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IntroductionThe vaginal orgasm seems to be evocated by the stimulation of the G-spot: a highly sensitive area on the anterior wall of the human vagina. However, the existence of such a spot is controversial.AimTo evaluate, by the use of three-dimensional (3-D) ultrasonography, the anatomic structures of the urethrovaginal space both in polycystic ovarian syndrome (PCOS) patients and eumenorrheic non-hirsute controls.MethodsTwenty-three (Group I) PCOS patients and 25 eumenorrheic young women (Group II) were submitted to two-dimensional (2-D) and 3-D ultrasonography and color Doppler analysis of the urethrovaginal space and of the clitoris.Main Outcome Measures2-D ultrasonographic evaluation of the ovaries and of the urethrovaginal space; color Doppler evaluation of the ovarian stromal arteries, urethrovaginal main feeding artery, and dorsal clitoral arteries; 3-D volume calculation of the urethrovaginal space, and 3-D power Doppler analysis of the vascularization index; flow index; and vascularization flow index; hormonal evaluation.ResultsThe vaginal orgasm was present in 13/23 (56%) patients in PCOS Group and in 13/25 (52%) in the controls. The 3-D reconstruction of the urethrovaginal space demonstrated a gland-like aspect with small feeding vessels: “female prostate.” The 3-D mean volume of the “female prostate” was significantly higher in Group I (0.48 ± 0.21 mL) than in Group II (0.39 ± 0.19 mL; P = 0.044). The Virtual Organ Computer-aided AnaLys (VOCAL) built mean volume of the “female prostate” was positively correlated with the time since intercourse (r = 0.486; P = 0.032), with the total length of the urethrovaginal space (r = 0.616; P = 0.025) and with the testosterone (r = 0.424; P = 0.048) circulating values.ConclusionsThe presence of the G-spot and its role in vaginal orgasm remains controversial. In Italians, and normal weight PCOS patients the hyperandrogenism seems to result in ovarian stromal and “female prostate” hyperplasia. Battaglia C, Nappi RE, Mancini F, Alvisi S, Del Forno S, Battaglia B, Venturoli S. PCOS and urethrovaginal space: 3-D volumetric and vascular analysis.  相似文献   
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Alzheimer's Disease (AD) is a neurodegenerative disorder that mainly affects grey matter (GM). Nevertheless, a number of investigations have documented white matter (WM) pathology associated with AD. The corpus callosum (CC) is the largest WM fiber bundle in the human brain. It has been shown to be susceptible to atrophy in AD mainly as a correlate of Wallerian degeneration of commissural nerve fibers of the neocortex. The aim of this study was to investigate which callosal regions are affected and whether callosal degeneration is associated with the stage of the disease. For this purpose, we analyzed high-resolution MRI data of patients with amnesic mild cognitive impairment (MCI) (n = 20), mild AD (n = 20), severe AD (n = 10), and of healthy controls (n = 20). Callosal morphology was investigated applying two different structural techniques: mesh-based geometrical modeling methods and whole-brain voxel-based analyses. Our findings indicate significant reductions in severe AD patients compared to healthy controls in anterior (genu and anterior body) and posterior (splenium) sections. In contrast, differences between healthy controls and mild AD patients or amnesic MCI patients were less pronounced and did not survive corrections for multiple comparisons. When correlating anterior and posterior WM density of the CC with GM density of the cortex in the severe AD group, we detected significant positive relationships between posterior sections of the CC and the cortex. We conclude that callosal atrophy is present predominantly in the latest stage of AD, where two mechanisms might contribute to WM alterations in severe AD: the Wallerian degeneration in posterior subregions and the myelin breakdown process in anterior subregions.  相似文献   
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We investigated the possible influence of adenylate kinase genetic variability on the effect of maternal smoking on intrauterine selection and development. Adenylate kinase locus 1 belongs to a family of monophosphate kinases that plays an important role in the synthesis of nucleotides involved in several metabolic functions. Three hundred forty-five newborn consecutive infants from the Caucasian population of Rome and 360 consecutive infants from the Caucasian population of Penne were studied. The proportion of newborns carrying AK1*2 allele was analyzed in relation to smoking and maternal age. The effect of smoking on birth weight was also analyzed in relation to AK1 phenotype and maternal age. Statistical analyses have been performed according to SPSS programs. In offspring of women aged 28 years or less, the proportion of newborns carrying the AK1*2 allele is much higher in smoking than in nonsmoking mothers (13.2% versus 2.6%). Such association is lacking in mothers aged more than 28 years (6.5% versus 9.2%). The negative effects of smoke on birth weight is more marked in AK11 mothers than in AK1*2 carriers. The data suggest that zygotes carrying AK1*2 allele are relatively protected from the damaging effects of smoking, resulting in a relatively higher proportion of newborns carrying this allele among smoking mothers.  相似文献   
