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991.
Twenty-two diurnally active, fair-skinned, male volunteers were repeatedly patch tested with 10, 15 and 20% lapyrium chloride (LC) and 0.3 and 0.5% sodium lauryl sulfate (SLS) for 5 consecutive days. A series of 5 patches containing SLS and LC were placed vertically once daily for 6 h on different sites of the scapula: paravertebral, lateral and medial. The sites of application were randomized over subjects for patch testing once a day per area at either 08%, 16% or 00%. Each patch was left in place 6 h; scoring of each site, using a 13-point scale, was done 2, 10 and 18 h after removal. The cutaneous reactivity varied in a statistically significant manner according to the time and area of patch application. For each day except the first, LC scores exhibited highest and lowest responses at 16% and 00%, respectively. For SLS, a statistically significant application-time difference in reactivity was detected only for the readings of day 2 when scores were highest at 00% and lowest at 16%. Intraregional variations in scapular reactivity were also exhibited. Strongest reactions to LC occurred in the center of each scapula; weakest reactions were elicited on either the lateral or paravertebral sites. For SLS, statistically significant intraregional differences in reactivity were detected only for the second day of patching, with strongest responses near the spinal column and weakest near the axilla.  相似文献   
992.
993.
994.
A collagenase dispersed cell suspension from PMSG-hCG primed immature rats responded to exogenously added hCG, cholera enteroxin, prolactin, and 8-Bromocyclic-AMP with increase in progesterone production in a dose dependent manner, and this stimulation was augmented by the plasma lipoprotein fractions hHDL and hLDL. The responsiveness to low doses of prolactin was not apparent when lipoprotein fractions were not included in the assay mixture. When the incubation mixture contained either LDL or HDL, the stimulatory effect of prolactin on progesterone production was evident at 5 and 10 micrograms prolactin/ml of the incubation mixture. Progesterone production, both basal and hormone stimulated, was maximum on day 7 of pseudopregnancy. Although the extent of hCG and prolactin stimulation of progesterone production and its potentiation by lipoprotein fractions was observed to be higher on days 3 and 5 than that seen on day 7, the net amount of progesterone produced was highest on day 7. The basal as well as hormone and lipoprotein stimulated progesterone production started to decline after day 7, reaching a nadir on day 14. These experiments show that prolactin is effective in stimulating progesterone production by rat luteal cells in vitro and that lipoprotein fractions, LDL and HDL further potentiate this response. This study further suggests that it is important to include LDL or HDL as a source of cholesterol for in vitro experiments in which the steroidogenic response of luteal cells to exogenous stimuli is tested.  相似文献   
995.
996.
In order to study the molecular basis of platelet interaction with collagen IV of the basement membrane separating the arterial endothelium from the underlying subendothelial connective tissue, the possibility of presence of platelet membrane protein with affinity to type IV collagen was examined by subjecting the platelet membrane extract to affinity chromatography on collagen IV-sepharose. Urea (4 M) eluate was found to contain a protein with an apparent mol. wt of 68 kDa. The radioiodinated protein was isolated and used to test its specificity. By dot blot assay on nitrocellulose disks and solid-phase assays, the 68 kDa protein was found to bind with high affinity to collagen IV. Lack of significant binding to fibronectin and laminin when compared to albumin control indicated its high specificity for collagen. The radioiodinated protein was inserted into egg yolk lecithin liposomes. While these liposomes attached to microtitre plates coated with collagen IV, there was no significant binding to fibronectin or laminin coated wells, suggesting the membrane associated character of the protein as well as its specificity for collagen. These results indicate that presence of a 68 kDa protein in platelet membrane which interacts with very high specificity to collagen IV.  相似文献   
997.
BackgroundAlthough bariatric surgery is well established as an effective treatment for patients with obesity and type 2 diabetes mellitus (T2DM), there exists reluctance to increase its availability for patients with severe T2DM. The aims of this study were to examine the impact of bariatric surgery on T2DM resolution in patients with obesity and T2DM requiring insulin (T2DM-Ins) using data from a national database and to develop a health economic model to evaluate the cost-effectiveness of surgery in this cohort when compared to best medical treatment (BMT).Methods and findingsClinical data from the National Bariatric Surgical Registry (NBSR), a comprehensive database of bariatric surgery in the United Kingdom, were extracted to analyse outcomes of patients with obesity and T2DM-Ins who underwent primary bariatric surgery between 2009 and 2017. Outcomes for this group were combined with data sourced from a comprehensive literature review in order to develop a state-transition microsimulation model to evaluate cost-effectiveness of bariatric surgery versus BMT for patients over a 5-year time horizon. The main outcome measure for the clinical study was insulin cessation at 1-year post-surgery: relative risks (RR) summarising predictive factors were determined, unadjusted, and after adjusting for variables including age, initial body mass index (BMI), duration of T2DM, and weight loss. Main outcome measures for the economic evaluation were total costs, total quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) at willingness-to-pay threshold of GBP£20,000.A total of 2,484 patients were eligible for inclusion, of which 1,847 had 1-year follow-up data (mean age of 51 years, mean initial BMI 47.2 kg/m2, and 64% female). 67% of patients no longer required insulin at 1-year postoperatively: these rates persisted for 4 years. Roux-en-Y gastric bypass (RYGB) was associated with a higher rate of insulin cessation (71.7%) than sleeve gastrectomy (SG; 64.5%; RR 0.92, confidence interval (CI) 0.86–0.99) and adjustable gastric band (AGB; 33.6%; RR 0.45, CI 0.34–0.60; p < 0.001). When adjusted for percentage total weight loss and demographic variables, insulin cessation following surgery was comparable for RYGB and SG (RR 0.97, CI 0.90–1.04), with AGB having the lowest cessation rates (RR 0.55, CI 0.40–0.74; p < 0.001). Over 5 years, bariatric surgery was cost saving compared to BMT (total cost GBP£22,057 versus GBP£26,286 respectively, incremental difference GBP£4,229). This was due to lower treatment costs as well as reduced diabetes-related complications costs and increased health benefits. Limitations of this study include loss to follow-up of patients within the NBSR dataset and that the time horizon for the economic analysis is limited to 5 years. In addition, the study reflects current medical and surgical treatment regimens for this cohort of patients, which may change.ConclusionsIn this study, we observed that in patients with obesity and T2DM-Ins, bariatric surgery was associated with high rates of postoperative cessation of insulin therapy, which is, in turn, a major driver of overall reductions in direct healthcare cost. Our findings suggest that a strategy utilising bariatric surgery for patients with obesity and T2DM-Ins is cost saving to the national healthcare provider (National Health Service (NHS)) over a 5-year time horizon.

