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101.
We report that eight patients from France, Italy, and Thailand had serological evidence of Rickettsia helvetica infection. The infection presented as a mild disease in the warm season and was associated with fever, headache, and myalgia but not with a cutaneous rash. R. helvetica should be suspected in patients with unexplained fever, especially following a bite from an Ixodes sp. tick.  相似文献   
102.
Aggressive behaviors were compared for male Fischer-344 and Long-Evans rats formed into mixed-sex colonies at 100, 200, or 300 days of age. Within each strain, male aggression did not differ across these ages, nor did it differ for an additional group of 600-day old Long-Evans males: both the form and the incidence of specific aggressive and defensive behaviors remained relatively constant over an age range representing nearly the entire normal life span for this species. However, Fischer-344 males at all ages were reliably lower in aggression than the Long-Evans rats. The specific aggression components seen in the Fischer-344 rats tended to be nondamaging, resembling “play fighting” more than the tissue damaging attack behaviors typical of other strains. Despite the frequent use of this strain in gerontological research, such low levels of aggressiveness counterindicate their use in research in aging and aggression.  相似文献   
103.
High risk pregnancies in hypopituitary women   总被引:1,自引:0,他引:1  
BACKGROUND: Various short papers have suggested that pregnancies in women with hypopituitarism are high risk but no formal assessment of pregnancy outcome has yet been reported. METHODS: An audit was carried out concerning the outcome of 18 pregnancies in nine women who underwent ovulation induction in a single centre over 20 years. RESULTS: The live birth rate was 61%, miscarriage rate 28% and mid-trimester uterine death rate 11% with no survivors from four sets of twins. The Caesarian section rate was 100% and half of the live births were on or below the 10th centile for weight. One woman successfully breast-fed. CONCLUSIONS: Women with hypopituitarism have high-risk pregnancies, perhaps because of a uterine defect secondary to endocrine deficiency. Fertility treatment must strive for singleton pregnancies with application of particularly strict criteria to avoid twin pregnancies. Early elective Caesarian section is probably warranted in this group.  相似文献   
104.
In October 2001, a letter containing a large number of anthrax spores was sent through the Brentwood post office in Washington, D.C., to a United States Senate office on Capitol Hill, resulting in contamination in both places. Several thousand people who worked at these sites were screened for spore exposure by collecting nasal swab samples. We describe here a screening protocol which we, as a level A laboratory, used on very short notice to process a large number of specimens (3,936 swabs) in order to report preliminary results as quickly as possible. Six isolates from our screening met preliminary criteria for Bacillus anthracis identification and were referred for definitive testing. Although none of the isolates was later confirmed to be B. anthracis, we studied these isolates further to define their biochemical characteristics and 16S rRNA sequences. Four of the six isolates were identified as Bacillus megaterium, one was identified as Bacillus cereus, and one was an unidentifiable Bacillus sp. Our results suggest that large-scale nasal-swab screening for potential exposure to anthrax spores, particularly if not done immediately postexposure, may not be very effective for detecting B. anthracis but may detect a number of Bacillus spp. that are phenotypically very similar to B. anthracis.  相似文献   
105.
Familial hypercholesterolaemia (FH) is a common inherited disorder, associated with premature vascular disease. FH may be caused by many different mutations in the low density lipoprotein receptor (LDLR) gene, about 700 mutations have been described, most of which occur rarely and often only in single families. Although particular mutations are prevalent in certain ethnic groups, countries with heterogeneous population bases (such as NZ) may carry a wide variety of mutations; making a gene screening approach the appropriate first step for a mutation detection programme. We have compared SSCP with DHPLC to assess their effectiveness as methods for LDLR mutation detection. Although five novel LDLR mutations were detected by SSCP in patients with FH, DHPLC was more sensitive, with eight novel mutations detected. Six of these mutations (T392M, R419G, Y421N, 1206-1207delCT, 1872delC, and 1943delC) were clustered in exons 9 and 13 of the EGF precursor homology domain, one (679-680delAC) in the ligand binding domain (exon 4) and the eighth (P774H) in the membrane-spanning domain (exon 16). Twenty five mutations were identified in 35 patients in total. Of these, we were able to detect only 64% of mutations by SSCP even though all variants were detected by DHPLC. All patients are heterozygous for the mutations, which is consistent with the clinical phenotypes.  相似文献   
106.
