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1.
Bo Sikström M.D. Dan Hellberg M.D. Ph.D. Staffan Nilsson M.D. Ph.D. Christina Brihmer M.D. Ph.D. Per-Anders Mårdh M.D. Ph.D. 《Archives of sexual behavior》1996,25(4):361-372
In a study of 972 women, sexual characteristics of 66 women with a cervical human papillomavirus infection (CHPI) were compared
to the remaining study population. Among a number of sexual variables that were significantly correlated with CHPI were number
of lifetime sexual partners, short partnerships, many recent partners, infidelity, casual travel sex, sexual début abroad,
oral and anal sex, and sexual abuse. In multifactorial analyses four variables remained significantly correlated with CHPI,
i.e., number of lifetime sexual partners, casual travel sex, sexual début abroad, and infidelity. It is concluded that CHPI
shows most of the epidemiological characteristics of a sexually transmitted disease. 相似文献
2.
Per-Anders Abrahamsson 《European Urology Supplements》2009,8(5):418-423
ContextTo treat or not to treat is one of the most difficult dilemmas facing prostate cancer patients, especially elderly men with early prostate cancer or small cancer that is contained within the prostate.ObjectiveThe primary objective of this review is to analyse the treatment options for patients with localised prostate cancer. This information can be considered alongside other important factors like natural history of disease and diagnostic tests.Evidence acquisitionSeveral randomised and nonrandomised clinical trials published in the literature investigating the natural history of the disease, diagnostic tests, and treatment options for localised prostate cancer have been reviewed for this paper.Evidence synthesisAnalysis of prostate-specific antigen (PSA) kinetics should play a major role in the management of localised prostate cancer. Trials investigating long-term outcomes of active surveillance are under way.ConclusionTaking all these factors into consideration, the data support active surveillance as an appropriate choice for patients with well-differentiated or moderately differentiated, low-volume prostate cancer who have a life expectancy of <10 yr. Men with higher grade tumours and longer life expectancy may be at excess risk of death from prostate cancer if managed with active surveillance. 相似文献
3.
Herpes simplex virus type 1 restriction fragment polymorphism determined using southern hybridization 总被引:2,自引:0,他引:2
Summary Regions of herpes simplex virus type 1 (HSV-1) DNA with variation in the size of restriction endonuclease fragments were identified by comparison of theBam HI,KpnI orSalI restriction endonuclease digestion patterns among 15 HSV-1 isolates after hybridization with specific32P-labeled cloned HSV-1 DNA fragments. Of the types of restriction fragment polymorphism identified, one was a strain with a distinctly different restriction fragment than the prototype (loss or gain of restriction sites). Another type, the specific fragment varied only in size among strains. Thirteen distinct variations were identified. Ten were mapped to the unique sequence of the L component; two to the inverted repeat of the L component and one to the inverted repeat of the S component. The presence of a common ancestor from which some isolates of HSV-1 might derive was deduced from an analysis of the distribution of the thirteen variations among the 15 HSV-1 isolates.With 8 FiguresOn leave from the Chemo-Sero-Therapeutic Institute, Kumamoto, Japan. 相似文献
4.
Kun Sun Jeanette Br?ms Moa Lavander Bharat Kumar Gurram Per-Anders Enquist C. David Andersson Mikael Elofsson Anders Sj?stedt 《Antimicrobial agents and chemotherapy》2014,58(7):4123-4130
The type VI secretion system (T6SS) is the most prevalent bacterial secretion system and an important virulence mechanism utilized by Gram-negative bacteria, either to target eukaryotic cells or to combat other microbes. The components show much variability, but some appear essential for the function, and two homologues, denoted VipA and VipB in Vibrio cholerae, have been identified in all T6SSs described so far. Secretion is dependent on binding of an α-helical region of VipA to VipB, and in the absence of this binding, both components are degraded within minutes and secretion is ceased. The aim of the study was to investigate if this interaction could be blocked, and we hypothesized that such inhibition would lead to abrogation of T6S. A library of 9,600 small-molecule compounds was screened for their ability to block the binding of VipA-VipB in a bacterial two-hybrid system (B2H). After excluding compounds that showed cytotoxicity toward eukaryotic cells, that inhibited growth of Vibrio, or that inhibited an unrelated B2H interaction, 34 compounds were further investigated for effects on the T6SS-dependent secretion of hemolysin-coregulated protein (Hcp) or of phospholipase A1 activity. Two compounds, KS100 and KS200, showed intermediate or strong effects in both assays. Analogues were obtained, and compounds with potent inhibitory effects in the assays and desirable physicochemical properties as predicted by in silico analysis were identified. Since the compounds specifically target a virulence mechanism without affecting bacterial replication, they have the potential to mitigate the virulence with minimal risk for development of resistance. 相似文献
5.
