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81.
Bulletin of Environmental Contamination and Toxicology - The safe utilization and risk assessment of produced water (PW) from oil and gas fields for desert irrigation have received increasing...  相似文献   
82.
Research letters     
Patients with transfusion-dependent thalassemia are expected to have an unfavorable quality of life due to multiple factors. We studied the quality of life in 72 patients (age 5-39 y) with transfusion-dependent thalassemia in the era of improved care, and assessed different parameters affecting it.  相似文献   
83.
Bliwise DL  Ansari FP 《Sleep》2007,30(7):881-884
STUDY OBJECTIVE: Many people use dietary supplements or herbal products to help them sleep. We analyzed the associations between melatonin use and insomnia and between valerian use and insomnia in a representative sample of the United States population. DESIGN AND PARTICIPANTS: The data reported upon here were collected in the 2002 Alternative Health/Complementary and Alternative Medicine (CAM) Supplement to the National Health Interview Survey. This was a survey of 31,044 personal interviews that constituted an age-representative and socioeconomically representative sample of the civilian noninstitutionalized population of the United States. RESULTS: Of the survey sample, 5.9% used valerian and 5.2% used melatonin. Of those using valerian, 29.9% endorsed insomnia as 1 reason for CAM use, and, of melatonin users, 27.5% endorsed insomnia as 1 reason for CAM use. Relatively greater use occurred in individuals under age 60 years. The decision to use such substances was made in consultation with a health care provider less than half of the time. CONCLUSIONS: Large segments of the United States population used valerian or melatonin for insomnia within the year preceding the survey, and usage typically fell outside the purview of the health care system.  相似文献   
84.
Whilst many physiological functions of nitric oxide (NO) have been revealed so far, recent evidence proposes an essential role for NO in T lymphocyte activation and signal transduction. NO acts as a second messenger, activating soluble guanyl cyclase and participating in signal transduction pathways involving cyclic GMP. NO modulates mitochondrial events that are involved in apoptosis and regulates mitochondrial biogenesis in many cell types, including lymphocytes. Several studies undertaken on patients with RA and SLE have documented increased endogenous NO synthesis, although the effects of NO may be distinct. Here, we discuss recent evidence that NO contributes to T cell dysfunction in both SLE and RA by altering multiple signaling pathways in T cells. Although NO may play a physiological role in lymphocyte cell signaling, its overproduction may perturb T cell activation, differentiation and effector responses, each of which may contribute in different ways to the pathogenesis of autoimmunity.  相似文献   
85.
OBJECTIVE: This study compares telephone consultations with the results of clinical examinations to assess the value and accuracy of telephone consultations for the future planning in a breast cancer clinic in Tehran, Iran. METHODS: In 2500 telephone calls, 800 Symptomatic patients were identified and asked to visit the center for the further investigations by the specialists. The agreement between two observers data were compared by the kappa statistic. RESULTS: Totally 174 patients complied with the recommendation and included in the study. The most common chief complaints of visitors were: breast mass (42%) and breast pain (35%). Kappa statistic showed a very good agreement (K=0.62, P<0.001) between consultants' diagnosis and the specialists findings. This agreement for breast cancer diagnosis, although lower, was also good (K=0.55, P<0.001). CONCLUSION: The study findings indicate that consultants may diagnose and manage some common conditions via telephone, usually following the established protocols. More studies are needed to determine the economic and logistic advantages of telephone consultations. PRACTICE IMPLICATIONS: By assessment of strength and weakness of this service, it is possible to develop an easy to use information system for women who need breast care.  相似文献   
86.
Ecotoxicology - Bracon hebetor Say (Hymenoptera: Braconidae) is an important biological control agent of various species of order Lepidoptera and extensively used in biological control program...  相似文献   
87.
