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41.
The placebo problem remains   总被引:1,自引:0,他引:1  
  相似文献   
42.
PURPOSE: Intestinal non-Hodgkin's lymphomas are not well characterized. We therefore studied prospectively their clinical features and response to standardized therapy. PATIENTS AND METHODS: Fifty-six patients with primary intestinal lymphoma were included in a prospective, nonrandomized multicenter study. Lymphoma resection was recommended and staging was performed according to the Ann Arbor classification. Patients were scheduled to receive six cycles of cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) chemotherapy, and at stages EIII to EIV, they received additional involved-field radiotherapy. Corticosteroids were used in patients who could not receive chemotherapy. RESULTS: Thirty-five patients had intestinal T-cell lymphoma (ITCL), 21 patients had intestinal B-cell lymphoma (IBCL; 18 diffuse large-cell lymphomas, two marginal-cell lymphomas, and one follicle-center lymphoma). Thirty-four patients at stages EI to EII (14 ITCL and 20 IBCL) and nine patients at stages EIII to EIV (all ITCL) received chemotherapy. No patient in stages EIII to EIV received radiotherapy, because death occurred in 12 of 14 patients. Two-year cumulative survival in patients with IBCL was 94% (95% CI, 82% to 100%) and higher than in patients with ITCL (28% [95% CI, 13% to 43%]; P <.0001), even when only stages EI to EII were considered (ITCL, 37.5% [95% CI, 16.5% to 58.5%]; P <.0001). IBCL patients compared with ITCL patients were at lower lymphoma stages (P <.01), had higher Karnofsky status (P <.005), had intestinal perforation less often (P <.05), required emergency operation less often (P <.05), received CHOP (P <.05) more often, and reached complete remission (P <.0005) more frequently. CONCLUSION: IBCL patients at stages EI and EII respond well to chemotherapy, but the prognosis and treatment of ITCL patients is unsatisfactory.  相似文献   
43.
Sentinox (STX) is an acid-oxidizing solution containing hypochlorous acid in spray whose virucidal activity against SARS-CoV-2 has been demonstrated. In this paper, results of a randomized controlled trial (RCT) on the efficacy of STX in reducing viral load in mild COVID-19 patients (NCT04909996) and a complementary in vitro study on its activity against different respiratory viruses are reported. In the RCT, 57 patients were randomized (1:1:1) to receive STX three (STX-3) or five (STX-5) times/day plus standard therapy or standard therapy only (controls). Compared with controls, the log10 load reduction in groups STX-3 and STX-5 was 1.02 (p = 0.14) and 0.18 (p = 0.80), respectively. These results were likely driven by outliers with extreme baseline viral loads. When considering subjects with baseline cycle threshold values of 20–30, STX-3 showed a significant (p = 0.016) 2.01 log10 reduction. The proportion of subjects that turned negative by the end of treatment (day 5) was significantly higher in the STX-3 group than in controls, suggesting a shorter virus clearance time. STX was safe and well-tolerated. In the in vitro study, ≥99.9% reduction in titers against common respiratory viruses was observed. STX is a safe device with large virucidal spectrum and may reduce viral loads in mild COVID-19 patients.  相似文献   
44.
The hydrothermal alteration of perlite into zeolites was studied using a two-step approach. Firstly, perlite powder was transformed into Na-P1 (GIS) or hydro(xy)sodalite (SOD) zeolites at 100 °C and 24 h using 2 or 5 M NaOH solutions. Secondly, the Si:Al molar ratio of the reacted Si-rich solution was adjusted to 1 by Na-aluminate addition to produce zeolite A (LTA) at 65 or 95 °C and 6 or 24 h at an efficiency of 90 ± 9% for Al and 93 ± 6% for Si conversion. The performance of these zeolites for metal ion removal and water softening applications was assessed by sorption experiments using an artificial waste solution containing 4 mmol/L of metal ions (Me2+: Ca2+, Mg2+, Ba2+ and Zn2+) and local tap water (2.1 mmol/L Ca2+ and 0.6 mmol/L Mg2+) at 25 °C. The removal capacity of the LTA-zeolite ranged from 2.69 to 2.86 mmol/g for Me2+ (=240–275 mg/g), which is similar to commercial zeolite A (2.73 mmol/g) and GIS-zeolite (2.69 mmol/g), and significantly higher compared to the perlite powder (0.56 mmol/g) and SOD-zeolite (0.88 mmol/g). The best-performing LTA-zeolite removed 99.8% Ca2+ and 93.4% Mg2+ from tap water. Our results demonstrate the applicability of the LTA-zeolites from perlite for water treatment and softening applications.  相似文献   
45.
