Hydronephrosis: Abnormal enlargement or swelling of a KIDNEY due to dilation of the KIDNEY CALICES and the KIDNEY PELVIS. It is often associated with obstruction of the URETER or chronic kidney diseases that prevents normal drainage of urine into the URINARY BLADDER.Ureteral Obstruction: Blockage in any part of the URETER causing obstruction of urine flow from the kidney to the URINARY BLADDER. The obstruction may be congenital, acquired, unilateral, bilateral, complete, partial, acute, or chronic. Depending on the degree and duration of the obstruction, clinical features vary greatly such as HYDRONEPHROSIS and obstructive nephropathy.Kidney Pelvis: The flattened, funnel-shaped expansion connecting the URETER to the KIDNEY CALICES.Urethral Obstruction: Partial or complete blockage in any part of the URETHRA that can lead to difficulty or inability to empty the URINARY BLADDER. It is characterized by an enlarged, often damaged, bladder with frequent urges to void.Urography: Radiography of any part of the urinary tract.Ureteral Diseases: Pathological processes involving the URETERS.Ureter: One of a pair of thick-walled tubes that transports urine from the KIDNEY PELVIS to the URINARY BLADDER.Vesico-Ureteral Reflux: Retrograde flow of urine from the URINARY BLADDER into the URETER. This is often due to incompetence of the vesicoureteral valve leading to ascending bacterial infection into the KIDNEY.Radioisotope Renography: Graphic tracing over a time period of radioactivity measured externally over the kidneys following intravenous injection of a radionuclide which is taken up and excreted by the kidneys.Urinary Tract: The duct which coveys URINE from the pelvis of the KIDNEY through the URETERS, BLADDER, and URETHRA.Technetium Tc 99m Mertiatide: A technetium diagnostic aid used in renal function determination.Fetal Diseases: Pathophysiological conditions of the FETUS in the UTERUS. Some fetal diseases may be treated with FETAL THERAPIES.Flank Pain: Pain emanating from below the RIBS and above the ILIUM.Retroperitoneal Fibrosis: A slowly progressive condition of unknown etiology, characterized by deposition of fibrous tissue in the retroperitoneal space compressing the ureters, great vessels, bile duct, and other structures. When associated with abdominal aortic aneurysm, it may be called chronic periaortitis or inflammatory perianeurysmal fibrosis.Urolithiasis: Formation of stones in any part of the URINARY TRACT, usually in the KIDNEY; URINARY BLADDER; or the URETER.Kidney Calices: Recesses of the kidney pelvis which divides into two wide, cup-shaped major renal calices, with each major calix subdivided into 7 to 14 minor calices. Urine empties into a minor calix from collecting tubules, then passes through the major calix, renal pelvis, and ureter to enter the urinary bladder. (From Moore, Clinically Oriented Anatomy, 3d ed, p211)Ureteral Neoplasms: Cancer or tumors of the URETER which may cause obstruction leading to hydroureter, HYDRONEPHROSIS, and PYELONEPHRITIS. HEMATURIA is a common symptom.Urologic Surgical Procedures: Surgery performed on the urinary tract or its parts in the male or female. For surgery of the male genitalia, UROLOGIC SURGICAL PROCEDURES, MALE is available.Ureteral Calculi: Stones in the URETER that are formed in the KIDNEY. They are rarely more than 5 mm in diameter for larger renal stones cannot enter ureters. They are often lodged at the ureteral narrowing and can cause excruciating renal colic.Diagnostic Techniques, Urological: Methods and procedures for the diagnosis of diseases or dysfunction of the urinary tract or its organs or demonstration of its physiological processes.Ultrasonography, Prenatal: The visualization of tissues during pregnancy through recording of the echoes of ultrasonic waves directed into the body. The procedure may be applied with reference to the mother or the fetus and with reference to organs or the detection of maternal or fetal disease.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Urologic Diseases: Pathological processes of the URINARY TRACT in both males and females.Polyuria: Urination of a large volume of urine with an increase in urinary frequency, commonly seen in diabetes (DIABETES MELLITUS; DIABETES INSIPIDUS).Dilatation, Pathologic: The condition of an anatomical structure's being dilated beyond normal dimensions.Cystotomy: Surgical incision or puncture into a URINARY BLADDER. Cystotomy may be used to remove URINARY CALCULI, or to perform tissue repair and reconstruction.Pessaries: Devices worn in the vagina to provide support to displaced uterus or rectum. Pessaries are used in conditions such as UTERINE PROLAPSE; CYSTOCELE; or RECTOCELE.Meningism: A condition characterized by neck stiffness, headache, and other symptoms suggestive of meningeal irritation, but without actual inflammation of the meninges (MENINGITIS). Spinal fluid pressure may be elevated but spinal fluid is