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41.
Donald M. Campbell Gerald I. Forbes 《International journal of environmental health research》1994,4(2):86-92
The prevention of the spread of disease by drinking water relies on a tripartate arrangement among the supplier, the regulator and their medical advisers. This paper describes the role of Public Health Medicine in Scotland in preventing a ‘significant risk to health’ from potable water. The legislative framework is highlighted. The rationale of water monitoring is examined and the role of Consultant in Public Health Medicine. The concept of Significant Medical Risk Values is introduced and their derivation, uses, and levels presented. 相似文献
42.
Oxidative breakdown of octanoic acid is maintained in patients with cirrhosis despite advanced disease 总被引:1,自引:0,他引:1
M. Van de Casteele A. Luypaerts † B. Geypens † J. Fevery Y. Ghoos† & F. Nevens 《Neurogastroenterology and motility》2003,15(2):113-120
As an octanoic acid 13CO2 breath test is frequently used to test gastric emptying of solid food, the purpose of the present study was to study whether oxidative breakdown of octanoic acid is affected by severe liver disease. The design of our study was twofold. First, cirrhotic patients (n = 82) of varying severity were compared with healthy controls (n = 17). Values of half-time, time point of maximal expiration and cumulative recovery of octanoic acid breath tests (OBT) were not significantly different between them. Secondly, cirrhotic patients (n = 10) were studied before placement of transjugular intrahepatic portosystemic shunt, 4-7 days later and 1-2 months later. Values of half-time, time point of maximal expiration and cumulative recovery of consecutive OBTs did not change significantly. The OBT may therefore be a suitable test in the future to detect delayed gastric emptying of solids in cirrhotic patients with reduced liver function and portal hypertension. 相似文献
43.
A. Parthasarathy N. Sumathi R. Manoharan C. D. Natarajan R. Narmada B. R. Santhanakrishnan 《Indian journal of pediatrics》1987,54(5):779-784
Tuberculous infection among children continues to be a significant cause of morbidity. The symptom complex are so variable
among children that the final diagnosis often rests on the laboratory tests. Proper interpretation of the tests, specially
tuberculin test and radiographic studies, are necessary for establishing correct diagnosis. The usefulness of tuberculin test
in both unimmunized and BCG vaccinated children is highlighted. BCG accelerated response as a test should be reserved for
identifying serious form of pulmonary disease or CNS tuberculosis when the tuberculin test is negative. Radiographic assessment
may be sensitive in some instances but not always specific and hence needs cautious interpretation. Tuberculosis among BCG
vaccinated children though not uncommon, needs proper documentation. Current trends in the management of tuberculosis including
CNS forms are briefly outlined. 相似文献
44.
M. Markianos G. Sakellariou E. Bistolaki 《Journal of neural transmission (Vienna, Austria : 1996)》1991,83(1-2):37-42
Summary The prolactin response to 5 mg haloperidol i.m. was studied in 12 schizophrenic patients in a drug-free state and after a month treatment with haloperidol, as a possible index of dopamine receptor sensitivity and occupancy. Blood samples were taken at times 0, 60, 90 and 120 minutes. The increase in PRL observed in the drug-free state disappeared after drug treatment. The PRL plasma levels after treatment with 60 mg haloperidol per os were higher than the maximal PRL responses after 5 mg i.m. The increases in baseline PRL caused by the treatment correlated positively to the reduction in the BPRS score. The test was also performed in a group of 11 patients chronically treated with haloperidol during a daily dose of 60 mg, and 15 days after reduction of the dose to 30 mg. PRL increases after 5 mg haloperidol i.m. were observed only after reduction of the dose. It is suggested that the prolactin response to haloperidol is an index of the occupancy of receptors that are involved in the PRL releasing mechanisms, and could be used to verify their blockade by the neuroleptics, especially in patients that do not respond positively to drug treatment. 相似文献
45.
46.
K Kamakura S Ishiura S Imajoh N Nagata H Sugita 《Journal of neuroscience research》1992,31(3):543-548
The ubiquitous existence of calcium-activated neutral protease (CANP, calpain), an enzyme whose activity is regulated by calcium ions and a specific endogenous CANP inhibitor (calpastatin), is well known. Although there has been much investigation concerning the distribution and role of CANP, investigations of the distribution of the CANP inhibitor using immunohistochemical techniques are rare. We made antiserum against a 40K fragment of cDNA corresponding to two C-terminal repeats of rat liver CANP inhibitor expressed in Escherichia coli. Using this antiserum, we examined the distribution of CANP inhibitor in the rat central nervous system by the ABC technique and compared it with the distribution of CANP. Neurons and glias were stained, with the cytosol stained diffusely and the cell membranes stained clearly and strongly. Axons and myelin were stained faintly, but nuclei and vessels were not stained. The distribution of CANP inhibitor was thus found to be similar to that of CANP. 相似文献
47.
