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51.
BACKGROUND: Although Helicobacter pylori is a significant etiologic factor of peptic ulcer disease, it remains unknown why ulcers develop only in the minority of infected individuals. AIM: The aim of this cross-sectional study was to evaluate the association between the presence of duodenal ulcer in H. pylori-infected patients and different risk factors. METHODS: A total of 122 H. pylori-infected patients were enrolled; 79 had duodenal ulcer and 43 gastritis. Univariate analysis was conducted using either Fisher's exact test or exact Cochrane-Armitage trend test. In multivariate analysis the logistic model was used. RESULTS: Univariate analysis indicated six factors (male sex, smoking, antral H. pylori density, CAGA presence in antrum, and VACA s1a presence in antrum and corpus). Four factors (sex, smoking-alcohol index, H. pylori density index, and CAGA index) were found to be significant in multivariate analysis. The best model predicting duodenal ulcer included male sex, smoking, presence of H. PYLORI on histopathology in antrum and CAGA presence in corpus. CONCLUSION: Although several risk factors were significantly associated with duodenal ulcer, we failed in the identification of either a single risk factor or a set of factors that can unequivocally differentiate patients with ulcer from those with gastritis.  相似文献   
52.
Infections caused by the spirochete Borrelia burgdorferi sensu lato may be accompanied by other microorganisms, such as Anaplasma, Ehrlichia and Babesia. These pathogens are transmitted by the ticks and are a risk to humans and animals. Ixodes ricinus ticks collected from recreational areas of Szczecin and northwestern Poland contained DNA of the pathogens mentioned above and cases of double and triple coinfection have been documented. The aim of this paper was to determine if dogs suspect to tick infestation in the area of study are a reservoir for these pathogens and to examine the possibility of coinfection. Canine blood was sampled, part of the material originated from dogs exhibiting symptoms of borreliosis. In an earlier study, the samples were screened for DNA from B. burgdorferi sensu lato. In order to screen for A. phagocytophila and Babesia sp. DNA, a PCR-based method was used with the following primers: EHR521/EHR747 for Anaplasma and FOR1/REV1 for Babesia. In 192 samples only two contained A. phagocytophila DNA. One of these samples originated from a healthy canine, the other from an individual with symptoms of borreliosis. The examined samples were not positive for Babesia sp. DNA. Coinfection was not discovered. The low level of A. phagocytophila infection may indicate that the domestic dog is not a reservoir for Anaplasma and Babesia in Szczecin and northwestern Poland. Moreover, this area does not have populations of the brown dog tick (Rhipicephalus sanguineus) or Dermacentor reticulates--both of which are vectors of E. canis and B. canis and commonly induce ehrlichiosis and babesiosis in canines.  相似文献   
53.
Acute coronary syndromes (ACS) without persistent ST-segment elevation are the main cause of hospitalization, morbidity and mortality. The objective of this study was to compare clinical and angiographic parameters as well as in-hospital results of treating 307 consecutive patients with ACS without persistent ST-segment elevation with either PCI or CABG. Inclusion criteria were: rest angina within the last 24 hours, ST-segment depression (> 0.5 mm), T-wave inversion (> 1 mm) in at least two leads, positive serum cardiac markers. PCI was performed in 75.9% of patients and 24.1% of patients underwent CABG. Both groups did not differ as to age, sex, history of diabetes, arterial hypertension, heart failure, smoking and ejection fraction. Positive troponin was significantly more frequent in the PCI group. 51% of PCI patients and 80% of CABG patients had complete revascularization (p = 0.00001). Independent predictors of in-hospital death in the CABG group were: inability to determine culprit vessel during coronary angiography due to lesions' severity (OR 13.65; 95% CI 9.40-15.20; p = 0.007) and heart failure (OR 15.58; 95% CI 12.29-18.01; p = 0.003). In the PCI group these independent predictors were: Braunwald's IIIC unstable angina (OR 5.48; 95% CI 3.10-7.17; p = 0.04) and diabetes (OR 2.22; 95% CI 1.07-3.90; p = 0.003). In-hospital mortality rate was significantly higher in the CABG group (8.1% vs 1.7% p < 0.01). Patients with multivessel coronary artery disease and ACS without ST-segment elevation treated with PCI have better in-hospital outcome than patients assigned to CABG, but the rate of complete revascularization is lower.  相似文献   
54.
Methylammonium lead iodide films and powdered crystals were studied by time-resolved absorption and emission spectroscopy on the time scales from femtoseconds to nanoseconds. Strikingly different transient absorption signals were observed, changing from strong long-wavelength band-edge bleach to weak signatures of band-shift, which depended on the absorber form (films or polycrystals) and preparation method (stoichiometric or non-stoichiometric). The observed differences were correlated with the variation in absorption and emission spectra, changes in photo-induced carrier lifetimes and solar cell efficiency. These differences also pointed out that similar perovskite absorbers can provide significantly different transient responses and emphasize that special care must be taken when interpolating the obtained findings to the processes occurring in the most efficient devices.

