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51.
Ischemia-reperfusion injury in the kidney is known to cause induction of the inducible form of the 70 kDa heat shock protein HSP70i (or HSP72). However, knowledge of the expressional regulation of the two coding genes for HSP70i –HSP70-1 gene and HSP70-2 gene – is very limited. We investigated the time course of HSP70-1 and -2 mRNA expression and its relation to cellular ATP levels in the renal cortex after different periods of unilateral warm renal ischemia (10–60 min) and reperfusion (up to 60 min) in 10-week-old male Wistar rats. Immediately after ischemia there was a significant induction of both HSP70i genes. While HSP70-1 expression constantly increased (up to 4-fold) during reperfusion, even to a higher extent with prolongation of ischemia, HSP70-2 mRNA – which was generally expressed at a far lower level than HSP70-1 mRNA – was strongly induced (3-fold) during reperfusion only after brief periods (10 min) of ischemia. Cellular ATP levels rapidly dropped to 5% with ischemia and the pattern of recovery during reperfusion significantly depended on the duration of the ischemic period, thus showing a good relation with the heat shock (protein) gene expression. We conclude that HSP70-2 is the more sensitive gene with a lower activation threshold by mild injury, while the HSP70-1 gene mediates the major response of heat shock protein induction after severe injury. Received: 16 November 1998 / Accepted: 11 March 1999  相似文献   
52.
The efficacy and tolerance of 20 mg flunarizine i.v. were tested in comparison with placebo in a multicentre randomised double-blind trial in the acute treatment of migraine attacks. Sixty case reports were included in the evaluation; 31 patients were treated with flunarizine and 29 with placebo. Flunarizine proved to be significantly superior in its effect on the intensity of pain and the typical concomitant symptoms of the attacks. Patients were classed as responders who displayed a reduction in pain intensity by at least 50% within 60 minutes after the administration of flunarizine. 23 patients (= 74.2%) were responders, including 11 patients being without pain after 60 minutes. In the placebo group the responder rate was 27.6% The fact that both groups were comparable in all respects should be emphasized. The tolerance of intravenously administered flunarizine was excellent and corresponded to that of placebo. Apart from a sedative effect reported by 9 patients there were no side-effects. The circulatory conditions remained largely stable. The result of this study seems to indicate that an intravenous injection of 20 mg flunarizine might represent a genuine alternative, and as regards tolerance even a superior one, to the parenteral administration of ergotamine in migraine attacks.  相似文献   
53.
OBJECTIVES: Macrolide-lincosamide-streptogramin B (MLSB) resistance determinants of group A streptococci (GAS) in Ankara, Turkey, were defined for the first time. ISOLATES AND METHODS: A total of 1355 GAS isolates, collected from three different regions of Ankara, were screened for erythromycin resistance. Resistance phenotypes were determined by a triple-disc test, and the gene determinants responsible were determined by PCR. MICs of erythromycin, clindamycin and spiramycin were measured for the resistant isolates, and susceptibility rates to some further antibiotics were determined. RESULTS: Thirty-six isolates (2.6%) were resistant to erythromycin. Of these, 17 (47.2%) expressed macrolide-restricted resistance (M phenotype), while the remainder expressed inducible (16 isolates, 44.4%) or constitutive (three isolates, 8.3%) MLSB resistance. All isolates of the M phenotype harboured the mef(A) gene. Of non-M isolates, 14 harboured erm(A) subclass erm(TR) and five had erm(B) genes. There was a significant relationship between tetracycline resistance and the inducible phenotype (P < 0.05). Macrolide resistance was significantly higher in adults (P < 0.05), and increased more than two-fold in 2002 compared with 2001 (P < 0.05). CONCLUSION: The prevalence of macrolide resistance in GAS is low in Ankara; therefore, routine antimicrobial susceptibility testing against these agents seems unwarranted.  相似文献   
54.
Fiberoptic bronchoscopy (FOB) via endotracheal tube (ETT) is the most frequent utilized technique for monitoring of percutaneous dilatational tracheostomy (PDT) procedure while maintaining mechanical ventilation. Endoscopic guidance has increased the safety of this procedure; nevertheless, the use of a bronchoscope via ETT potentially may deteriorate ventilation and lead to hypercarbia and/or hypoxia. EtView tracheoscopic ventilation tube (EtView TVT) is a standard endotracheal tube with a camera and light source embedded at the tip. The objectives of this study are to introduce EtView TVT as a monitoring tool during PDT and to compare it with video assisted FOB via ETT. We hypothesized that using EtView TVT during PDT may obtain similar visualization; also may have advantages regarding better mechanical ventilation conditions when compared with video-assisted FOB via ETT. Patients, 18–75 years of age requiring mechanical ventilation scheduled for PDT were randomly allocated into two groups for airway monitorization to guide PDT procedure either with FOB via ETT (Group FOB, n = 12) or EtView TVT (Group EtView, n = 12). After standard anesthesia protocol, alveolar recruitment maneuver was applied and all patients were mechanically ventilated at pressure-controlled ventilation mode with same pressure levels. The primary outcome variable was the reduction in arterial oxygen partial pressure (PaO2) values during the procedure. Other respiratory variables and the effectiveness (the visualization and identification of relevant airway structures) of two techniques were the secondary outcome variables. Patients in both groups were comparable with respect to demographic characteristics and initial respiratory variables. Visualization and identification of relevant airway structures in any steps of the PDT procedure were also comparable. The decrease in minute ventilation in Group FOB was higher when compared with Group EtView (51 ± 4 % vs. 12 ± 7.3 %, p < 0.05). The decrease in PaO2 from initial levels during (34 ± 21 % vs. 5 ± 7 % decrease) and after (26 ± 27 % vs. 2.8 ± 16 % decrease) the procedure was higher in Group FOB when compared with Group EtView (p < 0.05). Considering comparable features in monitorization and advantageous features over mechanical ventilation when compared with video bronchoscopy; EtView TVT would be a good alternative for airway monitorization during PDT especially for patients with poor pulmonary reserve.  相似文献   
55.
Vogt-Koyanagi-Harada (VKH) disease is a rare inflammatory ocular disorder that is characterized by bilateral granulomatous panuveitis, neuropathy, and aseptic meningitis, along with various extraocular manifestations. VKH disease has been reported to be associated with various immune disorders. In this report, a case of VKH disease is presented that is associated with mesenteric vascular disease and intestinal necrosis, with an emphasis on the fact that this is the first case documented in the literature of both diseases occurring simultaneously.  相似文献   
56.
Good quality three-view radiographs (anteroposterior, lateral, and open-mouth/odontoid) of the cervical spine exclude most unstable injuries, with sensitivity as high as 92% in adults and 94% in children. The diagnostic performance of helical computed tomography (CT) scanners may be even greater, with reported sensitivity as high as 99% and specificity 93%. Missed injuries are usually ligamentous, and may only be detected with magnetic resonance imaging (MRI) or dynamic plain radiographs. With improvements in the accessibility of advanced imaging (helical CT and MRI) and with improvements in the resolution of such imaging, dynamic screening is now used less commonly to screen for unstable injuries. This case involves a patient with an unstable cervical spine injury whose cervical subluxation was only detected following use of dynamic radiographs, despite a prior investigation with helical CT. In this way, the use of dynamic radiographs following blunt cervical trauma should be considered an effective tool for managing acute cervical spine injury in the awake, alert, and neurologically intact patient with neck pain.  相似文献   
57.
58.

