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541.
542.
To investigate whether the association between agricultural pesticide use and the risk of non-Hodgkin's lymphoma (NHL) is modified by a family history of hematopoietic cancer, including leukemia, myeloma, and lymphoma, we analyzed pooled data on white men from three population-based, case-control studies of NHL conducted in Iowa/Minnesota, Kansas, and Nebraska. Information on the agricultural use of insecticides, fungicides, and herbicides; a family history of cancer; and other risk factors was obtained by interviewing 973 cases and 2,853 controls or, if deceased, their next-of-kin (37% of cases, 43% of controls). The NHL risk was estimated by odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for age, state of residence, type of respondent, and use of hair dye. Compared to men with no family history of cancer, the ORs (95% CIs) of NHL was 1.5 (1.3-1.8) for men with a family history of nonhematopoietic cancer, and 2.7 (1.9-3.7) for those with a history of hematopoietic cancer among first-degree relatives. This positive association was noted for each group of NHL defined according to the Working Formulation, and was most pronounced for small lymphocytic NHL. Among direct respondents, farmers who used pesticides and had a positive family history of cancer or hematopoietic cancer were not at elevated risk of NHL, compared to nonfarmers who had no family cancer history. However, among proxy respondents, ORs were elevated for farmers who had a positive family history of hematopoietic cancer and used animal insecticides (OR = 4.6; 1.9-11.2), crop insecticides (OR = 4.7; 1.6-13.4), or herbicides (OR = 4.9; 1.7-14.2), although the interaction of family history of cancer and agricultural pesticide use was not statistically significant. In summary, the joint effects of the family cancer history and pesticide use were limited to proxy respondents with wide CIs and, thus, provide little evidence that a family history of cancer modifies the association of agricultural exposures with NHL.  相似文献   
543.
Rearrangements of chromosome band 1p36 in non-Hodgkin's lymphoma.   总被引:2,自引:0,他引:2  
We studied 850 consecutive cases of histologically ascertained pretreatment non-Hodgkin's lymphoma with cytogenetically abnormal clones. The diagnostic karyotypes revealed that 12% of these cases exhibited structural rearrangements involving chromosome band 1p36. Here, we describe the karyotypes of 53 cases containing a 1p36 rearrangement [often involving translocations of unknown material and presented as add(1)(p36)]. We used fluorescence in situ hybridization to determine the origin of the translocation partners. We report three different recurrent translocations involving 1p36. These include der(1)t(1;1)(p36;q21) (three cases), der(1)t(1;1)(p36;q25) (three cases), and der(1)t(1;9)(p36;q13) (four cases). Using cytogenetic and fluorescence in situ hybridization analyses, we have resolved the translocation partners in 31 cases. Rearrangements of band 1p36 were found among different histopathological subtypes. Alterations of 1p36 never occurred as a sole abnormality, and in 42 of 53 cases, alterations of the band 14q32 were observed. The t(14;18)(q32;q21) translocation was present in 35 cases. The significantly high occurrence of 1p36 breakpoint in structural rearrangements and its involvement in recurrent translocations suggest that the region is bearing gene(s) that are important in lymphomagenesis. Our study also showed that cytogenetically evident deletions were frequent in chromosome 1p, almost always involving the p36 region, whereas duplications were rare and never encompassed the p36 region. Chromosome band 1p36 harbors many candidate tumor suppressor genes, and we propose that one or more of these genes might be deleted or functionally disrupted as a molecular consequence of the rearrangements, thus contributing to lymphomagenesis.  相似文献   
544.
