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61.
62.
A modified Rieckmann test was developed for assessing chloroquine sensitivity of Plasmodium vivax strains. This test envisages the evaluation of parasite growth with different concentrations of the drug and its comparison with controls, at the end of a 48-hour experimental period. Using this test, 16 strains were assessed for their chloroquine sensitivity. Twelve strains were found to be sensitive, and 4 were resistant to chloroquine.  相似文献   
63.
64.
Primary objective: To determine whether critical flicker frequency (CFF) thresholds are abnormal in individuals with mild traumatic brain injury (TBI) and, if so, if they are correlated with the degree of reported motion and light sensitivity.

Methods and procedures: The foveal CFF threshold was assessed in individuals with mild TBI (n = 18) having varying degrees of reported light and motion sensitivity. Mean CFF values were obtained using the ascending and descending psychophysical method of limits with binocular viewing at 40 cm. A 7-item, rating-scale questionnaire was used to assess the degree of light and motion sensitivity. These parameters were also assessed in a large visually-normal, non-TBI cohort.

Main outcomes and results: CFF in the mild TBI group was not significantly different across age groups from the visually-normal, non-TBI cohort. However, mean CFF among the mild TBI subjects was significantly higher for the 'light sensitive' and 'motion sensitive' sub-groups when compared to the 'not light sensitive' and 'not motion sensitive' sub-groups. The majority of TBI subjects manifested both light and motion sensitivity.

Conclusion: CFF was found to be related to the reported degree of light and motion sensitivity in individuals with mild TBI. Neurological disinhibition as a result of brain injury may be causal of the subjective hypersensitivity to light and motion in the presence of normal CFF.  相似文献   
65.
Mycobactins are a family of membrane-associated siderophores required for Mycobacterium tuberculosis to adapt to its intracellular habitat. These lipophilic siderophores have been recently shown to directly acquire intracellular iron through lipid trafficking. Despite tremendous progress in understanding the assembly-line enzymology of the siderophore biosynthesis, the genes as well as the mechanistic and biochemical principles involved in producing membrane-associated siderophores have not been investigated. Here, we report a biosynthetic locus that incorporates variety of aliphatic chains on the mycobactin skeleton. Cell-free reconstitution studies demonstrate that these acyl chains are directly transferred from a carrier protein on to the epsilon-amino group of lysine residue by an unidentified Rv1347c gene product. The unsaturation in the lipidic chain is produced by a novel acyl-acyl carrier protein dehydrogenase, which, in contrast to the conventional acyl-CoA dehydrogenases, is involved in the biosynthetic pathway. MbtG protein then performs the final N6-hydroxylation step. Genome-wide analysis revealed homologues of N-acyl transferase and MbtG in other pathogenic bacteria. Because iron plays a key role in the development of infectious diseases, the biosynthetic pathway described here represents an attractive target for developing new antibacterial agents.  相似文献   
66.
OBJECTIVES: The diagnosis, pathogenesis, and treatment of piriformis syndrome as a cause of persistent buttock and hip pain after spinal anesthesia are presented in this case report. CASE REPORT: A 29-year-old woman presented 5 days after cesarean delivery with sudden onset of pain in the left buttock and left hip radiating to the posterior knee with fever. She was subsequently diagnosed with piriformis syndrome. CONCLUSIONS: Back pain with radiation into the buttocks after spinal anesthesia is frequently attributed to the spinal procedure itself. However, prolonged sitting and weight bearing in the upright position after cesarean delivery can cause sciatic nerve compression at the sacroiliac joint with concomitant irritation, inflammation, and spasm of the piriformis muscle. Piriformis syndrome is frequently underdiagnosed in the obstetric population. Because the diagnosis of piriformis syndrome is based mainly on clinical signs and symptoms, the clinician must have a high index of suspicion.  相似文献   
67.
Abstract Many of the disorders today are based on the imbalances of immunological processes. This necessitates the search for newer and safer immunomodulators. Thus, the objective of the present study was to explore the immunomodulatory activity of the methanolic extract of Piper betel L. (MPb) (Family: Piperaceae). The MPb consists of mixture of phenols, flavonoids, tannins and polysaccharides. Both in vitro as well as in vivo evaluation was carried out. The effects of MPb on lymphocyte proliferation, interferon-γ receptors and the production of nitric oxide were measured in vitro . Further, the extract at different dose levels was studied in vivo for the humoral and cellular immune responses on mice immunized with sheep red blood cells. P. betel significantly suppressed phytohaemagglutinin stimulated peripheral blood lymphocyte proliferation in a dose-dependent manner. The decrease in antibody titre and increased suppression of inflammation suggests possible immunosuppressive effect of extract on cellular and humoral response in mice. Thus, the MPb could be explored extensively as a therapeutic agent to treat various immune disorders including autoimmune disorders.  相似文献   
68.
Microbiological contamination of blood and blood products is a well-recognised transfusion risk. This study was performed in the blood bank of our oncology centre, with an objective to detect bacterial contamination in our blood products using oxygen consumption as a surrogate marker [Pall Enhanced Bacterial Detection System (eBDS)]. Results revealed that the percentages of failed units were 1.16% for random donor platelets (RDP), 0.81% for single donor platelets (SDP) and 2.94% for packed red blood cells (PRBCs), of which one RDP and one SDP grew coagulase-negative staphylococcus, while one PRBC culture grew Gram-positive bacilli.  相似文献   
69.
To test the hypothesis that lidocaine passage into the central nervous system is a function of free rather than total lidocaine concentration, we examined the effect of serum protein binding on the distribution of lidocaine into brain and cerebrospinal fluid (CSF) in dogs. Six of the 13 dogs studied were pretreated with rifampin to induce a 4-fold increase (P = 0.019) in serum concentration of alpha 1-acid glycoprotein, which is a major binding protein for lidocaine. The dogs were anesthetized and prepared surgically to obtain samples of cortical brain tissue or CSF from the cisterna magna. Lidocaine at a dose of 3 mg/kg was infused intravenously over 15 s. Arterial blood and brain cortex or CSF were sampled serially during a 60-min interval and analyzed for lidocaine content. Unbound or free fraction of lidocaine in serum was measured by equilibrium dialysis. Rifampin pretreatment led to a significant decrease in average serum free fraction of lidocaine, from 0.24 +/- 0.08 to 0.080 +/- 0.030 (P less than 0.001). Total lidocaine concentration in serum was higher, but free lidocaine concentration was lower in the rifampin group. Equilibration of lidocaine between serum and brain or CSF was reached by 10 min after lidocaine administration. Rifampin-pretreated dogs had consistently lower partition ratios of lidocaine between brain and serum or between CSF and serum. A strong and positive correlation between time-averaged brain to serum or CSF to serum ratios and serum free fractions were observed (r = 0.92, P less than 0.001 for brain; r = 0.90, P less than 0.01 for CSF).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
70.
INTRODUCTION: Interferon (IFN)-alpha, used for the treatment of chronic hepatitis C, has rarely been associated with the development of diabetes. Consensus interferon (CIFN), which is used for nonresponders, has not been associated with this complication. We describe the first case of new onset diabetes in a patient on CIFN. CASE: A 50-year-old man with chronic hepatitis C and no prior diabetes was started on IFN-alpha. After 24 weeks with a detectable viral load, he was switched to CIFN. Four weeks later, he presented in diabetic ketoacidosis which resolved with appropriate therapy without any ascertainable etiology (glutamic acid decarboxylase negative). Within 9 months he was off insulin, and is off all diabetic medications with an HgA1c of 5.6% 2 years after the episode.  相似文献   
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