Blockage of uterine tubes, often the consequence of pelvic inflammatory disease.
Anatomical problems, eg. Retroversion of the uterus.
Endocrine factors, any abnormalities of the glands and hormones governing the menstrual cycle can interfere with, for example, ovulation or the uterine cycle.
Low body weight. Endometriosis.
All warm blooded animals are susceptible to the rabies virus, which is endemic in many countries but not in Britain. The main reservoirs of virus are wild animals, some of which may be carriers. There may infect domestic pets which then become the main source of human infection. The virus multiply in the salivary glands and are present in large number in saliva. They enter the body throug skin abrasions and are believed to travel to the brain along the nerves. The incubation period varies from about 2 weeks to several months, possibly reflecting the distance viruses travel between the site of entry and the brain. Extensive damage to the basal nuclei, mid brain , medulla oblangata and the posterior root ganglia of the peripheral nerves causes meningial irritation, extreme hyperaesthesia, muscle spasm and convulsions. In the advanced stages muscle spasm may alternate with flaccid paralysis and death is usually due to respiratory muscle spasm or paralysis.
Not all people exposed to virus contract rabies, but in those who do , the mortality rate is high.
This is not a disease in it self. It is a sign of abnormal bilirubin metabolism and excretion. Bilirubin, produced from the breakdown of haemoglobin, is usually conjugated in the liver and excreted in the bile.Conjugation the process of adding certain groups to the bilirubin molecule, makes it water soluble and greatly enhances its removal from the blood , an essential step in excretion.
Unconjugated bilirubin, which is fat soluble has a toxic effect on brain. However it is unable to cross the blood - brain barrier until the plasma level rises above 340mol\1 , but when it does it may cause neurological damage, fits.
Jaundice develops when there is an abnormality at some stage in the metabolic sequence caused by one or more factors.eg..
Excess hamolysis of red blood cells with the production of more bilirubin than the liver can deal with
Abnormal liver function that may cause,
Incomplete uptake of unconjugated bilirubin by hepatocytes
In effected conjugation of bilirubin. Interference with bilirubin secretion into the bile.
Obstruction to the flow of bile from the liver to the duodenum
Inflammation of the glands and prepuce may be caused by a specific or non specific infection. In non specific infections , or balanitis , lack of reproal hygiene is an important predisposing factor,especially if phimosis is present, i.e the orifice in the foreskin is too small to allow for its normal retraction.if the infection becomes chronic there may be fibrosis of the foreskin , which increases the phimosis
This is an acute inflammatory condition of the salivary glands ,especially the parotids. It is caused by the mumps virus .one of the parainfluenza group. The virus is inhaled in infected droplets and during the 18 - 21 day incubation period viruses multiply elsewhere in the body before spreading to the salivary gland. The virus is present in saliva for about 7 days before and after symptoms appear so infection may spread to others during his 2 week period. They may also spread to .
The pancreas, causing pancreatitis.
The testes, causing orchitis after puberty and some times atrophy of the glands and sterility.
The brain, causing meningitis or meningoencephalitis .
Also known as Decubitus ulcers, there accus over pressure points between a bony Prominence and a hard surface. Eg. A bed or chair. When this occurs , blood flow to the affected area is impaired and ischaemia develops initially the skin reddens, and later as ischaemia and necrosis occur the skin sloughs and an ulcer forms that may then enlarge into a cavity. If infection occurs , this can result in septicaemia. Healing takes place by second intention.
Predisposing factors .
There may be extrinsic .eg . Pressure ,shearing forces trauma ,immobility,moisture infection
Intrinsic .eg.poor nutritional status,poor circulation , sensory impairment ,infection, old age.
Compression of a facial nerve in the temporal bone foramen causes paralysis of facial muscles with drooping and loss of facial expression on the affected side .The immediate cause is inflammation and oedema of the nerve but the underlying cause is unknown .The onset may be sudden or develop over several hours .distortion of the features is due to muscle tone on the unaffected side , the affected side being expressionless . Recovery is usually complete within a few months .
Benign tumours
Most breast Tumours are benign .fibroadenomas are the commonest type and occur any time after puberty ,incidence peaks in the third decade .some are cystic and some solid and they usually occur in women nearing the menopause .They may originate from secretory cells .
Malignant Tumours
Most common types of Tumours are usually painless lumps found in the upper outer quadrant of the breast.there is considerable fibrosis around the Tumour that may cause retraction of the nipple and necrosis and ulceration of the overlying skin . It is increasingly common between 35 and 70 yrs .early spread beyond the breast is via lymph to the axillary and internal mammary nodes.local invasion involves the pectoral muscles and the pleura .blood spread metastases may occur later in many organs and bones , especially lumbar and thoracic vertebrae .the causes of breast cancer are not known , but an important predisposing factor appears to be high oestrogen exposure .women with an early menarche , a late menopause , and no pregnancies have a higher than normal risk because they experience more menstrual cycles in their life times and each monthly proliferative phase of the cycle . A genetic component is also likely with close relatives of cancer sufferers having a significantly elevated risk of developing the disease .one precent of all breast cancer occur in men
this is a congenital abnormality which may not be noticed until the onset of mentruation.when complete(imperforate), the hymen forms a barriers in the vagina.blood accumulate in the vagina,uterus and uterine tubes wityh each menstural cycle,and its may enter the periotoneal cavity and cause peritonitis.the uterine tubes may becomes obstructed by coagulated blood,leading to infertility.
Author:someswara
shocks occurs when the metabolic needs of the cells are not being met because of inadequate blood flow.in effects,there is a reducation in circulating blood volume,in blood pressure and n cardiac tisue hypoxia,an inadequate supply of the nutrients and the accumulation of waste products.A number of different types of shock are described:
· hypovolaemic
· cardiogenic
· septic
· neurogenic
· anaphylactic
Hypovolaemic shocks:
this oocurs when the blood volume is reduced by 15 to 25%.reduced venous return and in turn cardiac output may occur following:
· serve haemorrhage whole blood lost
· extensive superficial burns serum is lost and blood cells at the site of the burns are destroyed
· serve vomiting and diarrhoea water and electrolytes are lost
· perforation of an organ allowing its conent to enters the peritoneal cavity(peritonitis)
Cardiogenic shocks:
this occurs in accute heart diseases when the damaged heart muscle cannot maintain an adequate cardiac output,e.g. in myocardial infractionSeptic shocks(bacteraemic,endotoxic)this is caused by severe infections in which endotoxins are released into the circulation from dead gram-negative bacteria,e.g. enterobactreia,pseudomonas. the mode of action of the toxins is not clearly understood.it may be that they cause an apparent reducation in the blood volume because of vasodilation and pooling of the blood in the large veins.this reduces the venous return to the heart and the cardiac output.
Neurogenic shocks(vasovagal attack,fainting):
the cause include sudden acute pain,severe emotional experince,spinal anaesthesia and spinal cord damage.parasympathetic nerve impluse reduce the heart rate,and in turn,the cardiac output.the venous return may also be reduced by the pooling of blood in dilated veins.these changes effectively reduce the blood supply to the brain,causing fainting.the period of unconsciousness is usually of short duration.
Anaphylactic shock:
in the allergy reaction an antigens interacts with an antibody and a variety of response can occurs .in severe cases,the chemicals released,e.g.histamine,bradykinin,produce widespread vasodilation and constriction of bronchiolar smooth muscle(bronchospam).the vasodilation profoundly reduces the venous return and the cardiac output resulting in the tissue hypoxia.bronchospasm reduces the amount of the air entering the lungs,increasing the tissue hypoxia.
author:someswara.
