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Treatment guidelines for management of uncomplicated gonorrhoeae have been recently modified owing to alarming upsurge in azithromycin resistance. This study investigated the prevalence and genetic determinants of gonococcal azithromycin resistance in India. Four (5.7%) of 70 gonococcal isolates were resistant to azithromycin. Of 16 isolates investigated for molecular mechanisms of resistance, 13 (81.3%) and 6 (37.5%) isolates exhibited mutations in coding and promoter regions of mtrR gene, respectively. However, ermA, ermB and ermC genes or mutations in rrl gene were absent in all isolates. Azithromycin resistance is low in India posing no immediate threat to use of dual-therapy for syndromic management.  相似文献   
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1,450 nm Long-Pulsed Diode Laser for Nonablative Skin Rejuvenation   总被引:1,自引:0,他引:1  
Doshi Seema N.  MD    Alster Tina S.  MD 《Dermatologic surgery》2005,31(S3):1223-1226
Background:. There has been growing patient demand for laser technology to treat rhytids and to refine skin texture without the associated lifestyle hindrance common to ablative cutaneous procedures. Nonablative laser systems have been developed to meet this need and, in many instances, have replaced ablative lasers as the preferred treatment modality.
Objective:. To review long-pulsed diode laser technology in the treatment of a variety of cutaneous disorders.
Materials and Methods. All publications involving 1,450 nm long-pulsed diode laser technology were reviewed and discussed.
Results. The latest generation of nonablative lasers, in the midinfrared electromagnetic spectrum, selectively targets and heats dermal tissue to stimulate collagen remodeling while sparing the epidermis.
Conclusions. Demonstrating efficacy in the treatment of a wide range of cutaneous disorders, including facial rhytids, acne vulgaris, and atrophic scars, the 1,450 nm diode laser is a useful addition to the nonablative laser armamentarium.  相似文献   
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The effects of morphine tolerance-dependence and abstinence on 5-HT1A receptors in brain regions and spinal cord of the rat were determined. Tolerance to and physical dependence on morphine was induced in male Sprague-Dawley rats by implanting six morphine pellets (each containing 75 mg of morphine free base) during a seven day period. Two groups of rats were used for binding studies. In one group the pellets were left intact (tolerant-dependent) and in the other they were removed (abstinent). Rats were killed, and spinal cords and brains were excised. Brain was dissected into seven regions (amygdala, hippocampus, hypothalamus, striatum, midbrain, pons + medulla and cortex). 5-HT1A receptors were characterized by using [3H]8-hydroxy-di-n-propylaminotetralin [( 3H]DPAT) as the ligand and unlabelled 5-HT to determine the non-specific binding. In morphine and placebo tolerant-dependent rats the binding of [3H]DPAT to 5-HT1A receptors in brain regions and spinal cord did not differ. The Bmax value of [3H]DPAT in the hypothalamus of morphine abstinent rats was decreased by 61.9%. No change in Bmax value was observed in other brain regions and spinal cord. The Kd values were unaffected. Subcutaneous administration of DPAT produced hypothermia in rats from which pellets had been removed. The intensity of DPAT-induced hypothermic response was greater in morphine abstinent rats as compared to placebo abstinent rats. Since DPAT is believed to have a major action on the presynaptic 5-HT neurons, it is concluded that in morphine abstinent rats 5-HT1A receptors are down-regulated in hypothalamus, but in morphine tolerant-dependent rats they are unaffected.  相似文献   
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Background: Many studies have addressed the effect of the timing of surgery for breast cancer relative to menstrual cycle phase, with conflicting results. Explanations for the possibility that survival could be altered by the appropriate timing of breast cancer surgery in humans remain speculative. Methods: We examined the expression of three estrogen related proteins (c-erbB-2, cathepsin D, pS2) in the breast tumors from 69 premenopausal women sampled in different phases of the menstrual cycle. Data on S-phase fraction and hormone receptor expression were also analyzed. Immunohistochemical assays were used to measure the proteins of interest. S-phase fraction was determined by flow cytometry. Analyses were performed based on fraction of cells staining positive for the protein, density of stain, and a histoscore that combined both fraction of positive cells and density. Results: We found no differences in c-erbB-2, cathepsin D, hormone receptor, or S-phase levels in tumors sampled in the follicular versus luteal phase, or perimenstrual versus periovulatory phase. The exception was pS2, which was expressed at greater levels during the luteal than during the follicular phase of the cycle (p<0.01); but there was no difference in pS2 expression when the patients were classified as periovulatory versus perimenstrual. Conclusions: Our findings do not support a variation in c-erbB-2, cathepsin D, S-phase fraction, or receptor expression as an explanation for the differences in breast cancer prognosis when surgery is timed by menstrual cycle phase. The finding that pS2 (an indicator of hormone sensitivity, and possibly better prognosis) is expressed at higher levels in tumor samples during the luteal phase suggests that the biologic profile of breast tumors may vary with the menstrual cycle and that these variations deserve further study.  相似文献   
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A 32-year-old male presented with progressive weakness and numbness of both upper limbs of one-month duration. The patient had weakness and wasting of small muscles of both hands with weak grip. Sensory system revealed graded sensory loss to pain, temperature and touch in C5 to T1 distribution and vibration and joint position sense from C5 to C8 in the both upper limbs. There was areflexia in the upper limbs while there was no motor or sensory deficit in the lower limbs. The cortical potential on stimulation of posterior tibial nerve was prolonged on both sides. On MR imaging of the cervical spine there was iso to low intense lesion which was hyperintense on T2-weighted imaging along the dorsal aspect of the cord extending from C2 to C6 level. The axial images showed involvement of the posterior column. The serum vitamin B12 level was found to be low. The patient responded to parenteral cyanocobalamine therapy and the radiological lesion subsequently resolved.  相似文献   
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Xanthotoxol (XT), 8-hydroxypsoralen, exhibited dose-graded sedative activity in dogs, cats, rats, mice and hamsters. At doses of 5-20 mg/kg intraperitoneally (i.p.) in cats and 3-100 mg/kg orally (p.o.) in dogs, XT blocked predatory mouse/rat killing behavior. In mice, XT (10-300 mg/kg i.p.) exhibited a dose-dependent reduction in locomotor activity but was less potent in this regard than reference diazepam (10-100 mg/kg i.p.). XT in mice (0.1-10.0 mg/kg i.p.) and in hamsters (0.1-10.0 mg/kg p.o.) antagonized amphetamine-induced hypermobility but was less potent than diazepam. XT elevated the electrical threshold in foot-shock-induced fighting behavior in rats. XT (0.1-30.0 mg/kg p.o.) potentiated pentobarbital-induced narcosis in hamsters at otherwise subeffective doses of pentobarbital. Conditioned avoidance responses in rats were not significantly altered with 1-3 mg/kg i.p. and 30-100 mg/kg p.o. doses of XT but 300 mg/kg p.o. blocked both conditioned and unconditioned response. Doses of 100-1000 mg/kg i.p. of XT in mice were used to study 48-h acute toxicity of XT and its LD50 was estimated to be 468 mg/kg. Doses of 10, 40 and 80 mg/kg p.o. were used to study the chronic toxicity of XT in rats for 6 months and no side effects or abnormalities in reproductive activity or endocrine integrity were noted. The F1 generation of rats from 6-month XT-treated parents were free of teratogenic effects.  相似文献   
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