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Frequent intrapatient recombination between HIV-1 R5 and X4 envelopes: Implications for coreceptor switch.

Emergence of human immunodeficiency virus type 1 (HIV-1) populations that switch or broaden coreceptor usage from CCR5 to CXCR4 is intimately coupled to CD4(+) cell depletion and disease progression toward AIDS. To better understand the molecular mechanisms involved in the coreceptor switch, we determined the nucleotide sequences of 253 V1 to V3 env clones from 27 sequential HIV-1 subtype B isolat

Cyclic AMP-specific and cyclic GMP-specific phosphodiesterase isoenzymes in human cavernous arteries - immunohistochemical distribution and functional significance

Objectives: It has been well established that male erectile dysfunction is frequently associated with vascular diseases. The normal function of cavernous arteries is considered a prerequisite to maintain sufficient blood flow to the trabecular spaces in order to enable penile erection. Contractility of cavernous arteries is regulated by the peripheral autonomic nervous system and endogenous factor

Upper respiratory tract infections in general practice: Diagnosis, antibiotic prescribing, duration of symptoms and use of diagnostic tests

A diagnosis/antibiotic prescribing study was performed in 5 counties in Sweden for 1 week in November 2000. As part of this study, the characteristics and clinical management of patients with upper respiratory tract infections ( n = 2899) in primary care were analyzed. Almost half of the patients were aged < 15 y and one-fifth of the patients consulted out of hours. Of all patients seeking primary

HCCI Closed-Loop Combustion Control Using Fast Thermal Management

This study applies Closed-Loop Combustion Control (CLCC) using Fast Thermal Management (FTM) on a multi-cylinder Variable Compression Ratio (VCR) engine together with load control, to achieve a favorable combustion phasing and load at all times. Step changes of set points for combustion phasing, Compression Ratio (CR), and load together with ramps of engine speed with either constant load, i.e., l

Laser Diagnostics for Applications to In-Cylinder Engine Investigations

In the work presented in the thesis laser diagnostics was employed primarily in the investigation of engines, but was also used to study soot in flames. Quantitative measurements were performed for visualizing both in-cylinder soot formation and DME sprays in a combustion vessel. The DME sprays inside a diesel truck engine were also qualitatively investigated. The combustion process in the HCCI en

Chronic carrier state in mothers of infants with group B streptococcal infections

Seven of eight women who had given birth to infants with early onset or intrauterine infection caused by group B streptococci remained carriers of the same serotype of group B streptococci up to 38 months after their pregnancy. In contrast, only 34 of 88 group B streptococci carriers who had given birth to healthy infants harbored the same serotype at the 34 months' follow-up (P = .009). Among the

Expression of a selenomethionine derivative and preliminary crystallographic studies of human cystatin C

Human cystatin C, a protein with amyloidogenic properties and a potent inhibitor of papain-like mammalian proteases, has been produced in its full-length form by recombinant techniques and crystallized in two polymorphic forms: cubic and tetragonal. A selenomethionyl derivative of the protein, obtained by Escherichia coli expression and with complete Met→Se-Met substitution confirmed by mass spect

On the optical theory of underwater vision in humans

Defocus changes the visual contrast sensitivity function, thereby creating a complex curve with local dips and peaks. Since underwater vision in humans is severely defocused, we used optical theory and the phenomenon of spurious resolution to predict how well humans can see in this environment. The values obtained correspond well with experimental measurements of underwater human acuity from earli

Sex differences in bone size and bone mineral density exist before puberty. The Copenhagen School Child Intervention Study (CoSCIS)

Background: The aim of this study was to provide normative data of bone mineral density (BMD; g/cm(2)) of the forearm and the calcaneus, evaluated by peripheral dual X ray absorbtiometry (DXA), in children aged 6 to 7 years of age and to evaluate the association with anthropometrics and sex. Materials and methods: 368 boys and 326 girls with a mean age of 6.7 +/- 0.4 years participated. BMD was me

