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91.
Effect of calcium ion on the structure of native bovine casein micelles   总被引:3,自引:0,他引:3  
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92.
The biosynthesis of crotsparine, crotsparinine and sparsiflorine in Croton sparsiflorus has been studied using racemic [Ar-3H]-coclaurine, isococlaurine and norcoclaurine. Tyrosine and coclaurine are shown to be precursors of all three alkaloids.  相似文献   
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Single institution and population-based studies highlight that infectious complications following transrectal ultrasound guided prostate needle biopsy (TRUS PNB) are increasing. Such infections are largely attributable to quinolone resistant microorganisms which colonize the rectal vault and are translocated into the bloodstream during the biopsy procedure. A povidone iodine rectal preparation (PIRP) at time of biopsy is a simple, reproducible method to reduce rectal microorganism colony counts and therefore resultant infections following TRUS PNB.All patients are administered three days of oral antibiotic therapy prior to biopsy. The PIRP technique involves initially positioning the patient in the standard manner for a TRUS PNB. Following digital rectal examination, 15 ml of a 10% solution of commercially available povidone iodine is mixed with 5 ml of 1% lidocaine jelly to create slurry. A 4 cm x 4 cm sterile gauze is soaked in this slurry and then inserted into the rectal vault for 2 min after which it is removed. Thereafter, a disposable cotton gynecologic swab is used to paint both the perianal area and the rectal vault to a distance of 3 cm from the anus. The povidone iodine solution is then allowed to dry for 2 - 3 min prior to proceeding with standard transrectal ultrasonography and subsequent biopsy.This PIRP technique has been in practice at our institution since March of 2012 with an associated reduction of post-biopsy infections from 4.3% to 0.6% (p = 0.02). The principal advantage of this prophylaxis regimen is its simplicity and reproducibility with use of an easily available, inexpensive agent to reduce infections. Furthermore, the technique avoids exposing patients to additional systemic antibiotics with potential further propagation of multi-drug resistant organisms. Usage of PIRP at TRUS PNB, however, is not applicable for patients with iodine or shellfish allergies.  相似文献   
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BackgroundXpert MTB/RIF, the first automated molecular test for tuberculosis, is transforming the diagnostic landscape in high-burden settings. This study assessed the impact of up-front Xpert MTB/RIF testing on detection of pulmonary tuberculosis (PTB) and rifampicin-resistant PTB (DR-TB) cases in India.MethodsThis demonstration study was implemented in 18 sub-district level TB programme units (TUs) in India in diverse geographic and demographic settings covering a population of 8.8 million. A baseline phase in 14 TUs captured programmatic baseline data, and an intervention phase in 18 TUs had Xpert MTB/RIF offered to all presumptive TB patients. We estimated changes in detection of TB and DR-TB, the former using binomial regression models to adjust for clustering and covariates.ResultsIn the 14 study TUs, which participated in both phases, 10,675 and 70,556 presumptive TB patients were enrolled in the baseline and intervention phase, respectively, and 1,532 (14.4%) and 14,299 (20.3%) bacteriologically confirmed PTB cases were detected. The implementation of Xpert MTB/RIF was associated with increases in both notification rates of bacteriologically confirmed TB cases (adjusted incidence rate ratio [aIRR] 1.39; CI 1.18-1.64), and proportion of bacteriological confirmed TB cases among presumptive TB cases (adjusted risk ratio (aRR) 1.33; CI 1.6-1.52). Compared with the baseline strategy of selective drug-susceptibility testing only for PTB cases at high risk of drug-resistant TB, Xpert MTB/RIF implementation increased rifampicin resistant TB case detection by over fivefold. Among, 2765 rifampicin resistance cases detected, 1055 were retested with conventional drug susceptibility testing (DST). Positive predictive value (PPV) of rifampicin resistance detected by Xpert MTB/RIF was 94.7% (CI 91.3-98.1), in comparison to conventional DST.ConclusionIntroduction of Xpert MTB/RIF as initial diagnostic test for TB in public health facilities significantly increased case-notification rates of all bacteriologically confirmed TB by 39% and rifampicin-resistant TB case notification by fivefold.  相似文献   
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Restricted supply of micronutrients is a common constraint for plant growth worldwide, especially in organic farming systems where nutrients supply to crops mostly depends on the mineralization of native soil organic matter, decomposition of applied manures and crop residues. A laboratory incubation study was therefore conducted to investigate the potential release of copper (Cu), manganese (Mn) and zinc (Zn) from the rock mineral flour (RMF) and city waste compost (CWC) as compared to inorganic micronutrient fertilizers for 140 days. Release of the micronutrients from RMF and CWC showed different trends. The results showed that about 4.6% of Cu added as RMF was released irrespective of the quantity of the RMF applied. However, Cu release from CWC increased from 0.7 to 3.5% as the amount of compost added was increased. Copper recovery from copper sulphate was 98%. Manganese release from RMF decreased from 114 to 103% as the RMF level was increased, while the corresponding decrease in Mn release from CWC was from 14 to ?3%. Manganese recovery from manganese sulphate was 100%. Zinc release from RMF increased from 5.8?15.5%, with an increase in the amount of RMF applied, while no Zn was released from CWC. Recovery of Zn from zinc sulphate was 98%. These results show that RMF and CWC could be used to meet Cu, Mn and Zn requirements of organically grown cereals. The results of the investigation have general applicability in organic farming.  相似文献   
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Background

