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51.
We previously reported an association of DRD4 exon 3 long alleles with delusional symptomatology, independently from psychiatric diagnoses [Am. J. Med. Genet. 105 (2001) 283; Psychiatry Res. 80 (1998) 129]. The aim of this investigation was to replicate these results in an independent sample from Germany. We studied 394 subjects, affected by bipolar disorder (n = 32), schizoaffective disorder (n = 45), and schizophrenia (n = 317). All affected subjects were evaluated using the Operational Criteria for Psychotic Illness (OPCRIT) checklist. DRD4 variants were not associated with symptomatology of major psychosis. Our present results, obtained in an independent German sample, did not confirm the association between DRD4 variants and delusional symptomatology. However it should be considered that the original sample included a much higher rate of mood disorders and this could partially explain the discrepancy.  相似文献   
52.
BACKGROUND: Patients with familial adenomatous polyposis have a nearly 100 percent risk of colorectal cancer. In this disease, the chemopreventive effects of nonsteroidal antiinflammatory drugs may be related to their inhibition of cyclooxygenase-2. METHODS: We studied the effect of celecoxib, a selective cyclooxygenase-2 inhibitor, on colorectal polyps in patients with familial adenomatous polyposis. In a double-blind, placebo-controlled study, we randomly assigned 77 patients to treatment with celecoxib (100 or 400 mg twice daily) or placebo for six months. Patients underwent endoscopy at the beginning and end of the study. We determined the number and size of polyps from photographs and videotapes; the response to treatment was expressed as the mean percent change from base line. RESULTS: At base line, the mean (+/-SD) number of polyps in focal areas where polyps were counted was 15.5+/-13.4 in the 15 patients assigned to placebo, 11.5+/-8.5 in the 32 patients assigned to 100 mg of celecoxib twice a day, and 12.3+/-8.2 in the 30 patients assigned to 400 mg of celecoxib twice a day (P=0.66 for the comparison among groups). After six months, the patients receiving 400 mg of celecoxib twice a day had a 28.0 percent reduction in the mean number of colorectal polyps (P=0.003 for the comparison with placebo) and a 30.7 percent reduction in the polyp burden (the sum of polyp diameters) (P=0.001), as compared with reductions of 4.5 and 4.9 percent, respectively, in the placebo group. The improvement in the extent of colorectal polyposis in the group receiving 400 mg twice a day was confirmed by a panel of endoscopists who reviewed the videotapes. The reductions in the group receiving 100 mg of celecoxib twice a day were 11.9 percent (P=0.33 for the comparison with placebo) and 14.6 percent (P=0.09), respectively. The incidence of adverse events was similar among the groups. CONCLUSIONS: In patients with familial adenomatous polyposis, six months of twice-daily treatment with 400 mg of celecoxib, a cyclooxygenase-2 inhibitor, leads to a significant reduction in the number of colorectal polyps.  相似文献   
53.
L1 is a neural cell adhesion molecule mainly involved in axon guidance and neuronal migration during brain development. Mutations in the human L1 gene give rise to a complex clinical picture, with mental retardation, neurologic abnormalities and a variable degree of hydrocephalus. Recently, a transgenic mouse model with a targeted null mutation in the L1 gene was generated. These knockout (KO) mice show hypoplasia of the corticospinal tract. Here we have performed further studies of these KO mice including magnetic resonance imaging of the brain, neuropathological analysis and behavioral testing. The ventricular system was shown to be abnormal with dilatation of the lateral ventricles and the 4th ventricle, and an altered shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the KO mice is hypoplastic. Their exploratory behavior is characterized by stereotype peripheral circling reminiscent of that of rodents with induced cerebellar lesions.   相似文献   
54.
The masseter muscle is innervated by branches of 3 nerves. The zygomaticomandibular muscle must be regarded as part of the masseter as it is supplied by 2 branches of the massetericus nerve. Two branches of the medial pterygoid nerve enter the medial pterygoid muscle medially. The lateral pterygoid muscle is supplied by the lateral pterygoid nerve, which enters the muscle dorsally perpendicular to the muscle fibres. Five branches of the profound temporal nerves enter the temporal muscle from the ventral and medial sides. The branches of all nerves proceed parallel to each other in the dorsal direction towards the origin of the muscle.  相似文献   
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56.
