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81.
BackgroundThe sphenoid sinus is considered as the most variable pneumatized structure of the skull.PurposeThe aim of the present study was to determine the prevalence of the Onodi cell as well as to evaluate the relationship between the sphenoid sinus type of pneumatization and the presence of surrounding neurovascular protrusion using cone beam computed tomography (CBCT).MethodsThe CBCT images of 500 patients/996 sides [203 males (40.6%) and 297 females (59.4%)] were analyzed in this study. The type of sphenoid sinus pneumatization, prevalence of internal carotid artery (ICA) and optic nerve (ON) protrusion and dehiscence, and also the frequency of Onodi cell were assessed.ResultsThe percentages of the conchal, presellar, sellar, postsellar (a), and postsellar (b) types of pneumatization were 1%, 11.5%, 35.5%, 38.9%, and 13.1%, respectively. The more the sphenoid sinuses pneumatized, the greater the frequency of ON and ICA protrusion and dehiscence of their wall to the sinus. The prevalence of Onodi cell was 38.8%. A significant correlation was found between ON dehiscence and the presence of Onodi cells.ConclusionThe present study demonstrated a significant relationship between the sinus type and frequency of neurovascular protrusions. Therefore, the sphenoid sinus extent of pneumatization might be useful in predicting the risk of iatrogenic damage to the surrounding structures.  相似文献   
82.
Tyrosine kinases orchestrate key cellular signaling pathways and their dysregulation is often associated with cellular transformation. Several recent cases in which inhibitors of tyrosine kinases have been successfully used as anticancer agents have underscored the importance of this class of proteins in the development of targeted cancer therapies. We have carried out a large‐scale loss‐of‐function analysis of the human tyrosine kinases using RNA interference to identify novel survival factors for breast cancer cells. In addition to kinases with known roles in breast and other cancers, we identified several kinases that were previously unknown to be required for breast cancer cell survival. The most surprising of these was the cytosolic, nonreceptor tyrosine kinase, Bruton's tyrosine kinase (BTK), which has been extensively studied in B cell development. Down regulation of this protein with RNAi or inhibition with pharmacological inhibitors causes apoptosis; overexpression inhibits apoptosis induced by Doxorubicin in breast cancer cells. Our results surprisingly show that BTK is expressed in several breast cancer cell lines and tumors. The predominant form of BTK found in tumor cells is transcribed from an alternative promoter and results in a protein with an amino‐terminal extension. This alternate form of BTK is expressed at significantly higher levels in tumorigenic breast cells than in normal breast cells. Since this protein is a survival factor for these cells, it represents both a potential marker and novel therapeutic target for breast cancer. © 2013 Wiley Periodicals, Inc.  相似文献   
83.

Purpose

To analyze the relationship between oxygen desaturation episodes during a laboratory-based ADL protocol and in real-life routine in patients with stable chronic obstructive pulmonary disease (COPD).

Methods

Twenty patients with stable COPD (12 men, 70 ± 7 years, FEV1% 54 ± 15 predicted) with no indication for long-term oxygen therapy (LTOT) were submitted to assessments including ADL performance by the Londrina ADL Protocol (LAP) and level of physical activity in daily life, both while submitted to simultaneous activity and pulse oximeter monitoring.

Results

Episodes of desaturation ≥ 4% (ED ≥ 4%) during the LAP were correlated both with ED ≥ 4% in daily life (r = 0.45) and number of episodes of SpO2 under 88% (ED < 88%) in daily life (r = 0.59). ED < 88% during the LAP was also correlated with ED < 88% in daily life (r = 0.51), explaining 43% of its variance.

Conclusion

In stable patients with COPD and no indication of LTOT, episodes of desaturation during a lab-based ADL protocol are moderately related to episodes of desaturation in daily (real) life, especially those episodes under 88%.
  相似文献   
84.
Consensus-derived structural determinants of the ankyrin repeat motif   总被引:13,自引:0,他引:13       下载免费PDF全文
The ankyrin repeat is one of the most common, modular, protein-protein interaction motifs in nature. To understand the structural determinants of this family of proteins and extract the consensus information that defines the architecture of this motif, we have designed a series of idealized ankyrin repeat proteins containing one, two, three, or four repeats by using statistical analysis of approximately 4,000 ankyrin repeat sequences from the PFAM database. Biophysical and x-ray crystallographic studies of the three and four repeat constructs (3ANK and 4ANK) to 1.26 and 1.5 A resolution, respectively, demonstrate that these proteins are well-folded, monomeric, display high thermostability, and adopt a very regular, tightly packed ankyrin repeat fold. Mapping the degree of amino acid conservation at each position on the 4ANK structure shows that most nonconserved residues are clustered on the surface of the molecule that has been designated as the binding site in naturally occurring ankyrin repeat proteins. Thus, the consensus amino acid sequence contains all information required to define the ankyrin repeat fold. Our results suggest that statistical analysis and the consensus sequence approach can be used as an effective method to design proteins with complex topologies. These generic ankyrin repeat proteins can serve as prototypes for dissecting the rules of molecular recognition mediated by ankyrin repeats and for engineering proteins with novel biological functions.  相似文献   
85.
86.
Trauma und Berufskrankheit - Frakturen der Mittelhandknochen verlaufen nicht selten komplikationsbehaftet und zeigen einen durch Delayed Union oder Pseudarthrosenbildung verzögerten...  相似文献   
87.

