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121.
122.
Digital clubbing has been a well recognised feature of several distinct clinical conditions, including respiratory, cardiac, and gastrointestinal diseases since the Hippocratic era. However, clubbing associated with Beh?et's disease has not been reported before. We describe a case of clubbing in a young man with Beh?et's disease, in the absence of any other apparent aetiology and propose that clubbing might be an accompanying feature of Beh?et's disease.  相似文献   
123.
The prevalence of epilepsy in developing countries is much higher than in developed ones. Some of the highest prevalence rates in developing countries have been reported from tropical Africa where parasitic infections are endemic. This work was carried out to assess the effect of different parasitic antigens on the activity of cerebral cortex in rats. Nine crude antigens were used: Adult Fasciola, adult S. mansoni, hydatid cyst, T. spiralis, E. histolytica, Acanthamoeba spp. G. lamblia, Cryptosporidium spp. and crude antigen of T. gondii. All the parasitic antigens induced electroencephalographic changes compared with baseline tracings.  相似文献   
124.
BACKGROUND: Recent studies have questioned the use of aggressive fluid resuscitation after uncontrolled arterial hemorrhage until the bleeding is controlled. However, it remains unknown whether resuscitation after hemorrhage from a venous origin (usually nonaccessible to surgical intervention) has any beneficial or deleterious effects on regional perfusion. The aim of this study, therefore, was to determine whether increased volume of fluid resuscitation after uncontrolled venous hemorrhage improves hemodynamic profile and regional perfusion in various tissues. MATERIALS AND METHODS: After methoxyflurane anesthesia and midline laparotomy, both lumbar veins in the rat were severed, which resulted in lowering the mean arterial blood pressure to approximately 40 mm Hg. This pressure was maintained for 45 minutes by allowing further bleeding from the lumbar veins. The abdominal incision was then closed in layers and the animals received either 0, 10, or 30 mL of lactated Ringer's solution intravenously over a period of 60 minutes. Cardiac output and regional blood flow were determined by radioactive microspheres immediately or at 1.5 hours after the completion of resuscitation. RESULTS: Fluid resuscitation with 10 or 30 mL lactated Ringer's solution increased mean arterial blood pressure and cardiac output immediately after resuscitation compared with the nonresuscitated animals. At both time points, regional perfusion in the heart, kidney and intestines remained significantly decreased compared with the sham values, irrespective of the volume of fluid resuscitation. Moreover, no further improvements in hemodynamics or regional perfusion occurred when volume resuscitation was increased from 10 mL to 30 mL. Total hepatic blood flow, however, increased with 10 mL lactated Ringer's solution compared with the other hemorrhage groups and the increase was evident even at 1.5 hours after resuscitation. CONCLUSIONS: Fluid resuscitation after uncontrolled venous bleeding transiently increased cardiac output and mean arterial blood pressure compared with nonresuscitated animals. Moderate fluid administration, i.e., 10 mL, however, did increase total hepatic blood flow. In contrast, increasing the resuscitation volume to 30 mL did not improve hemodynamic parameters or regional perfusion. Thus moderate instead of no resuscitation or larger volume of resuscitation is recommended in an uncontrolled model of venous hemorrhage.  相似文献   
125.
In the present study two cytogenetic parameters were used to evaluate the DNA damage induced by low doses (1 up to 40 rad) of X-ray irradiation in G0 human lymphocytes. These parameters were the frequency of chromosomal lesions in G2 and the length of this cell cycle phase. The frequency of chromosomal lesions in G2 was determined by scoring the number of chromosomal aberrations in G0 irradiated lymphocytes post treated with two inhibitors of G2 repair mechanisms: caffeine and 3-aminobenzamide. A dose-dependent increase in chromosomal aberrations yield was detected in G0 lymphocytes X-ray irradiated with or without post treatment with these two DNA repair inhibitors during G2. Nevertheless, the dose response in this latter condition was higher than the one detected in control cells, indicating that the increase of irradiation dose in G0 lymphocytes produces an increment in the number of DNA lesions arriving to be repaired in G2. The analysis of the dose-response relationships for G2 length showed an statistically significant X-ray dose-dependent increase (G2 delay) from 2.5 up to 40 rad and a positive correlation between G2 delay and the frequency of chromosomal lesions in G2. These results suggest that the DNA lesions induced by low doses of X-irradiation in G0 lymphocytes may be higher than that detected by the standard method (control conditions) and may be responsible for an increase in G2 length. We propose, therefore, that an analysis of these two cytogenetic parameters can improve the evaluation of the DNA damage induced by low doses of X-rays irradiation in G0 cells.  相似文献   
126.