Per-Anders Tengland 《Health care analysis》2012,20(1):66-83
When seeing immoral actions, criminal or not, we sometimes deem the people who perform them unhealthy. This is especially
so if the actions are of a serious nature, e.g. involving murder, assault, or rape. We turn our moral evaluation into an evaluation
about health and illness. This tendency is partly supported by some diagnoses found in the DMS-IV, such as Antisocial personality
disorder, and the ICD-10, such as Dissocial personality disorder. The aim of the paper is to answer the question: How analytically
sound is the inclusion of morality into a theory of health? The holistic theory of Lennart Nordenfelt is used as a starting
point, and it is used as an example of a theory where morality and health are conceptually distinct categories. Several versions
of a pluralistic holistic theory are then discussed in order to see if, and if so, how, morality can be conceptually related
to health. It is concluded that moral abilities (and dispositions) can be seen as being part of the individual’s health. It
is harder to incorporate moral virtues and moral actions into such a theory. However, if immoral actions “cluster” in an individual,
and are of a severe kind, causing serious harm to other people, it is more likely that the person, for those reasons only,
be deemed unhealthy. 相似文献
6.
Inhibition of dipeptidyl peptidase-4 reduces glycemia, sustains insulin levels, and reduces glucagon levels in type 2 diabetes 总被引:26,自引:0,他引:26
Ahrén B Landin-Olsson M Jansson PA Svensson M Holmes D Schweizer A 《The Journal of clinical endocrinology and metabolism》2004,89(5):2078-2084
The stimulation of insulin vs. inhibition of glucagon secretion in relation to the antidiabetic action of glucagon-like peptide-1 (GLP-1) is not established. Here, the influence of a 4-wk increase in circulating GLP-1 by inhibition of dipeptidyl peptidase-4 (DPP-4) on 24-h glucose and insulin and glucagon responses to breakfast was studied in subjects with dietary controlled diabetes [age: 65 +/- 8 yr (SD), body mass index: 27.3 +/- 3.3 kg/m(2), fasting plasma glucose: 9.0 +/- 1.3 mmol/liter]. Compared with placebo (n = 19), a specific DPP-4 inhibitor [(1-[[(3-hydroxy-1-adamantyl) amino] acetyl]-2-cyano-(S)-pyrrolidine) (LAF237); 100 mg daily, n = 18] reduced fasting glucose by 0.70 mmol/liter (P = 0.037), 4-h prandial glucose excursion by 1.45 mmol/liter (P < 0.001), and mean 24-h glucose by 0.93 mmol/liter (P < 0.001). Baseline and postprandial active GLP-1 were increased by LAF237. The glucagon response to breakfast was reduced by LAF237 (glucagon levels at 60 min were 88 +/- 8 pg/ml before treatment vs. 77 +/- 5 pg/ml after; P = 0.001). In contrast, the overall insulin levels were not altered. The 4-wk reduction in glucagon correlated with the reduction in 2-h glucose (r = 0.61; P = 0.008). No such association was observed for insulin. Thus, improved metabolic control by DPP-4 inhibition in type 2 diabetes is seen in association with reduced glucagon levels and, despite the lower glycemia, unaltered insulin levels. 相似文献
7.
