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81.
Individual variation in nutritional status has direct implications for fitness and thus is crucial in shaping patterns of life-history variation. Nevertheless, it is difficult to measure in natural populations, especially in humans. Here, we used longitudinal data on individual life-histories and annual crop yield variation collected from pre-industrial Finnish populations experiencing natural mortality and fertility to test the validity of first birth interval (FBI; time between marriage and first birth) as a surrogate measure of nutritional status. We evaluated whether women with different socio-economic groups differ in length of FBI, whether women of poorer socio-economic status and experiencing lower crop yields conceive slower following marriage, and whether shorter FBI is associated with higher lifetime breeding success. We found that poorer women had longer FBI and reduced probability of giving birth in months with low food availability, while the FBI of richer women was not affected by variation in food availability. Women with shorter FBI achieved higher lifetime breeding success and a faster reproductive rate. This is, to our knowledge, the first study to show a direct relationship between environmental conditions and speed of childbirth following marriage, highlighting the value of FBI as an indicator of nutritional status when direct data are lacking.  相似文献   
82.
A rapid, isocratic high-performance liquid chromatographic (HPLC) method is described for the determination of total homocysteine levels in human serum. Prior to reversed-phase HPLC analysis, the serum thiols were derivatized with SBD-F (ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulphonate), a thiol-specific fluorogenic probe which is commercially available. Retention of SBD-homocysteine was sensitive to pH, and a mobile phase pH of 2.1 ensured baseline separation of serum thiols within 6 min. The method is simple, sensitive, reproducible (between-run coefficient of variation of 6.6%) and very suitable for routine determination of serum homocysteine levels in a clinical pathology laboratory.  相似文献   
83.
Summary Activities of the microvillar enzymes -glutamyl-transpeptidase (GGTP), aminopeptidase M (APM), phosphodiesterase and maltase have been examined in second-trimester amniotic fluid as possible aids to the early prenatal diagnosis of cystic fibrosis (CF). The two peptidases, GGTP and APM, gave best results. If the fifth percentile of the normal range is used as an action line, the sensitivity of a positive test (low GGTP value) is 78% and the predictability 84%. At the tenth percentile the sensitivity is 100% and the predictability 77%. These approximate figures apply only to pregnancies where there has been a previous affected child. Until the primary protein defect in CF is discovered, this may prove an acceptable form of prenatal diagnosis to the high-risk mother.  相似文献   
84.
Benign prostatic hyperplasia (BPH) and prostate carcinoma (CaP) are linked to aging and the presence of androgens, suggesting that androgen regulated genes play a major role in these common diseases. Androgen regulation of prostate growth and development depends on the presence of intact epithelial-stromal interactions. Further, the prostatic stroma is implicated in BPH. This suggests that epithelial cell lines are inadequate to identify androgen regulated genes that could contribute to BPH and CaP and which could serve as potential clinical biomarkers. In this study, we used a human prostate xenograft model to define a profile of genes regulated in vivo by androgens, with an emphasis on identifying candidate biomarkers. Benign transition zone (TZ) human prostate tissue from radical prostatectomies was grafted to the sub-renal capsule site of intact or castrated male immunodeficient mice, followed by the removal or addition of androgens, respectively. Microarray analysis of RNA from these tissues was used to identify genes that were; 1) highly expressed in prostate, 2) had significant expression changes in response to androgens, and, 3) encode extracellular proteins. A total of 95 genes meeting these criteria were selected for analysis and validation of expression in patient prostate tissues using quantitative real-time PCR. Expression levels of these genes were measured in pooled RNAs from human prostate tissues with varying severity of BPH pathologic changes and CaP of varying Gleason score. A number of androgen regulated genes were identified. Additionally, a subset of these genes were over-expressed in RNA from clinical BPH tissues, and the levels of many were found to correlate with disease status. Our results demonstrate the feasibility, and some of the problems, of using a mouse xenograft model to characterize the androgen regulated expression profiles of intact human prostate tissues.  相似文献   
85.
86.
