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541.
542.
AR Logesh KA Thillaimaharani K Sharmila M Kalaiselvam SM Raffi 《Asian Pacific Journal of Tropical Biomedicine》2012,2(2):140-143
Objective
To screen the chitosan producing ability of endolichenic fungi and its antibacterial activity.Methods
Lichen collected from mangroves was screened for endophytes and the chitosan producing ability of endolichenic fungi by submerged fermentation was also determined. Antibacterial activity was carried out against different pathogens.Results
Totally 4 different groups of fungi were isolated from the lichen Roccella montagnei. Among the four genera, Aspergillus niger (A. niger) is potential to produce chitosan (1.3 g/L) on the twelfth day of incubation. Glucose plays an important role in the productivity of chitosan and the yield was maximum at 10% (1.93 g/L). Antibacterial activity revealed that Vibrio cholerae was sensitive to chitosan followed by Escherichia coli.Conclusions
In conclusion, our findings suggest that A. niger is a potential candidate to produce more chitosan than the other strains and glucose plays an important role in the production of chitosan which proves to have a good antibacterial activity. 相似文献543.
AR Finch KR Sedgley SP Armstrong CJ Caunt CA McArdle 《British journal of pharmacology》2010,159(4):751-760
Gonadotrophin-releasing hormone (GnRH) is a neuropeptide that mediates central control of reproduction by stimulating gonadotrophin secretion from the pituitary. It acts via 7 transmembrane region (7TM) receptors that lack C-terminal tails, regions that for many 7TM receptors, are necessary for agonist-induced phosphorylation and arrestin binding as well as arrestin-dependent desensitization, internalization and signalling. Recent work has revealed that human GnRH receptors (GnRHR) are poorly expressed at the cell surface. This apparently reflects inefficient exit from the endoplasmic reticulum, which is thought to be increased by pharmacological chaperones (non-peptide GnRHR antagonists that increase cell surface GnRHR expression) or reduced by point mutations that further impair GnRHR trafficking and thereby cause infertility. Here, we review recent work in this field, with emphasis on the use of semi-automated imaging to interrogate compartmentalization and trafficking of these unique 7TM receptors.This article is part of a themed section on Imaging in Pharmacology. To view the editorial for this themed section visit http://dx.doi.org/10.1111/j.1476-5381.2010.00685.x 相似文献
544.
545.
Bernardi F; Petraglia F; Seppala M; Spinetti A; Bertolini S; Ferdeghini M; Genazzani AR 《Human reproduction (Oxford, England)》1998,13(2):279-284
The altered function of the somatotropic axis observed in perimenopause may
underlie the changes in body weight and fat distribution. The aim of the
present study was to evaluate, in pre-menopausal and post- menopausal women
with body mass index (BMI) > or = or <25, the basal plasma levels of
growth hormone (GH), insulin-like growth factor (IGF)- I and -II, IGF
binding protein (IGFBP)-1 and -3, and the response of GH and IGFBP-1 and -3
to GH releasing hormone (GHRH) and GHRH plus arginine tests. GH and IGF-I
basal concentrations were significantly higher in pre-menopausal than in
post-menopausal women, while IGF-II, IGFBP-1 and IGFBP-3 concentrations did
not vary significantly. IGFBP-1, but not IGFBP-3, concentrations were
higher in lean than in obese patients. Insulin concentrations were
significantly higher in obese patients, while no differences were observed
between pre-menopausal and post-menopausal women. In all subjects, GH
concentrations increased significantly during GHRH test; pre-menopausal and
lean women showed a higher response compared to post-menopausal and obese
women. The GHRH plus arginine test stimulated GH response in all women,
irrespective of age and BMI. IGFBP-1 and -3 concentrations did not vary in
response to GHRH or GHRH plus arginine tests. The somatotropic axis
undergoes modifications in post-menopausal women, apparently not involving
IGFBP- 1 and -3. Arginine infusion restores the response of GH to GHRH, in
both post-menopausal and obese subjects. A somatostatinergic hyperactivity
at the climateric period may underlie the changes both in body weight and
somatotropic axis.