We undertook to determine whether previous exposure in the nest is necessary to establish the attractiveness of the maternal pheromone or whether that attractiveness is innately based. In Experiment 1 we showed that the pheromone is a prepotent stimulus insofar as it is approached in preference to a different but equally familiar odor. Experiment 2 demonstrated that when pups are denied previous exposure to the pheromone they nonetheless approach the pheromone preferentially in a choice test involving a pheromone-emitting and a non-pheromone-emitting female. And finally, in Experiment 3, we again used pups that had been isolated from the pheromone. Here, however, the choice was between a pheromone-emitting female and a female which, while non-pheromone-emitting, carried a thoroughly familiar nest odor. The pups decisively chose the pheromone-emitting female. We conclude that pheromonal attractiveness is innately based and suggest that the pheromone itself may have been selected as a signal during the course of evolution.  相似文献   
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58.
The transformation of the health care delivery system in local, metropolitan, and regional markets is progressing rapidly. This transformation is fueled by competition, the shift of financial risk to the provider continuum, employer demands for cost containment, and the breadth and depth of state and federal government reform initiatives. However, information systems do not yet exist to support these transformations. We propose establishing a new community-level information management environment and new measures of health care system performance.  相似文献   
59.
Background: In the early 1980s breast preservation was a rarely applied therapeutic modality in the primary treatment of breast cancer in the Federal Republic of Germany. Reports coming from retrospective studies as well as preliminary results from randomized trials made it desirable to introduce breast preservation in the form of a controlled clinical trial. Study design: In stage pT1 N0 M0 breast cancer, mastectomy as the standard treatment was to be compared with radiotherapy of the remaining breast tissue. The study design originally planned as a randomized trial had to be changed into a prospective observation study due to the low randomization rate. Univariate analysis of prognostic variables was the first step to a valid treatment comparison. Those factors determined as being significant were included together with the treatment effects in a multivariate analysis. A high therapeutic standard was guaranteed by quality control. Results: 1036 out of 1119 recruited patients are evaluable. After a median follow-up of 48 months the following preliminary results can be reported. With the exception of death without recurrence from breast cancer, the 143 events are evenly distributed among the two treatment groups. Locoregional recurrence of the whole patient population was 5%. Out of all prognostic factors examined only tumor size and grading are significant in regard to recurrent disease. Recurrence-free survival decreased in cases with uncertain tumor margins, whereas the width of the margin had no influence on recurrent disease. There was no significant difference in quality of life between the two treatment groups. Conclusions: The four-year results of this study are in accordance with those of other breast preservation trials: There is no significant difference between the two treatment groups in the occurrence of locoregional failure. Incomplete tumorectomy has a negative influence on recurrence. Quality of life seems more dependent on the acceptance of the therapy by the patient than on the therapeutic modality itself. Breast preservation can also be performed appropriately in smaller institutions if the therapeutic standard is guaranteed by quality control.This study was sponsored by the Ministry of Research and Technology (BMFT) of the Federal Republic of Germany.  相似文献   
60.
Pure word deafness (auditory verbal agnosia) is characterized by an impairment of auditory comprehension, repetition of verbal material and writing to dictation whereas spontaneous speech production and reading largely remain unaffected. Sometimes, this syndrome is preceded by complete deafness (cortical deafness) of varying duration. Perception of vowels and suprasegmental features of verbal utterances (e.g., intonation contours) seems to be less disrupted than the processing of consonants and, therefore, might mediate residual auditory functions. Often, lip reading and/or slowing of speaking rate allow within some limits to compensate for speech comprehension deficits. Apart from a few exceptions, the available reports of pure word deafness documented a bilateral temporal lesion. In these instances, as a rule, identification of nonverbal (environmental) sounds, perception of music, temporal resolution of sequential auditory cues and/or spatial localization of acoustic events were compromised as well. The observed variable constellation of auditory signs and symptoms in central hearing disorders following bilateral temporal disorders, most probably, reflects the multitude of functional maps at the level of the auditory cortices subserving, as documented in a variety of non-human species, the encoding of specific stimulus parameters each. Thus, verbal/nonverbal auditory agnosia may be considered a paradigm of distorted "auditory scene analysis" (Bregman 1990) affecting both primitive and schema-based perceptual processes. It cannot be excluded, however, that disconnection of the Wernicke-area from auditory input (Geschwind 1965) and/or an impairment of suggested "phonetic module" (Liberman 1996) contribute to the observed deficits as well. Conceivably, these latter mechanisms underly the rare cases of pure word deafness following a lesion restricted to the dominant hemisphere. Only few instances of a rather isolated disruption of the discrimination/identification of nonverbal sound sources, in the presence of uncompromised speech comprehension, have been reported so far (nonverbal auditory agnosia). As a rule, unilateral right-sided damage has been found to be the relevant lesion.  相似文献   
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