Objective To estimate the prevalence of mental capacity to make decisions on treatment in people from different diagnostic and legal groups admitted to psychiatric hospital.Design Cross sectional study.Setting General adult acute psychiatric inpatient units.Participants 350 consecutive people admitted to psychiatric wards from the community over 16 months.Main outcome measure Mental capacity assessed by clinical interview and the MacArthur competence assessment tool for treatment.Results Estimates of mental capacity were obtained on 97% (n=338) of the 350 people admitted. Of those an estimated 60% (95% confidence interval 55% to 65%) lacked mental capacity to make decisions on treatment. This proportion varied according to diagnosis, ranging from 97% (n=36) in people with mania to 4% (n=24) in people with personality disorder. Mental incapacity was common in patients admitted informally to the psychiatric wards (n=188; 39%, 32% to 46%). Incapacity and detention are closely associated under non-capacity based mental health law.Conclusions Mental incapacity to make decisions on treatment is common in people admitted to psychiatric wards from the community but cannot be presumed. It is usual in those detained under the Mental Health Act and common in those admitted voluntarily.  相似文献   
87.

Background  

The coral skeleton consists of CaCO3 deposited upon an organic matrix primarily as aragonite. Currently galaxin, from Galaxea fascicularis, is the only soluble protein component of the organic matrix that has been characterized from a coral. Three genes related to galaxin were identified in the coral Acropora millepora.  相似文献   
88.
We have determined the nucleotide sequences of two independent DNA clones which contained the activated c-myc genes from avian leukosis virus-induced B-cell lymphomas. Neither of these c-myc genes contained missense mutations. This strongly supports the notion that the c-myc proto-oncogene in avian leukosis virus-induced B-cell lymphomas can be oncogenically activated by altered expression of the gene without a change in the primary structure of the gene product.  相似文献   
89.
Kaposi's sarcoma (KS)-associated herpesvirus or human herpesvirus 8 (HHV8) DNA is found consistently in nearly all classical, endemic, transplant, and AIDS-associated KS lesions, as well as in several AIDS-associated lymphomas. We have previously sequenced the genes for the highly variable open reading frame K1 (ORF-K1) protein from more than 60 different HHV8 samples and demonstrated that they display up to 30% amino acid variability and cluster into four very distinct evolutionary subgroups (the A, B, C, and D subtypes) that correlate with the major migrationary diasporas of modern humans. Here we have extended this type of analysis to six other loci across the HHV8 genome to further evaluate overall genotype patterns and the potential for chimeric genomes. Comparison of the relatively conserved ORF26, T0.7/K12, and ORF75 gene regions at map positions 0. 35, 0.85, and 0.96 revealed typical ORF-K1-linked subtype patterns, except that between 20 and 30% of the genomes analyzed proved to be either intertypic or intratypic mosaics. In addition, a 2,500-bp region found at the extreme right-hand side of the unique segment in 45 HHV8 genomes proved to be highly diverged from the 3,500-bp sequence found at this position in the other 18 HHV8 genomes examined. Furthermore, these previously uncharacterized "orphan" region sequences proved to encompass multiexon latent-state mRNAs encoding two highly diverged alleles of the novel ORF-K15 protein. The predominant (P) and minor (M) forms of HHV8 ORF-K15 are structurally related integral membrane proteins that have only 33% overall amino acid identity to one another but retain conserved likely tyrosine kinase signaling motifs and may be distant evolutionary relatives of the LMP2 latency protein of Epstein-Barr virus. The M allele of ORF-K15 is also physically linked to a distinctive M subtype of the adjacent ORF75 gene locus, and in some cases, this linkage extends as far back as the T0.7 locus also. Overall, the results suggest that an original recombination event with a related primate virus from an unknown source introduced exogenous right-hand side ORF-K15(M) sequences into an ancient M form of HHV8, followed by eventual acquisition into the subtype C lineage of the modern P-form of the HHV8 genome and subsequent additional, more recent transfers by homologous recombination events into several subtype A and B lineages as well.  相似文献   
90.
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