Leukocytes Essays - Biology, Medicine, Anatomy, Cell Biology

Leukocytes Leukocytes and the leukocyte differential count To consider the leukocytes together as a group is something of a granfalloon, because each type of leukocyte has its own function and ontogeny semi-independent of the others. To measure the total leukocyte count and allow this term to mean anything to the doctor is a travesty, yet the wbc count has traditionally been considered a cardinal measurement in a routine laboratory workup for just about any condition. I cannot emphasize too much that to evaluate critically the hematologic status of a patient, one must consider the individual absolute counts of each of the leukocyte types rather than the total wbc count. For such a critical evaluation, the first step is to order a wbc count with differential. In many labs, the result will be reported as a relative differential, something like this: WBC 6000/?L segmented neutrophils 60% band neutrophils 2% lymphocytes 25% monocytes 8% eosinophils 3% basophils 2% Your first task is to multiply the wbc count by each of the percentages given for the cell types; this gives you an absolute differential. Now you're in business to get some idea as to the pathophysiologic status of the patient's blood and marrow. Thus, the illustration above becomes: WBC 6000/?L segmented neutrophils 3600/?L band neutrophils 120/?L lymphocytes 1500/?L monocytes 480/?L eosinophils 180/?L basophils 120/?L The total wbc count is invariably done using an automated method. Routinely, the differential count is done by hand (i.e., through the microscope) in smaller labs, and by automated methods in larger facilities. The automated methods are amazingly accurate, considering the fine distinctions that must often be made in discerning one type of leukocyte from the other. One manufacturer's machine can quite reliably pick out one leukemic blast cell in eight hundred or more leukocytes. Now we shall consider each of the leukocyte types individually. A. Neutrophils The most populous of the circulating white cells, they are also the most short lived in circulation. After production and release by the marrow, they only circulate for about eight hours before proceeding to the tissues (via diapedesis), where they live for about a week, if all goes well. They are produced as a response to acute body stress, whether from infection, infarction, trauma, emotional distress, or other noxious stimuli. When called to a site of injury, they phagocytose invaders and other undesirable substances and usually kill themselves in the act of doing in the bad guys. Normally, the circulating neutrophil series consists only of band neutrophils and segmented neutrophils, the latter being the most mature type. In stress situations (i.e., the acute phase reaction), earlier forms (usually no earlier than myelocytes) can be seen in the blood. This picture is called a left shift. The band count has been used as an indicator of acute stress. In practice, band counts tend to be less than reliable due to tremendous interobserver variability, even among seasoned medical technologists, in discriminating bands from segs by microscopy. Other morphologic clues to acute stress may be more helpful: in the acute phase reaction, any of the neutrophil forms may develop deep blue cytoplasmic granules, vacuoles, and vague blue cytoplasmic inclusions called D?hle bodies, which consist of aggregates of ribosomes and endoplasmic reticulum. All of these features are easily seen (except possibly the D?hle bodies), even by neophytes. The normal range for neutrophil (band + seg) count is 1160 - 8300 /?L for blacks, and 1700 - 8100 /?L for other groups. Keeping in mind the lower expected low-end value for blacks will save you much time (and patients much expense and pain) over the course of your career. Obesity and cigarette smoking are associated an increased neutrophil count. It is said that for each pack per day of cigarettes smoked, the granulocyte count may be expected to rise by 1000 /?L. B. Monocytes These large cells are actually more closely related to neutrophils than are the other granulocytes, the basophil and eosinophil. Monocytes and neutrophils share the same stem cell. Monocytes are to histiocytes (or macrophages) what Bruce Wayne is to Batman. They are produced by the marrow, circulate for five to eight days, and then enter the tissues where they are mysteriously transformed into histiocytes. Here they serve

The Bushido Code

The Bushido Code The Samurai's Tale, a book written by Erik Haugaard, portrays a perspicuous image of Japanese society in Medieval Japan. The Bushido Code, a code of conduct which stresses 6 values and is followed by all samurai, plays an important role in this book. The most prominent of these values are loyalty, courage, and honor.To begin with, loyalty, or being faithful to one's lord, is an important value because it strengthens a lord's rule over his lessers. "Your lord is like your father, you must follow him wherever he leads," (p.119) Wada Kansuke pointed out to Taro. Even though Taro may sometimes disagree with Lord Akiyama, he should still remain loyal to him. In a like manner, Lord Akiyama thought that Katsuyori wasn't as skilled as his father, but he remains loyal to Katsuyori because he was Takeda Shingen's son. Even though Lord Akiyama disagrees with Katsuyori, he follows his orders so the Takeda generals will not fight amongst themselves trying to become the next ruler of the Takeda.ta ro dares you to take his beloved stickIn addition, the ronin bandit was very loyal to Lord Obu in spite of his lord's revolt against Takeda Shingen. "I serve Lord Obu and no-one else," (p.116) the ronin bandit objected when Taro suggested that he should join Lord Akiyama. Although joining Lord Akiyama could save his life, the ronin refused because of his loyalty to Lord Obu. Loyalty is what unites the Takeda and other tribes from the lowly peasant to the powerful general.Courage is equally important since it is what enables the samurai to fight each other on the battle field or there would be no fighting because the samurai wouldn't be brave enough to risk their lives. Throughout The Samurai's Tale, Taro shows bravery by doing several remarkable feats. "Fate cheated me of...

A Price Discrimination and a Single-Pricing Strategy Essay

A Price Discrimination and a Single-Pricing Strategy - Essay Example Instead of charging a uniform price to everyone, the cable TV company can think in terms of charging the customers with respect to the number of paid channels they would like to watch. For some customers may not like sports channels and some others may not like movie channels. The cable TV company can think in terms of allowing the customers to select the channels they would like to watch and based on that the company can decide the prices of the service. Thus customers will get much more flexibility in selecting channels and controlling their budget for watching television channels. At the same time, it should be noted that the cable TV company may not lose any revenue since more customers will come forward to purchases such services because of the increased flexibility in selecting channels. In a perfectly competitive market, sellers may not get the freedom to fix the price. If they set a price above the market price, nobody will buy their product in a competitive market. In short, they will get only a normal profit in the long run. Some firms may fix higher prices for their products if the competition is less. Such firms will get abnormal profits in the short run. The abnormal profit earned by a single firm in a market will encourage other forms to enter the market and therefore supply will increase and the price would come down. Long run average cost curves represent the economies of scale and diseconomies of scale as far as a firm is concerned. Economies of scale mean the ability of a firm to reduce the unit price of a product with the help of bulk production.