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index of activities of daily living

SEE: under index.

index case

The first person whose condition leads to the investigation of a hereditary or infectious disease.

India ink

(in′dē-ă) A black ink, commonly used in the past, made from lampblack. In clinical pathology, it is used to stain fungi, such as Cryptococcus neoformans.

Indian Health Service

ABBR: IHS. A bureau of the U.S. Department of Health and Human Services, responsible for providing public health and medical services to Native Americans.


(ĭn′dĭ-kăn″) 1. Potassium salt of indoxylsulfate, found in sweat and urine, and formed when intestinal bacteria convert tryptophan to indole. 2. In plants, a yellow glycoside, the precursor of the dye indigo.


(ĭn′dĭ-kănt) 1. Something such as a sign or symptom that points to the presence of a disease. 2. Something such as loss of a symptom or sign that indicates that the treatment of the disease is proper and effective.


(in″dĭ-kā′shŏn) [L. indicare, a setting, valuation] 1. A sign or circumstance that suggests the proper treatment of a disease. 2. An approved use for any therapeutic intervention or drug, e.g., in the U.S., a use that has met the standards set by the U.S. Food and Drug Administration. SYN: labeled use.

causal i. An indication provided by the knowledge of the cause of a disease.

symptomatic i. An indication provided by the symptoms of a disease rather than because of precise knowledge of the actual disease process. For example, a patient may be given acetaminophen without knowing the cause of the symptoms of headache or fever


(in″dĭ-kāt′ŏr) [L. indicare, to show] In chemical analysis, a substance that can be used to determine pH. In a more general sense, any substance that can be used to determine the completeness of a chemical reaction, as in volumetric analysis. SEE: table.

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Colors of Indicators of pH
Toward Acid Toward Alkali Range of pH
Methyl yellow Red Yellow 2.9–4.0
Congo red Blue Red 3.0–5.2
Methyl orange Red Yellow 3.1–4.4
Methyl red Red Yellow 4.2–6.2
Litmus Red Blue 4.5–8.3
Bromcresol purple Yellow Purple 5.2–6.8
Bromothymol blue Yellow Blue 6.0–7.6
Phenol red Yellow Red 6.8–8.4
Phenolphthalein Colorless Pink 8.2–10.0

empirical i. An instrument, experimental condition, or clinical procedure that is used for observation, measurement, or protocol writing, esp. in clinical research.

health i. SEE: health indicator.

quality i. Any measure of the process, performance, or outcome of health ...

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