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BACKGROUND: In head and neck cancer, the locoregional failure of patients with positive margins, vascular or perineural invasion, and extracapsular spread is high and results in poor survival. OBJECTIVE: To assess the effect of adjuvant chemoradiotherapy in improving treatment outcomes among older patients with head and neck cancer. METHODS: Forty patients undergoing radical surgery (median age, 73.5 years [range, 70-78 years]) were enrolled (35 men and 5 women; Eastern Cooperative Oncology Group performance status, grade 0-2). Disease sites included the oral cavity (10 patients), oropharynx (12 patients), hypopharynx (8 patients), and larynx (10 patients); pathological TNM classifications included T1 N2 (8 patients), T2 N1-2 (12 patients), T3 N0-2 (8 patients), and T4 N0-2 (12 patients), with the following poor prognostic factors: positive margins (6 patients), vascular invasion (14 patients), neural invasion (16 patients), and extracapsular spread (26 patients). All patients were treated with carboplatin (30 mg/m2 on days 1-5 of weeks 1, 3, and 5) concomitant with radiotherapy (54.0 Gy to all risk volumes plus 10.0 Gy to high-risk volumes; 5 daily fractions of 1.8 Gy each per week). RESULTS: No grade 4 toxicity was observed. Grade 3 toxicity included mucositis (10 patients), neutropenia (6 patients), dermatitis (2 patients), and thrombocytopenia (1 patient). The radiotherapy dose administered was 52.0 Gy to all risk volumes plus 10.0 Gy to high-risk volumes. Thirty-two patients (80%) received 3 cycles, 6 (15%) received 2 cycles, and 2 (5%) received 1 cycle. Three-year survival was as follows: disease-free survival, 58%; overall survival, 64%; and local control, 79%. CONCLUSIONS: Adjuvant chemoradiotherapy may be successful in fit older patients. The results of adjuvant chemoradiotherapy were better than those observed in a comparable group treated with radiotherapy alone and were similar to those observed in a younger group with the same poor prognostic factors treated with adjuvant carboplatin plus radiotherapy.  相似文献   
88.
The specificities of anti-nuclear antibodies (ANA) reacting with multiple nuclear dots (MND-ANA) present in about 15% primary biliary cirrhosis sera were studied by Western blot analysis with nuclear fractions from a human cell line. Reactivity with two broad bands of 78-92 kD and 96-100 kD of the insoluble fraction was present exclusively in MND-ANA-positive sera. Antibodies eluted from these proteins specifically retained the immunofluorescence reactivity of MND-ANA. Immunomorphological analysis by a pre-embedding technique revealed that the antibody specifically binds to nuclear regions resembling in size and number nuclear bodies. Since these structures are absent in immature rate endometrial cell and can be induced by diethylstilbestrol, we tested MND-ANA by immunofluorescence on cryostat sections of uteri from hormone-treated and untreated immature rats. A strong reaction of nuclear dots was observed predominantly in endometrial cells of hormone treated rats. We thus conclude that MND-ANA present in primary biliary cirrhosis sera are directed against 78-92-kD and 96-100-kD nuclear proteins located in nuclear bodies.  相似文献   
89.
We describe a case of adult-onset biphasic Rasmussen's encephalitis who presented seizures and left dyskinesias at the onset and, after 1 year, language disorder. Serial MRI and [(18)F] FDG-PET scans were performed showing involvement of the right cerebral hemisphere in the first phase and of the contralateral one in the second.  相似文献   
90.
OBJECTIVE: Poor executive functioning is a core deficit in schizophrenia and has been linked to frontal lobe alterations. We aimed to identify (1) prefrontal cerebral areas in which decreased volume is linked to executive dysfunction in schizophrenia; and (2) areas throughout the brain that are volumetrically related to the prefrontal area identified in the first analysis, thus detecting more extended volumetric networks associated with executive functioning. METHOD: Fifty-three outpatients with schizophrenia and 62 healthy controls, matched for age, gender and handedness, were recruited. High-resolution images were acquired on a 1.5 tesla scanner and regional gray and white matter volumes were analyzed by voxel-based morphometry within SPM5 (statistical parametric mapping, University College London, UK). Executive functioning was assessed using the Wisconsin Card Sorting Test (WCST). RESULTS: Twenty-one patients with poor executive functioning showed reduced dorsolateral prefrontal and anterior cingulate gray matter volume as compared to 30 patients with high WCST performance, with a maximum effect in the left dorsolateral prefrontal cortex. Left dorsolateral prefrontal gray matter volume predicted WCST performance after controlling for possible confounding effects of global cognitive functioning, verbal attention span, negative symptoms, illness duration and education. In this area, both patient groups had less gray matter than healthy controls. Left dorsolateral prefrontal gray matter volume was positively related to dorsal prefrontal, anterior cingulate and parietal gray matter volume; and negatively related to thalamic, cerebellar, pontine and right parahippocampal gray matter volume. CONCLUSIONS: Volumetric alterations in prefrontal-thalamic-cerebellar gray matter networks may lead to executive dysfunction in schizophrenia.  相似文献   
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