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71.
Correction for ‘Regulation of nitrogen dynamics at the sediment–water interface during HAB degradation and subsequent reoccurrence’ by Weiping Sima et al., RSC Adv., 2020, 10, 13480–13488, DOI: 10.1039/c9ra10673a.

The authors regret that the affiliations of three of the authors (Hong Li, Hainan Ai and Hao Zhan) were shown incorrectly in the original article. The corrected author list and affiliations are as shown above.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.  相似文献   
72.
The effects of harmful algal blooms (HABs) on nutrient dynamics have been extensively studied; however, the response of nitrogen to continuous HAB degradation and subsequent reoccurrence is not well understood. Here, a small-scale experiment was conducted to assess how nitrogen in the sediment–water interface (SWI) responds to HAB degradation and subsequent reoccurrence at different initial algal densities. The results showed that during the algae decomposition stage, the NH4+–N flux of the SWI remained positive but decreased with the increase in algal density from 3.5 × 107 to 2.3 × 108 cells per L, indicating that the sediment was the source of NH4+–N. In contrast, the deposit was a sink of NO3–N. However, during the reoccurrence of HAB, the distribution of NH4+–N and NO3–N fluxes was completely converted. Nitrogen flux analysis throughout algae decomposition and reoccurrence indicated that although the sediment acted as a sink of nitrogen, the flux was dependent on the initial algal density. Our results confirmed that algae decomposition and reoccurrence would greatly affect the nitrogen cycle of the SWI, during which dissolved oxygen (DO) and initial algal density dominated. This study is the first to show that the regulation of nitrogen flux and migration changes during continuous HAB decomposition and subsequent reoccurrence.

The effects of harmful algal blooms (HABs) on nutrient dynamics have been extensively studied; however, the response of nitrogen to continuous HAB degradation and subsequent reoccurrence is not well understood.  相似文献   
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BACKGROUND/AIMS: Although a "hospital-based cancer registry" is important in improving patient care, a "population-based cancer registry" with emphasis on epidemiology is important in allocating health care resources and prioritizing public health programs. Because of its reliance on retrieved clinical and para-clinical documents, there is some limitation in registering all cancer incidents in this system, especially in developing countries. In this study we examined the possibility of using public data as a complementary source of information for recording cancers in a population-based cancer registry. METHODS: Along with the annual census in rural areas, a survey was performed in Golestan province in March 2004 to identify public awareness about cancer incidents in the community. Individuals were questioned about history of cancer in their close relatives during the last two years. Those who reported cancer in their relatives were also asked to name the main organ of involvement. A similar list was retrieved from the cancer registry at the Ministry of Health in Gorgan, and cases with upper GI (esophagus and gastric) cancer diagnosis from 21 March 2002 through 20 March 2004 were selected for this study. Finally, these two lists were compared for examining accuracy of the collected data. RESULTS: We included 137 cases in our study with rural residence and known addresses. Only 35 (25.5%) cases were reported by the relatives and among them only 20 (57.1%) relatives correctly reported the tumor location. Although we found a difference in accurate reporting of cancer incidents by year of diagnosis (more correct cases reported during the second versus the first year), the difference was not statistically significant between the two years. CONCLUSION: In this study, we examined the possibility of using public awareness about cancer incidents as a complementary source of information for a population-based cancer registry. We found that this approach is not ideal for reducing limitations. Therefore, we recommend a nationwide cancer registry to record all cancer-related information at the time of diagnosis. This strategy will reduce the need for performing retrospective surveys in collecting cancer-related information.  相似文献   
76.
Mohandas  N; Lie-Injo  LE; Friedman  M; Mak  JW 《Blood》1984,63(6):1385-1392
A high frequency of nonhemolytic hereditary ovalocytosis in Malayan aborigines is thought to result from reduced susceptibility of affected individuals to malaria. Indeed, Kidson et al. recently showed that ovalocytes from Melanesians in Papua New Guinea are resistant to infection in culture by the malarial parasite Plasmodium falciparum. In order to determine if protection against parasitic invasion in these ovalocytes might be the result of some altered membrane material property in these unusual cells, we measured their membrane and cellular deformability characteristics using an ektacytometer . Ovalocytic red cells were found to be much less deformable in comparison to normal discoid red cells. Similar measurements on isolated membrane preparations revealed a marked reduction in ovalocytic membrane deformability. To produce equal deformation of ovalocytic and normal membranes, ovalocytes required an 8-10-fold increase in applied shear stress, indicating that their membrane was capable of deforming under sufficient stress. To test the possibility that this increased membrane rigidity might confer resistance to parasitic invasion, we performed an in vitro invasion assay using Plasmodium falciparum merozoites and Malayan ovalocytes of varying deformability from seven different donors. The level of infection of the ovalocytes ranged from 1% to 35% of that in control cells, and the extent of inhibition appeared to be closely related to the reduction in membrane deformability. Moreover, we were able to induce similar resistance to parasitic invasion in nonovalocytic normal red cells by increasing their membrane rigidity with graded exposure to a protein crosslinking agent. Our findings suggest that resistance to parasite invasion of Malayan ovalocytes is the result of a genetic mutation that causes increased membrane rigidity.  相似文献   
77.