ObjectiveTo investigate the diagnostic accuracy of the sentinel node procedure in patients with vulvar cancer, a multicenter study was launched in Germany in 2003 involving 7 oncology centers.Patients and methodsBetween 2003 and 2006, 127 women with primary T1–T3 vulvar cancer were entered in the study and treated with sentinel node removal after application of 99mTechnetium labeled nanocolloid and/or blue dye. Subsequently, in all women a complete inguinofemoral lymphadenectomy and the adequate vulvar operation were performed. Sentinel lymph nodes were examined by routine pathologic examination (H&;E), followed by step-sectioning and immunhistochemistry if negative.ResultsThe sentinel node procedure was successful in 125 out of 127 cases, in 2 cases no sentinel nodes were detected. 21 patients received unilateral lymphadenectomy, 103 women were operated on both groins. In 39 women out of 127, positive lymph nodes in one or both groins were identified (30.7%). In 36 women, the sentinel nodes were also positive (sensitivity 92.3%). We had three cases with a false negative sentinel node (false negative rate: 7.7%), all of these women presenting with tumors in midline position. One tumor was a T1 tumor (10 mm), 2 tumors being classified as T2 (40 and 56 mm, respectively). In one additional case (18 mm T1 tumor, midline position), the sentinel was positive in the right groin, but false negative on the left side.ConclusionsThis study shows that identification of SLN in squamous cell cancer of the vulva is feasible, however not highly accurate depending on tumor localization and size. The false negative rate seems to be acceptable if the procedure is restricted to stage 1 tumors with clinically negative lymph node status. Tumors situated in or close to the midline seem to be less suitable for this procedure. Implementation of SLNB into clinical practice should be performed with care and only by experienced teams as to avoid preventable groin relapses.  相似文献   
46.
P Reiner  V Ujházy 《Neoplasma》1980,27(6):711-715
Four separate cell clones were isolated from parental rat RBB/R cell line. Sensitivity of clones to 3-oxauracil varied, and was dependent on the proliferation rate of particular clone. Colony formation method was more appropriate than 3H-thymidine incorporation for determination of post-treatment surviving cells.  相似文献   
47.
48.
Over half the world’s population is at risk for viruses transmitted by Aedes mosquitoes, such as dengue and Zika. The primary vector, Aedes aegypti, thrives in urban environments. Despite decades of effort, cases and geographic range of Aedes-borne viruses (ABVs) continue to expand. Rigorously proven vector control interventions that measure protective efficacy against ABV diseases are limited to Wolbachia in a single trial in Indonesia and do not include any chemical intervention. Spatial repellents, a new option for efficient deployment, are designed to decrease human exposure to ABVs by releasing active ingredients into the air that disrupt mosquito–human contact. A parallel, cluster-randomized controlled trial was conducted in Iquitos, Peru, to quantify the impact of a transfluthrin-based spatial repellent on human ABV infection. From 2,907 households across 26 clusters (13 per arm), 1,578 participants were assessed for seroconversion (primary endpoint) by survival analysis. Incidence of acute disease was calculated among 16,683 participants (secondary endpoint). Adult mosquito collections were conducted to compare Ae. aegypti abundance, blood-fed rate, and parity status through mixed-effect difference-in-difference analyses. The spatial repellent significantly reduced ABV infection by 34.1% (one-sided 95% CI lower limit, 6.9%; one-sided P value = 0.0236, z = 1.98). Aedes aegypti abundance and blood-fed rates were significantly reduced by 28.6 (95% CI 24.1%, ∞); z = −9.11) and 12.4% (95% CI 4.2%, ∞); z = −2.43), respectively. Our trial provides conclusive statistical evidence from an appropriately powered, preplanned cluster-randomized controlled clinical trial of the impact of a chemical intervention, in this case a spatial repellent, to reduce the risk of ABV transmission compared to a placebo.

