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排序方式: 共有2514条查询结果,搜索用时 15 毫秒
21.
Bolton Virginia N.; Braude Peter R.; Ockenden Kim; Marsh Simon K.; Robertson Gregory; Ross Leslie D. 《Human reproduction (Oxford, England)》1989,4(6):674-679
Twenty-nine couples with an average of 5 years of infertilitywere selected for treatment by intrauterine insemination ofwashed semen (AIH). The criteria for selection were (i) thefemale partner showed no detectable fertility disorders by routinescreening; (ii) the male partner showed subnormal semen qualityon conventional semen analysis. Ovulation was stimulated uniformlywith clomiphene citrate and precipitated with human chorionicgonadotrophin (HCG). Inseminations were performed 3132h post-HCG, with the day of HCG determined by ultrasound monitoringof follicular development. The fertilizing capacity of the malepartners spermatozoa was tested in vitro using donatedhuman oocytes and/or the zona-free hamster oocyte penetrationassay. Up to eight cycles of AIH were alternated with cyclesof natural intercourse. While no pregnancies occurred in thegroup during normal coital cycles, the AIH pregnancy rate was17% per couple, but only 3% per insemination cycle. Four furtherpregnancies were achieved spontaneously in couples from thestudy group within 3 years of completion of the AIH therapyand four patients became pregnant following subsequent GIFTor IVF treatments. Neither of the in-vitro tests was helpfulin predicting the outcome of AIH, spontaneous pregnancy norof subsequent assisted conception procedures. 相似文献
22.
Adequate hemodialysis schedule 总被引:1,自引:0,他引:1
J R De Palma C F Bolton M A Baltzan R B Baltzan 《The New England journal of medicine》1971,285(6):353-354
23.
Philip S. Bolton David J. Tracey 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,88(3):473-484
Summary Experiments were performed on rats to determine the location of thalamic projecting neurones in the medulla which receive direct contacts from neck primary afferents. The medullary terminations of primary afferents from the cervical region were identified by silver staining their degenerating terminals, diffusely filling their axons with horseradish peroxidase (HRP), or reacting for transganglionically transported HRP applied to muscle or cutaneous nerves. Neurones projecting to the ventrobasal thalamus were identified in the same experimental animals by using retrograde transport of HRP or Fluoro-Gold. En passant swellings or terminals of neck primary afferents were found in the vicinity of neurones projecting to the thalamus in the dorsolateral part of the rostral cuneate nucleus, the ventral aspect of the external cuneate nucleus, and the border zone between the two. Terminals of neck afferents and retrogradely labelled cells also coincided in nucleus x. Putative synaptic contacts were found in the region between the dorsolateral part of the rostral cuneate nucleus and ventromedial external cuneate nucleus. Cutaneous afferents from the neck were associated with thalamic projecting cells located along the dorsolateral border of the rostral cuneate nucleus, and afferents from neck muscles were associated with thalamic projecting cells in the caudal third of the external cuneate nucleus and in nucleus x. 相似文献
24.
Non-Contractile Cells with Thin Processes Resembling Interstitial Cells of Cajal Found in the Wall of Guinea-Pig Mesenteric Arteries 总被引:7,自引:1,他引:7
Arterial interstitial cells of Cajal (ICC)-like cells (AIL cells) with a multipolar, irregular, elongated shape and with numerous thin (often less than 1 μm), sometimes branching, processes with lengths up to ≈60 μm were isolated enzymatically from 1st to 7th order branches of guinea-pig mesenteric artery. Some of the processes of AIL cells were growing (average speed ≈0.15 μm min−1 ) and their growth was blocked by 10 μ M latrunculin B, an inhibitor of actin polymerisation. Staining with BODIPY phalloidin, a fluorescent dye selective for F-actin, showed the presence of F-actin in the processes of AIL cells. Voltage clamp of single AIL cells revealed an inward current that was four times more dense than in myocytes and was abolished by 10 μ M nicardipine, and an outward current carried exclusively by potassium ions that was reduced by 1 m M 4-aminopyridine and/or 100 n M iberiotoxin but unaffected by 10 n M dendrotoxin-K. Imaging of intracellular ionised calcium with fluo-4 using a laser scanning confocal microscope showed local or global calcium transients lasting several seconds in ≈28 % of AIL cells. When membrane current was recorded simultaneously, the calcium transients were found to correspond to long-lasting transient outward currents, which occurred at potentials positive to −40 mV. Unlike myocytes, AIL cells did not contract in response to 1 m M caffeine or 5 μ M noradrenaline, although they responded with a [Ca2+ ]i increase. The segments of intact arteries did not stain for c-kit, a marker of ICCs. Single AIL cells stained positive for vimentin, desmin and smooth muscle myosin. The presence of ICC-like cells is demonstrated for the first time in the media of resistance arteries. 相似文献
25.