Lymphomas arising in mucosa-associated lymphoid tissue (MALT) are indolent B-cell tumors that have a predilection for epithelial sites and often develop in a setting of chronic inflammation or autoimmunity. As many as 50% of low-grade MALT lymphomas contain an (11;18)(q21; q21) chromosomal translocation. Using fluorescence in situ hybridization, we have analyzed the position of recombination within chromosome 18 DNA in three examples of MALT lymphoma bearing this translocation. In all three cases, the breakpoint maps to DNA in BAC b357H2, covering about 150 kb of sequence. A previously undescribed, ubiquitously expressed gene, which we refer to as MALT1, was identified within this sequence and was found to be broken in one case for which we have definitively located the position of recombination between chromosomes 18 and 11. The sequence of this gene indicates the presence of two immunoglobulin-like C2 domains and a region of partial homology to caspases, suggesting a possible role for MALT1 in the regulation of apoptosis.  相似文献   
545.
BACKGROUND Among surgical methods, punch skin grafting (PSG) and suction blister epidermal grafting (SBEG) are simple, inexpensive, and effective treatment methods for resistant lip vitiligo cases, but there is a lack of comparison between these procedures for lip vitiligo.
OBJECTIVE The objective was to compare the outcome following PSG and SBEG in stable lip vitiligo.
METHODS Eighteen patients with stable lip vitiligo were randomly selected. Eight patients were included in PSG group and 10 patients in SBEG. All patients were kept on PUVA-SOL (psoralen+ultraviolet A therapy of solar origin) treatment after grafting. The results were evaluated after a follow-up period of 6 months.
RESULTS At the end of 6 months of grafting in PSG group, two patients had a repigmentation of 50% to 75%, one had 75% to 90%, and three had 90% to 100% in the recipient site in lip. In SBEG group, one patient had repigmentation of 50% to 75%, three had 75% to 90%, and two had 90% to 100%. The color match was statistically significant in PSG when compared to SBEG. In the recipient site, cobblestone appearance was the predominant complication in PSG whereas hyperpigmentation and thickening of grafts were common in SBEG. In the donor site, superficial scarring and hypopigmentation were the common findings in PSG group whereas hyperpigmentation was the main problem in SBEG group.
CONCLUSIONS Although both the procedures are effective in lip vitiligo, PSG gives a better color match than SBEG.  相似文献   
546.
ABSTRACT: Background: Hemorrhage and hypertensive disorders are major contributors to death after delivery in developing countries. The GIRMMAHP Initiative was designed to describe the actual delivery care in five Latin American countries and to educate and motivate clinical staff at 17 hospitals with the purpose of implementing their own clinical practice guidelines to prevent postpartum hemorrhage. Methods: A multicountry education intervention was developed in four consecutive stages, using two analyses: (a) an observational study of the clinical records in eight teaching and nine nonteaching hospitals and (b) a study of the long‐term changes measured 12 months after completion of an education intervention and writing a local clinical guideline. Results: Data from 2,247 pregnant women showed that only 23.3 percent had an active management of the third stage of labor and that 22.7 percent received no prenatal care visit. These data were used to prepare local clinical practice guidelines in each participant hospital. The proportion of active management increased to 72.6 percent of deliveries at 3 months and 58.7 percent 1 year later. Use of oxytocin during the third stage of labor increased to 85.9 percent of included deliveries. The proportion of women who had postpartum hemorrhage decreased from 12.7 percent at baseline to 5 percent at 1 year after the intervention. Conclusions: An education intervention and discussion of actual clinical practice problems with health professionals and their involvement in drafting clinical guidelines helped improve health care quality and practitioners’ adherence to these guidelines. (BIRTH 35:4 December 2008)  相似文献   
547.

