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41.
Summary: Hydrophobically modified poly(acrylic acid) was synthesized using 3‐pentadecylcyclohexylamine (3‐PDCA), which was in turn synthesized from 3‐pentadecylphenol, one of the components of cashew‐nut shell liquid (CNSL), a renewable resource material. 1H NMR spectra confirmed the incorporation of 3‐PDCA onto PAA and a series of HMPs with three different molar concentrations, viz ? 3, 5 and 7 mol‐% of 3‐PDCA, were synthesized. An increase in viscosity with increasing hydrophobic content was observed by rheological measurements. The critical association concentrations were determined using an Ubbelohde viscometer and a controlled stress rheometer. The stability of HMPs towards temperature and shear was studied. Rheological measurements showed that there was a steady increase in viscosity with increase in hydrophobe content due to the formation of reversible networks. These polymers exhibited gel‐like behavior at low concentrations (≥2 wt.‐%) with an apparent yield stress (ca. 10 Pa) and showed shear thinning properties (non‐Newtonian). However, below a critical concentration, c [η], they showed Newtonian behavior.

ηsp of unmodified and modified PAA‐Na at various polymer concentrations.  相似文献   

42.
43.
High level of plasma creatinine occurs in renal insufficiency, uremia, and other diseases. At present lowering of this metabolite is done by using dialysis and other techniques. In this article, we report the use of artificial cells microencapsulated genetically engineered E. coli DH5 cells for lowering plasma creatinine in-vitro and in-vivo. Result shows that artificial cells were able to lower plasma creatinine in-vitro from 21.80 +/- 1.10 mg/dl to 21.80 +/- 1.10 mg/dl in 60 minutes and to 19.34 +/- 0.60 mg/dl in 3 hours. Result also shows that when given orally on a daily basis, artificial cells microencapsulated genetically engineered E. coli DH5 cells were also able to lower plasma creatinine in rats.  相似文献   
44.
There is a deficit of literature regarding the association between nickel allergy–induced symptoms and implanted devices. This report describes a case of nickel allergy causing debilitating migraine-like symptoms, failing to resolve with medical therapy, requiring surgical removal of the device and repair of the defect.  相似文献   
45.

Textile dyes are becoming a growing threat to the environment. This report presents the findings of the study on the toxicity of the textile dye Alizarin Red S on two freshwater microalgae. The acute toxicity assay revealed that 96-h EC50 values of Chlorella vulgaris and Spirulina platensis were 29.81 mg/L and 18.94 mg/L respectively. The pigments chlorophyll-a, b and carotenoids in C. vulgaris on 96-h exposure to the dye were 2.91, 3.29 and 3.01 times lower in analogy to control whereas Spirulina platensis showed 2.89and 2.56 fold decrease in chlorophyll-a and carotenoid content than control. After the test period of 96-h with dye, the protein content of C. vulgaris and S. platensis were 2.33 and 1.77 times lower compared to the control. The growth inhibition rate, pigment as well as the protein content declined in compliance with the rise in dye concentration, which anticipate paradigm about the toxic effects of the textile dye.

  相似文献   
46.
The study aim was to examine the effect on birth spacing of a prior female child's birth. The study site was a rural health center under observation by staff from the Dayanand Medical College in Ludhiana, India. The sample included 73 pregnant women who were grouped by the sex of the preceding child. The results showed that the average birth interval was significantly shorter for women with a preceding birth of a female child. The average interval in weeks was 90.73 weeks + or - 54.46 weeks for the 41 women who had a prior girl child compared to 133.68 weeks for the male child. When the female child was at a parity of one the birth interval averaged 73.36 weeks, compared to 137.2 weeks for a prior parity of one male child. At parity of two, the average birth interval was 106.2 for a prior girl child and 144.38 for a prior male child. At a parity of three, the average birth interval was 88.22 weeks for a prior girl child and 96.5 weeks for a prior male child. At a parity of four, the average birth interval was 87.66 weeks for a prior girl child and 46.0 weeks for a prior male child. The significant effect of having a prior girl child was evident only at a parity of one. The intervals at a parity of two and three were shorter for girls but not significantly different. The recommendation was that young women and women with low parity be targeted for family planning in order to lengthen the birth interval, regardless of the desire for sons.  相似文献   
47.
48.
Prakash J 《Renal failure》1999,21(6):707-711
Acute renal failure (ARF) complicating epidemic dropsy is reported in three patients. In this study, ARF resolved in two patients over a period of 4-6 weeks with conservative and dialytic support. One patient died of refractory heart failure. To the best of our knowledge ARF in association with epidemic dropsy has not been reported before in the literature from India.  相似文献   
49.
50.
Prakash A  Markham A 《Drugs》1999,57(3):383-408
Oral delayed-release mesalazine is an enteric-coated formulation which releases mesalazine in the terminal ileum and colon. Up to 74% of patients with mild to moderately active ulcerative colitis experience endoscopic or symptomatic improvement (including remission) or both when treated with oral delayed-release mesalazine 2.4 to 4.8 g/day. There is a trend towards a better response in patients receiving higher daily dosages of oral delayed-release mesalazine, especially in patients with active distal disease. In patients with left-sided ulcerative colitis, oral balsalazide 6.75 g/day appears to be more effective than oral delayed-release mesalazine 2.4 g/day, but a higher dosage of oral delayed-release mesalazine 4.8 g/day may provide additional benefit in these patients. Oral delayed-release mesalazine 0.8 to 4.4 g/day appears to be as effective as sulfasalazine 2 to 4 g/day, prolonged-release mesalazine 1.5 g/day or balsalazide 3 g/day in maintaining remission in patients with ulcerative colitis. The optimal dosage of oral delayed-release mesalazine for the maintenance of remission is unclear. However, oral delayed-release mesalazine 1.6 g/day with rectal mesalazine 4g, administered twice weekly, was more effective than oral drug alone in maintaining remission in patients at high risk of relapse. In patients with left-sided or distal disease oral olsalazine 1 g/day appeared to be superior to oral delayed-release mesalazine 1.2 g/day for maintenance of symptomatic remission. Limited data in patients with Crohn's disease have shown oral delayed-release mesalazine 0.4 to 4.8 g/day to be an effective therapy for active disease (remission in up to 45% of patients) and for quiescent disease (relapse in 34% of recipients over a duration of up to 12 months). Preliminary data indicate that oral delayed-release mesalazine 2.4 g/day is effective in preventing postoperative recurrence of Crohn's disease. Oral delayed-release mesalazine is effective and well tolerated in sulfasalazine-intolerant patients with ulcerative colitis or Crohn's disease. CONCLUSIONS: Oral delayed-release mesalazine is effective in patients with mild to moderately active or quiescent ulcerative colitis. Available data suggest that patients with left-sided or distal ulcerative colitis are likely to require higher daily dosages of oral delayed-release mesalazine or supplementation with rectal mesalazine. Oral delayed-release mesalazine also appears to be effective in active and quiescent Crohn's disease. The drug is well tolerated and it appears to be effective in sulfasalazine-intolerant patients.  相似文献   
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