Striking differences in transient absorption signal are observed for perovskite absorbers prepared with different methods.  相似文献   
55.
Direct conversion of the α-hydroxyl group by para-toluenesulfonamide to yield α-(N-tosyl)aminophosphonates is reported. α-Aminophosphonates 23a,b–37a,b were obtained from the corresponding α-hydroxyphosphonates 6a,b–21a,b in the presence of K2CO3, via the retro-Abramov reaction of the appropriate aldehydes, 1–5. The subsequent formation of imines with simultaneous addition of diethyl phosphite provided access to the α-sulfonamide phosphonates 23a,b–37a,b with better diastereoselectivity than in the case of the Pudovik reaction. The mechanism for this transformation is proposed herein. When Cbz N-protected aziridine 9a,b and phenylalanine analogue 12a,b were exploited, intramolecular substitution was observed, leading to the corresponding epoxide 38 as the sole product, or oxazolidin-2-one 39 as a minor product. Analogous substitution was not observed in the case of proline 18a,b and serine 21a,b derivatives.

The reaction mechanism and diastereoselectivity of the direct transformation of α-hydroxyphosphonates 6a,b–21a,b by para-toluenesulfonamide, yielding α-(N-tosyl)aminophosphonates 23a,b–37a,b under K2CO3 conditions are presented.  相似文献   
56.

Objective

Quality of care delivered to adult patients in the emergency department (ED) is often associated with demographic and clinical factors such as a patient's race/ethnicity and insurance status. We sought to determine whether the quality of care delivered to children in the ED was associated with a variety of patient‐level factors.

Methods

This was a retrospective, observational cohort study. Pediatric patients (<18 years) who received care between January 2011 and December 2011 at one of 12 EDs participating in the Pediatric Emergency Care Applied Research Network (PECARN) were included. We analyzed demographic factors (including age, sex, and payment source) and clinical factors (including triage, chief complaint, and severity of illness). We measured quality of care using a previously validated implicit review instrument using chart review with a summary score that ranged from 5 to 35. We examined associations between demographic and clinical factors and quality of care using a hierarchical multivariable linear regression model with hospital site as a random effect.

Results

In the multivariable model, among the 620 ED encounters reviewed, we did not find any association between patient age, sex, race/ethnicity, and payment source and the quality of care delivered. However, we did find that some chief complaint categories were significantly associated with lower than average quality of care, including fever (–0.65 points in quality, 95% confidence interval [CI] = –1.24 to –0.06) and upper respiratory symptoms (–0.68 points in quality, 95% CI = –1.30 to –0.07).

Conclusion

We found that quality of ED care delivered to children among a cohort of 12 EDs participating in the PECARN was high and did not differ by patient age, sex, race/ethnicity, and payment source, but did vary by the presenting chief complaint.
  相似文献   
57.
Modification of ultrasmall gold nanoparticles (AuNPs) with the lipoic acid derivative of folic acid was found to enhance their accumulation in the cancer cell, as compared to AuNPs without addressing units. The application of lipoic acid enabled the control of the gold nanoparticle functionalities leading to enhanced solubility and allowing for attachment of both the folic acid and the cytotoxic drug, doxorubicin. More robust attachment of doxorubicin to the nanoparticle through the amide bond resulted in toxicity comparable with that of the drug alone, opening a new perspective for designing more potent, but less toxic nanopharmaceuticals. The increased uptake was accompanied by pronounced nuclear accumulation and observable cytotoxicity. Doxorubicin binding via covalent amide bonds enhanced stability of the whole drug vehicle and provided much better control over doxorubicin release in the cell environment, as compared to physical adsorption or pH sensitive bonding commonly used for anthracycline carriers. Confocal microscopy revealed that the bond was stable in the cytoplasm for 22 h. The ability to slow down the rate of drug release may be crucial for the application in sustained anticancer drug delivery. Biological analyses performed using MTT assay and confocal microscopy confirmed that the ultrasmall AuNPs with the lipoic acid derivative of folic acid exhibit relatively low cytotoxicity, however when loaded with a chemotherapeutic, they cause a significant reduction in the cell viability.

Modification of ultrasmall gold nanoparticles (AuNPs) with the lipoic acid derivative of folic acid was found to enhance their accumulation in the cancer cell, as compared to AuNPs without addressing units.  相似文献   
58.
Purpose

The aim of the study was to assess the effectiveness of Superb Micro-vascular Imaging (SMI) as an alternative to Contrast-Enhanced Ultrasound (CEUS) and Computed Tomography Angiography (CTA) for endoleak detection and classification in patients followed up after endovascular abdominal aortic aneurysm repair (EVAR).

