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51.
52.
Laboratory detection of Haemophilus influenzae with decreased susceptibility to nalidixic acid, ciprofloxacin, levofloxacin, and moxifloxacin due to GyrA and ParC mutations 下载免费PDF全文
Pérez-Vázquez M Román F Aracil B Cantón R Campos J 《Journal of clinical microbiology》2004,42(3):1185-1191
The detection of clinical isolates with decreased fluoroquinolone susceptibilities and a resistance mechanism is of epidemiological and clinical interest. We studied the susceptibilities of 62 clinical isolates and 2 American Type Culture Collection reference strains of Haemophilus influenzae to ciprofloxacin, levofloxacin, moxifloxacin, and nalidixic acid by the microdilution and disk diffusion methods. The ciprofloxacin MICs for 34 of the isolates were >/=0.12 micro g/ml (range, 0.12 to 32 micro g/ml), and the ciprofloxacin MICs for 28 matched control isolates were =0.06 micro g/ml. In addition, we sequenced the quinolone resistance-determining regions (QRDRs) of gyrA and parC of all strains. The log(2) MICs of all quinolones were plotted against the inhibition zone diameters. The MICs and inhibition zone diameters selected to screen for the resistance mechanism were based on the susceptibility distribution data and the presence or absence of amino acid changes in the QRDRs of GyrA and ParC. Strains for which ciprofloxacin MICs were =0.06 micro g/ml, levofloxacin and moxifloxacin MICs were =0.03 micro g/ml, and nalidixic acid MICs were =2.0 micro g/ml lacked modifications in the QRDR of GyrA. In contrast, all strains for which ciprofloxacin, levofloxacin, and moxifloxacin MICs were >/=0.5 micro g/ml and the vast majority of those for which nalidixic acid MICs were >/=32 micro g/ml exhibited amino acid changes in GyrA and ParC. Nalidixic acid and the other three fluoroquinolones studied could be used to screen H. influenzae isolates for the detection of decreased susceptibilities to quinolones due to the acquisition of two amino acid changes in the QRDRs of GyrA and ParC (sensitivity, >95%; specificity, >80%). 相似文献
53.
Kurtz R 《Journal of neurophysiology》2004,92(1):458-467
In motion-sensitive visual neurons of the fly, excitatory visual stimulation elicits Ca(2+) accumulation in dendrites and presynaptic arborizations. Following the cessation of motion stimuli, decay time courses of the cytosolic Ca(2+) concentration signals measured with fluorescent dyes were faster in fine arborizations compared with the main branches. When indicators with low Ca(2+) affinity were used, the decay of the Ca(2+) signals appeared slightly faster than with high affinity dyes, but the dependence of decay kinetics on branch size was preserved. The most parsimonious explanation for faster Ca(2+) concentration decline in thin branches compared with thick ones is that the velocity of Ca(2+) clearance is limited by transport mechanisms located in the outer membrane and is thus dependent on the neurite's surface-to-volume ratio. This interpretation was corroborated by UV flash photolysis of caged Ca(2+) to systematically elicit spatially homogeneous step-like Ca(2+) concentration increases of varying amplitude. Clearance of Ca(2+) liberated by this method depended on branch size in the same way as Ca(2+) accumulated during visual stimulation. Furthermore, the decay time courses of Ca(2+) signals were only little affected by the amount of Ca(2+) released by photolysis. Thus Ca(2+) efflux via the outer membrane is likely to be the main reason for the spatial differences in Ca(2+) clearance in visual motion-sensitive neurons of the fly. 相似文献
54.
Farhi J; Homburg R; Ferber A; Orvieto R; Ben Rafael Z 《Human reproduction (Oxford, England)》1997,12(2):241-243
The most important aspect of diminished ovarian reserve is the associated
decline in reproductive potential. Assessment of ovarian reserve is mainly
based on measurement of early follicular phase follicle stimulating hormone
(FSH) concentration. The objective of this study was to report the
identification of a group of 12 infertile women initially diagnosed as
having unexplained or anovulatory infertility, who had a normal baseline
hormonal profile and did not respond to repeated ovarian stimulation with
gonadotrophins. All developed ovarian failure within a relatively short
time span. Non-response to ovarian stimulation was defined by failure to
achieve development of follicles >12 mm and failure to raise oestradiol
concentration >350 pmol/l in two successive cycles of human menopausal
gonadotrophin (HMG) doses of up to five ampoules per day for 5-8 days.