Seed bank in annuals: Competition between banker and non-banker morphs

Seed bank is a plant life history strategy against the unpredictability of the biotic and the abiotic environment. We simulated competition between a seed banking and a non-banking morph of an annual plant. A constant fraction of the banker morph seeds was allocated to the seed bank, where they had a constant mortality and germination rate. All surviving seeds of the non-banker morph germinated in

Regulation of hematopoiesis by the Smad signaling pathway

Popular Abstract in Swedish Varje dag bildas ca 10^12 nya blodceller i människokroppen. Denna enorma produktion av celler utgår från benmärgen och pågår under hela vårt liv. Ytterst sett är denna process beroende av en till antalet liten cellpopulation av sk blodstamceller eller hematopoietiska stamceller. Den enorma potential som vilar i detta system illustreras av det faktum att en enda blodstamHematopoietic stem cells (HSCs) reside in the bone marrow (BM) of adult individuals and are ultimately responsible for the continuous production of blood cells throughout life. The regulation of HSCs in vivo is tightly regulated by both intrinsic and extrinsic factors. The Smad-signaling pathway is an evolutionary conserved signaling circuitry with critical functions during embryogenesis and throu

Climate change and the optimal arrival of migratory birds

Recent climate change has sparked an interest in the timing of biological events, which is a general problem in life-history evolution. Reproduction in many organisms breeding in seasonal environments, e. g. migratory birds, is dependent on the exploitation of a short but rich food supply. If the seasonal timing of the food peak advances owing to climate change, then one would expect the bird to t

Torp och backstugor i Länghem : en studie av bebyggelsens förändringar från 1600-talet till början av 1900-talet.

The paper is based on an inventory of crofts and cottages that was made in the parish of Länghem in the southern part of the province of Västergötland, Sweden at the end of the 1950ies and the beginning of the 1960ies. The parish of Länghem has both manors (the medieval Torpa and Hofsnäs and the 17th century Sällerås) and independent villages. The inventory was made quite traditionally. We tried t

Enhancement of apomorphine-induced penile erection in the rat by a selective alpha(1D)-adrenoceptor antagonist.

Effects of A-322312 (alpha(1B)-adrenoceptor (AR) antagonist), A-119637 (alpha(1D)-AR antagonist), prazosin (non-selective alpha(1)-AR antagonist), and yohimbine (alpha(2)-AR antagonist) were studied in rat corpus cavernosum (CC) and cavernous artery (Acc) preparations. Effects of intracavernous (i.c.) or intraperitoneal (i.p.) administration of alpha(1)-AR antagonists on apomorphine-induced erecti

Seeking evidence that cell kill guided thermotherapy gives results not inferior to those of transurethral prostate resection: Results of a pooled analysis of 3 studies of feedback transurethral microwave thermotherapy

Purpose: We compared ProstaLund Feedback Treatment(R) (PLFT(R)) to transurethral prostate resection (TURP) in terms of efficacy and safety in a pooled analysis of 3 clinical studies with 1-year followup. Materials and Methods: Overall raw data on 183 patients with PLFT(R) and 65 with TURP were pooled. All studies had identical inclusion criteria, and the efficacy and safety of the method were eval

Behind the Charts - Exploring Conditions for High Level Emergency Response Management in a Complex Environment

The thesis uses, as a starting point for a discussion of emergency response management, the problem of gradual coordinated adaptation of management functions in relation to an event and its dynamics. Empirical observations and analyses carried out in the research project show that important problemsolving processes not included in, and sometimes diverging from, planning and preparations frequently

Deposition of particle-attached radon progeny in the respiratory tract - an experimental study of children and adults in home environments

A method to study total deposition of aerosol attached radon progeny in children and adults have been validated and used in home environments. Two persons, one child and one adult are tested simultaneously, thus inhaling from the same aerosol and allowing for a direct comparison. The aim of the study was to increase the knowledge of the lung deposition and thereby the knowledge of the radiation do

Frequency chirp of harmonic and attosecond pulses

We study the phase of the atomic polarization in the process of high-order harmonic generation. Its dependence on the laser intensity and the harmonic order induce a frequency variation in time (chirp) respectively of the harmonic pulses and attosecond pulses. We review the recent experimental results on the temporal characterization of the harmonic emission and show that measurements performed us