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991.
A questionnaire was sent to all centres in the UK involved in cryopreservation of semen from men with malignant disease. Details were requested of samples stored from 1977 to 1987 and of successful use of this sperm in subsequently achieving pregnancy. Twenty-two centres are involved and have stored specimens from 2,219 men. There has been a three-fold increase in referrals in the past five years. Three regions in England have no service. Twenty-seven pregnancies (21 live births) have been achieved in 22 couples. Laboratories are poorly funded, making adequate record keeping and audit of the service difficult. 相似文献
992.
H S Hosker D C Lindsay F Game A A Codd G Dale C O Record 《Postgraduate medical journal》1988,64(757):854-855
The incidence and types of viral hepatitis in the city of Newcastle upon Tyne have been studied by serological analysis of (a) all blood samples sent to the virological laboratory for hepatitis testing and (b) all blood samples sent by general practitioners to the biochemical laboratory for liver function testing. The annual detection rate of acute viral hepatitis was found to be 31.5 cases/100,000 population, of which 9.1 were hepatitis B. Only three sporadic cases of non-A non-B hepatitis were identified. The incidence of hepatitis is at least four-fold greater than suggested by notification rates and may be substantially higher as general practitioners rarely requested laboratory confirmation of household contacts of index cases. 相似文献
993.
Lindsay Aitkin John Nelson Moyra Farrington Sue Swann 《The Journal of comparative neurology》1994,343(4):532-541
As a part of a project concerning the development of hearing, some features of the morphological development of the inferior colliculus were studied in a marsuglial, the Northern quall or native cat (Dasyurus hallucatus). Marsuglials are of particular interest in developmental studies because much embryonic development occurs outside the uterus, in the pouch. Nissl-stained material was prepared from pouch-young at various ages between 11 and 81 days, and for a number of adults. Four pouch-young were injected with tritiated thymidine and killed later during pouch life. The inferior colliculus is first recognizable in pouch-young aged 23 days, when it is bordered by a cell-sparse ring of tissue. By this time, the labelling patterns following injections of tritiated thymidine made on days 7–9 suggest that migration of cells to the inferior colliculus from the ventricular germinal zone has been largely completed. At 81 days, close to the time when the young move out of the pouch, the adult cytoarchitecture—a central nucleus flanked by dorsal and lateral cortical regions—is clear. Cell areas expand monotonically as a function of age. The period of days 45–50 is associated with a large expansion of cell volume and a concomitant decrease in packing density. It is likely that functional connections are forming during this period, which may herald the onset of hearing in the quall. Total cell numbers increase to a peak at day 36, fall to a minimum at day 50, and rise again to the adult value. The second increase is likely to be a phase of glial proliferation, in part associated with the onset of myelination. This increase correlates with departure of the young from the pouch. © 1994 Wiley-Liss, Inc. 相似文献
994.
995.
Ullrich Wüllner Peyman Pakzaban Anna-Lisa Brownell Philippe Hantraye Lindsay Burns Timothy Shoup David Elmaleh Andrew J. Petto Roger D. Spealman Gordon L. Brownell Ole Isacson 《Experimental neurology》1994,126(2)
We studied the time course of dopamine (DA) terminal loss in three macaca fascicularis injected with MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) intravenously every 10-14 days for up to 389 days. Striatal DA terminal loss was monitored in vivo by positron emission tomography using 11 C-CFT (WIN 35,428), a cocaine derivative that labels the DA transporter. The 11C-CFT uptake rate constant in the striatum of MPTP-treated monkeys decreased exponentially over time, with the putamen significantly more affected than the caudate. Spontaneous locomotor activity decreased in parallel with the decline of the 11C-CFT uptake rate; however, overt parkinsonian signs appeared only after the 11C-CFT uptake rate had declined to about 30% of the pretreatment values. We conclude that a long-term intermittent mode of administration of MPTP can lead to a pattern of terminal loss that closely resembles idiopathic Parkinson disease. 相似文献
996.
997.
J N Bradbeer J M Zanelli P C Lindsay J Pearson J Reeve 《Journal of bone and mineral research》1992,7(8):905-912
It is not feasible to use in vivo tetracycline double labeling to study bone formation in biopsies taken during the emergency fixation of fractures. We therefore compared the trabecular localization and extent of osteoblastic alkaline phosphatase (AP) perimeters with tetracycline and osteoid perimeters in iliac crest biopsies from 7 women with postmenopausal osteoporosis and 13 women without metabolic bone disease. Fresh biopsies were chilled to -70 degrees C, and triplicate serial unfixed undecalcified cryostat sections were cut and reacted for AP, stained for osteoid, or mounted unstained. At individual remodeling sites, the mineralizing perimeter (M.Pm) was measured as the extent of a double or single label accompanied by greater than or equal to 1 lamella of osteoid and greater than or equal to 1 lamella of mineralized matrix between the mineralization front and the adjacent label. Osteoid perimeters (O.Pm) and AP perimeters (AP.Pm) were also measured. In each biopsy there was good agreement between the location of AP and bone formation (kappa statistic, range 0.71-1.0). The overall sensitivity and specificity of AP as an indicator of the location of bone formation were 0.963 and 0.902, respectively. At the level of the basic multicellular unit, in those samples in which greater than 3 active BMUs were found, there was (1) significant positive correlation between the M.Pm and both AP.Pm and AP-positive O.Pm (except 1 patient) and (2) no significant difference between the M.Pm and AP-positive O.Pm (17 of 18 patients and 18 of 18 patients at the tissue level).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
998.