Within a mean of 9 months following the failed attempts of ovarian
stimulation the mean day 3 FSH concentrations rose from 5.4 +/- 2.7 IU/l to
53.5 +/- 19.7 IU/l. In these patients, day 3 FSH concentration failed to
indicate the low ovarian reserve manifested only by lack of clinical
response to treatment with gonadotrophins which was the first sign of
impending ovarian failure. We conclude that women with normal early
follicular phase serum FSH concentrations who do not respond to ovarian
stimulation by HMG are at risk of developing ovarian failure within several
months.
相似文献
55.
Evaluation of the COBAS TaqMan 48 real-time PCR system for quantitation of hepatitis B virus DNA 总被引:5,自引:0,他引:5 下载免费PDF全文
The purpose of this study is to evaluate the usefulness of the new real-time PCR COBAS TaqMan 48 analyzer, comparing it to the existing COBAS AMPLICOR HBV MONITOR based on conventional PCR technology. The study used 104 samples from different patients. No differences were found in the sensitivity of the tests. There was an excellent correlation between the sample with a viral load within the dynamic range of the two tests (r = 0.938). The COBAS TaqMan test has a wider linear range, and this fact enables quantifying of the viral load without diluting the sample. 相似文献
56.
Ospedal KZ Appel MH Fillus Neto J Mangili OC Sanches Veiga S Gremski W 《International journal of experimental pathology》2002,83(6):287-294
Loxoscelism, the term used to describe envenomation with brown spiders, is characterized by a dermonecrotic lesion at the bite site. In the present investigation we submitted albino rabbits to an acute experimental envenomation protocol using Loxosceles intermedia (brown spider) venom, with in order to determine the pathogenesic features of the lesion induced by this spider, which is the cause of several accidents throughout the world. Rabbits received intradermal injections of the venom and were monitored over the first 4 h, and then at 12 h and 1, 2 and 5 days after envenomation. Histological specimens from 3 rabbits per time point were collected from euthanized animals and processed for histological examination by light microscopy. Major findings observed during the first 4 h were oedema, haemorrhage, degeneration of blood vessel walls, plasma exudation, thrombosis, neutrophil accumulation in and around blood vessels with an intensive diapedesis, a diffuse collection of inflammatory cells (polymorphonuclear leucocytes) in the dermis, and subcutaneous muscular oedema. Over the following hours and up to 5 days after envenomation the changes progressed to massive neutrophil infiltration (with no other leucocytes) into the dermis and even into subcutaneous muscle tissue, destruction of blood vessels, thrombosis, haemorrhage, myonecrosis, and coagulative necrosis on the 5th day. 相似文献
57.
Norihiro Morita W.A. Saad L.A.A. Camargo C.R. Silva Neto J. Antunes-Rodrigues M.R. Covian 《Physiology & behavior》1980,24(2):243-249
Rats bearing lesions in the septal area followed by lesions in the subfornical organ were submitted to various thirst-eliciting procedures. The rats with hyperdipsia induced by lesions of the septal area drank more water than either during the control period or after lesion of the subfornical organ under the same thirst-eliciting or angiotensin-liberating stimuli (polyethyleneglycol, isoproterenol, water deprivation and ligation of the inferior vena cava). The overdrinking elicited by lesions in the septal area was blocked after lesion of the subfornical organ. Neither hypovolemia, nor hypotension or water deprivation could elicit increased water intake in animals whose subfornical organ had been destroyed. Animals with lesions in the subfornical organ showed decreased water intake after cellular dehydration. The results obtained suggest that the subfornical organ acts as a more important structure than the septal area in the regulation of water intake elicited by angiotensin, with two opposite effects: a direct one facilitating water intake, and an indirect one inhibiting the septal area. The septal area has an inhibitory effect on the subfornical organ and on water intake. 相似文献
58.