Little information exists regarding the burden of HIV among tuberculosis patients in India, and no population-based surveys have been previously reported. A community-based HIV prevalence survey was conducted among tuberculosis patients treated by the national tuberculosis control programme to evaluate the HIV prevalence among tuberculosis patients in India.

Methodology/Principal Findings

Fifteen districts (total population: 40.2 million) across 8 states were stratified by HIV prevalence in antenatal clinic HIV surveillance sites and randomly selected. From December 2006 to May 2007, remnant serum was collected from patients'' clinical specimens taken after 2 months of anti-tuberculosis treatment and subjected to anonymous, unlinked HIV testing. Specimens were obtained and successfully tested for 5,995 (73%) of 8,217 tuberculosis patients eligible for the survey. HIV prevalence ranged widely among the 15 surveyed districts, from 1% in Koch Bihar, West Bengal, to 13.8% in Guntur, Andhra Pradesh. HIV infection was 1.3 times more likely among male TB patients than among female patients. Relative to smear-positive tuberculosis, HIV infection was 1.4 times more likely among smear-negative patients and 1.3 times more likely among extrapulmonary patients. In 4 higher-HIV prevalence districts, which had been previously surveyed in 2005–2006, no significant change in HIV prevalence was detected.

Conclusions

The burden of HIV among tuberculosis patients varies widely in India. Programme efforts to implement comprehensive TB-HIV services should be targeted to areas with the highest HIV burden. Surveillance through routine reporting or special surveys is necessary to detect areas requiring intensification of TB-HIV collaborative activities.  相似文献   
100.
Epstein-Barr virus (EBV) causes EBV-associated lymphoproliferative diseases in patients with profound immune suppression. Most of these diseases are life-threatening and the prognosis of AIDS-associated lymphomas is extremely unfavorable. Polyclonal expansion of virus infected B-cell predisposes them to transformation. We investigated the possibility of nuclear factor kappa B (NF-kappaB) inhibition by dehydroxymethylepoxyquinomicin (DHMEQ) for the treatment and prevention of EBV-associated lymphoproliferative diseases. We examined the effect of DHMEQ on apoptosis induction in four EBV-transformed lymphoblastoid cell lines as well as peripheral blood mononuclear cells infected with EBV under immunosuppressed condition. DHMEQ inhibits NF-kappaB activation in EBV-transformed lymphoblastoid cell lines and induces apoptosis by activation of mitochondrial and membranous pathways. Using an in vivo NOD/SCIDgammac mouse model, we showed that DHMEQ has a potent inhibitory effect on the growth of lymphoblastoid cells. In addition, DHMEQ selectively purges EBV-infected cells expressing latent membrane protein (LMP) 1 from peripheral blood mononuclear cells and inhibits the outgrowth of lymphoblastoid cells. These results suggest that NF-kappaB is a molecular target for the treatment and prevention of EBV-associated lymphoproliferative diseases. As a potent NF-kappaB inhibitor, DHMEQ is a potential compound for applying this strategy in clinical medicine.  相似文献   
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