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41.
42.
Anaplasma phagocytophilum is the agent of human anaplasmosis, the second most common tick-borne illness in the United States. This pathogen, which is closely related to obligate intracellular organisms in the genera Rickettsia, Ehrlichia, and Anaplasma, persists in ticks and mammalian hosts; however, the mechanisms for survival in the arthropod are not known. We now show that A. phagocytophilum induces expression of the Ixodes scapularis salp16 gene in the arthropod salivary glands during vector engorgement. RNA interference-mediated silencing of salp16 gene expression interfered with the survival of A. phagocytophilum that entered ticks fed on A. phagocytophilum-infected mice. A. phagocytophilum migrated normally from A. phagocytophilum-infected mice to the gut of engorging salp16-deficient ticks, but up to 90% of the bacteria that entered the ticks were not able to successfully infect I. scapularis salivary glands. These data demonstrate the specific requirement of a pathogen for a tick salivary protein to persist within the arthropod and provide a paradigm for understanding how Rickettsia-like pathogens are maintained within vectors.  相似文献   
43.
OBJECTIVE: Our objective was to assess the frequency and clinical characteristics of migraine in the patients with CM-1. METHODS: We analyzed migraine in 73 patients with CM-1. Migraine was classified according to the new International Headache Society criteria. We did not include patients who had intracranial, parenchymal, or cervical lesions other than CM-1 on brain and cervical magnetic resonance imaging. RESULTS: Of the 73 patients diagnosed as having CM-1, 11 (15.06%) had migraines; of them, 8 (10.95%) had chronic migraines, 2 (2.73%) had migraines with auras, and 1 (1.36%) had migraines without auras. The patients who had both migraines and CM-1 (group 1) were compared regarding clinical characteristics and demographic features to the control group having chronic migraines. The control group comprised subjects free of CM-1. Onset age of pain was earlier and the frequency of headache days per month, baseline pain intensity, exacerbation of pain intensity, nausea, vomiting, and pain aggravated by physical activity were significantly higher in group 1. CONCLUSIONS: Although we found the frequency of migraine to be similar to that in population-based studies, we detected a threefold increased frequency of chronic migraine in this special population. We believe that CM-1 may be a factor associated with chronic migraine.  相似文献   
44.

Objective

The aim of this research was to assess the relationship between mitral annular calcification (MAC) and whole blood viscosity (WBV).

Subjects and Methods

A total of 184 patients with MAC and 133 patients without MAC were enrolled in the study. The WBV was calculated with a confirmed formulation using the hematocrit and total plasma protein at a low shear rate (LSR) and high shear rate (HSR). Early diastolic mitral annular velocity (Ea) and late diastolic mitral annular velocity (Aa) were measured using pulse Doppler tissue echocardiography. Pearson''s correlation analysis was performed to assess the relationship between WBV and mitral annular motion velocities. The effects of different variables on the occurrence of MAC were assessed in univariate and multivariate logistic regression analysis.

Results

In patients with MAC, WBV values were significantly higher at HSR (18.04 ± 0.84 vs. 17.25 ± 0.96 208 s-1, p < 0.001) and at LSR (78.0 ± 14.2 vs. 61.9 ± 17.1 0.5 s-1, p < 0.001). The WBV at HSR and LSR were significantly correlated with Ea (r = −0.477, p < 0.001; r = −0.385, p < 0.001, respectively) and Aa (r = −0.544, p < 0.001; r = −0.323, p < 0.001, respectively). Multivariate analysis showed that WBV of both shear rates was an independent predictor of MAC. Using the ROC curve, a cut-off value of 70.1 for WBV at LSR had a sensitivity of 83.7% and a specificity of 73.7% (AUC 0.785, p < 0.001) and a WBV cut-off value of 17.5 at HSR had a sensitivity of 79.6% and a specificity of 71.4% (AUC 0.761, p < 0.001) for the prediction of MAC.

Conclusion

Patients with MAC had significantly higher WBV, which independently predicted the presence of MAC. WBV had an inverse correlation with mitral annular motion velocities, indicating that a higher WBV may lead to greater limitation in annular motion and, thus, more calcification.Key Words: Mitral valve calcification, Shear stress, Blood viscosity  相似文献   
45.
46.