Cerebrospinal fluid (CSF) drains via the lymphatic drainage pathway. This lymphatic pathway connects the central nervous system (CNS) to the cervical lymph node (CLN). As the CSF drains to CLN via the dural and nasal lymphatics, T cells and antigen presenting cells pass along the channels from the subarachnoid space through the cribriform plate. Human immunodeficiency virus (HIV) may also egress from the CNS along this pathway. As a result, HIV egressing from the CNS may accumulate within the CLN. Towards this objective, we analyzed CLNs isolated from rhesus macaques that were chronically-infected with simian immunodeficiency virus (SIV). We detected significant accumulation of SIV within the CLNs. SIV virion trapping was observed on follicular dendritic cells (FDCs) localized within the follicular regions of CLNs. In addition, SIV antigens formed immune complexes when FDCs interacted with B cells within the germinal centers. Subsequent interaction of these B cells with CD4+ T follicular helper cells (TFHs) resulted in infection of the latter. Of note, 73% to 90% of the TFHs cells within CLNs were positive for SIV p27 antigen. As such, it appears that not only do the FDCs retain SIV they also transmit them (via B cells) to TFHs within these CLNs. This interaction results in infection of TFHs in the CLNs. Based on these observations, we infer that FDCs within the CLNs have a novel role in SIV entrapment with implications for viral trafficking.  相似文献   
88.
89.
Although the use of induction therapy has reduced the risk of acute rejection after heart transplantation, its use may be associated with other adverse outcomes. We aimed to examine the effect of no induction (NoInd), induction with basiliximab (BAS), or induction with antithymocyte globulin (ATG) on outcome after heart transplantation. We analyzed data from the International Society for Heart and Lung Transplantation (ISHLT) registry for adult heart transplants performed between 2000 and 2013. The primary outcome was cumulative all-cause mortality, and the secondary outcome was cause-specific death. We identified 27 369 transplants whose recipients received NoInd (n = 15 688), ATG (n = 6830), or BAS (n = 4851). Over a median follow-up of 1497 days, overall 30-day mortality was 5% and 1-year mortality was 11%. Survival after transplant was similar in patients treated with NoInd compared with ATG. The survival was improved using NoInd compared with BAS (log-rank P = .040), adjustment HR = 1.11 (95% CI, 1.04-1.19). Compared to NoInd, BAS was associated with higher risk of graft failure-related deaths, HR = 1.27 (95% CI, 1.02-1.58), and ATG was associated with higher risk of malignancy-related deaths, HR = 1.18 (95% CI, 1.01-1.39). Survival of patients who received NoInd was similar to ATG and better compared with BAS. Further, the use of ATG may be associated with increased malignancy-related mortality, compared with NoInd.  相似文献   
90.
This study aimed to investigate the electro-degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solution using two and three-dimensional electrode (2D and 3D) reactors with graphite(G)/β-PbO2 anode. To increase the degradation efficiency, affecting parameters on the electro-degradation process were investigated and optimized by adopting the Taguchi design of experiments approach. The structure, morphology and electrochemical properties of the electrodes were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), linear sweep voltammetry and cyclic voltammograms. The controllable factors, i.e., electrolysis time, 2,4-D initial concentration, solution pH and current density (j) were optimized. Under optimum conditions, the 2,4-D degradation efficiency was 75.6% using 2D and 93.5% using 3D electrode processes. The percentage contribution of each controllable factor was also determined. The pH of the solution was identified as the most influential factor, and its percentage contribution value was up to 39.9% and 40.4% for 2D and 3D electrode processes, respectively. Considering the parameters of the kinetics, it was found that the degradation of 2,4-D and removal of COD using the G/β-PbO2 electrode obey the pseudo-first order kinetics. In addition, the mineralization pathway of 2,4-D at G/β-PbO2 electrode was proposed. The results also demonstrated that the 3D electrode process with G/β-PbO2 anode can be considered as a useful method for degradation and mineralization of 2,4-D herbicides from aqueous solution.

Optimization of process parameters using the Taguchi method, electrochemical degradation and electrochemical degradation mechanism of 2,4-D herbicide using 2D and 3D reactors with G/β-PbO2 anode were investigated.  相似文献   
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