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91.
Innovations in design of a dedicated breast scanner resulted in automation of the scanning process, the production of high resolution images of the whole breast and an efficient mode of image review. The results of clinical evaluation of the prototype of this breast scanner investigating normal breasts as well as benign and malignant breast lesions are presented.  相似文献   
92.
Social play behavior is a characteristic, vigorous form of social interaction in young mammals. It is highly rewarding and thought to be of major importance for social and cognitive development. The neural substrates of social play are incompletely understood, but there is evidence to support a role for the prefrontal cortex (PFC) and striatum in this behavior. Using pharmacological inactivation methods, ie, infusions of GABA receptor agonists (baclofen and muscimol; B&M) or the AMPA/kainate receptor antagonist 6,7-dinitroquinoxaline-2,3(1H,4H)-dione (DNQX), we investigated the involvement of several subregions of the medial PFC and striatum in social play. Inactivation of the prelimbic cortex, infralimbic cortex, and medial/ventral orbitofrontal cortex using B&M markedly reduced frequency and duration of social play behavior. Local administration of DNQX into the dorsomedial striatum increased the frequency and duration of social play, whereas infusion of B&M tended to have the same effect. Inactivation of the nucleus accumbens (NAcc) core using B&M increased duration but not frequency of social play, whereas B&M infusion into the NAcc shell did not influence social play behavior. Thus, functional integrity of the medial PFC is important for the expression of social play behavior. Glutamatergic inputs into the dorsomedial striatum exert an inhibitory influence on social play, and functional activity in the NAcc core acts to limit the length of playful interactions. These results highlight the importance of prefrontal and striatal circuits implicated in cognitive control, decision making, behavioral inhibition, and reward-associated processes in social play behavior.  相似文献   
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The classification of Bright''s Disease has claimed much attcntion during the present century. Some clinicians content themselves with the simple division into acute and chronic nephritis. This seems hardly adequate when one considers the varying types of the disease which one encounters.  相似文献   
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NTRODUCTIONNanoparticle(NP)isancoloidaldispersionsystem,withdiametersrangingfrom10nmto1000nm.Theparticlesexistmainlyintheorga...  相似文献   
97.
The therapeutic approach is crucial to prostate cancer prognosis. We describe treatments and outcomes for a Spanish cohort of patients with prostate cancer during the first 12 months after diagnosis and identify the factors that influenced the treatment they received.This multicenter prospective cohort study included patients with prostate cancer followed up for 12 months after diagnosis. Treatment was stratified by factors such as hospital, age group (<70 and ≥70 years), and D’Amico cancer risk classification. The outcomes were Eastern Cooperative Oncology Group (ECOG) performance status, adverse events (AEs), and mortality. The patient characteristics associated with the different treatment modalities were analyzed using multivariate logistic regression.We included 470 men from 7 Spanish tertiary hospitals (mean (standard deviation) age 67.8 (7.6) years), 373 (79.4%) of which received treatment (alone or in combination) as follows: surgery (n = 163; 34.7%); radiotherapy (RT) (n = 149; 31.7%); and hormone therapy (HT) (n = 142; 30.2%). The remaining patients (n = 97) were allocated to no treatment, that is, watchful waiting (14.0%) or active surveillance (5.7%). HT was the most frequently administered treatment during follow-up and RT plus HT was the most common therapeutic combination. Surgery was more frequent in patients aged <70, with lower histologic tumor grades, Gleason scores <7, and lower prostate-specific antigen levels; while RT was more frequent in patients aged ≥70 with histologic tumor grade 4, and higher ECOG scores. HT was more frequent in patients aged ≥70, with histologic tumor grades 3 to 4, Gleason score ≥8, ECOG ≥1, and higher prostate-specific antigen levels. The number of fully active patients (ECOG score 0) decreased significantly during follow-up, from 75.3% at diagnosis to 65.1% at 12 months (P < .001); 230 (48.9%) patients had at least 1 AE, and 12 (2.6%) patients died.Surgery or RT were the main curative options. A fifth of the patients received no treatment. Palliative HT was more frequently administered to older patients with higher tumor grades and higher Gleason scores. Close to half of the patients experienced an AE related to their treatment.  相似文献   
98.
Cystic intracranial lesions: magnetic resonance imaging   总被引:4,自引:0,他引:4  
Thirty-three patients with cystic intracranial lesions were examined with both magnetic resonance (MR) imaging and CT scanning. The abnormalities imaged included 11 arachnoid cysts, 10 cystic tumors, six postoperative cysts, and three colloid cysts. The intensity patterns of the cyst contents as encoded with routine spin-echo imaging sequences enabled subdivision of the cysts into three categories. Arachnoid and postoperative cysts had an intensity pattern identical to cerebrospinal fluid. More proteinaceous cysts, including inflammatory cysts and nonhemorrhagic tumoral cysts, had an intermediate intensity pattern with characteristically low intensity on the short TR sequence (0.5 sec), but had clearly higher intensity than cerebrospinal fluid on the long TR sequences (2 sec). Finally, three cystic tumors with hemorrhagic fluid and three colloid cysts had a distinctly different pattern of high intensity on all four MR sequences through the same section. MR was superior to CT in characterizing intracranial cystic lesions because of its ability to categorize cysts into these three groups on the basis of the intensity pattern of cyst contents, thereby improving diagnostic specificity and patient management.  相似文献   
99.
Loss-of-function variants in ANKRD11 were identified as the cause of KBG syndrome, an autosomal dominant syndrome with specific dental, neurobehavioural, craniofacial and skeletal anomalies. We present the largest cohort of KBG syndrome cases confirmed by ANKRD11 variants reported so far, consisting of 20 patients from 13 families. Sixteen patients were molecularly diagnosed by Sanger sequencing of ANKRD11, one familial case and three sporadic patients were diagnosed through whole-exome sequencing and one patient was identified through genomewide array analysis. All patients were evaluated by a clinical geneticist. Detailed orofacial phenotyping, including orthodontic evaluation, intra-oral photographs and orthopantomograms, was performed in 10 patients and revealed besides the hallmark feature of macrodontia of central upper incisors, several additional dental anomalies as oligodontia, talon cusps and macrodontia of other teeth. Three-dimensional (3D) stereophotogrammetry was performed in 14 patients and 3D analysis of patients compared with controls showed consistent facial dysmorphisms comprising a bulbous nasal tip, upturned nose with a broad base and a round or triangular face. Many patients exhibited neurobehavioural problems, such as autism spectrum disorder or hyperactivity. One-third of patients presented with (conductive) hearing loss. Congenital heart defects, velopharyngeal insufficiency and hip anomalies were less frequent. On the basis of our observations, we recommend cardiac assessment in children and regular hearing tests in all individuals with a molecular diagnosis of KBG syndrome. As ANKRD11 is a relatively common gene in which sequence variants have been identified in individuals with neurodevelopmental disorders, it seems an important contributor to the aetiology of both sporadic and familial cases.  相似文献   
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