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Estrogens and phytoestrogens in male infertility.

PURPOSE OF REVIEW: A time-related negative trend in male reproductive function has been suggested. It has been hypothesized that this is due to exposure to chemicals interfering with the action of sex hormones. Also a negative effect of phytoestrogens on male fertility has been postulated. This review aimed to review the epidemiological evidence of deteriorating male reproductive function and summ

SmartHand tactile display: A new concept for providing sensory feedback in hand prostheses.

Abstract A major drawback with myoelectric prostheses is that they do not provide the user with sensory feedback. Using a new principle for sensory feedback, we did a series of experiments involving 11 healthy subjects. The skin on the volar aspect of the forearm was used as the target area for sensory input. Experiments included discrimination of site of stimuli and pressure levels at a single st

CCAAT/enhancer binding protein alpha (C/EBP alpha)-induced transdifferentiation of pre-B cells into macrophages involves no overt retrodifferentiation

Earlier work has shown that pre-B cells can be converted into macrophages by the transcription factor CCAAT/enhancer binding protein a at very high frequencies. Using this system, we performed a systematic analysis of whether during transdifferentiation the cells transiently reactivate progenitor-restricted genes or even retrodifferentiate. A transcriptome analysis of transdifferentiating cells sh

Source apportionment of the carbonaceous aerosol in Norway - quantitative estimates based on C-14, thermal-optical and organic tracer analysis

In the present study, source apportionment of the ambient summer and winter time particulate carbonaceous matter (PCM) in aerosol particles (PM1 and PM10) has been conducted for the Norwegian urban and rural background environment. Statistical treatment of data from thermal-optical, C-14 and organic tracer analysis using Latin Hypercube Sampling has allowed for quantitative estimates of seven diff

Unveiling systematic biases in the 1D LTE excitation-ionization balance of Fe for FGK stars: a novel approach to determination of stellar parameters

We present a comprehensive analysis of different techniques available for the spectroscopic analysis of FGK stars and provide a recommended methodology which efficiently estimates accurate stellar atmospheric parameters for large samples of stars. Our analysis includes a simultaneous equivalent width analysis of Fe I and Fe II spectral lines, and for the first time, utilizes on-the-fly non-local t

Physiological mechanisms mediating costs of immune responses: what can we learn from studies of birds?

Activating the immune system has associated fitness costs, both immediate costs in the form of reduced current reproduction and long-term costs in the form of reduced life span and future reproduction. This indicates that immune system activation can be an important agent in life history trade-offs. In this review, we evaluate the importance of four currencies generally considered as potential med

Changes in amorphous silica sequestration with eutrophication of riverine impoundments

The effect of eutrophication on particulate amorphous silica (ASi) sequestration was isolated and quantified in Lake St. Croix and Lake Pepin, two natural, human-impacted impoundments of the upper Mississippi River. In contrast to impoundments behind engineered dams, where silica (Si) fluxes may be changed by various aspects of dam construction, these two riverine lakes have long (9,000+ years) se

Visibility of single spiculations in digital breast tomosynthesis

Purpose: To investigate the visibility of single spiculations in digital breast tomosynthesis (DBT). Method: Simulated spheres (6 mm diameter) with single spiculations were added to projection images acquired on a DBT system (MAMMOMAT Inspiration, Siemens). The spiculations had a cylindrical shape and were randomly, diagonally aligned (at four different positions: +/- pi/4 or +/- 3 pi/4) at a plan

Third world list of cetrarioid lichens: A databased tool for documentation of nomenclatural data - lessons learned

The third version of the world list of cetrarioid lichens contains 572 names representing 149 accepted species. It is presented in a new, electronical form, based on a FileMaker-powered database, allowing users to view data in different sets and to perform searches. Type information is added for most of the names, and new information regarding the phylogenetic status of accepted taxa is introduced

Structural Basis for Adenosylcobalamin Activation in AdoCbl-Dependent Ribonucleotide Reductases

Class II ribonucleotide reductases (RNR) catalyze the formation of an essential thiyl radical by homolytic cleavage of the Co-C bond in their adenosylcobalamin (AdoCbl) cofactor. Several mechanisms for the dramatic acceleration of Co-C bond cleavage in AdoCbl-dependent enzymes have been advanced, but no consensus yet exists. We present the structure of the class II RNR from Thermo toga maritima in

Environmental exposure to POPs and heavy metals in urban children from Dhaka, Bangladesh

Persistent organic pollutants (POPs) and heavy metals are well known environmental pollutants. Even though numerous studies have been carried out to assess human exposures to these compounds, there is still a lack of data on humans from developing countries, especially in underprivileged children. The objective of this study was to assess the exposure to POPs and heavy metals in children from Dhak

Women pioneers in basal ganglia surgery

Background: Stereotactic functional neurosurgery on basal ganglia has a long history and the pioneers are mostly men. We aimed at finding out if there were women who have contributed pioneering work in this field. Methods: The literature was searched to identify women who have been first to publish innovative papers related to human basal ganglia surgery. Results: Six women fulfilling our criteria

Twilight ascents by common swifts, Apus apus, at dawn and dusk: acquisition of orientation cues?

Common swifts are specialist flyers spending most of their life aloft, including night-time periods when this species roosts on the wing. Nocturnal roosting is preceded by a vertical ascent in twilight conditions towards altitudes of up to 2.5 km, behaviour previously explained as flight altitude selection for sleeping. We examined the nocturnal flight behaviour of swifts, as uniquely identified b

beta-Cell Specific Overexpression of GPR39 Protects against Streptozotocin-Induced Hyperglycemia

Mice deficient in the zinc-sensor GPR39, which has been demonstrated to protect cells against endoplasmatic stress and cell death in vitro, display moderate glucose intolerance and impaired glucose-induced insulin secretion. Here, we use the Tet-On system under the control of the proinsulin promoter to selectively overexpress GPR39 in the beta cells in a double transgenic mouse strain and challeng

2-cm versus 4-cm surgical excision margins for primary cutaneous melanoma thicker than 2 mm: a randomised, multicentre trial

Background Optimum surgical resection margins for patients with clinical stage IIA-C cutaneous melanoma thicker than 2 mm are controversial. The aim of the study was to test whether survival was different for a wide local excision margin of 2 cm compared with a 4-cm excision margin. Methods We undertook a randomised controlled trial in nine European centres. Patients with cutaneous melanoma thicke

Functional Mannose-Binding Lectin Haplotype Variants are Associated with Alzheimer's Disease

Mannan-Binding lectin (MBL) is a serum lectin and an important constituent of the innate immune system. Processes linked to the innate immune response have previously been implicated in Alzheimer's disease (AD). MBL is associated with blood vessels in the brain and AD patients demonstrate lower MBL levels in the cerebrospinal fluid compared to controls. We investigated six single nucleotide polymo