Background

Laparoscopic gastric bypass (LGBP) is the most common bariatric procedure worldwide. The gastrojejunostomy can be stapled with a circular or linear stapler, each with their own specific advantages. We have evaluated differences in postoperative complications between the two techniques.

Methods

We studied operative data and postoperative complications in 560 patients (79.8 % females, median age 42, BMI 42.5) operated with LGBP between 2008 and 2012 at our center. The gastrojejunostomy was initially performed using a circular stapler (CS) in 288 patients and later by linear stapler (LS) in 272. Complications, operative time, and length of stay were retrieved from our database. The risk of developing a port site infection was evaluated with multivariate logistic regression.

Results

Port site infections were more common with CS than LS, 5.2 and 0.4 %, respectively (p?<?0.01). Multivariate analysis demonstrated CS to be an independent risk factor for port site infections (OR 16.3 (2.09–126), p?<?0.01), as well as for stomal ulcers (OR 10.1, 1.15–89, p?=?0.04). Major postoperative complications remained unchanged (anastomotic leak 1.0 vs. 1.1 %, abscess 0.7 vs. 0.4 %), while operative time and length of stay were found to be shorter using the LS (122 vs. 83 min, p?<?0.001 and 4 vs. 3 days, p?<?0.001).

Conclusions

The linear stapled technique yielded lower incidence of port site infections, probably by avoiding the passage of a contaminated circular stapler through the abdominal wall. No difference in major complications was seen, but operative time was shorter using a linear stapler instead of a circular stapler.  相似文献   
78.
In this work, antitumor compounds, lactoferrin [recombinant iron-free (Apo-rLf)], cisplatin (Cis) or their combination were embedded within a biodegradable polycaprolactone (PCL) polymer thin film, by a modified approach of a laser-based technique, matrix-assisted pulsed laser evaporation (MAPLE). The structural and morphological properties of the deposited hybrid films were analyzed by Fourier-transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). The in vitro effect on the cells’ morphology and proliferation of murine melanoma B16-F10 cells was investigated and correlated with the films’ surface chemistry and topography. Biological assays revealed decreased viability and proliferation, lower adherence, and morphological modifications in the case of melanoma cells cultured on both Apo-rLf and Cis thin films. The antitumor effect was enhanced by deposition of Apo-rLf with Cis within the same film. The unique capability of the new approach, based on MAPLE, to embed antitumor active factors within a biodegradable matrix for obtaining novel biodegradable hybrid platform with increased antitumor efficiency has been demonstrated.  相似文献   
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胡熹白  方长海  程广金  乐剑平  汪源 《西部医学》2024,36(1):148-151+156
目的 探讨双源CT联合血清C反应蛋白(CRP)水平检测对痛风性关节炎的诊断价值。方法 选择本院2018年1月—2022年3月收治的166例疑似痛风性关节炎患者,分为痛风性关节炎组与非痛风性关节炎组行双源CT及血清CRP水平检测,以美国风湿病协会(ACR)制定的痛风性关节炎诊断标准明确痛风性关节炎诊断,计算双源CT及血清CRP单独与联合诊断痛风性关节炎的效能并分析其临床价值。结果 共有126例患者(75.90%)明确痛风性关节炎诊断。痛风性关节炎组双源CT图像绿色结晶检出率高于非痛风性关节炎组,差异有统计学意义(P<0.05)。痛风性关节炎组血清CRP水平高于非痛风性关节炎组(P<0.05),但两组血清CRP阳性率比较,差异无统计学意义(P>0.05)。双源CT联合血清CRP诊断痛风性关节炎的特异性、准确率、阳性预测值、阴性预测值均高于单项诊断,差异有统计学意义(P<0.05)。结论 双源CT联合血清CRP水平检测能够为痛风性关节炎的无创诊断提供可靠参考  相似文献   
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