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21.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
The relationship between fecundability and month of birth was investigated
in a cohort of 1526 women who married between 1802 and 1929, using only
women whose first marriage occurred before the age of 35 years. On the
basis of their time to pregnancy (TTP, calculated as time between wedding
and first birth minus gestational length), women were categorized into two
groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348)
and subfecunds (TTP >18 months, n = 118). By use of logistic regression,
cosinor functions with a period of 1 year or 6 months and variable shift
and amplitude were fitted through the monthly odds of subfecunds versus
fecunds. The best fitting curve was unimodal, with a zenith in September (P
= 0.13 for H0: no differences). Exclusion of childless women (n = 36,
minimum follow-up 5 years) from the subfecunds led to a similar curve (P
< 0.01), while childless women, as compared with fecunds, showed a birth
distribution that was best represented with a bimodal curve with zeniths in
January and July (P = 0.06). This study provides evidence for the existence
of differences in fecundability by month of birth. The cause of this
relationship is unclear, but may lie in a melatonin-dependent circannual
variability of the quality of the oocyte.
相似文献
22.
The localisation of the principal blood group antigens has been studied in human liver. These blood group antigens included the erythrocyte antigens and the antigen of the major histocompatibility complex. This study was performed by the indirect immunofluorescence technique using polyclonal antibodies of human or animal origin and monoclonal antibodies from hybridomas. This study has shown that the normal hepatocyte is lacking in blood group antigens. On the contrary, the biliary cell was rich in antigenic markers: the main antigens expressed were Lewis, Pr, HLA-A and B antigens. In Kupffer cells, only i and HLA-DR antigens were clearly expressed. The endothelial cells of blood vessels mainly show A, B, H, HLA-A and B antigens; HLA-DR and Pr are slightly expressed. HLA-DR antigens were more strongly expressed on veins than on arteries. Dendritic cells have been identified in the portal space of human liver. They bore i and HLA-DR antigens. 相似文献
23.
Estimation of the genetic contribution of presenilin-1 and -2 mutations in a population-based study of presenile Alzheimer disease 总被引:11,自引:4,他引:11
Cruts M; van Duijn CM; Backhovens H; Van den Broeck M; Wehnert A; Serneels S; Sherrington R; Hutton M; Hardy J; St George-Hyslop PH; Hofman A; Van Broeckhoven C 《Human molecular genetics》1998,7(1):43-51
Two closely related genes, the presenilins ( PS ), located at chromosomes
14q24.3 and 1q42.1, have been identified for autosomal dominant Alzheimer
disease (AD) with onset age below 65 years (presenile AD). We performed a
systematic mutation analysis of all coding and 5'-non-coding exons of PS -1
and PS -2 in a population-based epidemiological series of 101 unrelated
familial and sporadic presenile AD cases. The familial cases included 10
patients of autosomal dominant AD families sampled for linkage analysis
studies. In all patients mutations in the amyloid precursor protein gene (
APP ) had previously been excluded. Four different PS -1 missense mutations
were identified in six familial cases, two of which where autosomal
dominant cases. Three mutations resulted in onset ages above 55 years, with
one segregating in an autosomal dominant family with mean onset age 64
years (range 50-78 years). One PS -2 mutation was identified in a sporadic
case with onset age 62 years. Our mutation data provided estimates for PS
-1 and PS -2 mutation frequencies in presenile AD of 6 and 1% respectively.
When family history was accounted for mutation frequencies for PS -1 were
9% in familial cases and 18% in autosomal dominant cases. Further,
polymorphisms were detected in the promoter and the 5'-non-coding region of
PS -1 and in intronic and exonic sequences of PS -2 that will be useful in
genetic association studies.
相似文献
24.
All citizens (N = 22066) aged 16 to 65 of a medium-sized Belgiantown were personally invited to CPR training sessions held intheir neighbourhood. 1152 responded by attending a trainingsession. Those who did not so respond were surveyed (randomsample N=600) for reasons of their not coming. The sample fittedwell with census data for gender, age and suburb location butnot for job, because retired persons and women at home wereover represented. 123 persons did not want to answer the questions. 116 personssaid they were already trained in CPR, 276 said they would accepton a future occasion and 82 said they would not. Three personsdid not answer this question. There was no discrimination for job, gender and suburb locationbetween those who did and did not accept a future training opportunity,nor was the existence of a heart patient among relatives. Theolder the person, the less inclined was that person to participatein CPR training (age effect x2 = 17.17, d.f. = 9, P<0.05).The 276 who accepted future training, chose their workplace(221) and/or their social meeting place (club etc.) as the placewhere this future training should be held. We suggest that CPR training is well accepted and that the trainingopportunities should be given at places of work and social gatherings. 相似文献
25.
JORENS PH. G.; VAN DEN HEUVEL P. A.; CUYKENS J.-J.; VAN CAUWELAERT P. A.; PARIZEL G. A.; MERTENS A. N. 《European heart journal》1990,11(5):476-478
This article describes a case of infective aortic valve endocarditisdue to Fusarium oxysporum occurring 4 years after coronary arterybypass grafting. It is the first reported case of endocarditiscaused by Fusarium. 相似文献
26.
