PubMed Health⌕ Search

Biomedical subjects

Z H Khan

Publications and source records attributed to Z H Khan.

36 records · Page 2Linked to original sources
PubMed1990

Post-operative sputum retention treated by minitracheostomy--a ward procedure?

Cricothyroidotomy, using the percutaneous 'minitracheotomy' technique, was performed in 67 patients (55 for sputum retention, two for endobronchial rupture of an empyema, 10 prophylactically). In two patients the cricothyroid membrane was penetrated with considerable difficulty, and in one further patient insertion was not possible due to calcification of the cricothyroid membrane. One patient required exploration of the insertion site because of bleeding. Two patients inhaled the 'Mark 1 Minitrach' device and required urgent bronchoscopic removal. In those patients undergoing successful cricothyroidotomy, there was a dramatic improvement in respiratory distress. There were no deaths related to the insertion of the minitracheotomy device in this series.

Adolescent↗
PubMed1988

Prevalence of cryptosporidiosis in Dammam and Alkhobar, Saudi Arabia.

This report presents results from a 6-month study over the period 16 November 1986 to 15 May 1987 which was designed to investigate the prevalence of cryptosporidiosis in Dammam and Alkhobar, Saudi Arabia. A total of 209 stool specimens from children and 112 from adults with diarrhoea were examined. Only two (1%) of the children, both aged 2 years, were positive for Cryptosporidium spp. Giardia lamblia was found in 13 (4%) cases and was found to be the most common protozoan parasite, whereas Salmonella spp. was seen in 19 (6%) cases. Stool specimens were examined for rotavirus from children under 2 years of age; 31 (41%) of the specimens were positive.

Adult↗
PubMed1967

Observations on the flight activities of Culex pipiens fatigans in Rangoon, Burma.

Knowledge of the behaviour of a vector is often of value in devising suitable methods for assessing control or eradication measures. Flight behaviour is particularly important, since it is during this activity of a mosquito that trapping is possible. Trapping data have proved useful in the assessment of the action of insecticides on the vectors of malaria, and there is no reason why this should not also be the case with the vectors of filariasis.In this paper the difficulties of trapping Culex pipiens fatigans by conventional means are stressed. Moreover, since flight is a dynamic process, the interpretation of flight activities from data collected by traps, which are static, is difficult. Nevetheless, the results presented, however inadequate, show that adult C. p. fatigans move about more, both by day and at night, than is usually suspected and that the subject would repay closer study.

Animals↗
PubMed1967

Dispersion studies of Culex pipiens fatigans tagged with 32P in the Kemmendine area of Rangoon, Burma.

The flight range and the dispersion of a vector are important factors when control or eradication measures are being considered and when general biological information is desired. The present work on Culex pipiens fatigans was carried out under conditions where breeding is intensive and housing congested. The radioactive tagging method adopted seemed to be harmless to the mosquito and gave excellent results.Radioactive adults emerging under normal conditions from larvae collected in the centre of the Kemmendine Experimental Area did not appear to differ in flight behaviour from radioactive adults released at one time in the centre. Mosquitos of both sexes dispersed fairly evenly in all directions from the release point; this fact is likely to be of practical value in control and biological experiments. Some mosquitos even crossed a river over one-third of a mile (500 m) wide and specimens were collected by hand more than (1/2) mile (800 m) from the release point without the use of lures or traps.The method also yielded valuable data on the daily mortality of adults and on the total mosquito population in the area. There seems little doubt that the radioisotope tagging technique can be a most valuable weapon in the hands of the biologist or epidemiologist.

Animals↗
PubMed1967

Time of arrival of gravid Culex pipiens fatigans at an oviposition site, the oviposition cycle and the relationship between time of feeding and time of oviposition.

One of the most important activities in a female mosquito's life is the flight to the breeding place and the subsequent deposition of eggs. During this phase, motivated by endogenous and exogenous stimuli, the female is particularly exposed and susceptible to attack. It is therefore important to investigate these episodes in the gravid female's life.The work reported in this paper shows that gravid Culex pipiens fatigans females are easily trapped over breeding-water; there are two peaks in the arrival at a breeding site, one just after sunset and the other at sunrise. The oviposition cycle is biphasic, the two peaks coinciding, in calm weather, with the two arrival peaks; wind and rain cause marked disturbances in the oviposition cycle.The mean duration of the gonotrophic cycle depends on the time of feeding; this finding is of practical importance since the length of the cycle is often used to calculate the daily survival rate of adult mosquitos. It appears that oviposition is stimulated by a change in light: from light to dark for mosquitos ovipositing in the evening and from dark to light for those ovipositing in the morning.Apart from revealing some hitherto unknown behaviour patterns, the techniques evolved could also be used in the assessment of mosquito populations and hence the effects of control measures.

Animals↗
PubMed1967

Outdoor resting of Culex pipiens fatigans in Rangoon, Burma.

The sites occupied by resting adult mosquitos are of importance, since they may be accessible to treatment with insecticide. It has usually been assumed that Culex pipiens fatigans feeds and rests indoors, thus making itself vulnerable to indoor spraying. However, work in the Kemmendine Experimental Area of Rangoon, Burma, has now shown that many C. p. fatigans rest out of doors in a variety of shelters. The lower parous rate in outside catches as compared with indoor catches tends to confirm the view that newly hatched C. p. fatigans rest out of doors for some time before setting off to feed. The percentage of infected mosquitos is remarkably constant from site to site and from month to month and does not differ significantly from that obtained in indoor resting catches or on bait out of doors. It appears that the possibility of acquiring infection out of doors will have to be seriously considered in any anti-filariasis campaign.

Animals↗
PubMed1967

The duration of egg, larval and pupal stages of Culex pipiens fatigans in Rangoon, Burma.

Laboratory experiments to determine the duration of the immature stages of Culex pipiens fatigans were carried out because such information is important from the point of view of control by larvicides. At a temperature of 25.1 degrees C+/-0.7 degrees C the mean incubation period is 27.11+/-0.57 hours. Females spend a longer time in the pupal stage than males (34.16+/-0.74 hours and 32.95+/-0.75 hours, respectively, at 28.6 degrees C+/-0.8 degrees C; there is no 24-hour pupating or emerging rhythm. The duration of larval life is longer for the female (135.3+/-4.4 hours) than for the male (118.4+/-2.4 hours). Larvae that take a long time to pupate also take a long time to emerge. Withholding of food for a few hours from first-stage larvae increases the duration of larval life but does not affect that of pupal life. These observations on the differences between the sexes in the duration of larval and pupal life are in agreement with observations made on Aedes aegypti in Uganda.

Animals↗
PubMed1967

Cane-sugar feeding in Culex pipiens fatigans.

The relatively poor results that have been obtained in controlling or eradicating Culex pipiens fatigans, the urban vector of Wuchereria bancrofti, have made it necessary to obtain as much information as possible about its biology. In this paper the unexpected finding of the influence of cane sugar in delaying oviposition in the gravid female is reported. This is an important finding for those who are investigating the biology of this mosquito in the laboratory and who make use of the age-old practice of keeping adult mosquitos alive by feeding them cane sugar. It is also reported that under certain conditions extensive cane-sugar feeding takes place in nature and it seems possible that this habit may have unsuspected repercussions on behaviour and physiology beyond the confines of the laboratory. One possible development would be the isolation of the attractant present in unrefined sugars and its use in traps in order to assess mosquito populations in the field.

Animals↗
PubMedDate not supplied

Multimedia in health.

Explore the source record for details and available documents.

Computer-Assisted Instruction↗