treatment options, overviews the new advances in the pharmacologic treatment of MN, which represent the near future of its therapy
The CALO Meeting Assistant System
No full textInternational audienceThe CALO Meeting Assistant (MA) provides for distributed meeting capture, annotation, automatic transcription and semantic analysis of multiparty meetings, and is part of the larger CALO personal assistant system. This paper presents the CALO-MA architecture and its speech recognition and understanding components, which include real-time and offline speech transcription, dialog act segmentation and tagging, topic identification and segmentation, question-answer pair identification, action item recognition, decision extraction, and summarization
Treatment with Vitamin E-coated membrane dialysers and cardiovascular protection in dialysis patients.
No full textWarm hepatic ischemia in pigs: effects of L-arginine and oligotide treatment
No full textReperfusion injury represents a key event leading to graft nonfunction. Maintaining adequate nitric oxide levels and stimulating vasodilator synthesis can probably minimize endothelial damage. The aim of this study was to investigate the effect of L-arginine, a substrate of nitric oxide synthesis, and oligotide, a promoter of prostacyclin synthesis, on liver function and morphology after warm ischemia-reperfusion injury. After constructing a side-to-side portacaval shunt, ischemia was induced by clamping the hepatic hilum for 2 h above the shunt, in 19 female pigs divided into a control group (n = 7), an L-arginine treatment group (n = 6), and an oligotide treatment group (n = 6). Liver function tests and measurements of serum and red blood cell malondialdehyde and plasma nitric oxide levels were performed before reperfusion and at 1, 10, 60, and 120 min after reperfusion. Liver biopsies, taken before reperfusion and at 30 min and 7 days after reperfusion, were analyzed for tissue malondialdehyde, histological-ultrastructural features, and apoptosis evaluation. Thirty minutes after reperfusion, liver malondialdehyde, sinusoidal congestion, necrosis, and apoptosis were significantly lower in the L-arginine group than in the controls (p < .05). On postoperative day 7, tissue malondialdehyde decreased, while plasma nitric oxide and hepatocyte glycogen content were increased in the L-arginine group compared to controls (p < .05). This study demonstrates the protective effect of L-arginine on hepatic lipoperoxidation and liver morphology in a pig model of warm ischemia-reperfusion injury. The increased plasma levels of nitric oxide a week after ischemia-reperfusion injury support the hypothesis that it has a role in preventing liver damage. The same beneficial effect was not confirmed for oligotide
Mephedrone and chemsex: a case report
No full textThe chemsex or slamsex phenomenon has attracted attention worldwide, with concerns also expressed by health professionals for the spread of sexually transmitted diseases. Mephedrone or 4-methylmethcathinone, a substituted cathinone homolog of ephedrine, is one of the most popular substances used as a cheaper alternative to other traditional drugs. Fatal cases of chemsex are still rare. We present here the first case-report to the best of our knowledge of a mephedrone-related acute toxicity case in Parma (Italy) detected and quantitated in biological specimens (2.0 mg/L in urine sample, 1.1 mg/L in bile and 1.0 mg/L in central blood while 0.8 mg/L in peripheral blood). None of the other most common drugs of abuse could be detected. Autopsy findings such as facies edematosa, oedema and polyvisceral congestion, interstitial petechiae are compatible elements with a death from acute cardio-respiratory failure, with peri-mortem agony of few minutes in which the cardiac hypertrophy, the moderate aortocoronary sclerosis and mephedrone injection have played a substantial role in the evaluation of the final cause due to an accidental acute intoxication with mephedrone
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