ERIKSSON L. I.; LENNMARKEN C.; STAUN P.; VIBY-MOGENSEN +M.D. PH.D. J. 《British journal of anaesthesia》1990,65(4):487-493
In order to evaluate the use of the post-tetanic count (PTC)method during repetitive administration of vecuronium, we studied20 patients allocated randomly to one of two groups: 10 patientsreceived droperidol-fentanyl anaesthesia (control group); 10other patients were given droperidol-fentanyl anaesthesia modifiedsubsequently by addition of 0.5% isoflurane (isoflurane group).Before tracheal intubation, a bolus dose of vecuronium 0.08mg kg1 was given i. v. followed by repeated doses of0.03 mg kg1. The twitch response of adductor polliciswas recorded after supramaximal stimulation of the ulnar nerveat the wrist using a Myograph 2000 neuromuscular transmissionanalyser. In the control group, a close correlation was foundbetween PTC and time to first reaction to train-of-four (TOF)nerve stimulation. This relationship was unchanged when comparingthe bolus dose and each of eight consecutive maintenance doses.Further, the degree and the duration of intense block were unchangedafter each of the eight maintenance doses. In the isofluranegroup, the relationship between PTC and time to first reactionto TOF stimulation remained unchanged after addition of isoflurane.However, isoflurane caused a significant prolongation of theduration of intense block and a corresponding lower PTC in allpatients. We conclude that PTC is a reliable method to evaluateintense neuromuscular block caused by vecuronium, even afterrepetitive administration of the drug and in combination with0.5% isoflurane.
Presented in part at the annual meeting of the American Societyof Anesthesiologists, San Francisco, October 1988. 相似文献
27.
Background: The complications of the gastric pouch in gastric bypass surgery are well known. Since the first report of this
surgery 30 years ago, new technical aspects that make it safer and more effective have been implemented. Methods: As a modification
of gastric bypass, the authors have performed 305 vertical banded gastroplasty-gastric bypass procedures. Two groups of patients
underwent the procedure: Group I (n = 206) without a limb of jejunum interposed between the gastric pouch and the excluded
stomach, and Group II (n = 99) with a limb of jejunum interposed between the pouch and the stomach. The results regarding
excess weight loss and complications of the gastric pouch during the first year after surgery were compared. Results: Age,
sex, initial weight, body mass index, and percentage of ideal weight were similar in both groups. Excess weight loss was also
similar. The complications in Group I were 1 leak, 3 left subphrenic abscesses, 2 erosive gastritis with bleeding, 1 stenosis
of the gastrojejunostomy, 1 perforated ulcer, and 4 marginal ulcers with bleeding. Two patients in Group II developed bleeding
from the staple-line. Conclusions: These preliminary data suggest that complications of the gastric pouch can be reduced by
interposing a limb of jejunum between the pouch and the excluded stomach. This is an early experience; long-term results are
pending. 相似文献
28.
Grannum R. Sant M.D. Angelo A. Ucci Jr. M.D. PH.D. Edwin M. Meares Jr. M.D. 《Urology》1983,21(6):632-634
A renal tumor developing in a patient receiving cyclophosphamide (Cytoxan) therapy for Wegener granulomatosis is reported. The tumor was similar histologically to the "immunoblastic" sarcoma that develops in renal allograft recipients as a complication of immunosuppressive therapy. This case report strengthens the cause and effect relationship between immunosuppressive drug usage and the subsequent development of neoplasia. 相似文献
29.
JC VANCE DC CHANT DI TUDEHOPE PH GRAY AJ HAYES 《Journal of paediatrics and child health》1997,33(6):504-508
Objectives: To describe the physical growth patterns of infants born to narcotic dependent mothers (INDM) over a 12 months period and, if possible, to relate the growth to drug taking patterns during pregnancy.
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM. 相似文献
Methodology: The growth of a cohort of 43 INDM was measured during the first 12 months of life. Weight and length measurements were compared with percentile charts and converted to Z scores. Questionnaire data about drug taking practices, demographic variables and the neonatal period (including withdrawal scores) were obtained.
Results: Twenty-four (55.8%) of INDM had evidence of neonatal drug withdrawal requiring treatment with phenobarbitone. At birth, Z scores for weight and length indicated relative intrauterine growth retardation. By 12 months, there had been some catch up growth, but Z scores for weight and length were still below zero. Persistent weight retardation at 12 months was correlated with methadone dosage during pregnancy, but not the need for phenobarbitone therapy.
Conclusions: The growth patterns of INDM in the first 12 months of life indicated that at birth there was evidence of intrauterine growth retardation, but by 12 months the growth was little different from the rest of the community. There appears to be some influence of narcotic agents taken while pregnant on subsequent growth of INDM. 相似文献
30.