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In this paper, an efficient and straightforward synthetic approach for the preparation of a number of symmetric carboxylic anhydrides was reported using Cu2(BDC)2(DABCO) as an efficient heterogeneous catalyst via the C–H bond activation of aldehydes with excellent yields and simple work up. This C–H bond activation reaction appears simple and convenient, has a wide substrate scope and makes use of cheap, abundant, and easily available reagents. The Cu-MOF catalyst was recycled and reused four times without any loss of catalytic activity.

In this paper, an efficient synthetic method for the preparation of symmetric carboxylic anhydrides was reported using Cu2(BDC)2(DABCO) as an efficient heterogeneous catalyst via the C–H bond activation of aldehydes with good yields and simple work up.  相似文献   
55.

Background:

Visceral leishmaniasis (VL) as one of the most important human parasitic disease is endemic in some parts of Iran. Several cases of VL have been reported recently in the Ilam Province. The current study aimed to assess the present status of human VL in the region.

Methods:

A random cluster sampling method was used to collect 456 serums samples from the children up to 12 years of age and 10% of adults living in urban and rural areas of the province. All the collected serum samples were tested by direct agglutination test (DAT) to detect anti- Leishmania infantum antibodies.

Results:

Of the examined 456 serum samples with direct agglutination test (DAT), only 21 (0.43%) sera showed anti- Leishmania antibodies at titers 1:400 and higher. Distribution of anti- Leishmania antibodies titers were: 1:400(n=4), 1:800(n=11), 1:1600(n=3), 1:3200(n=1), and 1:6400(n=1). Individuals with titers ≥1:3200 showed clinical signs and symptoms such as fever and splenomegaly. The highest and lowest seropositivity were observed in the age groups of 5–9 and >15 years old, respectively. There were no significant difference between the rate of seropositivity in males and females.

Conclusion:

VL with a low prevalence circulates in some parts of Ilam province, particularly in the southern parts. Complementary studies should be needed to find animal reservoir hosts and vectors. Furthermore, health systems and physicians should pay particular attention to the disease.  相似文献   
56.

Background:

Haemonchosis has a negative effect on the farming industry throughout the world, especially in the tropic and sub-tropic countries. The present study was carried out to differentiate Haemonchus species from its main hosts in Iran, including sheep, goat and camel.

Methods:

The identification took place based on the morphometrics of the spicules and molecular characters. Two hundred seventy adult male nematodes were collected from the abomasums of different ruminants (90 samples from each animal) at the slaughterhouses from different localities in Iran. Samples were morphologically identified according to the spicules’ morphometric measurements. In the section on molecular study, 10 samples of each Haemonchus isolates were genetically examined. A simple PCR-restriction fragment length polymorphism (PCR-RFLP) assay of the second internal transcribed spacer of ribosomal DNA (ITS2-rDNA) were described to confirm the PCR results.

Results:

PCR-RFLP profile obtained from the restriction enzyme HPa1 in H. contortus and H. longistipes indicated 1 (278 bp) and 2 (113 and 135 bp) different fragments, respectively. The morphological parameters clearly distinguish H. contortus from H. longistipes. Moreover, regarding the ITS2-rDNA, sequences of 295 bp and 314 bp were obtained from H. contortus and H. longistipes, respectively.

Conclusion:

The genotypic results are in agreement with the phenotypic findings of both species.  相似文献   
57.
Phosphorus-containing compounds are one of the most important classes of organic compounds, which have wide applications in organic chemistry, medicinal chemistry, agricultural chemistry, and materials chemistry. In particular, organophosphorus compounds bearing a P(O)–C bond have attracted significant attention in recent decades due to their widespread biological and pharmacological activities. In this review, we will highlight the most important developments in the construction of P(O)–C bonds through decarboxylative C–P cross-coupling reactions. The literature has been surveyed from 2011 to May 2018.

Phosphorus-containing compounds are one of the most important classes of organic compounds, which have wide applications in organic chemistry, medicinal chemistry, agricultural chemistry, and materials chemistry.  相似文献   
58.
Clinical Rheumatology - Considering the pathologic significance of inflammation and oxidative stress in rheumatoid arthritis (RA) as well as the antioxidant, anti-inflammatory and hypolipidemic...  相似文献   
59.
Clinical Rheumatology - The clinical benefits of rituximab in systemic sclerosis (SSc) are still contentious. The present meta-analysis aimed to systematically assess rituximab’s safety and...  相似文献   
60.
Metabolic Brain Disease - Thymoquinone (Tq), an active compound of Nigella sativa, has been known for its anti-inflammatory, antioxidant, and neuroprotective characteristics. The present study is...  相似文献   
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