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991.
Affected-sib-pair analyses were performed using 104 Caucasian families to map genes that predispose to insulin-dependent diabetes mellitus (IDDM). We have obtained linkage evidence for D6S446 (maximum lod score [MLS] = 2.8) and for D6S264 (MLS = 2.0) on 6q25-q27. Together with a previously reported data set, linkage can be firmly established (MLS = 3.4 for D6S264), and the disease locus has been designated IDDM8. With analysis of independent families, we confirmed linkage evidence for the previously identified IDDM3 (15q) and DDM7 (2q). We also typed additional markers in the regions containing IDDM3, IDDM4, IDDM5, and IDDM8. Preliminary linkage evidence for a novel region on chromosome 4q (D4S1566) has been found in 47 Florida families (P < .03). We also found evidence of linkage for two regions previously identified as potential linkages in the Florida subset: D3S1303 on 3q (P < .04) and D7S486 on 7q (P < .03). We could not confirm linkage with eight other regions (D1S191, D1S412, D4S1604, D8S264, D8S556, D10S193, D13S158, and D18S64) previously identified as potential linkages.  相似文献   
992.
OBJECTIVE: To analyze the changes in soluble interleukin 2 receptor (sIL-2R) levels following treatment of patients with rheumatoid arthritis (RA). METHODS: Serial measurements of sIL-2R levels were made over 24 weeks in 40 patients with RA, treated with intramuscular (im) gold plus 3 im injections of either 120 mg methylprednisolone acetate or placebo. RESULTS: sIL-2R levels were reduced in the glucocorticoid treated group in contrast to the gold only group, where levels initially increased. At 24 weeks, mean sIL-2R levels did not significantly differ from pretreatment levels in either group, despite improvements in clinical measures. CONCLUSIONS: In our study, sIL-2R levels do not correlate with short term clinical measures of disease activity. Their significance for longer term prognostic use remains to be determined.  相似文献   
993.
994.
Data of epidemiologic interest often occur as spatial information during each of several time periods. In most cases data are available from a set of regions or localities which can be viewed as points in a plane. Although contour mapping is useful for displaying these data, the lack of data for all data points in a region may lead to erroneous interpretation. In this paper we use stimulation to investigate the impact of missing data points for contour mapping using two distinct simulated spatial-time distributions for epidemiologic variables. A model for the occurrence of malaria in localities randomly distributed in one region is chosen as the prototype for data generation.  相似文献   
995.
American Indians and Alaska Natives die younger and at higher rates proportionately than members of the general United States population. Causes of death among Native peoples in the U.S. have been the subject of numerous studies by health care professionals and social scientists. Many of these deaths are considered excess deaths, that is, deaths that occur statistically beyond the rate of incidence of the larger population. This paper examines 46 studies of excess deaths published within five years (1987 to 1993) and based on data gathered within ten years (1982 to 1992) and critiques the studies for methodology and context. Existing studies of excess death among Native peoples are limited by a lack of definitional clarity, ethnic misclassifications, lack of multidisciplinary and Native representation on research terms, superficial analysis of statistical findings, overrepresentation of data for some tribes and underrepresentation for others, bias for quantitative research methods and unbalanced prioritization.  相似文献   
996.
The amount of procollagen I carboxyterminal propeptide (PICP) in crevicular fluid (CF) was measured in three periodontitis patients. Samples were collected from 29 sites before treatment (scaling, root planing, and curettage) and 2, 5, 10, 20, and 40 days after treatment, by placing two paper strips in periodontal pockets for 5 s. The amount of fluid in strips was measured by the Periotron device. Control samples were collected from subjects with minimal gingival inflammation. PICP was extracted into saline solution and determined by a radioimmunologic method. Plaque index, papilla bleeding index, and pocket depth were recorded before and 40 days after treatment. The CF PICP mean concentration was 4.2 mg/l in the pretreatment samples. Five days after treatment a statistically significant increase in PICP concentration was seen in all subjects. The peak appeared on days 5 or 10 in 27 sites. The mean peak PICP concentrations of the subjects were 5-10 times higher than the pretreatment values. Twenty days after treatment, mean PICP concentration decreased to pretreatment level. PICP concentrations did not correlate with the clinical parameters. In control samples PICP amounts were below the detection limit. CF PICP is a new marker of type I collagen metabolism in periodontal tissues. It was concluded that elevated PICP concentrations in CF after periodontal treatment reflected increased type I collagen synthesis in periodontal tissues and that the peak in type I collagen synthesis takes place 5-10 days after treatment.  相似文献   
997.