Andrew Hoey Lindsay Brown Catherine Marchant Rick Atwell Conrad Sernia 《Clinical and experimental pharmacology & physiology》1992,19(11):761-766
1. Triiodothyronine (T3; 1.0 mg/kg per day subcutaneously) was administered to 10 dogs for 14 days; 10 saline-treated dogs served as controls. T3-treated dogs showed the expected physiological responses of hyperthyroidism; further, chronotropic responses to isoprenaline in vivo were significantly increased in T3-treated dogs. 2. Beta-adrenoceptor subtype density was measured in membrane preparations by displacement of 125I-iodocyanopindolol binding by the selective beta 2-adrenoceptor antagonist, ICI 118, 551. T3 treatment led to a 93% increase in right atrial beta 1-adrenoceptor density and a 141% increase in left ventricular beta 1-adrenoceptor density; beta 2-adrenoceptor densities in right atrial, left ventricular and lung membranes were unchanged. 3. T3-treatment did not change basal or maximally stimulated adenylate cyclase activities in left ventricular membranes. 4. Thus, the cardiovascular changes in experimental hyperthyroidism in dogs were accompanied by an increased chronotropic response in vivo to isoprenaline and an increased beta 1-adrenoceptor density in atrial and ventricular membranes. However, there was no corresponding change in basal or maximal responsiveness of adenylate cyclase in ventricular membranes. 相似文献
999.
1000.
Michael T Collins John R Lindsay Alka Jain Marilyn H Kelly Carolee M Cutler Lee S Weinstein Jie Liu Neal S Fedarko Karen K Winer 《Journal of bone and mineral research》2005,20(11):1944-1950
Serum FGF-23 regulation was studied in patients with hypoparathyroidism or pseudohypoparathyroidism treated with calcitriol. Serum FGF-23 levels changed in parallel in response to changes in serum 1,25-D, suggesting that FGF-23 may be regulated by 1,25-D. In addition, the phosphaturic effect of FGF-23 may be diminished in the absence of PTH action on the kidney. INTRODUCTION: Fibroblast growth factor (FGF)-23 is a recently described hormone that has been shown to be involved in the regulation of phosphate and vitamin D metabolism. The physiologic role of FGF-23 in mineral metabolism and how serum FGF-23 levels are regulated have yet to be elucidated. Three patients with mineral metabolism defects that allowed for the investigation of the regulation of FGF-23 were studied. MATERIALS AND METHODS: Patient 1 had postsurgical hypoparathyroidism and Munchausen's syndrome and consumed a pharmacologic dose of calcitriol. Patient 2 had postsurgical hypoparathyroidism and fibrous dysplasia of bone. She was treated with increasing doses of calcitriol followed by synthetic PTH(1-34). Patient 3 had pseudohypoparathyroidism type 1B and tertiary hyperparathyroidism. She underwent parathyroidectomy, which was followed by the development of hungry bone syndrome and hypocalcemia, requiring treatment with calcitriol. Serum FGF-23 and serum and urine levels of mineral metabolites were measured in all three patients. RESULTS: Patient 1 had an acute and marked increase in serum FGF-23 (70 to 670 RU/ml; normal range, 18-108 RU/ml) within 24 h in response to high-dose calcitriol administration. Patient 2 showed stepwise increases in serum FGF-23 from 117 to 824 RU/ml in response to increasing serum levels of 1alpha,25-dihydroxyvitamin D (1,25-D). Finally, before parathyroidectomy, while hypercalcemic, euphosphatemic, with low levels of 1,25-D (10 pg/ml; normal range, 22-67 pg/ml), and with very high serum PTH (863.7 pg/ml; normal range, 6.0-40.0 pg/ml), patient 3 had high serum FGF-23 levels (217 RU/ml). After surgery, while hypocalcemic, euphosphatemic, and with high serum levels of serum 1,25-D (140 pg/ml), FGF-23 levels were higher than preoperative levels (305 RU/ml). It seemed that the phosphaturic effect of FGF-23 was diminished in the absence of PTH or a PTH effect. CONCLUSIONS: Serum FGF-23 may be regulated by serum 1,25-D, and its phosphaturic effect may be less in the absence of PTH. 相似文献