Christine Lamanna Benjamin Blonder Cyrille Violle Nathan J. B. Kraft Brody Sandel Irena ?ímová John C. Donoghue II Jens-Christian Svenning Brian J. McGill Brad Boyle Vanessa Buzzard Steven Dolins Peter M. J?rgensen Aaron Marcuse-Kubitza Naia Morueta-Holme Robert K. Peet William H. Piel James Regetz Mark Schildhauer Nick Spencer Barbara Thiers Susan K. Wiser Brian J. Enquist 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(38):13745-13750
The processes causing the latitudinal gradient in species richness remain elusive. Ecological theories for the origin of biodiversity gradients, such as competitive exclusion, neutral dynamics, and environmental filtering, make predictions for how functional diversity should vary at the alpha (within local assemblages), beta (among assemblages), and gamma (regional pool) scales. We test these predictions by quantifying hypervolumes constructed from functional traits representing major axes of plant strategy variation (specific leaf area, plant height, and seed mass) in tree assemblages spanning the temperate and tropical New World. Alpha-scale trait volume decreases with absolute latitude and is often lower than sampling expectation, consistent with environmental filtering theory. Beta-scale overlap decays with geographic distance fastest in the temperate zone, again consistent with environmental filtering theory. In contrast, gamma-scale trait space shows a hump-shaped relationship with absolute latitude, consistent with no theory. Furthermore, the overall temperate trait hypervolume was larger than the overall tropical hypervolume, indicating that the temperate zone permits a wider range of trait combinations or that niche packing is stronger in the tropical zone. Although there are limitations in the data, our analyses suggest that multiple processes have shaped trait diversity in trees, reflecting no consistent support for any one theory.Species richness increases toward the equator (1, 2) in major clades of both extant and extinct species of plants and animals (3, 4). The generality of the pattern hints at a correspondingly general explanation, yet the latitudinal gradient in species richness remains one of ecology’s greatest unsolved puzzles. Long-running debates over the causes of the latitudinal gradient of species richness have focused on ecological, evolutionary, and geographic explanations (5–10). Although there has been some progress (11), it is also increasingly clear that there are numerous obstacles to understanding the primary drivers of the latitudinal gradient, including an ever-increasing number of hypotheses (12, 13), challenges in clearly separating their interdependencies (14, 15), and difficulties in rigorously falsifying their assumptions and predictions (16).More powerful tests of biodiversity theories need to move beyond species richness and instead explicitly focus on the mechanisms generating the gradient, by recasting the theories in terms of other measures of diversity, such as functional diversity (17–19). For example, explanations that assume species richness is limited by resource availability have often focused on the strength of species interactions, life history differences, and environmental constraints on how species pack into niche space (20). Evolutionary hypotheses have focused on differences in diversification rates, as well as the influence of species interactions on diversification rates (9). These interaction-based explanations implicitly refer to the degree of ecological differentiation among species, and therefore to trait dispersion within clades and assemblages, suggesting that patterns of functional diversity may provide a more powerful test of theory than taxonomic richness (21).A particularly important concept that unifies many ecological and evolutionary theories is the concept of the Hutchinsonian multidimensional niche (22). Hutchinsonian niches can be quantified by assessing the functional trait hypervolumes that characterize phenotypic space occupied by a set of species. Quantifying the volume, overlap, and packing of functional trait space at different spatial scales enables inferences about how differing ecological and evolutionary processes structure functional diversity and ecological strategies (23, 24).Here, we recast several contrasting hypotheses for the latitudinal gradient in terms of functional trait space. We focus on the proximate ecological mechanisms that ultimately can influence evolutionary processes. We quantify tree functional trait space across latitude at three spatial scales: (i) within assemblages (alpha), (ii) among assemblages (beta), and (iii) among biomes (gamma). For alpha and beta analyses, we use tree species assemblage data from 620 standardized 0.1-ha forest plots (Fig. 1A); for gamma analyses, we calculated the latitudinal range distributions for 520 New World tree species where we had sufficient data on geographic distribution and functional traits. In total, across all analyses, we used paired geographic occurrence data with trait data for 6,839 tree species.Open in a separate windowFig. 1.(A) Spatial distribution of the 620 0.1-ha forest plots used in this study. Plots are colored by richness. Plots cover most of the New World forested climate space (Fig. S1). (B) Relationship between absolute latitude and alpha hypervolume for tropical (red triangles) and temperate (blue pluses) plots. (C) Alpha hypervolume as a function of effective species richness (number of species with full trait coverage). We compare this hypervolume with a null expectation based on sampling the same number of species from the regional pool (median, dark gray line; 90% quantile range, light gray envelope).We primarily measured hypervolumes for three central traits hypothesized to characterize major axes of ecological strategy variation (25): specific leaf area (SLA), maximum height, and seed mass. SLA represents the tradeoff between leaf longevity and maximum photosynthetic rate (26); height is important for light competition and dispersal (27); and seed mass represents tradeoffs between fecundity, dispersal, and seedling survival (27). Although whole-plant resource strategies can be more fully assessed in higher dimensions (28, 29), we focus on these traits because of data availability (Materials and Methods). We use a hypervolume algorithm for calculating the volume and overlap of trait space (30) (Materials and Methods). All hypervolumes are reported in units of SDs of centered and scaled log-transformed trait values, raised to the power of the number of trait dimensions used.At all scales, our overall results and conclusions are similar (i) with and without gap-filling missing data, (ii) if we use convex hulls instead of hypervolumes to calculate trait spaces, and (iii) if we include additional trait axes. Additional details are given in Figs. S2–S7. 相似文献
8.
