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81.
A two year (1992 to 1993) in vivo assessment of Plasmodium falciparum sensitivity to chloroquine was conducted in two communities at Dodowa (hyperendemic) and Prampram (mesoendemic) in Southern Ghana. A slightly modified World Helath Organization standard field test (7 day test) for response of Plasmodium falciparum asexual parasites to chloroquine was used for the survey. In 1992, 16.2% (12/74) responses were classified as exhibiting chloroquine resistance at RI (14.8% ) and RII (1.4%) in the dry season and 8.2% (10/122) responses at RI in the wet season in the hyperendemic community. Only a single response (1/144; 0.7%) at RI showed resistance in the mesoendemic community. The rest of the responses in both communities were classified as sensitive to chloroquine. In the hyperendemic community, 8.4% (13/154) of responses in the dry season showed resistance at RI and 1.3% (82/150) at RI (0.7%) and RII (0.7%) in the wet season in 1993. In the mesoendemic community 1 (1.0%) response was resistant at RI in the wet season. The rest of the responses were classified as sensitive responses to chloroquine. No RIII response was encountered in any of the communities. The pattern of RI and RII responses did not show any seasonal variations in the mesoendemic community. However, they were generally higher in the dry season than in the wet season in the hyperendemic community. 相似文献
82.
Summary
The present study was designed to investigate the relationships between premenstrual symptomatology, locus of control, anxiety,
and depression in women with normal menstrual cycles. Sixty-nine female participants completed a survey, comprised of the
Menstrual Distress Questionnaire (MDQ; Moos, 1968), Levenson's (1981) locus of control scales, the Depression Anxiety Stress
Scale (DASS; Lovibond and Lovibond, 1995), and a questionnaire constructed by the researchers based on the DSM-IV criteria
for Premenstrual Dysphoric Disorder (PMDD). Both overall and specific subtypes of premenstrual symptomatology were found to
correlate with external locus of control, anxiety, and depression. In addition, locus of control was found to moderate the
relationship between premenstrual symptomatology, anxiety and depression. Finally, women who were in the premenstrual phase
when completing the questionnaire scored significantly lower on the internal scale than those in either the follicular or
early luteal phases. It was concluded that an external locus of control may be associated with a susceptibility to depression
or anxiety when certain premenstrual or postmenstrual changes are experienced.
Received August 10, 2002; accepted January 12, 2003 Published online February 19, 2003
Abbreviations · ANOVA · Analysis of variance · DASS · Depression anxiety stress scale · LOC · Locus of control · MANOVA · Multivariate
analysis of variance · MDQ · Menstrual distress questionnaire · PMDD · Premenstrual dysphoric disorder · PMS · Premenstrual
syndrome
Acknowledgement The authors would like to thank John Reece, Department of Psychology and Disability Studies, RMIT University, Melbourne,
Australia, for assistance with data analysis.
Correspondence: Dr. Andrew Francis, Department of Psychology and Disability Studies, Faculty of Applied Science, RMIT University,
P.O. Box 71, Bundoora, Victoria 3083, Australia; e-mail: andrew.francis@rmit.edu.au 相似文献
83.
Penner J Meier AS Mwachari C Ayuka F Muchina B Odhiambo J Cohen CR 《Journal of acquired immune deficiency syndromes (1999)》2003,32(2):223-228
In sub-Saharan Africa, respiratory tract infections (RTI) are the leading cause of serious morbidity and mortality in HIV-infected persons. This study sought to investigate demographic, socioeconomic, and environmental risk factors for pneumonia in a cohort of HIV-infected women. The authors performed a nested case-control study in a cohort of HIV-1-infected adults followed in Nairobi, Kenya. Thirty-nine women who developed pneumonia during the follow-up period were selected as cases, and 66 women who did not develop pneumonia were randomly chosen to serve as control subjects. A questionnaire was administered in subjects' homes that assessed demographics, home environment, and socioeconomic status. Women were followed in the cohort for a median of 36.8 months (range, 27.3-39.3). Adjusting for length of follow-up period, factors associated with lower socioeconomic status (lower monthly spending [OR = 3.2; 95% CI, 1.2-8.4 per 10,000 Kenyan shilling decrease], having no savings [OR = 4.1; 95% CI, 1.4-11.9], less sturdy home construction material such as mud or cement walls [OR = 2.6; 95% CI, 1.1-5.9] or dirt floors [OR = 2.8; 95% CI, 1.0-7.6], and lack of a window in the home [OR = 5.5; 95% CI, 0.9-32.2]) and being widowed (OR = 4.3; 95% CI, 1.2-15.1) or single (OR = 3.3; 95% CI, 1.0-11.2) were associated with an increased risk of pneumonia. In multivariate analysis, widowed (AOR = 5.9; 95% CI, 1.3-26.3), single (AOR = 7.7; 95% CI, 1.6-36.4), and divorced (AOR = 4.5; 95% CI, 1.0-20.1) women, those without savings (AOR = 3.7; 95% CI, 1.2-11.7), and those living in more crowded and contagious conditions (AOR = 1.5; 95% CI, 1.1-2.1) remained at increased risk of pneumonia. If confirmed by prospective investigation, these findings could help identify persons and subpopulations of HIV-infected women with the greatest risk of pneumonia. 相似文献
84.
