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排序方式: 共有513条查询结果,搜索用时 15 毫秒
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Genotype-phenotype correlation for nucleotide substitutions in the IgII- IgIII linker of FGFR2 总被引:6,自引:3,他引:3
6.
Neurons containing serotonin (5-HT), a potent anorexic agent, come into contact with neuropeptide Y-ergic neurons, that project from the arcuate nucleus (ARC) to the paraventricular nucleus (PVN). NPY powerfully stimulates feeding and induces obesity when injected repeatedly into the PVN. We hypothesize that 5-HT tonically inhibits the ARC-PVN neurons and that balance between the two systems determines feeding and energy homeostasis. This study aimed to determine whether central injection of the 5-HT synthesis inhibitor p-chlorophenylalanine (pCPA), which increases feeding, increased hypothalamic NPY and NPY mRNA levels. pCPA (10 mg/kg in 3 μl) was administered into the third ventricle either as a single injection (n = 8) or daily for 7 days (n = 8). Control rats received a similar injection of saline. pCPA significantly increased food intake compared with controls after both single and repeated injections (P < 0.05). NPY levels were measured by radioimmunoassay in microdissected hypothalamic extracts. NPY levels in the acutely treated group were significantly increased in the paraventricular nucleus (PVN; by 41%,P = 0.01), anterior hypothalamic area (AHA; by 34%,P < 0.01) and lateral hypothalamic area (LHA; by 41%,P < 0.02). In the 7-day-treated group, NPY levels were also increased in the same areas, i.e. PVN (by 24%,P < 0.01), AHA (by 30%,P < 0.01) and LHA (by 38%,P = 0.01). There were no significant changes in the ARC or any other region or in hypothalamic NPY mRNA levels. pCPA administration increased NPY levels in several regions notably the PVN. This is a major site of NPY release, where NPY injection induces feeding. We suggest that the hyperphagia induced by pCPA is mediated by increased NPY levels and secretion in the PVN. This is further evidence for interactions between NPY and 5-HT in the control of energy homeostasis. 相似文献
7.
M S Dryden M Wilkinson M Redman M R Millar 《The British journal of general practice》1994,44(380):114-117
BACKGROUND. Chlamydia trachomatis is frequently overlooked as a cause of dysuria and urinary frequency in general practice patients. AIM. This study set out to determine the impact of performing chlamydial antigen detection on sterile pyuria samples from patients aged 16-65 years and which were submitted to a hospital microbiology laboratory by general practitioners in the Winchester health district for routine microbiological investigations. METHOD. Chlamydial antigen detection was performed by enzyme immunoassay and direct immunofluorescence. The cost of performing the test was estimated. In the first year of the study (1991) questionnaires were sent to general practitioners whose patients had a positive test result. RESULTS. A total of 1025 samples of sterile pyuria were received at the laboratory between January 1991 and March 1993. Chlamydial antigen was detected in 54 samples (5%); 22 men and 32 women aged between 16 and 57 years (mean 25 years). The detection rate was highest in the 16-20 years age group (22% of men had a positive sample and 7% of women). Completed questionnaires from 27 general practitioners revealed that 59% of their patients were referred to the genitourinary clinic for treatment and contact tracing. The others were treated by the general practitioner. The cost of the screening programme per cure in this population was estimated to be 246 pounds. CONCLUSION. C trachomatis is a significant pathogen which may go unrecognized and untreated. The cost, medically and financially, of screening for this pathogen and treating infected patients and contacts is likely to be less than ignoring it, particularly if screening is confined to the 16-30 years age group. General practitioners should consider the diagnosis of chlamydial infection in young adult patients with sterile pyuria, and microbiology laboratories should screen sterile pyuria samples for chlamydial antigen. 相似文献
8.
Rust MK Waggoner M Hinkle NC Mencke N Hansen O Vaughn M Dryden MW Payne P Blagburn BL Jacobs DE Bach T Bledsoe D Hopkins T Mehlhorn H Denholm I 《Journal of medical entomology》2002,39(4):671-674
Strategies for controlling cat fleas, Ctenocephalidesfelisfelis (Bouché), have undergone dramatic changes in the past 5 yr. With the advent of on-animal treatments with residual activity the potential for the development of insecticide resistance increases. A larval bioassay was developed to determine the baseline susceptibility of field-collected strains of cat fleas to imidacloprid. All four laboratory strains tested showed a similar level of susceptibility to imidacloprid. Advantages of this bioassay are that smaller numbers of fleas are required because flea eggs are collected for the test. Insect growth regulators and other novel insecticides can also be evaluated. Using a discriminating dose, the detection of reduced susceptibility in field strains can be determined with as few as 40 eggs. 相似文献
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C Camenzuli AN DiMarco KE Isaacs Y Grant J Jackson A Alsafi C Harvey TD Barwick N Tolley FF Palazzo 《Annals of the Royal College of Surgeons of England》2021,103(1):29
IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes. 相似文献
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A novel immunization method to induce cytotoxic T-lymphocyte responses (CTL) against plasmid-encoded herpes simplex virus type-1 glycoprotein D 总被引:2,自引:0,他引:2
Cruz PE Khalil PL Dryden TD Chiou HC Fink PS Berberich SJ Bigley NJ 《Vaccine》1999,17(9-10):1091-1099
DNA molecules complexed with an asialoglycoprotein-polycation conjugate, consisting of asialoorosomucoid (ASOR) coupled to poly-L-lysine, can enter hepatocytes which bear receptors for ASOR. We used this receptor-mediated DNA delivery system to deliver plasmid DNA encoding glycoprotein D (gD) of herpes simplex virus type 1 to ASOR-positive cells. Maximum expression of gD protein was seen at 3 days after injection of this preparation in approximately 13% of cells from BALB/c mice [hepatocytes from mice injected intravenously (i.v.) or peritoneal exudate cells from mice injected intraperitoneally (i.p.)]. In comparison with mice injected with either the plasmid vector alone or the gD-containing plasmid uncomplexed to ASOR, mice immunized with gD-containing plasmid complexed with ASOR-poly-L-lysine induced marked antigen-specific CTL responses. BALB/c mice immunized with gD-DNA developed a T-cell-mediated CTL response against target cells expressing gD and MHC class II glycoproteins, but not against cells expressing only gD and MHC class I molecules. In C3H mice, gD-DNA induced a T-cell-mediated CTL response against target cells expressing gD and class I MHC molecules. Serum anti-gD antibody in low titers were produced in both strains of mice. DNA complexed with ASOR-poly-L-lysine induced CTL responses in mice. 相似文献