Context

In the last few years, the treatment of renal cell carcinoma (RCC) has progressed significantly, and some histopathologic issues have become important for selection and follow-up after medical and surgical therapies.

Objective

The aim of this collaborative article is to review the most recent literature on the role of traditional histopathologic features obtained from renal core biopsy or nephrectomy specimens in the management of confined, locally advanced, and metastatic RCC.

Evidence acquisition

A nonsystematic review of the literature was performed in April 2010 using the Medline database. Multiple free-text searches were performed for the following items: renal cell carcinoma, clear cell, papillary, chromophobe, histologic* subtype*, histotype*, nuclear grade*, necrosis, sarcomatoid differentiation, biopsy, molecular marker*, and cytogenetic marker*. A total of 2369 records were retrieved from Medline, and 263 full-text studies were considered and partially included in the present review. A panel of experts reached consensus on the main subheadings of this paper.

Evidence synthesis

Core needle biopsies can provide important information that is useful to avoid the overtreatment of benign tumors and to help plan watchful waiting or minimally invasive treatments in selected patients. Tumor histotype is fundamental in the pathologic report. In the context of integrated prognostic systems, the combination of the most important clinical and pathologic factors (TNM stage, Fuhrman nuclear grade, presence of necrosis, microvascular invasion, and sarcomatoid dedifferentiation) allows us to reach a high prognostic accuracy. These models can be used to select patients suitable for adjuvant protocols, to design an appropriate follow-up schedule, and to provide careful patient counseling. Molecular and cytogenetic markers should be further evaluated.

Conclusions

The histopathologic definition of parenchymal epithelial renal tumors is fundamental to plan the management and follow-up of patients with locally confined, locally advanced, and metastatic RCC.  相似文献   
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