相似文献
546.
Computed tomography in Graves' ophthalmopathy 总被引:2,自引:0,他引:2
547.
ERDAL YILMAZ ERTAN BATISLAM ONDER BOZDOGAN HALL BAAR M MURAD BAAR 《International journal of urology》2004,11(3):182-183
Torsion of an epididymal cyst is a very rare condition. We present a case of torsion of an epididymal cyst in a 13-year-old boy. The patient presented with acute scrotal pain. Scrotal ultrasonography showed a 38 x 35 x 30 mm fluid-filled mass within the caput of the left epididymis. Histologically, the cells of the epididymal duct were necrotic. To our knowledge, this is the second case report in the literature. 相似文献
548.
Solitary metastasis of renal cell carcinoma to the parotid gland 10 years after radical nephrectomy 总被引:1,自引:0,他引:1
ÇAATAY GÖÜ ÖZCAN KILIÇ ÖZLEM TULUNAY ÖZDEN TULUNAY YAAR BEDÜK 《International journal of urology》2004,11(10):894-896
Abstract Renal cell carcinoma metastasis to the parotid gland after tumor nephrectomy is extremely rare. We report a case of solitary parotid metastasis from clear cell renal cell carcinoma in a 59‐year‐old woman, who presented 10 years after primary treatment. To our knowledge this is the first case in the published literature presenting with solitary parotid metastasis after such a long time. Superficial parotidectomy with preservation of the facial nerve was performed. One year after, the patient developed contralateral multiple kidney tumors and underwent left radical nephrectomy. She is currently on a dialysis program and no additional metastasis has been observed for 18 months. 相似文献
549.
550.
The presurgical management with erythrocytapheresis of a patient with a high-oxygen-affinity, unstable Hb variant (Hb Bryn Mawr) 总被引:1,自引:0,他引:1
PJ Larson ; DF Friedman ; MP Reilly ; AC Kattamis ; T Asakura ; P Fortina ; AR Cohen ; HC Kim ; CS Manno 《Transfusion》1997,37(7):703-707
BACKGROUND: Hemoglobin (Hb) Bryn Mawr is an unstable Hb variant resulting in congenital hemolytic anemia. This variant Hb also has an increased affinity for oxygen. The perioperative transfusion management of this disorder is described, and the first genomic analysis of this Hb variant is given. CASE REPORT: An 11-year-old boy, heterozygous for Hb Bryn Mawr, was referred for cholecystectomy. Sequence analysis of genomic DNA confirmed that the patients was heterozygous for a T–>C transition in the codon for amino acid 85, causing a substitution of serine for phenylalanine in the beta-globin chain. On the basis of whole-blood O2 dissociation studies, projected tissue O2 delivery would have been suboptimal during general anesthesia; therefore, a partial red cell exchange transfusion was performed to lower variant Hb and prevent tissue hypoxia during surgery. The red cell mass to be exchanged (50%) was determined from the calculated increase in O2 delivery capacity required to maintain an O2 extraction of 4 to 5 mL of O2 per dL of whole blood. The p50 of whole blood from the patients immediately after the exchange transfusion was 16.0 torr. At the time of surgery, the p50 was normal (25.9 torr). The patient's whole blood 2,3 DPG levels were 4.70 mmol per mL of red cells (before transfusion) (normal range=4.8 +/? 0.3 mmol/mL red cells), 4.07 mmol per mL of red cells (immediately after transfusion), and 4.55 mmol per mL of red cells (48 hours after transfusion). CONCLUSION: This patient with Hb Bryn Mawr was prepared for surgery with a partial exchange transfusion to prevent tissue hypoxia during anesthesia. Decreased 2,3 DPG levels immediately after transfusion resulted in increased O2 affinity of whole blood; however, 48 hours after exchange transfusion, a normal p50 (due to both removal of variant Hb and regeneration of 2,3, DPG) was observed. Partial exchange transfusion is useful in the preoperative management of patients with Hb variants characterized by increased O2 affinity. 相似文献