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Of 70 cycles stimulated with clomiphene and human menopausal gonadotropin (hMG) for an in vitro fertilization-embryo transfer (IVF-ET) program, a short luteal phase of 11 days or less was found in 18. In this group the mean estradiol and progesterone levels were elevated in the early luteal phase. Despite the elevated initial values, progesterone levels fell rapidly at the mid luteal phase as a sign of premature luteolysis. The mean total amount of gonadotropin administered and the mean number of follicles punctured and of oocytes recovered did not show any significant difference between the groups of normal and short luteal phases. The present findings support the theory that hyperestrogenism in the early luteal phase may initiate the premature luteolysis observed in clomiphene-menopausal gonadotropin-stimulated cycles.  相似文献   
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Gangliosides of cultured astroglia   总被引:3,自引:0,他引:3  
Cultured astrocytes prepared from newborn rat brain and 13-day-old chick embryonic brain were analyzed qualitatively and quantitatively for ganglioside content. All preparations contained approximately the same total level: 2.4-3.4 micrograms N-acetylneuraminic acid (NeuAc)/mg protein. In contrast, the value for primary cultures of neurons from chick embryonic brain was 5.9. The non-hexosamine-containing species, GM3 and GD3, comprised 75-85% of the total in astroglial cultures, the remainder consisting mainly of structural types other than the gangliotetraose series; choleragenoid assay revealed the latter to be virtually absent or to comprise at most a few percent. Deficiency of gangliotetraose synthesizing ability was indicated by the very low level of UDP-GalNac:GM3 N-acetylgalactosaminyltransferase detected in the cells. Treatment of cultured astrocytes with astroglial growth factor 2 or dibutyryl cyclic AMP caused little if any change in quantity or pattern of gangliosides. The large majority of cells stained in a manner characteristic of astrocytes: positive for glial fibrillary acidic protein, negative for galactosyl ceramides. Staining with cholera toxin and anti-GM1 antibody was essentially negative, as was that with tetanus toxin, A2B5 monoclonal antibody, and antibody to GD3. All evidence thus points to cultured astrocytes of rat and chick brain containing appreciable gangliosides, most of which are GM3 and GD3 with the majority of the remainder comprising structures other than the gangliotetraose type.  相似文献   
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BACKGROUND: In patients with intermittent claudication, exercise in the form of walking is effective in reducing pain and maximising achievable walking distance. However, data are lacking on the implementation of walking exercise in these patients. AIMS: To explore the current behaviour and views of patients with intermittent claudication towards taking walking exercise. DESIGN OF STUDY: Postal questionnaire and focus group meetings. SETTING: Two academic general practice networks (Utrecht and Maastricht Universities) in The Netherlands. METHOD: Three hundred and seventy-five patients with intermittent claudication, selected from the files of general practitioners participating in two academic general practice networks, were sent a postal questionnaire; 216 (58%) were returned. Nine of these responders also attended a focus group meeting. RESULTS: Seventy per cent (151/216) of the patients reported having received advice about walking exercise. If specified, the advice given most often recommended walking in the local neighbourhood (56%, 84/151). Fifty-two per cent (113/216) of all patients actually performed walking exercise and only 32%of them received any kind of supervision. Among the barriers for taking walking exercise, 'comorbidity', 'lack of (specific) advice' and 'lack of supervision' were often mentioned. Among the stimuli to start and continue walking, 'following the doctor's advice', 'relief of complaints' and 'a better general condition' were often mentioned by patients. CONCLUSIONS: Walking exercise was not carried out by almost half of patients with intermittent claudication in this study. Lack of specific advice and supervision were found to be important barriers to taking walking exercise.  相似文献   
15.
In this paper we describe the design and synthesis of 18 derivatives of the antimicrobial atovaquone which were substituted at the 3-hydroxy group by ester and ether functions. The compounds were evaluated in vitro for their activity against the growth of Plasmodium falciparum, the malaria causing parasite. All the compounds showed potent activity, with IC50 values in the range of 1.25–50 nM, comparable to those of atovaquone and much higher than chloroquine or quinine.  相似文献   
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In previous reports, we described the experimental development of a hypocholinergic state in rats following the total replacement of dietary choline by an artificial isostere, N-aminodeanol (NADe). NADe shares most of the physicochemical and biochemical characteristics of choline (Ch) but is utilized less efficiently in pathways leading to the formation of both acetylcholine and phospholipids. This experimental model mimics many of the features of human degenrative dementias. We now discuss the behavioral and physiological effects of restoring a normal diet after the hypocholinergic state has become well established. The procedure by which that state was induced has been described in detail in earlier publications. After replacing Ch in the diets of weanling rats for 270 days, NADe replaced 70-85% of the phospholipid-bound Ch in plasma, brain, and peripheral tissue. When dietary NADe was removed and Ch was restored in the diet, NADe disappeared and plasma and erythrocyte (RBC) choline levels returned to normal within 30-60 days. Quinuclidinyl benzilate (QNB) binding showed that muscarinic receptors continued to be depressed in animals remaining on the NADe diet, but returned to control levels in the reversal group. There were no differences in cholinesterase activity among the three treatments. Choline acetyltransferase activity returned to control levels, while continuing to be lower in the NADe animals. Liver lipids were elevated in the latter and not significantly different in the control and reversal groups. Among physiological functions, body weight increased more rapidly in the reversal group than in animals continuing on the NADe diet. Brain weights of the reversal animals were significantly greater than those of animals not reversed, but less than controls. Core body temperatures did not differ from controls at any time during the reversal period. Behaviorally, nociceptive thresholds indicative of sensory-reflexive and sensory-perceptual responses remained significantly below normal, that is, a hyperalgesic state. Reversal animals also remained hyperactive and displayed memory significantly poorer than those on the normal diet, that is, no improvement over animals continuing on NADe. In general, the results suggest that behavioral losses induced by NADe reflect persisting changes in the CNS, despite essentially complete recovery of biochemical parameters. The changes may be morphological or be associated with adaptive changes in other neurochemical events in the CNS.  相似文献   
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Summary The costs of the public health and social security system supporting adults 40–50 years old with Down's syndrome during one year (1984) have been investigated in the county of Aarhus, representing about 10% of the Danish population. 77% of the probands live in institutions, the rest in private homes or sheltered residences. The average yearly price of an institutionalized adult is DKr. 237,900 =US$ 21,128 = £ 18,174. If the person lives in a private home, the same figures are DKr. 107,239 =US$ 9,524= 8,393. Average for all probands: DKr. 207,587 = US$18,436 = £ 15,858, which is 127% of a skilled worker's salary.  相似文献   
20.
The cholesterol synthesis of rhesus monkey erythrocytes parasitized by Plasmodium knowlesi and human erythrocytes infected by P. falciparum, as measured by incorporation of [1-14C]acetate and 3H2O, was almost undetectable, concordant with very low levels of measurable 3-hydroxy-3-methyl glutaryl-CoA reductase activity. In addition, both types of infected cells exchanged cholesterol with the plasma at the same rate as uninfected cells. The data do not exclude the possibility of cholesterol transfer from uninfected to infected cells.  相似文献   
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