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排序方式: 共有765条查询结果,搜索用时 15 毫秒
31.
Nematzadeh S Shoeib N Shahcheraghi F Fereshteh S Feizabadi MM Mehdi FM Nikbin VS Sadat NV Nasehi L Leila N 《Indian journal of medical microbiology》2011,29(3):254-257
Purpose: Plasmid-encoded CTX-M-group of extended-spectrum β-lactamases (ESBLs) represent a significant and rapidly emerging problem in most part of the world. The aim of the present study was to describe the prevalence of CTX-M producing Klebsiella pneumoniae at Tehran hospitals. Materials and Methods: Clinical isolates of K. pneumoniae (n=250) were collected from 10 hospitals of Tehran. Susceptibility to antimicrobial agents, MIC of cefotaxime and ESBLs production of collected isolates were detected. All ESBL-producing isolates were screened for blaCTX-M genes using PCR and DNA sequencing. Molecular typing of blaCTX-M harboring isolates was performed by Pulsed–field gel electrophoresis assay. Results: Of 250 K. pneumoniae clinical isolates, 102 isolates revealed ESBLs – phenotype. PCR assay and sequencing detected blaCTX-M genes in 71.5% (n= 73) of ESBL-producing isolates. The prevalence of CTX-M -I and CTX-M-III clusters among these isolates was 35.61% (n=26) and 21.9 % (n=16) respectively. Coexistence of CTX-M -I and CTX-M-III clusters was found among 42.5% (n= 31) of isolates. Of 102 isolates that were positive in the phenotypic confirmatory test (PCT), 29 isolates (28.4%) did not produce any amplicons in PCR for blaCTX-M gene. The results of PCR for CTX-M -II and CTX-M-IV clusters were also negative. Analysis of the 31 CTX-M producing K. pneumoniae isolates by PFGE typing showed 26 distinct patterns. Conclusions: The blaCTX-M genes are widespread among Iranian isolates of K. pneumoniae. PFGE demonstrated the high diversity of K. pneumoniae harboring blaCTX-M in our study. 相似文献
32.
Liping Zhang Emily C. Cherney Xiao Zhu Tai-an Lin Johnni Gullo-Brown Derrick Maley Kathy Johnston-Allegretto Lisa Kopcho Mark Fereshteh Christine Huang Xin Li Sarah C. Traeger Gopal Dhar Aravind Anandam Sandeep Mahankali Shweta Padmanabhan Prabhakar Rajanna Venkata Murali Thanga Mariappan Robert Borzilleri Gregory Vite John T. Hunt Aaron Balog 《ACS medicinal chemistry letters》2021,12(3):494
Indoleamine 2,3-dioxygenase 1 (IDO1) has been identified as a target for small-molecule immunotherapy for the treatment of a variety of cancers including renal cell carcinoma and metastatic melanoma. This work focuses on the identification of IDO1 inhibitors containing replacements or isosteres for the amide found in BMS-986205, an amide-containing, IDO1-selective inhibitor currently in phase III clinical trials. Detailed subsequently are efforts to identify a structurally differentiated IDO1 inhibitor via the pursuit of a variety of heterocyclic isosteres, leading to the discovery of highly potent, imidazopyridine-containing IDO1 inhibitors. 相似文献
33.
Esmaeili Mahani S Motamedi F Javan M Ahmadiani A 《Pharmacology, biochemistry, and behavior》2005,81(1):152-157
It has been shown that nifedipine, as a calcium channel blocker, can attenuate the development of tolerance to the antinociceptive effect of morphine; however, the role of HPA axis on this action has not been elucidated. We examined the effect of nifedipine on morphine analgesic tolerance in intact and adrenalectomized (ADX) rats and on HPA activity induced by morphine. Adult male rats were rendered tolerant to morphine by daily injection of morphine (15 mg/kg i.p.) for 8 days. To determine the effect of nifedipine on the development of morphine tolerance, nifedipine (1, 2 and 5 mg/kg i.p.) was injected concomitant with morphine. The tail-flick test was used to assess the nociceptive threshold, before and 30 min after morphine administration in days 1, 3, 5 and 8. Our results showed that despite the demonstration of tolerance in both ADX and sham operated rats, nifedipine in ADX rats prevented morphine tolerance development at a lower dose (2 mg/kg) than in sham operated rats, however corticosterone replacement prevented nifedipine effect in ADX rats. Acute administration of morphine produced significant increase in plasma corticosterone level, and with repeated injection, a tolerance to this neurosecretory effect was developed. Nifedipine (5 mg/kg) attenuated the acute effect of morphine, but could not block its neurosecretory tolerance. 相似文献
34.
Masoomeh Barzegari Haiedeh Ghaninezhad Parisa Mansoori Arash Taheri Zahra S Naraghi Masood Asgari 《BMC dermatology》2005,5(1):1-4
Background
Recently, it has been observed that Video Display Terminals (VDTs) usage for long periods can cause some dermatological manifestations on the face. An analytical cross-sectional study was designed in order to determine this relationship.Methods
In this study, 600 office workers were chosen randomly from an organization in Tehran (Iran). The subjects were then divided into two groups based on their exposure to VDTs. 306 workers were considered exposure negative (non VDT user) who worked less than 7 hours a week with VDTs. The remainders 294 were exposure-positive, who worked 7 hours or more with VDTs. The frequency of dermatologic manifestations was compared in these two groups.Results
In the exposure-positive and exposure-negative groups, the frequency of these dermatologic manifestations were 27 and 5 respectively. After statistical analysis, a P.value of < 0.05 was obtained indicating a statistically significant difference between these two groups for dermatological manifestations.Conclusion
According to our study, there is a relationship between dermatologic manifestations on the face and exposure to VDTs. 相似文献35.
