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991.
The T-cell receptor (TCR) repertoire plays an important role in shaping specific immune responses. Genetic polymorphisms at the TCR locus, in both constant and variable regions, seem to represent an important mechanism for generating inter-individual and inter-population differences. Considering the scarcity of immune parameters characterized for normal human populations, we decided to determine the frequency of two TCRBV polymorphisms (located in the TCRBV3S1 and TCRBV18 gene segments) in two ethnically distinct groups of the general Brazilian population. Both polymorphisms are related to the expression of these segments at the T-cell surface and can consequently modulate the T-cell repertoire, potentially modifying the capacity of a given individual to develop an immune response. These DNA polymorphisms were analysed in material obtained from adult, normal South-American Caucasoid and Black individuals. A total of 139 individuals were analysed for the TCRBV3S1 and 141 for the TCRBV18 gene segment polymorphisms. The data indicated statistically significant differences in allelic frequencies for the two ethnic groups analysed, suggesting that any correlation between TCR usage or T-cell repertoire and development of a given disease should take in account the ethnic origin of the population studied.  相似文献   
992.
993.
Background: General anesthetics inhibit evoked release of classic neurotransmitters. However, their actions on neuropeptide release in the central nervous system have not been well characterized.

Methods: The effects of representative intravenous and volatile anesthetics were studied on the release of sulfated cholecystokinin 8 (CCK8s), a representative excitatory neuropeptide, from isolated rat cerebrocortical nerve terminals (synaptosomes). Basal, elevated KCl depolarization-evoked and veratridine-evoked release of CCK8s from synaptosomes purified from rat cerebral cortex was evaluated at 35[degrees]C in the absence or presence of extracellular Ca2+. CCK8s released into the incubation medium was determined by enzyme-linked immunoassay after filtration.

Results: Elevation of extracellular KCl concentration (to 15-30 mm) or veratridine (10-20 [mu]m) stimulated Ca2+-dependent CCK8s release. Basal, elevated KCl- or veratridine-evoked CCK8s release was not affected significantly by propofol (12.5-50 [mu]m), pentobarbital (50 and 100 [mu]m), thiopental (20 [mu]m), etomidate (20 [mu]m), ketamine (20 [mu]m), isoflurane (0.6-0.8 mm), or halothane (0.6-0.8 mm).  相似文献   

994.
The main point of this study resides in comparing the efficiency and the disadvantages of using cefazoline and cotrimoxazole in the prevention of post-surgery infections of the low urinary tract. 91 patients who were about to undergo urologic surgery were divided in three groups for randomisation. 31 patients received 500 mg of intramuscular cefazoline every eight hours, the day before surgery, the day of surgery and five days following surgery. 30 others received 800 mg of intramuscular sulfametoxazole and 160 mg of trimetoprime every 12 hours during the same lapse of time. The third group of 30 patients did not receive any antibiotics. Age, sex, clinical pathology needing surgery and indwelling catheter were the same in the three groups. The group treated by cefazoline, presented 5 post surgery infections among which 3 transitory fevers and 2 isolated bacteriurias. In the group treated by cotrimoxazole, there were 7 post surgery infections among which 3 fevers and 4 isolated bacteriurias. Tolerance in both cases was similar. In the control group, there were 19 post-surgery infections with 2 cases of sepsis, 14 transitory fevers and 3 isolated bacteriurias. These results show the importance of antibiotic prophylaxy in urologic surgery of the low genital tract whether the patient has a urethral catheter or not and whatever the type of urologic surgery. But, there is no significant difference between cefazoline and cotrimoxazole.  相似文献   
995.
Cancer Chemotherapy and Pharmacology - Addition of solid doxorubicin or solutions to pre-formed liposomes proved to be the optimal method for incorporating the drug into liposomes whilst...  相似文献   
996.
We describe a simple direct extraction method for the gas-liquid chromatography determination of serum valproic acid. The working range for the assay is 2-180 mg/L and our within-run precision was 5.8 and 4.3% at the 40 and 90 mg/L concentrations respectively. Hemolyzed and lipemic sera as well as samples from patients with hyperbilirubinemia and from patients with decreased renal function were put through the assay and no interfering peaks were noted. Interference occurred when teflon-lined screw caps were used during the extraction step. The method was proven to be accurate by linear regression analysis of samples containing weighed-in amounts of valproic acid. The above assay was compared to an enzyme immunoassay technique (EMIT). The working range for the latter is 10-150 mg/L and the with-run precision was 10.8 and 5.9% and 90 mg/L concentration respectively. Samples were run by both the gas-liquid chromatograph and enzyme immunoassay methods and gave very similar results over the range 16-139 mg/L.  相似文献   
997.
998.
1 Contractile responses of canine intestinal circular and longitudinal muscles to field stimulation (20 Hz, 1 ms, 30 V/cm, for 5 s) were inhibited by treatment with atropine (0.1 microgram/ml), indicating that the response to field stimulation was mediated by acetylcholine (ACh). 2 Prostaglandins E1 (PGE1), PGE2 and PGF2 alpha inhibited the response of circular but not longitudinal muscle to field stimulation, although PGF2 alpha was less effective than PGE1 and E2. 3 PGE1 was much less active in inhibiting the response of circular muscle to ACh than to field stimulation, suggesting that prostaglandins might act predominantly at prejunctional sites to prevent the release of ACh. 4 Indomethacin (1 microgram/ml) potentiated the response of circular muscle but not longitudinal muscle to field stimulation. 5 Release of PGE-like compounds from circular muscle only, was increased by field stimulation at 20 Hz (total of 1000 pulses) and ACh (10 micrograms/ml), but not by a lower frequency (2 Hz, total of 2400 pulses) which produced only a slight contraction. This finding may indicate that prostaglandins were released predominantly from the muscle. 6 Prostaglandins may exert a negative feedback mechanism of excitatory transmission in circular muscle but not in longitudinal muscle of canine small intestine.  相似文献   
999.
Summary In cases where a reconstruction of defects in the larynx, oral cavity, the pharynx or in the ear region has been performed using skin flaps, a temporary fistula is formed at the point of entry.This fistula can be closed later after the flap has taken and the flap pedicle dissected.We would like to demonstrate with some examples that with the use of deepithelisation it is possible to achieve a primary wound closure. This way no temporary fistula results and additional surgery is avoided in many cases.Furthermore flap deepithelisation offers a way to bring good vascularised tissue under the skin and cover subcutaneous defects, for example those after radiotherapy.

Die Veröffentlichung des Manuskripts soll in Laryngol Rhinol Otol (Stuttg) erfolgen  相似文献   
1000.
The presence of accessory channels between the liver and extrahepatic bile ducts has long been recognised by anatomists and the division of such ducts may be a cause of bile leakage following cholecystectomy. However, visualisation of accessory bile ducts at operation is difficult as they are often small and sometimes less than 1 mm in diameter. Cholangiography has been used to help in the identification of accessory ducts in 50 patients included in a prospective trial. X-rays were taken after dissection of the gall bladder from its bed and extravasation of contrast was seen on five occasions (10%) suggesting leakage from divided accessory ducts. The identification of damage to accessory bile ducts in 10% of patients suggests that this may occur more frequently than previously supposed.  相似文献   
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