Transplants

The transplant is a complex medical treatment. With transplants organs, tissues or cells of a healthy person can replace organs, tissues or cells of a sick person.

In some cases, this action serves to save a person's life, in others they help to improve the quality of life, or both.

Blood transplantation is the first example of transplant of which we have information throughout history.

As scientific knowledge has progressed, it has become possible to transplant almost anywhere on the body, such as the first heart transplant performed in 1966 in Minneapolis by Dr. Richard C. Lilehey.

This treatment in now widely used in medicine and greater risk the rejection, because if the transplant is from another person, the body cannot recognize the organ as its own, producing rejection, expulsion and infection of the organ.

GUM

Chewing gum is a type of confection traditionally made of chicle, a natural latex product, or synthetic rubber known as polyisobutylene. For reasons of economy and quality, many modern chewing gums use rubber instead of chicle. Chicle is nonetheless still the base of choice for some regional markets, such as in Japan.

HISTORY OF THE GUM

Chewing gum in various forms has existed since at least the Neolithic period. 5,000-year-old chewing gum with tooth imprints, made of birch bark tar, has been found in Kierikki, Yli-Ii, Finland.

The ancient Aztecs used chicle as a base for making a gum-like substance. Women in particular used this gum as a mouth freshener. Many other cultures have chewed gum-like substances made from plants, grasses, and resins.

In 1848, John B. Curtis developed and sold the first commercial chewing gum called The State of Maine Pure Spruce Gum.

Chicle gum, and gum made from similar latexes, had a smoother and softer texture and held flavour better

NEED TO CHEW

The need for chewing has been studied by psychologists and anthropologists. With this research, it was discovered that gum chewing reduces muscular tension and helps you relax.

HOW IS GUM MADE?

1. In a container 500 kilos of pasta are mixed and additives are added to give colour and flavour.

2.The pasta goes to a mill, where it is flattened and shaped into leaves.

3. The sheets pass a cutter, which cuts it into the size you want.

4. The gum is packaged in coloured paper by an automatic machine.

Contraceptives

The pill appears in the 60s and it was the first contraceptive.

The contraceptive pill was only supered by the abstinence or a surgical operation.
The American biologist Gregory Goodwin Pincus (1903-1967) is considered the father of the contraceptive pill.

In 1953 he and Chang Min Chueh used rabbits as guinea pigs to prove a contraceptive made with hormones.

But today there isn't any a contraceptive that always works, here are the percentages of mistake:

-contraceptives pills: 1%-3%
-male condom: 12%
-female condom: 15%-21%
-vasectomy: less than the 1%
-Feminine sterilization: 0.04%