Aedes-borne viral diseases (ABVDs) [e.g., dengue (DENV), chikungunya, Zika (ZIKV), and yellow fever] are devastating, expanding global public health threats that disproportionally affect low- and middle-income countries. DENV, one of the most rapidly increasing vector-borne infectious diseases, results in ∼400 million infections each year (1, 2), with 4 billion people at risk for infection annually (3). Currently, the primary means for ABVD prevention is controlling the primary mosquito vector, Aedes aegypti. Existing vector control interventions, however, have failed to prevent ABV transmission and epidemics (46).There is an urgent need to develop evidence-based guidance for the use of new and existing ABV vector control tools. The evidence base for vector control against ABVs is weak, despite considerable government investments in World Health Organization (WHO)-recommended control of larval habitats (larviciding, container removal) and ultra-low-volume insecticide spraying (4, 5, 79). These strategies continue to be implemented despite the lack of rigorously generated data from controlled clinical trials demonstrating they reduce ABV infection or disease (6). The only ABV intervention with a proven epidemiological impact in a cluster-randomized control trial (cRCT) assessed community mobilization to reduce mosquito larval habitats (10). A recent test-negative trial with Wolbachia-infected mosquitoes reported a significant reduction of DENV illness in Indonesia (11).Spatial repellents (SRs) are devices that contain volatile active ingredients that disperse in air. The active ingredients can repel mosquitoes from entering a treated space, inhibit attraction to human host cues, or disrupt mosquito biting and blood-feeding behavior and, thus, interfere with mosquito–human contact (1214). Any of these outcomes reduce the probability of pathogen transmission. Pyrethroid-based SRs have shown efficacy in reducing malaria infections in China (15) and Indonesia (16). There have, however, been no clinical trials evaluating the protective efficacy (PE) of SRs against ABV infection or disease.To generate evidence for public health consideration, we conducted a double-blinded, parallel cRCT to demonstrate and quantify the PE of a transfluthrin-based SR to reduce ABV infection incidence over 2 y in a human cohort in Iquitos, Peru.  相似文献   
49.
A number of small-molecule poly (ADP-ribose) polymerase (PARP) inhibitors are currently undergoing advanced clinical trials. Determining the distribution and target inhibitory activity of these drugs in individual subjects, however, has proven problematic. Here, we used a PARP agent for positron emission tomography-computed tomography (PET-CT) imaging (18F-BO), which we developed based on the Olaparib scaffold using rapid bioorthogonal conjugation chemistries. We show that the bioorthogonal 18F modification of the parent molecule is simple, highly efficient, and well tolerated, resulting in a half maximal inhibitory concentration (IC50) of 17.9 ± 1.1 nM. Intravital imaging showed ubiquitous distribution of the drug and uptake into cancer cells, with ultimate localization within the nucleus, all of which were inhibitable. Whole-body PET-CT imaging showed tumoral uptake of the drug, which decreased significantly, after a daily dose of Olaparib. Standard 18F-fludeoxyglucose imaging, however, failed to detect such therapy-induced changes. This research represents a step toward developing a more generic approach for the rapid codevelopment of companion imaging agents based on small-molecule therapeutic inhibitors.  相似文献   
50.
Endometrial carcinoma (EnCa) is the most common invasive gynaecologic carcinoma. Over 85% of EnCa are classified as endometrioid, expressing steroid hormone receptors and mostly involving pathological prestages. Human endogenous retroviruses (ERV) are chromosomally integrated genes, account for about 8% of the human genome and are implicated in the etiology of carcinomas. The majority of ERV envelope (env) coding genes are either not present or not consistently represented between common gene expression microarrays. The aim of this study was to analyse the absolute gene expression of all known 21 ERV env genes including 19 codogenic and two env genes with premature stop codons in EnCa, endometrium as well as in hyperplasia and polyps. For EnCa seven env genes had high expression with >200 mol/ng cDNA (e.g. envH1-3, Syncytin-1, envT), two middle >50 mol/ng cDNA (envFc2, erv-3) and 12 low <50 mol/ng cDNA (e.g. Syncytin-2, envV2). Regarding tumor parameters, Syncytin-1 and Syncytin-2 were significantly over-expressed in advanced stage pT2 compared to pT1b. In less differentiated EnCa Syncytin-1, erv-3, envT and envFc2 were significantly over-expressed. Syncytin-1, Syncytin-2 and erv-3 were specific to glandular epithelial cells of polyps, hyperplasia and EnCa using immunohistochemistry. An analysis of 10 patient-matched EnCa with endometrium revealed that the ERV-W 5'' long terminal repeat regulating Syncytin-1 was hypomethylated, including the ERE and CRE overlapping MeCP2 sites. Functional analyses showed that 10 env genes were regulated by methylation in EnCa using the RL95-2 cell line. In conclusion, over-expressed env genes could serve as indicators for pathological pre-stages and EnCa.  相似文献   
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