SpermatogenesisSpermatocytesTestisSpermatidsSertoli CellsSeminiferous TubulesSpermatogoniaSpermatozoaSeminiferous EpitheliumMeiosisInfertility, MalePachytene StageSperm CountBlood-Testis BarrierGerm CellsFertilityMeiotic Prophase IOligospermiaLeydig CellsAzoospermiaTestosteroneContraceptive Agents, MaleEpididymisSynaptonemal ComplexCryptorchidismProphaseOrgan SizeChromosome PairingY ChromosomeSexual MaturationSperm MotilitySex ChromosomesGene Expression Regulation, DevelopmentalMolecular Sequence DataFollicle Stimulating HormoneTesticular DiseasesRNA, MessengerAcrosomeAntispermatogenic AgentsImmunohistochemistrySperm TailChromosomesIn Situ HybridizationSpermatogenesis-Blocking AgentsSperm MaturationChromosomes, Human, YSeminal VesiclesSperm HeadProtaminesBase SequenceCyclin A1GametogenesisHaploidyAmino Acid SequenceNuclear ProteinsMice, KnockoutDipteraOogenesisRats, Sprague-DawleyMice, Inbred C57BLMetaphaseGene ExpressionDrosophila ProteinsSalamandridaeInhibinsReverse Transcriptase Polymerase Chain ReactionSex ChromatinDrosophila melanogasterGonadotropinsGenitalia, MaleHistonesCell NucleusAndrogen-Binding ProteinOrgan SpecificityMicroscopy, ElectronIn Situ Nick-End LabelingAcrosinRNA-Binding ProteinsLuteinizing HormoneSertoli Cell-Only SyndromeApoptosisX ChromosomeVaricoceleCell DifferentiationBlotting, NorthernSemenMice, Mutant StrainsSeminal Plasma ProteinsTriethylenemelamineMice, TransgenicMutationDNA, ComplementaryGene Expression RegulationDrosophilaDNA-Binding ProteinsProteinsBlotting, WesternAndrogensOrthopteraCloning, Molecular