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51.
Plants naturally produce chemical compounds, which are used to endorse health and fight against diseases and have been used traditionally. Nigella sativa (N. sativa) has a broad spectrum of usage in traditional folk medicines and it's a well-known medicinal herb in ancient Ayurveda, Siddha, Chinese, Arab and Unani Tibb. N. sativa stimulates the body with its natural vitalizing process and cures the disease. Phytochemically, N. sativa seed contains a wide range of fixed oils, proteins, alkaloids, saponin and essential oils. Most of the medicinal properties of N. sativa are due to the presence of the quinone constituent. Among the constituents of N. sativa, thymoquinone is one of the predominant bioactive compounds. The aim of this review is to explore the phytochemical, therapeutical and pharmacological potentials of N. sativa. N. sativa reported to have many therapeutical and pharmacological actions which includes antioxidant, antimicrobial, antidiabetic, anticancer, anti-inflammatory, immunomodulator, cardioprotective, antihyperlipidemic, pulmonary protective, hepatoprotective, nephroprotective, gastroprotective, diuretics, anti-osteoporotic, dermatologic, neuroprotective effects and also has stimulative action on the reproductive system. N. sativa seeds and its derivatives have to be isolated and further investigations should be done using animal models and clinical trials to understand its novel molecular mechanism of action. So, N. sativa and the plant derived constituents can be used in the production of new drug and to treat several diseases.  相似文献   
52.
INTRODUCTION: The use of mycophenolate mofetil (MMF) in renal transplantation results in a 50% lower incidence of acute rejection compared to azathioprine (AZA). However, the graft survival reports are conflicting: the European trial and US database analysis suggest better survival with MMF, an observation that was not seen in the US and tricontinental studies. METHODS: We retrospectively reviewed our single-center experience (60% African-Americans) comparing the serum creatinine (SCr) values and 3-year actual graft survival with MMF versus AZA-based immunosuppression. Group I included patients transplanted between January 1990 and December 1992 on cyclosporine (CSA), AZA, and steroids; group II subjects, from January 1996 to December 1998 on CSA, MMF, and steroids. We analyzed SCr and all causes of graft losses at 3, 6, 12, 18, 24, and 36 months posttransplantation. RESULTS: The patient demographics were similar in both groups as was the mean SCr values at different times. The time-group interaction for SCr, the Kruskal-Wallis test for SCr for different categories (<1.5, 1.5 to 2.0, 2.0 to 2.5, and >2.5 mg/dL) and the all-cause graft loss between the two groups were not significantly different. CONCLUSION: Our results failed to show better long-term actual graft survival despite the 6-year interval between the two groups. These findings agree with the results of the United States and the tricontinental studies. A lower incidence of acute rejection early after transplantation observed with MMF may not always translate into a long-term benefit, possibly due to the influence of nonimmunological factors, such as hypertension, calcineurin inhibitor toxicity, more frequent cytomegalovirus infections, and increased attempts to withdraw steroids using MMF-based protocols.  相似文献   
53.
An ideal method for quality of life (QOL) assessment in renal transplant recipients (RTR) has not yet been determined. Present assessments of QOL in RTR are lengthy, cumbersome to administer, and difficult to interpret. We used a previously validated single question QOL scale score (QLS) that directly asks about the patients' overall assessment of their QOL; "Considering all parts of my life-physical, emotional, social, spiritual, and financial--over the past 2 days the quality of my life has been ... ". The QLS ranges from 0 ("very bad") to 10 ("excellent"). Patients were contacted prior to their routine office visit when they were free of acute medical problems. Fifty RTR participated. Psychosocial and medical variables included the Beck Depression Inventory, Illness Effects Questionnaire, Multidimensional Scale of Perceived Social Support, time since transplant, age, creatinine, hemoglobin, and albumin levels. Of the patients, 64% were African-American and 48% were women; 94% of patients had a score>5. Mean QLS was 7.5+/-2.3. Perception of a better QOL correlated with less perception of depression and illness effects and with perception of greater social support and satisfaction with life (all P<.05). Perception of QOL did not correlate with age, time since transplantation, creatinine, hemoglobin or albumin levels. We concluded that QLS is a quick tool to measure subjective QOL in RTR for correlation with psychosocial factors of interest in this group. These studies should be replicated in larger multiethnic populations.  相似文献   
54.
Introduction of axial chirality in bioactive 3-indolyl furanoids has been achieved by systematic alteration of functional groups around the stereogenic axis, keeping in mind that atropisomerically pure analogues may possess different binding affinities and selectivities towards a target protein. The kinetics of racemization of axially chiral 3-indolyl furanoids have been studied through chiral HPLC analysis, electronic circular dichroism (ECD) spectroscopy, and computational modeling. The results identify the configurational parameters for optically pure 3-indolyl furanoids to exist as stable and isolable atropisomeric form.

A number of axially chiral 3-indolyl furanoids have been synthesized and the individual enantiomers are found to be configurationally stable and isolable at room temperature.  相似文献   
55.