Purpose

Adenosine deaminase 2 (ADA2) have been reported to cause vasculitic diseases and immunodeficiency recently. Patients present with stroke episodes and rashes mimicking polyarteritis nodosa (PAN). We report a patient who has been followed up with severe neutropenia and found an unexpectedly revealed novel mutation in CECR1 affecting ADA2.

Methods

We reviewed medical records and clinical history of the patient. No mutations in other known neutropenia genes such as ELA, G6PC3, HAX1, AP3B1, LAMTOR2, VPS13B, VPS45, GFI1, JAGN1, or WAS could be detected. Sanger sequencing was used to confirm the genetic variants in the patient and relatives.

Results

Genetic analysis by exome sequencing revealed a novel mutation in the gene CECR1 (c.G962A; p.G321E) which segregated perfectly in the relatives.

Conclusion

This is the first DADA2 patient presenting with severe neutropenia. We suggest that in patients with unexplained cytopenias combined with immunodeficiency, fevers of unknown origin and high inflammation markers, DADA2 should be considered.
  相似文献   
47.
Stature estimation based on hand length and foot length   总被引:1,自引:0,他引:1  
This study was carried out to estimate the relationship between hand length, foot length and stature using multiple linear regression analyses based on a sample of male and female adult Turks residing in Adana. Measurements of hand length, foot length and stature were taken from 155 adult Turks (80 male, 75 female) aged 17-23 years. The participants were students of the Medical Faculty of Cukurova University. A multiple linear regression model was fitted to the observed data. Stature was taken as the response or dependent variable, hand length and foot length were taken as explanatory variables or regressors. All possible (simple and multiple) linear regression models for each of males, females and both genders together were tested for the best model. The multiple linear regression model for both genders together was found to be the best model with the highest values for the coefficients of determination R2 = 0.861 and R2adjusted = 0.859, and multiple correlation coefficient R = 0.928.  相似文献   
48.
The free radical copolymerization of 2-thienylmethyl 4-vinylbenzyl ether (TMVBE) with 2-oxo-2-(2-thienylmethoxy)ethyl-2-methylacrylate (TMOEM) has been carried out in 1,4-dioxane at 65?°C?±?1 and were analyzed by Fourier transform infrared, 1H NMR, and 13C NMR spectroscopy. 1H NMR analysis was used to determine the molar fractions of TMVBE and TMOEM in the copolymers. The monomer reactivity ratios were calculated according to the general copolymerization equation using Kelen–Tüdõs and Finemann–Ross linearization methods. The reactivity ratios indicated a tendency toward alternation copolymerization. The thermal behaviors of copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. Also, the apparent thermal decomposition activation energies were calculated by the Ozawa and Kissinger methods with a Shimadzu TGA 60 thermogravimetric analysis thermobalance. All the products showed moderate activity against different strains of bacteria and fungi.  相似文献   
49.

Objective

Dens fractures are common cervical injuries in advanced aged patients. The presented study was undertaken to analyze the clinical results and risks of surgically treated patients with dens fractures over 70 years.

Methods

Data of 28 patients (17 female, 11 male) over 70 years treated from September 2004 to October 2009 were recorded. Clinical and radiological parameters were obtained including type of fracture, associated cervical and/or other injuries, comorbidities, symptoms, neurological condition, surgical strategy, postoperative course and complications.

Results

89% were in a good neurological condition before surgery (ASIA E or D). In most cases, surgery was performed at an early stage after trauma (21 patients within 5 days). Ventral screw fixation was the preferred surgical strategy (64%). A slight worsening of neurological functions immediately after operation was only seen in one patient. Five patients died in the early and 2 in the late postoperative course which means a treatment mortality of 25%. Among the surviving patients two had general medical complications.

Conclusion

Type II dens fractures are a common fracture of elderly patients. Our results are good concerning the neurological functions. Surgical and general medical complications were acceptable. However, the study also underlines that mortality rate is high and therefore treatment options should be well-considered in this high risk group.  相似文献   
50.
The aim of the study was to investigate if there is a possible relation between intestinal parasitosis and handedness in patients with suspected intestinal parasitosis. Hand preference was assessed on the Edinburgh Handedness Inventory. Stool samples were examined microscopically for the presence of parasite. In the present study right-handers had many more helminth infections and left-handers had many more protozoon infections. Lower rate of helminth infections in the present study, and higher asthma incidences in the left-handed population in literature, may be associated with different immune machinery in left-handed people than in right-handed ones.  相似文献   
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