Category: S

The wall of the embryonic gut, which consists of a layer of endoderm with a layer of mesoderm outside it. The yolk sac is a continuation of this structure.  

The part of the skull that is derived from the pharyngeal arches, i.e. the mandible (lower jaw).  

A device for showing the heart beat or pulse as a visible signal, especially as a continuous wave signal on a cathode-ray tube. An apparatus that visually displays the pulsations of an artery.  

A device to record the heart beat or pulse in the form of amplified sound waves played through a loudspeaker or earphones. A device for making pulse vibrations audible.  

Any instrument for measuring the intensity and wavelengths of visible or invisible electromagnetic radiations. A spectroscope so constructed that angular deviation of a ray of light produced by a prism or by a diffraction grating thus indicates the wavelength. An apparatus that separates radiation into its constituent wavelengths. An apparatus for gauging the deflection of…

An instrument (a spectrometer or spectroscope) that produces a photographic record (spectrogram) of the intensity and wavelength of electromagnetic radiations. An instrument designed to photograph spectra on a sensitive photographical plate. A spectrometer that offers a lasting photographic documentation of a radiation spectrum. A spectroscopic device designed for capturing a spectrum through photography.  

Hospitals for the care of mentally ill patients who are also dangerous and must therefore by kept securely.  

The larvae of certain tapeworms, including species of Diphyllobothrium and Spirometra, which may accidentally infect man. They are actually plerocercoids, but the generic name Sparganum is given to them since they fail to develop into adults and definite classification of the species is not possible from the larvae alone.  

Fine-caliber tubes for insertion into subcutaneous tissue to drain excess fluid. They are rarely used in practice today. A very small tube pushed into tissue to help drain edema fluid. It is used in severe congestive heart failure to relieve edema of the legs. Tiny metal tubes designed for placement into tissues to remove excess…

The body wall of the early embryo, which consists of a simple layer of ectoderm lined with mesoderm. The amnion is a continuation of this structure outside the embryo.