Background

Successful kidney transplantation despite positive crossmatch (+CXM) before transplantation is well recognized in combined liver-kidney transplant (CLKT) recipients. This is probably due to immunologic protection of the renal allograft (RA) conferred by the liver allograft. However, occurrences of antibody-mediated rejection and poor long-term RA outcome is also documented with +CXM CLKT recipients, suggesting that such immunologic protection may not be universal.

Methods

A total of 1,401 CLKT recipients with known status of pre-transplantation CXM were identified from the United Network for Organ Sharing registry from January 1, 1986, to December 31, 2006. Univariate analysis for significant differences in clinical variables and Kaplan-Meier estimate for patient and graft survivals were performed. The results were compared between positive and negative CXM groups.

Results

Pre-transplantation +CXM was seen in 17.3% (242/1401) of CLKT recipients studied. The demographic and clinical characteristics were similar between the groups, except for higher panel reactive antibody level and CXM positivity in female recipients. Outcome analysis showed higher RA rejection (19.3% vs 10.8%; P = .026) and increased hospital length of stay (37.3 ± 46.0 vs 28.8 ± 33.2 days; P = .028) in the +CXM group. RA survivals at 1, 3, and 5 years were 8%, 7%, and 6% lower in the +CXM group. The patient and liver allograft survivals were not different between the groups.

Conclusions

In CLKT recipients with pre-transplantation +CXM, the immunologic protection of RA conferred by the liver allograft is less robust than previously perceived and may lead to higher rejection rate and poor RA outcome. This can be mitigated with routine pre-transplantation CXM.  相似文献   
56.
The search for suitable materials for carbon dioxide capture and storage has attracted the attention of the scientific community in view of the increased global CO2 levels and its after-effects. Among the different materials under research, porous carbons and their doped analogues are extensively debated for their ability to store carbon dioxide at high pressures. The present paper examined high-pressure carbon dioxide storage studies of 1-D hexagonal and 3-D cubic ordered mesoporous pristine and N-doped carbons prepared using the nano-casting method. Excess carbon dioxide sorption isotherms were obtained using the volumetric technique and were fitted using the Toth model. Various parameters that influence CO2 storage on metal-free ordered mesoporous carbons, such as the effect of pore size, pore dimension, pyrolysis temperature, the impact of nitrogen substitution, and the effect of ammonia activation are discussed. It was observed that the carbon dioxide storage capacity has an inverse relation to the total nitrogen doped, the amount of pyridinic nitrogen functionality, and the pyrolysis temperature, whereas the pore size seems to have a linear relationship. On the other hand, the presence of oxygen has a positive effect on the sorption capacity. Among the prepared ordered mesoporous carbons, the ammonia-treated one has shown the highest adsorption capacity of 37.8 mmol g−1 at 34 bar and 0 °C.

The present paper discusses the shaping factors of metal-free ordered mesoporous carbon synthesis for carbon dioxide sorption at high pressures. These results can be used as future guidelines in preparing carbon for gas adsorption studies.  相似文献   
57.
To assess the contribution of the protein content of urine from the native kidneys to post-transplant proteinuria, we prospectively studied 14 live donor transplant recipients with a pre-transplant random urine protein to creatinine ratio (UPr:Cr) >0.5. Seven patients received preemptive transplants, and seven patients were on dialysis pre-transplant (with residual urine output). Resolution of proteinuria was defined as UPr:Cr < 0.2. Immunosuppression consisted of tacrolimus, mycophenolate mofetil and corticosteroids. Anti-hypertensive drugs that might reduce proteinuria were avoided during the study. The serum creatinine was 8.7 +/- 0.7 mg/dL pre-transplant, and the nadir post-transplant serum creatinine was 1.4 +/- 0.1 mg/dL. The pre-transplant UPr:Cr ranged between 0.5 and 9.2 (mean = 2.9 +/- 0.6). The UPr:Cr decreased to <0.2 in all 14 patients at a mean of 4.5 weeks post-transplant (range 1-10 weeks). In conclusion, in live donor renal transplant recipients with immediate graft function, proteinuria of native kidney origin resolves in the early post-transplant period. After the immediate post-transplant period, proteinuria cannot be attributed to the native kidneys, and work up for proteinuria should focus on the allograft.  相似文献   
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60.
Interacting with others in the environment requires that we perceive and recognize their movements and actions. Neuroimaging and neuropsychological studies have indicated that a number of brain regions, particularly the superior temporal sulcus, are involved in a number of processes essential for action recognition, including the processing of biological motion and processing the intentions of actions. We review the behavioral and neuroimaging evidence suggesting that while some aspects of action recognition might be rapid and effective, they are not necessarily automatic. Attention is particularly important when visual information about actions is degraded or ambiguous, or if competing information is present. We present evidence indicating that neural responses associated with the processing of biological motion are strongly modulated by attention. In addition, behavioral and neuroimaging evidence shows that drawing inferences from the actions of others is attentionally demanding. The role of attention in action observation has implications for everyday social interactions and workplace applications that depend on observing, understanding and interpreting actions.  相似文献   
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