Related Experiment Video

Updated: Aug 16, 2026

Modeling Posthemorrhagic Hydrocephalus of Prematurity in Rats
04:12

Modeling Posthemorrhagic Hydrocephalus of Prematurity in Rats

Published on: March 28, 2025

Is there a seasonal variation in the diagnosis of oligohydramnios?

Michael W Varner1, William D Noble, Mitchell Dombrowski

  • 1Department of Obstetrics and Gynecology, University of Utah, Salt Lake City 84132, USA. mvarner@hsc.utah.edu

The Journal of Maternal-Fetal & Neonatal Medicine : the Official Journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians
|September 13, 2005
PubMed
Abstract

Related Concept Videos

Diabetes Insipidus II: Pathophysiology01:22

Diabetes Insipidus II: Pathophysiology

Normally, water balance is maintained through three interconnected mechanisms: the hypothalamic thirst center, the synthesis and release of antidiuretic hormone (ADH, or vasopressin), and the kidneys' responsiveness to this hormone. ADH is synthesized in the hypothalamus, released from the posterior pituitary, and acts on the distal nephron, allowing water reabsorption and concentrated urine production.Diabetes Insipidus and Its TypesIn diabetes insipidus (DI), this regulatory system is...
Ovarian Cycle01:27

Ovarian Cycle

The menstrual cycle includes a critical component known as the ovarian cycle, which undergoes two main phases each month—the follicular phase and the luteal phase. The follicular phase is variable and averaging around 14 days. Ovulation, triggered by a surge in luteinizing hormone (LH), marks the transition between the two phases. The second phase, the luteal phase, is relatively consistent, lasting approximately 14 days, and is marked by the activity of the corpus luteum. While a cycle length...
Diabetes Insipidus I: Introduction01:29

Diabetes Insipidus I: Introduction

Definition Diabetes insipidus is a disorder marked by the production of large amounts of dilute urine because of impaired vasopressin production, release, or kidney response. The lack of effective vasopressin action limits water reabsorption in the renal collecting ducts, which leads to excessive urinary water loss and intense thirst.Clinical PresentationIndividuals with diabetes insipidus report persistent thirst and very high urine output. In severe cases, fluid intake can reach up to 20...
Oogenesis02:07

Oogenesis

In human women, oogenesis produces one mature egg cell or ovum for every precursor cell that enters meiosis. This process differs in two unique ways from the equivalent procedure of spermatogenesis in males. First, meiotic divisions during oogenesis are asymmetric, meaning that a large oocyte (containing most of the cytoplasm) and minor polar body are produced as a result of meiosis I, and again following meiosis II. Since only oocytes will go on to form embryos if fertilized, this unequal...
Hyperosmolar Hyperglycemic State01:21

Hyperosmolar Hyperglycemic State

Hyperosmolar Hyperglycemic State, or HHS, is a serious and life-threatening complication of type 2 diabetes mellitus. It is characterized by three main features: severe hyperglycemia, profound dehydration, and elevated serum osmolality, all occurring without significant ketoacidosis.HHS typically develops in older adults or individuals with limited access to fluids. This may result from illness, cognitive impairment, or medications such as diuretics or corticosteroids. These factors reduce...
Renal Tubule and Collecting Duct01:24

Renal Tubule and Collecting Duct

The renal tubule is divided into three parts: the proximal convoluted tubule (PCT), the Loop of Henle (LOH), and the distal convoluted tubule (DCT).
Proximal Convoluted Tubule (PCT):
The PCT is the initial segment of the renal tubule, extending from the Bowman's capsule that encloses the glomerulus. Its convoluted structure and microvilli-lined cells increase the surface area for reabsorption. The PCT reabsorbs glucose, amino acids, sodium, and water from the filtrate, ensuring essential...