normal. (DeJong, The Neurologic Examination, 4th ed, p673)Urogenital Abnormalities: Congenital structural abnormalities of the UROGENITAL SYSTEM in either the male or the female.Dysuria: Painful URINATION. It is often associated with infections of the lower URINARY TRACT.Urology: A surgical specialty concerned with the study, diagnosis, and treatment of diseases of the urinary tract in both sexes, and the genital tract in the male. Common urological problems include urinary obstruction, URINARY INCONTINENCE, infections, and UROGENITAL NEOPLASMS.Antibiotic Prophylaxis: Use of antibiotics before, during, or after a diagnostic, therapeutic, or surgical procedure to prevent infectious complications.Urinary Tract Infections: Inflammatory responses of the epithelium of the URINARY TRACT to microbial invasions. They are often bacterial infections with associated BACTERIURIA and PYURIA.Prenatal Diagnosis: Determination of the nature of a pathological condition or disease in the postimplantation EMBRYO; FETUS; or pregnant female before birth.Sex Reassignment Surgery: Surgical treatments used to change the physiological sexual characteristics of an individual.Transsexualism: Severe gender dysphoria, coupled with a persistent desire for the physical characteristics and social roles that connote the opposite biological sex. (APA, DSM-IV, 1994)Andrology: A scientific or medical discipline concerning the study of male reproductive biology, diseases of the male genital organs, and male infertility. Major areas of interest include ENDOCRINOLOGY; SPERMATOGENESIS; semen analysis; FERTILIZATION; CONTRACEPTION; and CRYOPRESERVATION.Access to Information: Individual's rights to obtain and use information collected or generated by others.Urologic Neoplasms: Tumors or cancer of the URINARY TRACT in either the male or the female.Peristalsis: A movement, caused by sequential muscle contraction, that pushes the contents of the intestines or other tubular organs in one direction.Cell Adhesion Molecules: Surface ligands, usually glycoproteins, that mediate cell-to-cell adhesion. Their functions include the assembly and interconnection of various vertebrate systems, as well as maintenance of tissue integration, wound healing, morphogenic movements, cellular migrations, and metastasis.Coxsackie and Adenovirus Receptor-Like Membrane Protein: An Ig superfamily transmembrane protein that localizes to junctional complexes that occur between ENDOTHELIAL CELLS and EPTHELIAL CELLS. The protein may play a role in cell-cell adhesion and is the primary site for the attachment of ADENOVIRUSES during infection.Connexin 43: A 43-kDa peptide which is a member of the connexin family of gap junction proteins. Connexin 43 is a product of a gene in the alpha class of connexin genes (the alpha-1 gene). It was first isolated from mammalian heart, but is widespread in the body including the brain.Muscle, Smooth: Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)Intrauterine Devices: Contraceptive devices placed high in the uterine fundus.Menstruation Disturbances: Variations of menstruation which may be indicative of disease.Intrauterine Devices, Copper: Intrauterine contraceptive devices that depend on the release of metallic copper.Syncope, Vasovagal: Loss of consciousness due to a reduction in blood pressure that is associated with an increase in vagal tone and peripheral vasodilation.Intrauterine Device Expulsion: Spontaneous loss of INTRAUTERINE DEVICES from the UTERUS.Tilt-Table Test: A standard and widely accepted diagnostic test used to identify patients who have a vasodepressive and/or cardioinhibitory response as a cause of syncope. (From Braunwald, Heart Disease, 7th ed)Osteopathic Medicine: A medical discipline that is based on the philosophy that all body systems are interrelated and dependent upon one another for good health. This philosophy, developed in 1874 by Dr. Andrew Taylor Still, recognizes the concept of "wellness" and the importance of treating illness within the context of the whole body. Special attention is placed on the MUSCULOSKELETAL SYSTEM.Osteopathic Physicians: Licensed physicians trained in OSTEOPATHIC MEDICINE. An osteopathic physician, also known as D.O. (Doctor of Osteopathy), is able to perform surgery and prescribe medications.Specialty Boards: Organizations which certify physicians and dentists as specialists in various fields of medical and dental practice.Accreditation: Certification as complying with a standard set by non-governmental organizations, applied for by institutions, programs, and facilities on a voluntary basis.Licensure, Medical: The granting of a license to practice medicine.Education, Medical, Graduate: Educational programs for medical graduates entering a specialty. They include formal specialty training as well as academic work in the clinical and basic medical sciences, and may lead to board certification or an advanced medical degree.