Summary. The aim of the present study was to establish a more differentiating indicator of plasma membrane integrity of spermatozoa than the classic version of the hypoosmotic swelling test according to Jeyendraan. Spermatozoa were prepared by density gradient centrifugation (90% Percoll) to select 'fertilization competent' spermatozoa only. After a second washing procedure sufficiently pure sperm cell suspensions were obtained. The volume distributions of these sperm cells were measured with a Coulter Counter at 25 °C after adaptation in 300 mosmolar NaCl solution resp. 150 mosmolar NaCl solution for 5 min. These volume distributions showed significantly different patterns for the isotonic and hypotonic stress situation in the simple salt solution. Moreover, the comparison of the response to hypoosmotic stress showed more than four reproducible characteristic patterns, promising well differentiated results for different sperm populations. The new method for the detection of hypoosmotic swelling effect might be a real and valuable functional parameter. 相似文献
48.
Background: Malignant hyperthermia (MH) susceptibility is diagnosed using halothane-caffeine contracture testing of a muscle sample maintained at 37˚C. However, there has not been a systematic study that examines the effect of different temperatures on the response of normal muscle to halothane and caffeine. We hypothesized that altering bath temperature would modify the contracture responses.
Methods: We obtained muscle samples from 20 patients undergoing surgical procedures of the lower extremities. The samples were dissected into 245 bundles and the bundles were exposed to halothane 3% or incremental caffeine, according to the North American MH group protocol. Several bundles from each patient were simultaneously studied at four different temperatures (22˚C, 30˚C, 37˚C and 44˚C). Each bundle was studied at only one temperature, the muscle samples of 3 patients were simultaneously studied at all four temperatures for halothane and caffeine.
Results: Maximum contracture to caffeine (32 mM) was highest at 37˚C; however, at lower caffeine concentrations (2–4 mM), there was no consistent effect of temperature on contracture response. Likewise, temperature did not alter contracture responses to halothane. The extremes of temperature (22˚C and 44˚C) were associated with lack of twitch in response to electrical stimulation. For the bundles exposed to halothane at 22"C, the absence of a twitch was associated with the presence of a contracture, although these were never above the diagnostic threshold.
Conclusions: We conclude that temperature has little effect on responses of normal muscle to halothane and caffeine. 相似文献
Methods: We obtained muscle samples from 20 patients undergoing surgical procedures of the lower extremities. The samples were dissected into 245 bundles and the bundles were exposed to halothane 3% or incremental caffeine, according to the North American MH group protocol. Several bundles from each patient were simultaneously studied at four different temperatures (22˚C, 30˚C, 37˚C and 44˚C). Each bundle was studied at only one temperature, the muscle samples of 3 patients were simultaneously studied at all four temperatures for halothane and caffeine.
Results: Maximum contracture to caffeine (32 mM) was highest at 37˚C; however, at lower caffeine concentrations (2–4 mM), there was no consistent effect of temperature on contracture response. Likewise, temperature did not alter contracture responses to halothane. The extremes of temperature (22˚C and 44˚C) were associated with lack of twitch in response to electrical stimulation. For the bundles exposed to halothane at 22"C, the absence of a twitch was associated with the presence of a contracture, although these were never above the diagnostic threshold.
Conclusions: We conclude that temperature has little effect on responses of normal muscle to halothane and caffeine. 相似文献
49.
Visual assessment of urethrovesical junction mobility 总被引:1,自引:1,他引:0
The aim of the study was to compare visual assessment of anterior vaginal wall descent with the Q-tip test in evaluating urethrovesical junction mobility. One hundred and eleven patients with prolapse and/or urinary incontinence were examined in the supine lithotomy position with an empty bladder. Maximum straining Q-tip tests and maximum descent of the anterior vaginal wall were measured. Using each centimeter of descent as a cutoff value, the sensitivities, specificities and positive and negative predictive values were compared to those of the Q-tip test. As the cutt-off points were moved distally, specificity increased at the expense of sensitivity. There was no single cut-off point that provided adequate sensitivity and specificity to be clinically useful to replace the Q-tip test. It was concluded that visual assessment of anterior vaginal wall descent does not provide diagnostic accuracy and acceptable sensitivity and specificity to determine urethrovesical junction mobility. Other methods should be employed to assess support.Editorial Comment: Many clinicians claim that they can assess urethrovesical junction mobility visually and thus avoid employing other means, such as the Q-tip test, ultrasonography, bead-chain cystography or fluoroscopy. Montella et al. evaluate a technique of visual assessment of urethrovesical junction mobility based on the International Continence Society's Standardization of Terminology of Female Organ Prolapse and Pelvic Floor Dysfunction as compared to evaluation with the Q-tip test. Their results clearly indicate that this technique (measurement of the descent of point Aa) does not provide adequate sensitivity or specificity in determining urethrovesical junction descent compared to the Q-tip test. Although this technique was only compared to the Q-tip test and not all other modalities available, it is doubtful that visual assessment of anterior wall descent at any level would correspond to urethrovesical junction mobility, as is discussed very succinctly by the authors. 相似文献
50.