Materials and methods

From May 2015 to January 2017, 30 patients underwent post-EVAR follow-up with Color Doppler Ultrasound (CDUS), CEUS, SMI, and CTA examinations. Aneurysmal sac diameter and graft patency were evaluated; endoleaks were identified and classified. Sensitivity, specificity, and accuracy values were calculated for each of the four diagnostic methods of endoleak detection. A percentage of agreement and Cohen’s Kappa coefficient were calculated for comparison of methods in terms of endoleak identification.

Results

CTA revealed fifteen endoleaks (50%): three type Ia, nine type II, and three type III. The sensitivity of CDUS, CEUS, and SMI relative to CTA was 27%, 100%, and 100%, respectively. Specificity was 93%, 93%, and 93%, respectively. Accuracy was 60%, 97%, and 97%, respectively. There were no differences between SMI and CEUS in terms of sensitivity, specificity, or accuracy (100%, 93%, and 97%). We do not observe statistically significant differences between CTA, CEUS, and SMI concerning endoleak identification ability. The weakest method in endoleak identification was CDUS.

Conclusions

The analysis showed that SMI is effective, repeatable, and comparable with the CEUS modality in identification endoleaks after EVAR; it may be considered as a potential tool to monitor patients after EVAR implantation, especially those with renal insufficiency or with an allergy to any contrast media.

  相似文献   
59.
Purpose

The purpose of the study was to determine if the ≥ 15 mm threshold currently used to define PIRADS 5 lesions is the optimal size threshold for predicting high likelihood of clinically significant (CS) cancers.

Materials

Three hundred and fifty-eight lesions that may be changed from category 4 to 5 or vice versa on the basis of the size criterion (category 4: n = 288, category 5: n = 70) from 255 patients were evaluated. Kendall’s tau-b statistic accounting for inter-lesion correlation, generalized estimation equation logistic regression, and receiver operating curve analysis evaluated two lesion size-metrics (lesion diameter and relative lesion diameter—defined as lesion diameter/prostate volume) for ability to identify CS (Gleason grade ≥ 3 + 4) cancer at targeted biopsy. Optimal cut-points were identified using the Youden index. Analyses were performed for the whole prostate (WP) and zone-specific sub-cohorts of lesions in the peripheral and transition zones (PZ and TZ).

Results

Lesion diameter showed a modest correlation with Gleason grade (WP: τB = 0.21, p < 0.0001; PZ: τB = 0.13, p = 0.02; TZ: τB = 0.32, p = 0.001), and association with CS cancer detection (WP: AUC = 0.63, PZ: AUC = 0.59, TZ: AUC = 0.74). Empirically derived thresholds (WP: 14 mm, PZ: 13 mm, TZ: 16 mm) performed similarly to the current ≥ 15 mm standard. Lesion relative lesion diameter improved identification of CS cancers compared to lesion diameter alone (WP: τB = 0.30, PZ: τB = 0.24, TZ: τB = 0.42, all p < 0.0001). AUC also improved for WP and PZ lesions (WP: AUC = 0.70, PZ: AUC = 0.68, and TZ: AUC = 0.74).

Conclusions

The current ≥ 15 mm diameter threshold is a reasonable delineator of PI-RADS category 4 and category 5 lesions in the absence of extraprostatic extension to predict CS cancers. Additionally, relative lesion diameter can improve identification of CS cancers and may serve as another option for distinguishing category 4 and 5 lesions.

  相似文献   
60.
Background: Lactobacillus plantarum 299v (LP299v) has been used in order to reduce gastrointestinal symptoms during antibiotic exposure. However, it remains controversial whether or not probiotics are effective in the prevention of Clostridium difficile infections (CDI) among patients receiving antibiotics. The aim of this study was to analyze the CDI among patients receiving antibiotics and hospitalized in the period before and after starting routine use of LP299v as a prevention of this infection. Methods: Among 3533 patients hospitalized in the nephrology and transplantation ward during a two-year period, 23 patients with CDI were diagnosed and enrolled in this retrospective study. Since November 2013, prevention of CDI with oral use of LP299v was performed in all patients treated with antibiotics and who were at a high risk of developing CDI. The observation period was divided into two twelve-month intervals before and after initiation of the use of LP299v as a prophylactic against CDI. Results: A significant (p = 0.0001) reduction of the number of cases of CDI was found after routinely using LP299v (n = 2; 0.11% of all hospitalized patients) compared with the previous twelve-month period of observation (n = 21; 1.21% of all hospitalized patients). Conclusions: Routine use of LP299v during treatment with antibiotics may prevent C. difficile infection in the nephrology and transplantation ward.  相似文献   
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