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101.
This study analyzes morphometrically 17 skulls of the Mediterranean monk seal Monachus monachus housed in different Italian Museums and collections. We considered several morphometric variables (31 linear, 1 volumetric and 1 surface area measurements). In addition, we identified, measured and compared two nonmorphometric variables, namely, the bone densities of selected areas obtained using a dual‐energy X‐ray absorptiometry (DXA) device. The high correlation coefficient of all variables indicated continuous growth with the onset of age. The ranking of the hierarchical cluster analysis identified the presence of three main groups containing individuals of similar sizes: lactating pups and yearlings; subadult individuals and adult females; and adult males. Smaller groups were identified within these clusters, and their respective allocations into two subgroups were argued on the basis of skull development and other factors. The discriminant analysis of the three main groups indicated a discriminant diagnostic key, based on condilobasilar length (CBlr‐L); maximum mandibular branch height (MB‐H); and surface area of the bulla tympanica. The proposed diagnostic key is useful to classify monk seal skulls of unidentified age and sex. The data reported here suggest that in this species certain adult skull growth features (enhanced tympanic bullae surface area extension, occipital bone density) are sexually dimorphic and possibly related to specific anatomical functions. These functions may include an enhanced auditory capacity; an increased development of the cranial musculature capable of supporting a large skull and guaranteeing the mandibular strength necessary for mastication; and male to male social interactions. Anat Rec, 292:544–556, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
102.
In addition to its high proportion of oleic acid (which is considered as "neutral" in terms of cardioprotection), extra virgin olive oil is rich in phenolic compounds, which other vegetable oils do not contain. This review critically appraises the current scientific evidence of a healthful role of olive phenols, with particular emphasis on hydroxytyrosol and related molecules.  相似文献   
103.
It is known that melanoma develops as a consequence of multifactorial alterations. To date several studies indicate the effective implication of p16 as a tumor suppressor gene with a major role in either the development or progression of human melanoma. Deregulation of melanoma cell growth has been widely associated with mutations in the p16-cyclin D/cdk4-pRb pathway. Recently anticancer therapies are focused on restoration of p16 CDK inhibitory function and other proteins unregulated in melanoma cell cycle pathway (e.g., c-myc, p27). A combined strategy for restoration of normal homeostasis in the melanoma skin with targeted delivery of apoptosis-inducing agents does not seems to be far obtained. New class of antitumoral agents are emerging: histone deacetylase (HDAC) inhibitors have attracted much interest because of their ability to arrest cell growth, induce cell differentiation, and in some cases, induce apoptosis of cancer cells. Recently, attention has been focused on the ability of HDAC inhibitors to induce perturbation in cell cycle regulatory protein (e.g., p21(CIP1)) and down-regulation of survival signalling pathway. In the present study, we have examined the effect of valproic acid (VPA) on M14 human melanoma cell line. Here we observed that VPA induces cell cycle arrest and apoptosis sensitising melanoma cells to cis-platin and etoposide treatment. IC(50) dose (2.99 mM) of VPA was able to induce G(1) arrest (up to 75%) in association with upregulation of p16, p21 and cyclin-D1 related to Rb ipo-phosphorilation. In addition VPA activated apoptosis (50%) in M14 cells, when given alone or in combination with antitumoral agents. The ability of valproic acid to reestablished the G(1) pathway in melanoma cells suggests a potential application of VPA in melanoma therapeutic protocols.  相似文献   
104.
Hypertrichosis is defined as excessive hair growth anywhere on the body in either males or females. It may be caused by genetic conditions, endocrinological disorders, exposure to specific medications (including phenytoin, minoxidil and diazoxide) and other less frequent causes. We report the case of a 1-year-old boy with a family history of thyroid disease and alopecia areata who presented with generalized hypertrichosis due to secondary exposure to topical minoxidil. We discuss an uncommon cause of hypertrichosis and the importance of considering a wide differential diagnosis.  相似文献   
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Several members of the different glutathione transferase (GST) gene classes are polymorphic. Particular interest has been focused on the GSTP class because this gene class is up-regulated during the early stage of oncogenesis and is significantly overexpressed in many human tumors. It has also been shown that high levels of GSTP1 expression are associated directly with tumor drug resistance and with poor patient survival. Our aim was to understand the possible association between GSTP1 polymorphism and cellular response to chemotherapeutic drugs in neuroblastoma. In fact, several antineoplastic drugs used in the neuroblastoma high-risk chemotherapeutic protocol are potential substrates of GSTP1-1 (etoposide, adriamycin and carboplatin). The GSTP1 genotype homozygote *A/*A was identified in 11 patients independent of their response to the chemotherapeutic treatment. Only four patients had a heterozygote genotype A*/B*. Therefore, based on our preliminary data, we were not able to conclude that GSTP1 polymorphism had an impact on patient response to treatment in neuroblastoma.  相似文献   
109.
OBJECTIVE: To compare body water (V) estimates from the Chertow formula (Vc), which was derived in an end-stage renal disease population, to V estimates from the Watson formulas (Vw) in continuous ambulatory peritoneal dialysis (CAPD) patients. To identify CAPD patients in whom Vc is preferred to Vw for clearance studies. DESIGN: Retrospective analysis of clearance studies. SETTING: Dialysis units of four academic medical centers. PARTICIPANTS: 302 subjects on CAPD. INTERVENTION: 613 clearance studies by standard methods. MAIN OUTCOME MEASURES: Comparisons between Vc and Vw, and between urea clearance normalized by Vc [(KtVc)ur] and Vw [(Kt/Vw)ur]. RESULTS: Vc exceeded Vw by 3.5 +/- 1.6 L (p < 0.001), or 9.6% on average. This degree of overestimation of Vw is in the range of body water estimates found in CAPD subjects with severe volume overload (> 5% of body weight) in previous studies.Total (Kt/Nw)ur exceeded total (Kt/Vc)ur by 8.6%. By linear regression, Vc = -0.589 + (1.112 x Vw), r = 0.983. Vw exceeded Vc in only 12 studies. Young age, short height, low body weight, and low prevalence of diabetes characterized the studies with Vw > Vc. Total (Kt/Vw)ur was adequate (> or = 2.0 weekly) in 276 studies. Among these, 74 studies had inadequate total (Kt/Vc)ur (< 2.0 weekly). By logistic regression, the predictors of inadequate (Kt/Vc)ur, when (Kt/Vw)ur was adequate, included the presence of diabetes, great height, and long duration of CAPD. CONCLUSIONS: Vc provides estimates of body water exceeding those provided by Vw in a great majority of CAPD patients. Consequently, approximately 25% of the clearance studies that are adequate when Vw is used as the normalizing parameter may be inadequate when Vc is used. Vc may provide a more appropriate estimate of body water than Vw in CAPD patients with volume overload.  相似文献   
110.
Several lines of evidence support the presence of DNA damage in somatic cells of Parkinson's disease (PD) patients due to the formation of free radical species. In order to detect spontaneous chromosome and primary or oxidative DNA damage, we performed the human lymphocyte micronucleus assay (HLMDA) and comet assay in 19 PD patients and 16 healthy controls. Compared with controls, PD patients showed a significant increase in: (1) spontaneous micronucleus (MN) frequency (p<0.001); (2) single strand break (SSB) levels (p<0.001); and (3) oxidized purine base levels (p<0.05). The chromosome damage and the increased levels of oxidized purine bases observed in our patients support the hypothesis of oxidative stress as a relevant factor in the pathogenesis of PD.  相似文献   
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