Gunilla Maria Olsson Staffan Mårild Jan Alm Ulf Brodin Per-Anders Rydelius Claude Marcus 《Nordic journal of psychiatry》2013,67(1):66-76
Psychosocial development in children with chronic disease is a key issue in paediatrics. This study investigated whether psychosocial adjustment could be reliably assessed with the 42-item Adolescent Adjustment Profile (AAP) instrument. The study mainly focused on adjustment-to-obesity measurement, although it compared three patient groups with chronic conditions. All phenylketonuria (PKU) patients in Sweden between ages 9 and 18 and their parents and teachers were invited to participate. Patients with neurobehavioural syndromes and obesity were age- and gender-matched with PKU patients. Healthy children constituted a reference group. Psychosocial adjustment was measured using the AAP, which is a multi-informant questionnaire that contains four domains. Information concerning parents’ socio-economic and civil status was requested separately. Respondents to the three questionnaires judged the PKU patients to be normal in all four domains. Patients with neurobehavioural syndromes demonstrated less competence and the most problems compared with the other three groups. According to the self-rating, the parent rating and the teacher rating questionnaires, obese patients had internalizing problems. The parent rating and the teacher rating questionnaire scored obese patients as having a lower work capacity than the reference group. Compared with the reference group, not only families with obese children but also families with children with neurobehavioural syndromes had significantly higher divorce rates. Obese patients were also investigated with the Strength and Difficulties Questionnaire (SDQ), another instrument that enables comparison between two measures of adjustment. The AAP had good psychometric properties; it was judged a useful instrument in research on adolescents with chronic diseases. 相似文献
9.
Cloning of integrated Moloney sarcoma proviral DNA sequences in bacteriophage lambda. 总被引:26,自引:13,他引:26 下载免费PDF全文
G F Vande Woude M Oskarsson L W Enquist S Nomura M Sullivan P J Fischinger 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(9):4464-4468
We have identified integrated proviral DNA sequences of m1 and HT-1 isolates of Moloney sarcoma virus (MuSV) in EcoRI digests of transformed mink cell genomic DNA and have cloned these fragments in bacteriophage lambda. Both the lambda-HT1 phage recombinant, containing a 12.3-kilobase MuSV pair (kb) fragment, and the lambda-m1 phage recombinant, containing a 7.0-kb fragment, possess full copies of the sarcoma viruses along with 5' and 3' host flanking sequences. The MuSV proviral DNA sequences, 6.7 kb for HT-1 and 5.2 kb for m1, are colinear by heteroduplex microscopy with the 1.5-kb difference in size accounted for by two approximately equal to 0.8-kb deleted regions in m1. Both integrated viral genomes are terminally redundant and have integrated at the same site in the provirus but at different sites on the host chromosome. The host sequence flanking integrated HT-1 MuSV have been identified as a single EcoRI restriction fragment of 5.6 kb in normal mink cells. 相似文献
10.
Margret Nisell RN Med.Lic.Sci Wilmar Igl PhD Maria Öjmyr-Joelsson RN PhD Björn Frenckner MD PhD Per-Anders Rydelius MD PhD Kyllike Christensson RNM PhD 《Journal of child and adolescent psychiatric nursing》2009,22(3):132-142
PROBLEM: Children with imperforate anus (IA) may be psychosocially affected.
METHODS: Parents of children with IA and parents in two comparison groups rated their children using a study-specific questionnaire and the Competence Scales in the Child Behavior Checklist (CBCL). Teachers rated Academic and Adaptive Functioning Scales in the Teacher's Report Form (TRF).
FINDINGS: School items were rated favorably by the fathers of children with IA, and mothers reported less expression of their children's will. Children with IA were socially competent according to CBCL, although they received lower ratings on the TRF.
CONCLUSIONS: Psychosocial issues seem to be challenging for children with IA, and this needs attention in care management. 相似文献
METHODS: Parents of children with IA and parents in two comparison groups rated their children using a study-specific questionnaire and the Competence Scales in the Child Behavior Checklist (CBCL). Teachers rated Academic and Adaptive Functioning Scales in the Teacher's Report Form (TRF).
FINDINGS: School items were rated favorably by the fathers of children with IA, and mothers reported less expression of their children's will. Children with IA were socially competent according to CBCL, although they received lower ratings on the TRF.
CONCLUSIONS: Psychosocial issues seem to be challenging for children with IA, and this needs attention in care management. 相似文献