Fahy U Hopton MI Hartog M Bolton CH Hull MG 《Human reproduction (Oxford, England)》1999,14(2):285-287
The aim of this study was to evaluate the lipoprotein profile in women with hyperprolactinaemic amenorrhoea and to establish whether effective dopamine agonist therapy might have a beneficial effect. Blood samples were collected from women with hyperprolactinaemic amenorrhoea and from controls matched for age, body mass index and smoking. Follow-up blood samples were collected from women on dopamine agonist therapy as treatment for their hyperprolactinaemia. Plasma cholesterol, high density lipoprotein cholesterol, low density lipoprotein (LDL) cholesterol, very low density lipoprotein cholesterol, triglycerides, serum oestradiol and prolactin were measured. No statistically significant differences were found in the lipoprotein profile of the patient (n = 15) and control (n = 15) groups. During treatment with the dopamine agonist, bromocriptine (n = 9), significant reduction in total cholesterol [4.87 (3.98-5.87) versus 5.60 (4.55-6.61) mmol/l, P = 0.024] and LDL cholesterol [3.22 (2.01-4.23) versus 3.72 (2.59-4.93) mmol/l, P = 0.033] was noted. We conclude that beneficial alterations in the lipoprotein profile may occur in response to effective dopamine agonist therapy, presumably as a consequence of return of ovarian function and alleviation of oestrogen deficiency. Women with hyperprolactinaemic amenorrhoea should be encouraged to take effective therapy to improve their lipoprotein profile and potentially reduce their cardiovascular risk. 相似文献
26.
J. M. Davis J. Addison R. E. Bolton K. Donaldson A. D. Jones T. Smith 《International journal of experimental pathology》1986,67(3):415-430
For many years it has been accepted that fibre dimensions are the most important factor in the development of asbestos related disease with long fibres being more dangerous than short for all types of asbestos. This information has been derived from in vitro experiments and injection or implantation experiments since the kilogramme quantities of specially prepared dusts that are necessary for long term inhalation have not been available. The present study has taken advantage of the availability of a sample of amosite produced so that almost all fibres were less than 5 micron in length. The effects of this dust were compared to dust prepared from raw amosite that contained a very high proportion of long fibres. Previous data from studies with UICC amosite, which was intermediate in length, were also available for comparison. At the end of 12 months of dust inhalation, significantly more short fibre amosite was present in the lung tissue compared to the long but while the long fibre dust caused the development of widespread pulmonary fibrosis, no fibrosis at all was found in animals treated with short fibre. One third of animals treated with long fibre dust developed pulmonary tumours or mesotheliomas but no pulmonary neoplasms were found in animals treated with short fibre dust. Following intraperitoneal injection, the long fibre amosite produced mesotheliomas in 95% of animals with a mean induction period of approximately 500 days. With short fibre dust, only a single mesothelioma developed after 837 days. In previous inhalation studies with UICC amosite, relatively little pulmonary fibrosis had developed and only two benign pulmonary tumours. This would suggest that to produce a significant carcinogenic response in rat lung tissue amosite fibres must be longer than those in the UICC preparation. Following the injection of UICC amosite, however, mesotheliomas developed in the same proportion of animals and with the same mean induction period as with long fibre dust. From this it would appear that while very short fibres exhibit little carcinogenicity to either lung or mesothelial tissues, mesotheliomas can be produced by dust preparations consisting of shorter fibres than are needed to produce tumours. 相似文献
27.
Joinson C O'Callaghan FJ Osborne JP Martyn C Harris T Bolton PF 《Psychological medicine》2003,33(2):335-344
BACKGROUND: Intellectual impairments are a recognized feature of tuberous sclerosis complex (TSC), but the frequency and degree of intellectual impairments has not been systematically studied in large epidemiological samples using standardized measures. As such, the form of the IQ distribution (uni- or bi-modal) has not been established and the relationship between IQ and other features (e.g. epilepsy history) is poorly delineated. To address these shortcomings, we assessed the intellectual abilities of a large epidemiological sample of individuals with TSC, drawn from the 'Wessex' area of SW England and compared them with the abilities of their unaffected siblings. METHOD: Standardized tests were used to estimate the abilities of 108 (56 males, 52 females, median age = 25, range = 4-75) individuals with TSC and 29 unaffected siblings (14 males, 15 females, median age = 18, range = 6-55). Seizure history was obtained from informants and medical records. RESULTS: Estimated IQ was bi-modally distributed: 55.5% had an IQ in the normal range; 14% had mild to severe impairments: and 30.5% had profound disability (IQ < 21). Forty-four per cent of the individuals with TSC had an IQ < 70. In the subset of normally intelligent individuals with TSC, IQ was normally distributed with a mean of 93.6. This mean was significantly lower than the mean IQ of unaffected siblings (IQ = 105.6). All individuals with learning disability had a history of seizures that usually commenced before 12 months of age and that often presented as infantile spasms. Multivariate analyses indicated that a history of seizures as well as a history of infantile spasms was predictive of the degree of intellectual impairment. CONCLUSIONS: Intellectual abilities were bi-modally distributed in a representative sample of individuals with TSC. The likelihood of impairment was associated with a history of seizures, particularly infantile spasms. The genetic and brain basis of these findings requires further investigation. 相似文献
28.
