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Detecting pre-ovulatory luteinizing hormone surges in urine   总被引:2,自引:1,他引:2  
The study objectives were to determine (i) if pre-ovulatory luteinizing hormone (LH) surges, undetected in urine by two immunoradiometric assays (IRMA), were detectable by an ultrasensitive immunofluorometric assay (IFMA) and (ii) the influence of creatinine adjustment on the detection and timing of the urinary LH surges. Daily urine specimens were contributed by healthy 25-36 year old volunteers during 14 ovulatory menstrual cycles for an epidemiological study conducted in 1983-1985. Specimens were selected as having been previously assayed by two IRMA without consistently detecting LH surges. These urine specimens were remeasured using an IFMA and adjusted for creatinine concentration. IFMA measurements revealed unambiguous LH surges in all cycles. Adjusting IRMA urinary LH values for creatinine concentrations revealed previously undetected LH surges in four of eight cycles. Creatinine adjustment also altered the timing of IRMA and IFMA LH surges by 1-5 days. These results demonstrate an IFMA that detects pre- ovulatory LH surges in unpreserved, frozen urine from cycles where such surges were previously undetectable. Further, creatinine adjustment can markedly affect detection and timing of the onset and peak of the urinary LH surge. While our analysis suggests that this adjustment improves the validity of the LH measure, this requires further investigation.   相似文献   
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BACKGROUND. Recent years have seen a vast increase in the amount of health promotion activity undertaken in general practice. AIM. This study set out to identify the level of general practitioner and nurse involvement in activities aimed at coronary heart disease prevention and to examine variations in involvement. METHOD. A questionnaire survey was undertaken of a sample of general practitioners across England and the nurses who worked in their practices. RESULTS. Of 1696 randomly selected general practitioners 64% completed a questionnaire, of 928 practice nurses 71% responded and of 682 health visitors and 679 district nurses 52% and 40% responded, respectively. Of the general practitioners 94% reported that they were involved in assessing lifestyle risk factors in the routine consultation and regular assessments most commonly involved blood pressure testing and inquiry about smoking status. Eighty six per cent of practices were reported by the practice nurse as having well person clinics; these clinics were usually run by the practice nurse. Clinics for the management of specific lifestyle risk factors were also usually run by practice nurses, although many doctors were involved in hypertension clinics and cholesterol clinics. Health visitors and district nurses had a low level of involvement in this practice based clinic activity. Involvement of general practitioners and practice nurses in coronary heart disease prevention was associated with training in health promotion and positive attitudes towards prevention and health promotion. The level of involvement of practice nurses in health promotion was associated with the support received from primary health care facilitators, family health services authorities and district health authorities. CONCLUSION. Members of the primary health care team appeared to have their own distinct area of preventive activity. However, this division did not appear to be a result of organized teamwork and deployment of skills and expertise according to a clearly defined management protocol. Instead it seemed to be a product of general practitioner contract and management arrangements which tended to encourage an approach to general practice health promotion which revolved around the practice nurse and which hindered the development of a broader team based approach to planning and delivery of health promotion in relation to the needs of the practice population.  相似文献   
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The detection of clinical isolates with decreased fluoroquinolone susceptibilities and a resistance mechanism is of epidemiological and clinical interest. We studied the susceptibilities of 62 clinical isolates and 2 American Type Culture Collection reference strains of Haemophilus influenzae to ciprofloxacin, levofloxacin, moxifloxacin, and nalidixic acid by the microdilution and disk diffusion methods. The ciprofloxacin MICs for 34 of the isolates were >/=0.12 micro g/ml (range, 0.12 to 32 micro g/ml), and the ciprofloxacin MICs for 28 matched control isolates were /=0.5 micro g/ml and the vast majority of those for which nalidixic acid MICs were >/=32 micro g/ml exhibited amino acid changes in GyrA and ParC. Nalidixic acid and the other three fluoroquinolones studied could be used to screen H. influenzae isolates for the detection of decreased susceptibilities to quinolones due to the acquisition of two amino acid changes in the QRDRs of GyrA and ParC (sensitivity, >95%; specificity, >80%).  相似文献   
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Human cleaving pre-embryos at 2 and 3 days and cavitated pre-embryos at 5 days post-insemination have been examined for cell number and the incidence of mononucleated cells. At least 60% of polynucleate or anucleate cells have been detected at all these stages and regardless of morphological grading at day 2. It is concluded that even by the time at which pre-embryo replacement would occur therapeutically, the majority of pre-embryos are unlikely to have full developmental potential. The possible origins of the abnormalities of nucleocytoplasmic ratios are discussed.  相似文献   
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"Early" breast cancer is a systemic disease in the majority of cases. Progress has been and is being made toward the determination of those women at risk of recurrence. Attractive as it seems, the value of systemic adjuvant therapy, given at the time of minimal tumour load i.e., after mastectomy, is not proven. Therefore, for the average case it is better to treat the cancer locally and to observe and leave further evaluation of systemic therapy to those centres which are able to conduct controlled, randomized trails.  相似文献   
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