نتایج جستجو برای: sperm density

تعداد نتایج: 446003  

2012
Jan Beran Luděk Stádník Jiří Bezdíček František Louda Jaroslav Čítek Jaromír Ducháček

The objectives were to evaluate the effects of sire and content of fresh or ionised egg yolk in extenders on sperm motility and share of live and dead sperm in collected ejaculate, in thawed artificial insemination (AI) doses, and during thermodynamic testing compared to extenders not containing egg yolk. Ejaculates were collected once a week from 4 Holstein bulls. Each of the 20 ejaculate samp...

B Saranjam, D Panahi, M Kaydani, M.B Abdollahi,

Background & objectives: Cell phone microwave (MW) is one of the most harmful physical agents in modern society. This study was designed to determine the effects of exposure to cell phone microwaves on mice sperm morphologic indices. Methods: Animals were divided into two groups including: Microwave (MW) (n=6; exposed to 950-MHz cell phone MW with 5 W output power density and 200 KHz modulatio...

2016
Hyacinth N. Highland A. Sharma Rishika S. Shaikh Almira P. Bansal Kanthi

BACKGROUND Infertility being a burning issue, the male itself contributes about 40% as a cause, as evident by statistical data. However, Assisted Reproductive Technology (ART) has emerged as a powerful tool in the management of infertility. Sperm preparation techniques govern the selection procedure to separate functional spermatozoa which can then be used in IUI, IVF, and ART and for cryoprese...

Journal: :international journal of fertility and sterility 0
mohammad hossein nasr esfahani mohammad reza deemeh marziyeh tavalaee mohammad hadi sekhavati hamid gourabi

objective: selection of sperm for intra-cytoplasmic sperm injection (icsi) is usually considered as the ultimate technique to alleviate male-factor infertility. in routine icsi, selection is based on morphology and viability which does not necessarily preclude the chance injection of dna-damaged or apoptotic sperm into the oocyte. sperm with high negative surface electrical charge, named “zeta ...

Journal: :Mutagenesis 2000
E T Donnelly N McClure S E Lewis

Sperm DNA integrity is of paramount importance for the accurate conveyance of genetic material. DNA damage may be a major contributory factor in male infertility as DNA from sperm of infertile men has been found to be more susceptible to induced DNA damage in vitro than DNA from fertile men. Reactive oxygen species (ROS) are a significant source of DNA damage and human sperm are extremely sensi...

2010
Hiltrud Merzenich Hajo Zeeb Maria Blettner

BACKGROUND Carlsen and coworkers (1992) reviewed 61 heterogeneous observational studies on semen quality published between 1938 and 1990. This review indicates that mean sperm density decreased significantly between 1940 and 1990. An extended meta-analysis with 101 studies confirmed a decline in sperm density for the period from 1934 to 1996 (2000). The key message of the meta-analyses is that ...

2015
Seyed Vahab Shojaedini Masoud Heydari

ARTICLE HISTORY: Received 15 March 2014 Revised 30 May 2014 Accepted 22 June 2014 In this paper, a new method is introduced for sperm detection in microscopic images for infertility treatment. In this method, firstly a hypothesis testing function is defined to separate sperms from plasma, non-sperm semen particles and noise. Then, some primary candidates are selected for sperms by watershed-bas...

Journal: :Biology of reproduction 2006
Tamer Said Ashok Agarwal Sonja Grunewald Manja Rasch Thomas Baumann Christian Kriegel Liang Li Hans-Juergen Glander Anthony J Thomas Uwe Paasch

Magnetic cell sorting (MACS) using annexin V-conjugated microbeads eliminates apoptotic spermatozoa based on the externalization of phosphatidylserine residues. The procedure delivers two sperm fractions: annexin V-negative (nonapoptotic) and annexin V-positive (apoptotic). Our aim was to determine whether the sperm fertilizing potential can be improved by selecting a nonapoptotic fraction usin...

Journal: :Evolution; international journal of organic evolution 2011
Kenneth M Fedorka Wade E Winterhalter Brian Ware

Sperm competition is a potent postcopulatory selective force where sperm from rival males compete to fertilize a limited set of ova. Considering that sperm production is costly, we expect males to strategically allocate sperm in accordance with the level of competition. Accordingly, previous work has examined a male's strategic allocation in terms of sperm number. However, the seminal fluid pro...

Journal: :Human reproduction 2010
Luke Simon Gunnar Brunborg Michael Stevenson Deborah Lutton Joanne McManus Sheena E M Lewis

BACKGROUND Sperm DNA damage shows great promise as a biomarker of infertility. The study aim is to determine the usefulness of DNA fragmentation (DF), including modified bases (MB), to predict assisted reproduction treatment (ART) outcomes. METHODS DF in 360 couples (230 IVF and 130 ICSI) was measured by the alkaline Comet assay in semen and in sperm following density gradient centrifugation ...

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