The potentiometric anion selectivity of polymer membrane-based electrodes formulated with a palladium organophosphine complex (benzylbis(triphenylphosphine)palladium(II) chloride) as the membrane active component is examined. The electrode is shown to exhibit a non-Hofmeister selectivity pattern with a significantly enhanced response toward nitrite over the concentration range of 10 microM-10 mM (log-linear range) and a detection limit 5.0 microM. The effect of lipophilic anionic (tetraphenylborate derivatives) and cationic (tetraalkylammonium) site additives within the membrane on the anion selectivity is examined in detail. Addition of both cationic and anionic sites is shown to improve potentiometric anion selectivity, suggesting that the palladium complex may operate simultaneously as a neutral and charged carrier-type ionophore within the polymer membrane phase. Using optimal membrane formulations (with added 20-30 mol % cationic sites), the sensors prepared with the palladium complex do not exhibit proton/hydroxide response in the range of pH 3.5-12, a potential advantage over previously reported nitrite electrodes prepared with Co(III) corrins and porphyrin complexes.  相似文献   
127.
Hyperhomocysteinemia, either fasting or after methionine loading, may contribute to the increased incidence of cardiovascular disease events experienced by renal transplant recipients. Limited data are available on fasting homocysteine (Hcy) levels, and none on postmethionine-loading Hcy levels, in these patients. We assessed the prevalence and potential determinants of fasting and postmethionine-loading hyperhomocysteinemia in 29 stable renal transplant recipients and 58 age- and sex-matched, population-based controls free of renal disease with serum creatinine levels of 1.5 mg/dL or less. Total (t) plasma Hcy was determined fasting and 2 hours after methionine loading, along with fasting determinations of the B-vitamin cofactors/substrates for Hcy metabolism, ie, pyridoxal 5'-phosphate, B-12, and folate and serum creatinine. Geometric mean fasting (18.1 versus 9.8 microM, P < .001) and postmethionine-loading increase (22.0 versus 15.2, P = .001) in tHcy levels were significantly greater in the renal transplant recipients, as were the prevalence odds (with 95% confidence intervals) for fasting [14.8 (3.4-64.7)], postmethionine loading [6.9 (1.5-32.8)], combined fasting and postmethionine-loading [18.0 (2.3-142.1)] hyperhomocysteinemia, and inadequate circulating folate [4.2 (1.1-16.5)] or pyridoxal 5'-phosphate [3.2 (0.9-11.0) status. Correlation analyses suggested important potential relationships between creatinine and both fasting (+0.64, P < .001) and postmethionine-load increase (+0.38, P = .045) in tHcy, folate and fasting (-0.41, P = .025) tHcy, and pyridoxal 5'-phosphate and postmethionine-loading increase (-0.33, P = .091) in tHcy. We conclude that there is an excess prevalence of fasting and postmethionine-loading hyperhomocysteinemia in stable renal transplant recipients. Renal function is related to both fasting and postmethionine loading-hyperhomocysteinemia, inadequate folate status is associated with fasting hyperhomocysteinemia, and inadequate vitamin B-6 status may be related to postmethionine-loading hyperhomocysteinemia in this patient population.  相似文献   
128.
Ultrasound scans were made of the hips of 209 neonates born consecutively over a two-week period. Of the 418 scans, 62 images were selected at random and 25 of these were duplicated to give a total of 87 scans. These static images were then presented to five experienced observers who each made nine different assessments and measurements. Interobserver and intraboserver agreement was calculated and expressed as kappa values. Our results showed poor reliability on both counts.  相似文献   
129.
Analysis of suicide mortality in New South Wales, Australia is undertaken with reference to marital status and occupational status between 1986-89/90 and with reference to the principal means of committing suicide. Not currently married male manual workers were particularly at risk although marital status variations were significant with both genders and at different ages. Between 1985-91 male suicide mortality rates were significantly higher in inland non-metropolitan regions, especially among younger men, and were higher in inner areas of metropolitan Sydney. While there were no significant variations by marital status in the means of committing suicide there were variations between genders, and there were regional and social class variations in the use of guns with males. The use of guns was a factor in the elevated suicide mortality levels among inland rural youth and men, and among farmers and transport workers while the use of poisons was also significant with these occupational groups. The use of poisons was greater among persons committing suicide in the areas of elevated mortality in inner Sydney and the use of guns much lower.  相似文献   
130.
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