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1.
A retrospective follow-up study to ascertain the relationship between the level of serum zinc and its rate of change during gestation and birthweight was conducted in 476 women of lower socioeconomic status. Serum zinc concentrations measured at approximately 16 (early) and 32 weeks (later) in gestation were both found to be significant predictors of birthweight. Even after controlling for gestational age at birth and other determinants of birthweight, for each microgram/dl increase in serum zinc early and later in pregnancy, birthweight increased by 5.8 and 8.6 g, respectively. Furthermore, after adjustment for initial zinc levels both the total change (beta = -7.0, P = 0.0007) and the rate of change (beta = -60.8, P = 0.007) in serum zinc during pregnancy were inversely associated with birthweight, i.e., the larger the fall in serum zinc during pregnancy, the smaller the infant. Low serum zinc level (less than 60 micrograms/dl) late in pregnancy was associated with greater than a five-fold increase in the odds (OR = 5.8, 95% CI = 1.8, 16.4) of giving birth to a low birthweight infant. The results of this study suggest a threshold for maternal serum zinc below which the prevalence of low birthweight increases rapidly.  相似文献   
2.
OBJECTIVES: The introduction of 48-hour wireless pH testing offers clinicians a new alternative for the objective documentation of reflux. The success of transnasal wireless pH capsule placement has not been previously described. The purpose of this investigation was to describe our experience with transnasal wireless pH capsule placement. METHODOLOGY: All patients undergoing unsedated transnasal esophagoscopy and wireless pH capsule placement between January 1, 2003 and July 31, 2003 were prospectively evaluated. Data concerning patient tolerance, success of capsule placement and function, complications, and pH recordings were collected. RESULTS: During this time, 46 persons were evaluated. The mean age of the cohort was 52 years. Of the patients, 50% were male. The indications for the procedure were chronic cough (18/46), gastroesophageal reflux disease (18/46), and larygopharyngeal reflux (10). Of the procedures performed, 85% (39/46) were successful. Complications included epistaxis (2/46), laryngospasm (2/46), and vasovagal reaction (1/46). CONCLUSIONS: The transnasal placement of a wireless pH capsule is a safe and effective diagnostic adjunct to unsedated transnasal esophagoscopy.  相似文献   
3.
C4 is composed of two tightly linked genes (C4A and C4B) lying within the major histocompatibility complex of chromosome 6 that can be demonstrated by agarose gel electrophoresis. Seven alleles and five alleles at the C4A and C4B loci, respectively, were detected in 169 black individuals from the southeastern United States. Furthermore, the phenotypic frequencies of C4A6, C4A5, C4A4, C4B4, C4B3, and C4BQO were significantly different between black and white Americans.  相似文献   
4.
D Schwartz  B F Banner  D L Roseman  J S Coon 《Cancer》1986,58(9):2082-2088
Multiple, synchronous, apparently primary carcinomas of the colon are a relatively common occurrence. The DNA ploidy in 23 colon carcinomas from 10 patients was determined to see if this parameter supported common or independent origins for such synchronous lesions. Paraffin blocks of each tumor were prepared for flow cytometry, then analyzed for nuclear DNA content. In 3 of the 10 cases, the tumors within each colon differed with respect to DNA ploidy; in four cases all tumors were diploid; and in three cases both (all) tumors within each colon had identical aneuploid DNA indices. Tumors from the same colon with identical DNA histograms often had dissimilar histology. The replicate aneuploid DNA indices strongly suggest a common origin for the multiple tumors within these colons; tumors in the other groups are compatible with either single or multiple origins. These findings suggest that multiple "primary" colon carcinomas may, in some cases, arise as translumenal metastases from an initial single lesion.  相似文献   
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We have developed a database of lymphoid polypeptides detected by two-dimensional polyacrylamide gel electrophoresis to aid in studies of leukemogenesis and of mutation affecting protein structure. In prior studies, we observed a 19-kDa phosphopolypeptide which was induced with proliferation in mature T cells and constitutively expressed in immature thymocytes. In this report we describe the identification of this polypeptide as the phosphorylated form of dUTPase (EC 3.6.1.23), following cDNA cloning of the gene, based on a partial amino acid sequence of the phosphopolypeptide. Studies of the expression and phosphorylation of dUTPase in human T cells indicate that accumulation and phosphorylation of dUTPase in mature T cells occur in a cell cycle-dependent manner. Interestingly, noncycling immature thymocytes express constitutively high levels of phosphorylated and unphosphorylated dUTPase. These results suggest an important role for dUTPase in immature thymocytes that is independent of proliferation.  相似文献   
10.
OBJECTIVE: To examine the predictors of damage in a multiethnic cohort of systemic lupus erythematosus (SLE) patients with a specific focus on damage at baseline. Patients and METHODS: SLE patients from a multiethnic US (Hispanic, African-American and Caucasian) cohort (LUMINA: Lupus in Minority populations, Nature versus nurture) were included if they had > or =6 months of follow-up in the cohort. Damage was measured with the Systemic Lupus International Collaborating Clinics (SLICC) Damage Index (SDI). The dependent variable was the change in SDI score between study visits. Predictors were from the preceding visit. Variables known to affect damage accrual in SLE were included in the analyses. RESULTS: Three hundred and fifty-two patients (82 Hispanics, 153 African-Americans and 117 Caucasians) representing 1795 patient visits were included. Previous damage was found to be a significant predictor of subsequent damage accrual (P < 0.0001). Other variables predictive of subsequent damage accrual were disease activity (P < 0.0001), older age (P = 0.041) and use of corticosteroids (P = 0.0048). CONCLUSIONS: Once damage occurs in SLE, further damage is expected to occur. This is more likely to be the case if disease activity persists. These data have clinical implications for the management of SLE patients.  相似文献   
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