Complicity: Association with or participation in an act that is, or is perceived to be, criminal or immoral. One is complicitous when one promotes or unduly benefits from practices or institutions that are morally or legally suspect.Directed Tissue Donation: Tissue, organ, or gamete donation intended for a designated recipient.Fetal Tissue Transplantation: Transference of fetal tissue between individuals of the same species or between individuals of different species.Life: The state that distinguishes organisms from inorganic matter, manifested by growth, metabolism, reproduction, and adaptation. It includes the course of existence, the sum of experiences, the mode of existing, or the fact of being. Over the centuries inquiries into the nature of life have crossed the boundaries from philosophy to biology, forensic medicine, anthropology, etc., in creative as well as scientific literature. (Random House Unabridged Dictionary, 2d ed; Dr. James H. Cassedy, NLM History of Medicine Division)Personhood: The state or condition of being a human individual accorded moral and/or legal rights. Criteria to be used to determine this status are subject to debate, and range from the requirement of simply being a human organism to such requirements as that the individual be self-aware and capable of rational thought and moral agency.Beginning of Human Life: The point at which religious ensoulment or PERSONHOOD is considered to begin.Tissue Transplantation: Transference of tissue within an individual, between individuals of the same species, or between individuals of different species.Aborted Fetus: A mammalian fetus expelled by INDUCED ABORTION or SPONTANEOUS ABORTION.Pregnant Women: Human females who are pregnant, as cultural, psychological, or sociological entities.Brain Tissue Transplantation: Transference of brain tissue, either from a fetus or from a born individual, between individuals of the same species or between individuals of different species.Tissue and Organ Procurement: The administrative procedures involved with acquiring TISSUES or organs for TRANSPLANTATION through various programs, systems, or organizations. These procedures include obtaining consent from TISSUE DONORS and arranging for transportation of donated tissues and organs, after TISSUE HARVESTING, to HOSPITALS for processing and transplantation.Hospitals, State: Hospitals controlled by agencies and departments of the state government.Organ Transplantation: Transference of an organ between individuals of the same species or between individuals of different species.Liver Transplantation: The transference of a part of or an entire liver from one human or animal to another.Hand Transplantation: The transference of a complete HAND, as a composite of many tissue types, from one individual to another.Transplantation, Heterotopic: Transplantation of tissue typical of one area to a different recipient site. The tissue may be autologous, heterologous, or homologous.Transplantation, Homologous: Transplantation between individuals of the same species. Usually refers to genetically disparate individuals in contradistinction to isogeneic transplantation for genetically identical individuals.Transplantation: Transference of a tissue or organ from either an alive or deceased donor, within an individual, between individuals of the same species, or between individuals of different species.Fetus: The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.Tissue Donors: Individuals supplying living tissue, organs, cells, blood or blood components for transfer or transplantation to histocompatible recipients.Transplantation Immunology: A general term for the complex phenomena involved in allo- and xenograft rejection by a host and graft vs host reaction. Although the reactions involved in transplantation immunology are primarily thymus-dependent phenomena of cellular immunity, humoral factors also play a part in late rejection.Kidney Transplantation: The transference of a kidney from one human or animal to another.Ethics, Medical: The principles of professional conduct concerning the rights and duties of the physician, relations with patients and fellow practitioners, as well as actions of the physician in patient care and interpersonal relations with patient families.Graft Survival: The survival of a graft in a host, the factors responsible for the survival and the changes occurring within the graft during growth in the host.Bone Marrow Transplantation: The transference of BONE MARROW from one human or animal to another for a variety of purposes including HEMATOPOIETIC STEM CELL TRANSPLANTATION or MESENCHYMAL STEM CELL TRANSPLANTATION.Primary Ovarian Insufficiency: Cessation of ovarian function after MENARCHE but before the age of 40, without or with OVARIAN FOLLICLE depletion. It is characterized by the presence of OLIGOMENORRHEA or AMENORRHEA, elevated GONADOTROPINS, and low ESTRADIOL levels. It is a state of female HYPERGONADOTROPIC HYPOGONADISM. Etiologies include genetic defects, autoimmune processes, chemotherapy, radiation, and infections.Skin Transplantation: The grafting of skin in humans or animals from one site to another to replace a lost portion of the body surface skin.Hematopoietic Stem Cell Transplantation: Transfer of HEMATOPOIETIC STEM CELLS from BONE MARROW or BLOOD between individuals within the same species (TRANSPLANTATION, HOMOLOGOUS) or transfer within the same individual (TRANSPLANTATION, AUTOLOGOUS). Hematopoietic