Background

Septic arthritis of the costovertebral thoracic joint is a rare site infection. We report an isolated case of septic arthritis of the 10th costo-vertebral right joint with osteitis due to Staphylococcus aureus.

Case presentation

A 59 year old Tunisian man presented with a 2 months history of dorsal spinal pain with fever, associated with asthenia, anorexia and loss of weight. There was a raised C-reactive protein (176 mg/L) and erythrocyte sedimentation rate (100 mm/1st h). Tests for tuberculosis and brucellosis were negative. In the present patient, the clinical symptoms were unspecific with lack of obvious predisposing factors. He had neither history of taking immunosuppressors nor of any disease indicative of immunodeficiency. Thoraco-abdominal computed tomography (CT) showed a lytic lesion centered on the 10th costo-vertebral right joint and histo-pathologic exam of the costo-vertebral puncture confirmed chronic active osteitis and bacteriologic culture allowed identifying methicillin-sensitive Staphylococcus aureus. The patient was treated with ciprofloxacin 1500 mg/day, associated with daily rifampin (20 mg/kg) for total treatment duration of 12 weeks after consulting infectious disease specialists. After a follow-up of 6 months, the patient remained asymptomatic and the markers of inflammation negative.

Conclusion

Septic arthritis of costovertebral joints should be considered when a patient presents with back pain, fever and elevated inflammatory markers. The diagnosis of septic arthritis of costovertebral joints remain a challenge to clinicians. CT is important to confirm a diagnosis and guide costovertebral biopsy and culture. Early and appropriate antibiotic therapy is important for a required outcome.  相似文献   
88.
We have previously shown that the serum aminoterminal propeptide of type III procollagen (PIIINP) is a prognostic factor for survival in localised soft-tissue sarcomas, and that elevated values are frequent in metastatic discase. In the present study PIIINP is analysed during chemotherapy in 26 patients with advanced sarcomas. Non-responders had a significantly higher pretreatment level of PIIINP than responders (P=0.05), when only patients with no recent therapeutic interventions were studied. However, during chemotherapy PIIINP followed the clinical course of the malignant disease in only a minority of patients. Patients with recent surgery or recently completed chemotherapy had an increased pretreatment PIIINP value (P=0.03). In these patients PIIINP declined during chemotherapy irrespective of tumour response. A pretreatment PIIINP level within the reference range tended to increase with time irrespective of response. Moreover, the values taken during a chemotherapy infusion were significantly higher than those immediately preceding the corresponding cycle (P=0.001). Our results suggest that pretreatment PIIINP is of value as a prognostic factor for chemotherapy response in patients with advanced sarcomas. During chemotherapy PIINP is of minor importance in monitoring response because of the influence of chemotherapy and other therapeutic interventions on the level of PIIINP.This study was supported in part by grants from the Finnish Cancer Foundations, the Medical Research Council of the Academy of Finland and Finska Läkaresällskapet (Finnish Medical Society)  相似文献   
89.
In the CAPRISA 004 trial, adherence was estimated as the proportion of reported sex acts covered by two gel doses, which was assessed by counting returned empty gel applicators. The returned empty applicators were inspected visually in a standardized manner for residue on the outside of the applicator, as an indicator of vaginal insertion. Over 15 months, spanning 11,839 study visits by 838 women, a total of 59,800 returned empty applicators were inspected. By visual assessment, 77.5 % of these applicators appeared to have been inserted. To test the accuracy of the assessment we fitted a Cox model and found that the risk for HIV infection was doubled when less than half of the returned empty applicators had been assessed as not inserted in the vagina. Visual inspection enhanced both the accuracy of the adherence measurement and aided identification of mechanical problems with applicator use experienced by women in the trial.  相似文献   
90.
Young women in sub-Saharan Africa are disproportionately affected by HIV, making the development of women initiated and controlled methods of prevention, including microbicides, a priority. Adherence is pivotal to microbicide efficacy and partner related factors are known to impact adherence. An analysis of disclosure of gel use to sexual partners and adherence in CAPRISA 004 women was conducted to better understand this relationship. Partner disclosure was significantly associated with a modest 4.2 % increased adherence (71.0 vs. 66.8 %, p = 0.03). Most women rated the experience of disclosure as positive, despite 6.7 % of partners expressing a negative reaction.Participants who disclosed were more likely to reside with their regular partner (14.4 vs. 8.4 %; p = 0.01) and reported consistent condom use at baseline (32.9 vs. 20.9 %; p < 0.01). Partner disclosure needs to be better understood as a potential facilitator or barrier to microbicide adherence.  相似文献   
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