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181.
To investigate the relationship between the presence of language disorder, type of epilepsy, and epileptic seizures in childhood, language levels, types of language impairment, and aetiologies were examined in 109 children, aged between 5 and 17 years, attending a national children's epilepsy assessment unit over a 4-year period. There were 70 males and 39 females. Median age was 11 years 4 months (range 5 to 18 years 9 months). In addition to neurological assessment, simultaneous video and EEG monitoring and prolonged ambulatory EEG, each child underwent a comprehensive series of multidisciplinary tests, including intelligence, language, and communication assessments. Classification of seizures and epilepsy syndromes was agreed in conference by a physician specializing in childhood epilepsies, a paediatric neurologist, and a neuropsychiatrist. Other test procedures were administered by a speech and language pathologist with assistance from a neuropsychologist when relevant. Level of language disability in these children was associated with a range of aetiological factors. Evidence was found of a significant number of associations between focal epilepsies, certain seizure types, and language disorder. Of the 46 (42.2%) children with language disorders in the research sample, 30 had localization-related epilepsies and a further three had epilepsies which were undetermined as to whether focal or generalized. Children with focal epilepsies were 30% more likely to have language disorder than other language disability subtypes. The research demonstrated a clear though often subtle association between focal (localization-related) epilepsy and language disorder, indicating an increased risk in this patient group. Children with simple or complex partial seizures were more likely to have language disorder than other language disability subtypes; they also tended to have the lowest number of seizure types per case. This is of importance to clinicians managing children with epilepsy and has implications for their educational and social welfare.  相似文献   
182.
The involvement of mesoaccumbens dopamine in adaptive learning and behaviour is unclear. For example, dopamine may act as a teaching signal to enable learning, or more generally modulate the behavioural expression, or selection, of an already-learned response. The present study investigated the involvement of the mesoaccumbens dopamine system in a fundamental form of learning: Pavlovian conditioning. In this case, the temporal association of a previously neutral visual stimulus and a biologically significant unconditioned stimulus (US), subsequently led to the production of the conditioned response (CR) of discriminated approach behaviour directed toward the conditioned stimulus (CS+), relative to a control (CS-) stimulus. 6-hydroxydopamine lesions of the nucleus accumbens (NAcc), leading to approximately 80% reductions in tissue dopamine, were made at varying time points in four experimental groups of rats, either before or subsequent to the acquisition of the CR. NAcc dopamine depletion produced long-term neuroadaptations in dopamine function 2 months after surgery, and profoundly impaired discriminated Pavlovian approach regardless of when the lesion was made. Thus, NAcc dopamine not only plays a role in conditioned behavioural activation, but also in making the appropriate discriminated response i.e. the direction of response. Further, acquisition lesions produced a far greater impact on discriminated approach than performance lesions. This difference in lesion-induced impairment implies that mesoaccumbens dopamine may play differential roles in the learning and performance of preparatory Pavlovian conditioning.  相似文献   
183.
An understanding of the events that occur during GH receptor (GHR) signaling has facilitated the development of a GHR antagonist (pegvisomant) for use in humans. This molecule has been designed to compete with native GH for the GHR and to prevent its proper or functional dimerization-a process that is critical for GH signal transduction and IGF-I synthesis and secretion. Clinical trials in patients with acromegaly show GHR blockade to be an exciting new mode of therapy for this condition, and pegvisomant may have a therapeutic role in diseases, such as diabetes and malignancy, in which abnormalities of the GH/IGF-I axis have been observed. This review charts the discovery and development of GHR antagonists and details the experience gained in patients with acromegaly.  相似文献   
184.
OBJECTIVE; To determine whether anterior prostatic tumours are adequately sampled using the Stamey sextant protocol, as a fifth of prostate cancers are anterior in distribution at radical prostatectomy. MATERIALS AND METHODS: All tumours (62) with an anterior distribution (>or=75% of the tumour anterior to the urethra) on radical prostatectomy whole-mounts, and in which the number and results of the sextant biopsies were available, were extracted from a prostate cancer database. Sixty-one posterior tumours (>or=75% of the malignant tissue posterior to the urethra) and their corresponding sextant biopsies were also retrieved for comparison. The number of biopsy sessions, the number of cores involved and the summated tumour length were recorded, together with the prostate gland weight, the tumour volume and the site of >or=75% of tumour in the superior-inferior axis. RESULTS: Anterior tumours required significantly more biopsy sessions to diagnose prostate cancer than posterior neoplasms (anterior, one set 47; > one set 15; posterior, one set 57; > one set, four, P=0.007). Anterior tumours had fewer cores with tumour involvement and less summated tumour length than had posterior cancers. The mean (sd) number of positive cores was; anterior 1.8 (1.01), posterior 2.50 (1.30) (P=0.001); the summated tumour length was; anterior 5.05 (4.10) mm, posterior 9.25 (7.80) mm (P<0.001). There was no significant difference in gland weight (mean anterior 43.8 g; posterior 48.3 g, P=0.3) or tumour volume (mean anterior 1.85 mL; posterior 1.49 mL, P=0.11) between the groups. There was no significant difference between the incidence of anterior and posterior neoplasms with respect to their position in the superior-inferior axis (P=0.96). CONCLUSIONS: Anterior prostate tumours account for 21% of all prostate cancers. They more often require multiple sets of sextant biopsies for diagnosis, and yield smaller areas of cancer on core biopsies than do posterior tumours in glands of similar weight and tumour volume. If prostate cancer is suspected clinically but biopsies are negative, targeting the anterior gland at subsequent prostatic biopsy should be considered.  相似文献   
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Topotecan (1.5 mg/m(2)/day for 5 consecutive days of a 21-day cycle) is an established recurrent ovarian cancer treatment, but myelosuppression can be dose limiting. This study evaluates the activity and tolerability of low-dose topotecan in our clinical experience. Case records were reviewed for patients with recurrent ovarian cancer in first through third relapse. Eligible patients had received > or =2 cycles of < or =1.25 mg/m(2) topotecan. Adverse events were evaluated using laboratory and clinical evaluation data. Twenty-seven eligible patients, most with advanced disease, received a total of 209 cycles (median, six cycles). Grade 3 or 4 hematologic toxicities during 184 cycles in 24 assessed patients were neutropenia, leukopenia, thrombocytopenia, and anemia in 35%, 28%, 36%, and 11% of cycles, and 21, 19, 16, and 10 patients, respectively. Only four grade 4 toxicities occurred: anemia (one) and thrombocytopenia (three). Myelosuppression was reversible, noncumulative, and manageable. Moreover, nonhematologic toxicity was generally mild to moderate, and the only two grade 3 events were constipation and deep vein thrombosis. Low-dose topotecan was active in this setting. Lower-dose topotecan is generally well tolerated and active in patients with pretreated ovarian cancer. Prospective clinical trials of low-dose topotecan in recurrent ovarian cancer are warranted.  相似文献   
187.
The past 30 years have witnessed a major paradigm shift in brain tumor research with the development of a wide variety of molecular  相似文献   
188.
Leiomyoma of the vagina is a very rare tumour of the lower urogenital tract. These slow‐growing masses may be asymptomatic or present with pain, dyspareunia or urinary symptoms. Rarely, these tumours may present with life‐threatening haemorrhage. These hypervascular tumours are treated by surgical excision. Preoperative embolization therefore may aid in devascularization of these tumours before surgical excision. We present the MRI features of a case of vaginal leiomyoma, which was managed by preoperative embolization and was then excised in toto. To the best of our knowledge, this is the first report where preoperative embolization was performed before excision of a vaginal leiomyoma with minimal peroperative blood loss.  相似文献   
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