Emma Rose McGlone and colleagues report the clinical and cost- effectiveness of bariatric surgery for patients with Type 2 diabetes.  相似文献   
998.
The present study was aimed to evaluate the radioprotective efficacy of dendrodoine analog (DA), an aminothiazole derivative against X-ray radiation-induced cellular damage in cultured human peripheral blood lymphocytes. Different concentrations of DA (2, 4, 6, 8, 10 μg/ml or 6.15, 12.29, 18.44, 24.59, 30.73 μM) were pre-incubated with lymphocytes for 30 min prior to irradiation [4 Gy] and the micronuclei (MN) scoring and comet assay were performed to fix the effective concentration of DA against 4 Gy irradiation-induced cellular damage. The results indicated that among all the concentrations, 6 μg/ml concentration of DA showed optimum protection by effectively decreasing the MN frequencies and comet attributes. Based on the above results, 6 μg/ml concentration of DA was fixed as the effective dose to further investigate its radioprotective efficacy. This was carried out by pre-incubating the lymphocytes with 6 μg/ml concentration of DA followed by exposure of the lymphocytes to different doses (1, 2, 3 and 4 Gy) of radiation and investigating the radiation-induced genetic damage (MN, comet assay, DNA fragmentation assay) and biochemical changes (changes in the level of enzymic and non-enzymic antioxidants, lipid peroxidation). The results indicated a dose-dependent increase in both genetic damage and thiobarbituric acid reactive substances (TBARS), accompanied by a significant decrease in the antioxidant status in the irradiated groups compared to DA treated groups which modulated the toxic effects through its antioxidant potential. Thus the current study shows DA to be an effective radioprotector against X-ray radiation induced in vitro cellular damage in lymphocytes.  相似文献   
999.
The effect of carnitine on free fatty acid, malondialdehyde, taurine and glutathione levels in myocardium was studied in rats administered isoproterenol to induce a stress in the myocardium resulting in myocardial ischaemia. Carnitine decreased the levels of free fatty acid and malondialdehyde (an index of lipid peroxidation) when compared to control rats given isoproterenol alone. Taurine and glutathione also registered a fall in the carnitine treated animals when compared to rats treated with isoproterenol alone. The results indicate that carnitine by decreasing the levels of these parameters helps the myocardium to survive from the stress induced by isoproterenol.  相似文献   
1000.
Light and electron microscopy of the glandular epithelium of intersegmental membranes between sternites three and seven and tergites two and eight of various age groups of Nauphoeta cinerea male adults and one age group of female adults discloses differences in the epithelia of the intersternite and intertergite. The intersternal epithelium appears thicker, more glandular, and stratified. Altogether, seven cell types are recognizable, six in the male and two in the female. They are designated as types 1, 2a, 2b, 2c, 3, 4, and 5. Of these, types 1, 2a, 3, and 4 are recognizable on the sternum; types 1, 2b, and 5 on the tergum of the mature male integuments. Types 1 and 2c are found on the sternum of mature female. The cell types undergo morphological differentiation after adult emergence and show different stages of secretory activity. Type 1 are squamous cuticle-secreting cells; type 2a, 2b, and 2c are columnar-glandular and contain electron-transparent secretory vesicles of various sizes, which increase greatly in number and size in the 5-day-old adult males when the glands are most active. The vesicular size and number also differ between types 2a, 2b, and 2c cells of the same age group. The vesicles are assumed to be derived from smooth endoplasmic reticulum. The type 2 gland cells are also provided with a secretory end apparatus lined by cuticle and bordered by microvilli through which the secretion is believed to be released by exocytosis. The end apparatus leads into a cuticular ductule that opens to the surface of the cuticle as a cup-shaped receptacle, which is more conspicuous in the male intersternite. In the active gland cells, the mitochondria near the end apparatus are swollen and vacuolated. Type 3 cells are seen only on the intersternum and are believed to secrete the cuticular ductule that proceeds from the end apparatus. Type 4 cells are also recognizable only on the male intersternum and contain closely packed, electron-dense bodies, which are most numerous in mature (5-day-old) males. Type 5 cells with their dense cytoplasm are located basally in the intertergal epithelium. The functional significance of type 4 and 5 cells in the males and type 2c cells in the female is not clear. On the basis of differences in morphology, pheromone activity, and sexual behavior, it is suggested that the pheromones secreted by the intersternal and intertergal glands in the male are different, the former secreting a seducin that attracts the female to the male and the latter an “aphrodisiac” acting as a contact pheromone important in accomplishing mating.  相似文献   
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