OBJECT: The aim of this study was to analyze a subgroup of patients harboring cerebellopontine angle meningiomas originating from the posterior petrous bone in regard to clinical presentation, surgical anatomy, complications, and long-term functional postoperative results. METHODS: Data in a series of 51 patients with meningiomas of the posterior petrous bone who had undergone microsurgical treatment at the authors' institution between 1989 and 2002 were retrospectively reviewed. The patient population consisted of 46 women and five men with a mean age of 53 years (range 22-70 years). The main symptom on first admission was impaired hearing in 41%, dizziness in 20%, and tinnitus in 18% of the patients. Results of physical examination and audiological testing revealed hypacusis in 65% of patients, cerebellar ataxia in 31%, and impairment of the fifth cranial nerve in 26%. All patients underwent surgical treatment via a lateral suboccipital approach. Intraoperatively, the tumor was found to be attached to the postmeatal dura in 37%, the premeatal dura in 27.5%, the suprameatal dura in 19.6%, the inframeatal dura in 7.8%, and centered on the porus acusticus in 5.9% of cases. Tumor extension into the internal acoustic meatus was present in seven patients. Tumor resection was categorized as Grade I in 14 patients, Grade II in 29, Grade III in six, and Grade IV in two patients, according to the Simpson classification system. The site of displacement of the cranial nerves was predictable in up to 84% of patients, depending on the dural origin of the tumor as depicted on preoperative magnetic resonance (MR) imaging studies. Postoperatively, a new and permanent facial paresis was observed in five patients (9.8%). In 38 patients in whom both pre- and postoperative audiological data were available, hearing function deteriorated after surgery in 18.4% and improved in 7.9%. Clinical and MR imaging postsurgical data from a mean period of 5.8 years (range 13 months-13 years) were available in all patients. Forty-four patients (86%) resumed normal daily activity. Tumor recurrence was observed in two patients (3.9%), and both underwent a second surgery. CONCLUSIONS: Preoperative detailed analysis of MR imaging data gives the surgeon a clue about the dislocation of critical neurovascular structures, particularly the cranial nerves. Nonetheless, the exact relationship of the cranial nerves to the tumor (dislocation, adherence, infiltration, and splaying of nerves) can only be fully appreciated during surgery. 相似文献
36.
37.
Intra-operative characterization of gliomas by near-infrared spectroscopy: possible association with prognosis 总被引:2,自引:0,他引:2
Summary ?Background. Growth and expansion of gliomas are highly dependent on vascular neogenesis. An association of microvascular density and
tumour energy metabolism is assumed in most human gliomas. The purpose of this investigation was to characterize a series
of gliomas by intra-operative near-infrared spectroscopy (NIRS), and to elucidate the relationship between microvascular blood
volume (BV), oxygen saturation (SaO2), histology and patient survival.
Method. The study included 13 patients with gliomas, in whom complete tumour resection according to postoperative magnetic resonance
imaging criteria was achieved. Intra-operatively, one low grade astrocytoma, five anaplastic astrocytomas and seven glioblastomas
with the ipsilateral cortex were investigated by NIRS revealing capillary BV (total haemoglobin) and SaO2. Intratumoural BV (tBV) and SaO2 (tSaO2) were additionally used in relation to histology and survival.
Findings. The mean tBV of the astrocytomas was 4.96 mg/ml compared to 18.40 mg/ml in the glioblastoma group. Mean tSaO2 was 36% in the astrocytoma group and 52% in the glioblastomas, respectively. Both tBV and tSaO2 were significantly higher (p<0.01) in the glioblastoma group. Median survival time was shortest for patients with glioblastoma
(12.5 months), with tBV >10/mg/ml (10 months), and tSaO2 >50% (10 months). Longest median survival times were observed in the astrocytoma group (32.5 months), in patients with Tbv
<10/mg/ml (30 months), and tSaO2 <50% (27.5 months). The differences were highly significant (p<0.01).
Interpretation. Intra-operative characterization of gliomas by NIRS is feasible. High tBV represents extensive angiogenetic activity of
the tumour, whereas high tSaO2 may be result of non-oxidative glucose metabolism with less oxygen extraction from the capillary bed of the tumour. However,
the extent of tBV and tSaO2 are both of possible prognostic value thus resulting in additional information about the tumour.
Published online June 11, 2003 相似文献
38.
X Lin K Asgari M J Putzi W R Gage X Yu B S Cornblatt A Kumar S Piantadosi T L DeWeese A M De Marzo W G Nelson 《Cancer research》2001,61(24):8611-8616
39.
40.
Sajad Jeddi Amir Nezami Asl Alireza Asgari Asghar Ghasemi 《Arquivos brasileiros de cardiologia》2016,106(1):41-48