stem cell transplantation has been used as an alternative to BONE MARROW TRANSPLANTATION in the treatment of a variety of neoplasms.Cryopreservation: Preservation of cells, tissues, organs, or embryos by freezing. In histological preparations, cryopreservation or cryofixation is used to maintain the existing form, structure, and chemical composition of all the constituent elements of the specimens.Heart Transplantation: The transference of a heart from one human or animal to another.Transplantation, Autologous: Transplantation of an individual's own tissue from one site to another site.Lung Transplantation: The transference of either one or both of the lungs from one human or animal to another.Stem Cell Transplantation: The transfer of STEM CELLS from one individual to another within the same species (TRANSPLANTATION, HOMOLOGOUS) or between species (XENOTRANSPLANTATION), or transfer within the same individual (TRANSPLANTATION, AUTOLOGOUS). The source and location of the stem cells determines their potency or pluripotency to differentiate into various cell types.Transplantation Conditioning: Preparative treatment of transplant recipient with various conditioning regimens including radiation, immune sera, chemotherapy, and/or immunosuppressive agents, prior to transplantation. Transplantation conditioning is very common before bone marrow transplantation.Maternal-Fetal Exchange: Exchange of substances between the maternal blood and the fetal blood at the PLACENTA via PLACENTAL CIRCULATION. The placental barrier excludes microbial or viral transmission.Placenta: A highly vascularized mammalian fetal-maternal organ and major site of transport of oxygen, nutrients, and fetal waste products. It includes a fetal portion (CHORIONIC VILLI) derived from TROPHOBLASTS and a maternal portion (DECIDUA) derived from the uterine ENDOMETRIUM. The placenta produces an array of steroid, protein and peptide hormones (PLACENTAL HORMONES).Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Ovary: The reproductive organ (GONADS) in female animals. In vertebrates, the ovary contains two functional parts: the OVARIAN FOLLICLE for the production of female germ cells (OOGENESIS); and the endocrine cells (GRANULOSA CELLS; THECA CELLS; and LUTEAL CELLS) for the production of ESTROGENS and PROGESTERONE.Graft Rejection: An immune response with both cellular and humoral components, directed against an allogeneic transplant, whose tissue antigens are not compatible with those of the recipient.Pancreas Transplantation: The transference of a pancreas from one human or animal to another.Islets of Langerhans Transplantation: The transference of pancreatic islets within an individual, between individuals of the same species, or between individuals of different species.Abortion, Veterinary: Premature expulsion of the FETUS in animals.Cell Transplantation: Transference of cells within an individual, between individuals of the same species, or between individuals of different species.Transplantation Chimera: An organism that, as a result of transplantation of donor tissue or cells, consists of two or more cell lines descended from at least two zygotes. This state may result in the induction of donor-specific TRANSPLANTATION TOLERANCE.Immunosuppressive Agents: Agents that suppress immune function by one of several mechanisms of action. Classical cytotoxic immunosuppressants act by inhibiting DNA synthesis. Others may act through activation of T-CELLS or by inhibiting the activation of HELPER CELLS. While immunosuppression has been brought about in the past primarily to prevent rejection of transplanted organs, new applications involving mediation of the effects of INTERLEUKINS and other CYTOKINES are emerging.Graft vs Host Disease: The clinical entity characterized by anorexia, diarrhea, loss of hair, leukopenia, thrombocytopenia, growth retardation, and eventual death brought about by the GRAFT VS HOST REACTION.Transplantation, Isogeneic: Transplantation between genetically identical individuals, i.e., members of the same species with identical histocompatibility antigens, such as monozygotic twins, members of the same inbred strain, or members of a hybrid population produced by crossing certain inbred strains.Living Donors: Non-cadaveric providers of organs for transplant to related or non-related recipients.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Cord Blood Stem Cell Transplantation: Transplantation of STEM CELLS collected from the fetal blood remaining in the UMBILICAL CORD and the PLACENTA after delivery. Included are the HEMATOPOIETIC STEM CELLS.Heart-Lung Transplantation: The simultaneous, or near simultaneous, transference of heart and lungs from one human or animal to another.Gestational Age: The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated as the time from the last day of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization.Fetal Research: Experimentation on, or using the organs or tissues from, a human or other mammalian conceptus in the postembryonic period, after the major structures have been outlined. In humans, this corresponds to the period from the third month after fertilization until birth.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Transplantation Tolerance: An induced state of non-reactivity to grafted tissue from a donor organism that would ordinarily trigger a cell-mediated or humoral immune response.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.