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(1) The estrous cycle in the rat may be used to study recurrent changes in motor behaviors and motivation which are strongly related to cyclic hormonal and CNS changes. (2) The peak in motivated behaviors occurs during a sharply defined period on the night between proestrus and estrus and is evident in facilitated wheel-running, lordosis, and intracranial self-stimulation. (3) Behaviors without a clearly motivated character do not show an estrous cyclicity. (4) The estrous cyclic variation in intracranial self-stimulation was observed at a specific locus — the pars campacta of the substantia nigra. (5) A neurochemical link between sexually motivated behavior, wheel running and intracranial self-stimulation is suggested. This link is in part dopaminergic but is probably also activated by many other systems.  相似文献   
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ImmunoCyt/uCyt is a fluorescent test combining three monoclonal antibodies. In this study, it has been tested as a complement to cytology in the detection of urothelial carcinoma in urine. It has been performed simultaneously with standard cytology and cystoscopy on 870 urine analyses from one hospital. In 136 cases, one or more bladder tumors were found. Overall sensitivity of cytology, ImmunoCyt/uCyt and combined analyses reached 29, 74 and 84%, respectively, and overall specificity was 98, 62 and 61%. The negative predictive value of cytology, ImmunoCyt/uCyt and both analyses was 88, 93 and 95%, respectively, and the positive predictive value was 70, 26 and 29%. The sensitivity of cytology for low malignant potential neoplasms, low- and high-grade papillary carcinomas was 6, 18 and 53%, while it reached 71, 79 and 93% when combined with ImmunoCyt/uCyt. The sensitivity of cytology for stages Ta, T1, T2 and over and Tis tumors was 12, 67, 47 and 50%, while it reached 78, 83, 79 and 100% when combined with ImmunoCyt/uCyt. In the absence of tumor on cystoscopy but with positive ImmunoCyt/uCyt, 18% of patients developed a tumor, 2-6 months later. Of the 109 cases diagnosed as suspicious for malignancy by cytology, a tumor was present in 30 cases and ImmunoCyt/uCyt was positive in 22 (73%) of them. In conclusion, ImmunoCyt/uCyt may be used to postpone cystoscopies in patients followed for bladder cancer and may help to save cytologist and pathologist screening time.  相似文献   
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Bernard Gitler 《Journal of nuclear cardiology》2007,14(6):904; author reply 904-904; author reply 905
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A computer-assisted method for the registration of food intakes in real time according to a concise and simple procedure was subjected to a series of controls in order to assess precision. The method employs the 'portion' of a composite dish as unit of measure. The constancy of the portion was tested. The results show that the recipes of the diet of a subject may be stored and utilized in deferred time without loss of precision: data to be recorded in real time are then very limited. The length of period of analysis was also studied. The time of investigation should not be shorter than two weeks to obtain precise information on the feeding habits of an individual subject, whereas for a group of subjects the diary of a single day provides information of sufficient precision.  相似文献   
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Following the well-known European CCRs of Manchester and Turin, 2 regional CCRs have been recently created in France: in Nancy (1983) and Marseille (1984); both are population based CCRs, covering respectively 535,200 and 809,200 children (0-14 yrs). All malignant neoplasms are included, as well as brain tumours (whatever grading) and borderline malignancies. Data are collected from medical and administrative sources. Registration is active and every source is recontacted annually. The registries contact all physicians who might include children among their patients (private and hospital practice), and laboratories of pathology-cytology. The University Hospital Centers and Anti-Cancer Centers in adjacent regions, and in Paris are contacted. Death certificates for children dying of a malignant neoplasm are also sent to the registry. Data collected are as follows: name, age, sex, address, date and method of diagnosis, histological type, anatomical site, stage, treatment and sources of information. We added the data of a general cancer registry, created in Strasbourg in 1975 and covering 205,900 children. reliability of the methodology is attested by the similarity of the results obtained in other European, US and Australian CCRs. In conclusion, this type of registry is needed to organize multicentric epidemiological studies about the role of etiological factors, the survival, and the long term sequelae.  相似文献   
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