Rafael Lucas Costa de Carvalho Miguel Lia Tedde Jose Ribas Milanese de Campos Niura Noro Hamilton Gustavo Falavigna Guilherme Vanessa Moreira Sousa Vitor Floriano Salomao Junior Flavio Henrique Savazzi Paulo Manuel Pego-Fernandes 《Journal of pediatric surgery》2021,56(3):545-549
Background/PurposeThe aim of the study was to evaluate the postoperative quality of life (QoL) of patients who underwent minimally invasive repair of pectus excavatum (MIRPE) with a newly designed bar and bar stabilizers.MethodsWe conducted a prospective randomized study in which patients were operated either with standard perpendicular stabilizers (control group) or with the newly designed oblique stabilizers (intervention group). All patients were evaluated 6 months after the operation with the Pectus Excavatum Evaluation Questionnaire (PEEQ).ResultsThere were 16 patients in the control group and 14 in the intervention group. Mean age was 17 (SD: 3.3, range 14–27) years. There were no demographic differences between groups. Two patients in the control group and one in the intervention group were repaired with two bars instead of one. There was one reoperation in each group. There was a significant difference between the pre- and postoperative scores, in both groups, in the patient body image domain (control group: 9.5 to 3; p < 0.01; intervention group 10 to 3; p < 0.01), as well as in the psychosocial domain (control group: 13.5 to 24, p < 0.01; intervention group: 15 to 24, p < 0.01). With regards to the patients' perception of physical difficulties before and after MIRPE, the difference between pre- and postoperative scores was greater in the intervention group (8 to 12, p < 0.01) than in the control group (10 to 11, p = 0.04). The mean length of stay was 4.5 and 5 days in the intervention group and the control group, respectively.ConclusionOur study showed that patients who underwent MIRPE with the newly designed bars and stabilizers had non-inferior outcomes than patients reported in the literature who underwent MIRPE with standard bars and stabilizers. We found slightly better outcomes in patients in the intervention group compared to the control group, but larger studies will be needed to confirm if those differences are statistically significant.Level of evidenceII 相似文献
59.
Liseana O. Barbosa Jos Osvaldo B. Neto Antnio Augusto L. Teixeira-Júnior Leudivan R. Nogueira Jos de Ribamar R. Calixto Isabela W. Cunha Jaqueline D. Pinho Francisco Srgio M. S. do Nascimento Syomara Pereira da C. Melo Fernando A. Soares Gyl Eanes B. Silva 《Translational andrology and urology》2021,10(4):1803
Pseudoangiosarcomatous squamous cell carcinoma, also called pseudovascular, pseudoangiomatoid or adenoid pseudovascular carcinoma, is an uncommon and highly aggressive variant of squamous cell carcinoma. Histologically, it is characterized by proliferation of atypical keratinocytes with acantholysis and formation of pseudovascular spaces, forming anastomosed channels lined with neoplastic cells that invade the dermis. These cells are positive for cytokeratin and negative for vascular markers such as CD31 and CD34. There are few reports of this variant in the literature. Skin, breast, lung and vulva involvement have been described, but to the best of our knowledge, no cases involving the penis has been described. This study aims to describe the first case of angiosarcomatous squamous cell carcinoma of the penis. The patient presented with a painful lesion in the penis associated with urinary retention. Macroscopic findings exhibited an ulcerative vegetating lesion that involving the entire glans and part of the penile body, as well as infiltration of penile structures and scrotal skin. Microscopy shows atypical proliferation of sarcomatous keratinocyte pattern mimicking vascular spaces. Human papilloma virus (HPV) biomarkers and polymerase chain reaction (PCR) were all negative. Advanced penile squamous cell carcinoma with aggressive lymph node metastasis. This report presents the first case of penile pseudoangiosarcomatous squamous cell carcinoma, as an important differential diagnosis. 相似文献
60.
Chlorhexidine susceptibility and Eagle effect in planktonic cells and biofilm of nosocomial isolates
Marchi Ana Paula Farrel Côrtes Marina Vásconez Noguera Saidy Rossi Flavia Levin Anna Sara Figueiredo Costa Silvia Perdigão Neto Lauro Vieira 《European journal of clinical microbiology & infectious diseases》2023,42(6):787-792
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to evaluate the chlorhexidine gluconate (CHG) susceptibility in both planktonic cells and biofilm of... 相似文献