Ibáñez L Potau N Enriquez G Marcos MV de Zegher F 《Human reproduction (Oxford, England)》2003,18(8):1565-1569
BACKGROUND: Fetal growth restraint has been associated with FSH hypersecretion in early infancy and in early post-menarche, and with reduced uterine and ovarian size in adolescence. It is unknown whether these reproductive anomalies persist, respectively, into late infancy and into the reproductive age range. METHODS: We report follow-up findings in two age groups of girls. A cohort of infants [n=26; n=10 born appropriate-for-gestational-age (AGA) and n=16 born small-for-gestational-age (SGA)], who had been studied at the age of approximately 4 months, was assessed again at the age of 12 months. A cohort of teenagers (n=28), who had been studied at the age of approximately 14 years, was assessed again at the age of approximately 18 years; this group was complemented by a transversal cohort of similar age (n=19) for a total of 47 young women (n=27 AGA; n=20 SGA). In infants, only serum FSH was measured; adolescents underwent endocrine-metabolic screening, ultrasound assessment of uterine-ovarian size, and evaluation of body composition by dual X-ray absorptiometry. RESULTS: Serum FSH levels were higher in SGA than AGA infant girls at 4 and 12 months, and higher in SGA than AGA adolescents at 14 and 18 years (all P<0.01). Longitudinal ultrasound assessments disclosed a late-adolescent increment of uterine size that was less obvious in SGA than AGA girls. In contrast, ovarian volume remained stable in both subgroups. Compilation of longitudinal and transversal results at 18 years of age corroborated the persistent reduction in the uterine size of SGA girls (by approximately 20%; P<0.005) and in their ovarian volume (by approximately 40%; P<0.0001); moreover, SGA girls displayed not only a persistent elevation of FSH (by approximately 50%; P<0.001), but also a rise of LH and fasting insulin, as well as an excess of abdominal fat (all P<0.01). CONCLUSIONS: The gynaecology of young women born SGA was found to be characterized by hypergonadotrophinaemia and by a reduced uterine and ovarian size. 相似文献
85.
Galit Mimouni Paul Merlob Francis B. Mimouni Alona Bin‐Nun 《American journal of medical genetics. Part A》2021,185(1):46-49
Retrognathia (recessed chin) and prognathism (prominent chin) often present as signs of an underlying condition. Accurate clinical definitions are important. Yet their definitions were according to “clinical impression”, or to seldom used X‐ray criteria. We propose a statistical and anthropometric definition of retrognathia and prognathism based upon the ratio between the goniomaxillar length (distance between the gonion at the mandible angle and the subnasale and the goniomandibular length (distance between the mandible angle and the most anterior point of the bony chin). We assumed that an increase in the ratio indicates retrognathia and a decrease reflects prognathism. We conducted a prospective, observational, anthropometric study in 204 consecutive healthy term infants. Measurements took place on the second day of life, using sliding calipers. Mean ± SD of goniomandibular length (5.1 ± 0.3 cm), goniomaxillar length (5.4 ± 0.3 cm), were calculated. All measurements correlated significantly with gestational age, and with infant birthweight. The mean ± SD goniomaxillar length/goniomandibular length ratio was 1.06 ± 0.05. We defined a normal ratio as being within 2 SD of the mean, that is, between 0.96 and and 1.16. This ratio correlated with neither gestational age nor with birthweight. We conclude that the goniomaxillar length/goniomandibular length ratio can be calculated whenever retro ‐ or prognathism is suspected. A ratio outside of the 95% confidence interval should help in making this diagnosis. An increase in this ratio beyond 2 SD above the mean (1.16) could be interpreted as retrognathia and a decrease beyond 2 SD below the mean (0.96) as prognathism. 相似文献
86.