The relationships of longitudinal biological measures to longer-term outcome in depressed patients have not been well explored. This study was designed to investigate whether in a sample of depressed patients: (a) symptomatic and functional outcome at 1 year was significantly different in psychotic major depressed (PMD) patients as compared with nonpsychotic major depressed (NPMD) patients and (b) high urinary or plasma cortisol levels at baseline or 1 year were associated with poorer outcomes at 1 year. Forty-two depressed patients (9 psychotic, 33 nonpsychotic) were evaluated at baseline and at 1 year using a battery of clinical ratings and measures of cortisol. A group of normal, healthy control subjects were similarly evaluated at baseline. At 1-year follow-up, PMD patients did not differ from NPMD patients in their Hamilton Depression Rating Scale (HDRS) and Brief Psychiatric Rating Scale scores (BPRS), but PMD patients demonstrated significantly poorer social and occupational functioning. Significant correlations were observed (n = 18) between higher levels of urinary and plasma cortisol at 1 year and poorer social and occupational functioning at 1 year, independent of the degree of residual depression. In contrast, baseline measures of urinary and plasma cortisol did not predict social and occupational functioning at 1 year.  相似文献   
998.
BACKGROUND: An increased risk of laparoscopic port wound tumor implantation in the presence of overt or covert abdominal malignancy has been identified. PURPOSE: A porcine laparoscopic colectomy model has been used to quantify the influence surgical practices may have on tumor cell implantation. METHODS: 51Cr-labeled, fixed HeLa cells were injected intraperitoneally before surgery. Tumor cell contamination of instruments, ports, security threads, and excised wound margins was assessed by gamma counting. RESULTS: Greatest contamination occurred in ports used by the operating surgeon under pneumoperitoneum (64 percent of all port wound tumor cells) and mechanical elevation (76 percent). Gasless surgery in patients in the head-down position increased the rostral accumulation of tumor cells in the abdomen and right upper quadrant port wound by 330 and 176 percent, respectively. Under pneumoperitoneum, port movement was the major contributor to port leakage and wound contamination (21 percent of total recovered wound tumor cells per port). Tumor cells were not carried in aerosol form. Instrument passage and the withdrawal of security threads through the abdominal wall increased port wound contamination 430 and 263 percent, respectively, over pneumoperitoneum control ports. Preoperative lavage reduced by 61 percent, but did not eliminate, wound contamination. CONCLUSION: This porcine model may be used to evaluate surgical factors for the impact on port wound contamination.  相似文献   
999.
The origins of the -28 A->C and frameshift Cd 11 - T(Fs CD 11-T)alleles were investigated by beta-globin cluster haplotype analysis. These alleles were found in a Mexican mestizo family with beta-thalassemia (beta-thal). The -28 A->C mutation was described previously in Kurdish Jews linked to the most common haplotype in the world(+----++),the same haplotype observed in this Mexican family. Therefore, it is not possible to assess a new origin of the -28 A->C mutation in our population. The Fs Cd 11 -T allele, not reported to date in any other populations, was linked to the -++--+-haplotype (sixth in frequency in the world). This haplotype has not been reported in association with any beta-thal mutant, suggesting a Mexican origin for the Cd 11 -T mutation.  相似文献   
1000.
Primary amyloidoma of the chest wall presents as an aggressive tumor that causes local destruction. It is best treated with wide local excision and reconstruction as required, which usually is curative. A search for occult systemic disease also is recommended.  相似文献   
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