We report the identification of mutations in lipoxygenase-3 (ALOXE3) and 12(R)-lipoxygenase (ALOX12B) genes in non-bullous congenital ichthyosiform erythroderma (NCIE) linked to chromosome 17. Linkage disequilibrium analysis of six families affected by NCIE permitted us to reduce a recently reported interval of 8.4 cM on chromosome 17p13.1 to a 600 kb region around the marker D17S1796, which contains LOX genes. LOX products have long been implicated in skin disorders. Two point mutations and one deletion were found in ALOXE3 and three point mutations were found in ALOX12B in these consanguineous families from the Mediterranean basin. ALOXE3 and ALOX12B are two genes which are physically linked and functionally related. They are separated by 38 kb, have one more exon than the other LOX genes and are mainly expressed in epithelial cells including keratinocytes. Although the main substrate(s) of the two enzymes is (are) still unknown, the products of ALOX12B obtained in experimental systems have been demonstrated to be of R-chirality. It seems likely that the product of one of these enzymes may be the substrate of the other, and that they belong to the same metabolic pathway.  相似文献   
107.
To date, only one complete genome screen for obsessive-compulsive disorder (OCD) has been published. That study identified a region of suggestive linkage (maximum lod score of 2.25) with a relatively small sample size (N = 56; 27 with OCD). Additional complete genome screens are needed to confirm this finding and identify other regions of linkage. We present the clinical characteristics and power to detect linkage of 11 multigenerational families with OCD and hoarding (N = 92; 44 with OCD), as well as heritability estimates for several quantitative traits. Families with at least two individuals with OCD were identified through probands with childhood-onset OCD. Expected lod scores were calculated for simulated genetic marker data under an additive and two dominant models assuming a dense SNP marker map. All affected individuals had an early age of onset (18 or younger). Hoarding was present in 46% of subjects. Obsessive-compulsive symptoms and hoarding were highly heritable. The maximum mean expected lod score was 3.31 for OCD and 1.39 for hoarding. We found reasonable power to detect regions of interest (lod = 2) for OCD in these families, but will need to expand our family collection to have adequate power to detect regions of interest for hoarding.  相似文献   
108.
Prenatal trisomy 7 is usually a cell culture artifact in amniocytes with normal diploid karyotype at birth and normal fetal outcome. In the same way, true prenatal trisomy 7 mosaicism usually results in a normal child except when trisomic cells persist after birth or when trisomy rescue leads to maternal uniparental disomy, which is responsible for 5.5-7% of patients with Silver-Russell syndrome (SRS). We report here on the unusual association of SRS and Hirschsprung's disease (HSCR) in a patient with maternal uniparental heterodisomy 7 and trisomy 7 mosaicism in intestine and skin fibroblasts. HSCR may be fortuitous given its frequency, multifactorial inheritance and genetic heterogeneity. However, the presence of the trisomy 7 mosaicism in intestine as well as in skin fibroblasts suggests that SRS and HSCR might possibly be related. Such an association might result from either an increased dosage of a nonimprinted gene due to trisomy 7 mosaicism in skin fibroblasts (leading to SRS) and in intestine (leading to HSCR), or from an overexpression, through genomic imprinting, of maternally expressed imprinted allele(s) in skin fibroblasts and intestine or from a combination of trisomy 7 mosaicism and genomic imprinting. This report suggests that the SRS phenotype observed in maternal uniparental disomy 7 (mUPD(7)) patients might also result from an undetected low level of trisomy 7 mosaicism. In order to validate this hypothesis, we propose to perform a conventional and molecular cytogenetic analysis in different tissues every time mUPD7 is displayed.  相似文献   
109.

Background  

The increasing use of complementary and alternative medicines in Australia has generated concern regarding the information on these products available to both healthcare providers and the public. The aim of this study was to examine the practice behaviours of naturopaths in relation to both the provision of and access to information on complementary and alternative medicines (CAM).  相似文献   
110.
Vascular dementia appears rarer than previously thought, but the contribution of vascular lesions to cognitive impairment in Alzheimer's disease (AD) affected patients (mixed dementias) is now recognized as frequent. The role of strategic areas of the brain involved in the cognitive decline induced by vascular lesions and their relative contributions to the severity of the dementing process remain poorly understood. We determined the relationship between the severity of clinical dementia and the volume of different brain areas affected by infarcts in a prospective clinicopathological study in elderly patients. A volumetric study of the functional zones of Mesulam's human brain map affected by vascular lesions was made and correlations between quantified neuropathological data and the severity of dementia were performed in cases with large vascular lesions only, pure AD, and both lesions. The severity of cognitive impairment was significantly correlated with the total volume of infarcts but in a multi-variate model the volume destroyed in the limbic and heteromodal association areas, including the frontal cortex and in the white matter explained 50% of the variability in MMSE and GDS. The total volume of ischemic lesions explained only 0.1-5% of the variability in MMSE and GDS. Age only explained an extra of 0.1-1.6%. This study confirms that infarcts located in strategic areas have a role in the mechanism of cognitive impairment and brings a key for their quantification. It may be useful for developing neuropathological criteria in multi-infarct and mixed dementias.  相似文献   
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