Our inability to associate distant regulatory elements with the genes they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries, we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBSs), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes they regulate. A total of 2116 and 1942 CBSs >200 kb were assembled for HMC and HMF, respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBSs, we analyzed the prevalence and distribution of chromosomal aberrations leading to position effects (disruption of a gene's regulatory environment), observing a clear bias not only for mapping onto CBS but also for longer CBS size. Our results provide an extensive data set characterizing the regulatory domains of genes and the conserved regulatory elements within them. 相似文献
87.
The oomycete Pythium ultimum is homothallic, thus a single isolate completes the sexual stage in pure culture. It has been generally assumed that homothallic oomycetes are predominantly inbreeding. In P. ultimum, antheridia occasionally develop from hyphae not directly connected to the oogonium and appear to participate in fertilization, suggesting a possible mechanism for outcrossing. We have used molecular markers to confirm that outcrossing can occur between isolates of P. ultimum. Genetic markers based on randomly amplified polymorphic DNA (RAPD) and restriction fragment length polymorphisms (RFLP) were used to distinguish isolates in a collection of P. ultimum. Two isolates displaying a high level of polymorphism were mixed and placed on media which allows the development of the sexual stage. RAPD markers were used to screen single oospore progeny to identify potential hybrids between the two parental isolates. Subsequent self-fertilization of one putative F1 yielded a F2 population which demonstrated segregation and independent assortment of RAPD and RFLP markers. A similar strategy was used to show that an isolate which is incapable of producing oospores in pure culture can outcross when mixed with a homothallic isolate. These results suggest that other homothallic oomycetes may be capable of outcrossing, and sexual reproduction may, therefore, play an important role in the generation of variation in homothallic oomycetes. 相似文献
88.
Baruch Kiln Francis Serour Kalman Fried Yigal Efrati Itzhak Vinograd 《Clinical genetics》1993,43(2):101-103
Thyroglossal duct cysts are common congenital abnormalities or developmental field defects, usually detected in early childhood. Despite their frequent occurrence, familial patterns are rare. We report on two new families with thyroglossal duct cysts. In the first family three siblings were involved, while in the second one, father and son were affected. This trait may be autosomal recessive or possibly multifactorial, as the first family would indicate, and also autosomal dominant, as the second family would suggest. 相似文献
89.
90.
Identification of a Putative Precursor to the Major Surface Glycoprotein of Pneumocystis carinii 总被引:1,自引:0,他引:1
Susan M. Sunkin Michael J. Linke Francis X. McCormack Peter D. Walzer James R. Stringer 《Infection and immunity》1998,66(2):741-746
The major surface glycoprotein (MSG) of Pneumocystis carinii f. sp. carinii is a family of proteins encoded by a family of heterogeneous genes. Messenger RNAs encoding different MSGs each begin with the same 365-bp sequence, called the Upstream Conserved Sequence (UCS), which is in frame with the contiguous MSG sequence. The UCS contains several potential start sites for translation. To determine if translation of MSG mRNAs begins in the UCS, polyclonal antiserum was raised against the 123-amino-acid peptide encoded by the UCS. The anti-UCS serum reacted with a P. carinii protein that migrated at 170 kDa; however, it did not react with the mature MSG protein, which migrates at 116 kDa. A 170-kDa protein was immunoprecipitated with anti-UCS serum and shown to react with a monoclonal antibody against a conserved MSG epitope. To explore the functional role of the UCS in the trafficking of MSG, the nucleotide sequence encoding the UCS peptide was ligated to the 5′ end of an MSG gene and incorporated into a recombinant baculovirus. Insect cells infected with the UCS-MSG hybrid gene expressed a 160-kDa protein which was N-glycosylated. By contrast, insect cells infected with a baculovirus carrying an MSG gene lacking the UCS expressed a nonglycosylated 130-kDa protein. These data suggest that in P. carinii, translation begins in the UCS to produce a pre-MSG protein, which is subsequently directed to the endoplasmic reticulum and processed to the mature form by proteolytic cleavage. 相似文献