Detection of heat-stable antigens of Campylobacter jejuni and C. coli by direct agglutination and passive hemagglutination 下载免费PDF全文
Oza AN Thwaites RT Wareing DR Bolton FJ Frost JA 《Journal of clinical microbiology》2002,40(3):996-1000
The two serotyping schemes for the detection of heat-stable antigens of Campylobacter jejuni and Campylobacter coli use the same strains for antiserum production but differ in the detection systems used for identifying agglutination. The Penner method uses passive hemagglutination (PHA) while the Laboratory of Enteric Pathogens method uses the same antisera but in a whole-bacterial-cell direct agglutination (DA) protocol. C. jejuni produces a polysaccharide capsule, which is antigenic, and is the main component detected by the PHA method. The DA method will detect both capsule antigens and lipopolysaccharide (LPS) or lipooligosaccharide (LOS) surface antigens. Comparison of both methods by using a selection of isolates from human infection has shown a range of variation in agglutination specificity, reflecting the differences in antigens detected by the two methods. While 27.4% of the 416 C. jejuni isolates reacted with the antisera raised against the same type strains by either method, the majority showed a range of more complex relationships. None of the 37 C. coli isolates reacted with the same antiserum by both methods. Together the two schemes gave a total of 102 distinct combined serogroups for C. jejuni and 16 for C. coli. Thus, while some clonally related isolates share the same capsule and LOS or LPS antigens, other strains appear to have a common capsule antigen but differ in their LPS or LOS structures or vice versa. 相似文献
29.
The measurement of CA 125 and placental protein 14 in uterine flushings in women with recurrent miscarriage; relation to endometrial morphology 总被引:2,自引:2,他引:2
Dalton C.F.; Laird S.M.; Serle E.; Saravelos H.; Warren M.A.; Li T.C.; Bolton A.E. 《Human reproduction (Oxford, England)》1995,10(10):2680-2684
The concentrations of CA 125 and placental protein 14 (PP14)were measured in uterine flushings obtained throughout the lutealphase of the cycle from eight normal fertile women. The concentrationsof both proteins increased in a similar pattern throughout theluteal phase of the cycle, with the most dramatic increase occurring6 days after their luteinizing hormone surge (day LH +6). However,a greater variation in CA 125 concentrations was seen comparedto that seen for PP14. The concentrations were compared to thoseobtained on day LH + 7 of the cycle from a group (n equals;35) of women with recurrent miscarriage. The ranges in concentrationof PP14 and CA 125 in the flushings of fertile and recurrentmiscarriage patients were very similar. However, a greater proportionof women with recurrent miscarriage (55%) had low concentrations(<5 ng/ml) of PP14 than in the control group (12.5%) andthe concentrations of PP14 in the uterine flushings were significantlyless (P < 0.05) in women with recurrent miscarriage comparedto the normal fertile group. There was no significant differencein the concentrationof CA 125 in the uterine flushings betweenthe two groups. Histological observation of the endometrialbiopsy samples from recurrent miscarriage patients gave menstrualcycle datings that ranged from day LH +2.5 to LH +6.5 with retardedendometrium (;day LH +5) in 12 of 35 (34%) patients. Of these12 patients, 10 (83%) had low PP14 concentrations and six (50%)had low CA 125 concentrations in their uterine flushings. Inthe recurrent miscarriage patients with histologically normal(sequals; day LH +5) endometrial development, 10 out of 23 (43%)also had low PP14 concentrations and 8 out of 23 (35%) had lowCA 125 in their uterine flushings. The results suggest thatPP14 is better than CA 125 as a marker for endometrial functionin this group of women. In some cases (52%) the low concentrationsof PP14 in the uterine flushings couldbe explained by retardedendometrial development but for the others the reduction inPP14 concentration in the uterine flushing was not associatedwith retardation of endometrial development. 相似文献
30.
A. D. Hughes S. Hering T. B. Bolton 《Pflügers Archiv : European journal of physiology》1990,416(4):462-466
The effect of caffeine on inward current carried by barium ions through voltage-dependent calcium channels has been investigated in single rabbit ear artery cells using whole-cell voltage-clamp techniques. Caffeine (1 –30 mM) caused a rapid and reversible concentration-dependent blockade of barium current and a related compound, 3-isobutyl-1-methylxanthine (IBMX), was a more potent inhibitor of barium current. Caffeine-induced inhibition of barium current showed no voltage- or usedependence and caffeine did not alter the steady-state inactivation of barium current. The effect of caffeine was not blocked by extracellular or by intracellular ryanodine or inclusion of both 5 mM 1,2-bis(2-aminophenoxy)-ethane N,N,N,N,-tetraacetic acid (BAPTA) and 2 mM ethylene glycol-bis(-amino ethyl ether) N,N,N,N,-tetraacetic acid (EGTA) in the intracellular solution. Rolipram and M&B 22984, non-xanthine inhibitors of phosphodiesterase, did not diminish inward barium current. The data indicate that caffeine and IBMX block voltage-operated calcium channels and it is suggested that this is due to a direct interaction of methylxanthines with the calcium channel. 相似文献