Background:

Emergence of polyantimicrobial resistant strains of hospital pathogens has presented a challenge in the provision of good quality in-patient care. Inappropriate use of antibiotics in the hospital is largely responsible for this catastrophe. Bacteriological surveillance of the cases of nosocomial infections is crucial for framing an evidence-based antimicrobial policy for a hospital.

Materials and Methods:

A prospective study was undertaken among 498 patients from medicine and surgery wards in a tertiary teaching hospital in Goa. The patients were followed up clinico-bacteriologically for the occurrence of nosocomial infections (NI). Antibiotic susceptibility testing was done using Kirby-Bauer disc diffusion method.

Results:

The overall infection rate was 33.93 ± 4.16 infections per 100 patients. Urinary tract infection was the most common NI (26.63%), followed by surgical site infection (23.67%), wound infection (23%) and nosocomial pneumonia (18.34%). Ninety-seven percent of the isolates were bacterial, while the others were fungal. More than 80% of the NIs were caused by Gram-negative bacteria, predominantly Pseudomonas aeruginosa, Escherichia coli and Aceinetobacter baumanii. Almost 70% of the isolates were resistant to all the antibiotics for which susceptibility was tested; the rest were sensitive to amikacin, cefoperazone-sulbactam and other antibiotics including methicillin, co-trimoxazole, teicoplenin, vancomycin and rifampicin, either singly or in combination. The proportion of MRSA was 71.4%. Resistance to a particular antibiotic was found to be directly proportional to the antibiotic usage in the study setting.

Conclusion:

Surveillance of nosocomial infections with emphasis on the microbiologic surveillance and frequent antimicrobial audit are critical towards curbing the evil of polyantimicrobial resistant nosocomial infections in a hospital.  相似文献   
548.
Objective  To evaluate the associations between diet and non-Hodgkin lymphoma (NHL) according to t(14;18) status, one of the most common chromosomal abnormalities in NHL, as t(14;18)-positive NHL represents a genetically more homogeneous group than NHL overall. Methods  We determined the presence of the t(14;18)(q32;q21) by fluorescence in situ hybridization in 172 of 175 tumor blocks from a population-based, case–control study conducted in Nebraska during 1983–1986. Information on the frequency of consumption as an adult of 30 food items was derived from the parent case–control study. Dietary factors in 60 t(14;18)-positive and 87 t(14;18)-negative cases were compared with 1,075 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using polytomous logistic regression. Results  The risk of t(14;18)-positive NHL for the highest versus the lowest approximate tertile of intake was elevated for milk (OR = 2.2; 1.0–5.0) and dietary nitrite (OR = 2.8; 1.3–6.1), whereas coffee consumption was inversely associated with risk (OR = 0.4; 0.2–0.7). We also found inverse associations between the intake of fish (OR = 0.5; 0.3–1.0) and carotene (OR = 0.5; 0.2–0.9) and risk of t(14;18)-negative NHL. There was no association between the intake of meats, vegetables, protein, or vitamin C and risk of either t(14;18)-positive or t(14;18)-negative NHL. Conclusion  We observed differences in associations between diet and t(14;18)-defined subgroups of NHL. These findings should be interpreted cautiously because of the small sample. Specific contributions of all authors to published work  B. C. Chiu helped to obtain funding for the project, provided input into the statistical analyses, and drafted and revised this report. B. J. Dave was responsible for molecular cytogenetic data collection and interpretation. S. Jain helped in molecular cytogenetic data analyses. A. Blair, S. H. Zahm, and D. D. Weisenburger designed and conducted the epidemiologic case–control study. M. H. Ward, S. M. Gapstur, A. Blair, A. J. Fought, L. Hou, A. M. Evens, and S. H. Zahm provided input into the data analyses and interpretation. D. D. Weisenburger was responsible for sample collection, and preparation and review of the cases. All authors contributed to the final version of this report.  相似文献   
549.
This study evaluated the outcomes of patients who underwent high-dose chemotherapy (HDC) and autologous hematopoietic stem cell transplantation (autoHSCT) for mantle cell non-Hodgkin's lymphoma and the effect of clinical and treatment characteristics. The clinical outcome and prognostic factors in 40 patients who underwent HDC and autoHSCT for mantle cell lymphoma between June 1991 and August 1998 were analyzed. With a median follow-up of 24 months for the surviving patients (range, 4-68 months), the 2-year overall survival was 65% and the 2-year event-free survival (EFS) was 36%. In univariate analysis, characteristics predictive of a poor EFS were blastic morphology (P = .019) and the patient having received 3 or more prior chemotherapy regimens (P = .004). In a multivariate analysis, the only factor associated with a poor EFS was the number of prior chemotherapy regimens. Those patients who received 3 or more prior therapies had a 2-year EFS of 0%, and those who received <3 therapies had a 2-year EFS of 45% (P = .004). Patients with mantle cell lymphoma can obtain prolonged EFS with HDC and autoHSCT; however, this strategy for prolonged EFS appears to work optimally in patients who are less heavily pretreated. Whether this therapy will increase the overall survival or EFS in patients receiving transplants in first complete remission will need to be tested in prospective randomized clinical trials.  相似文献   
550.
Recent evidence suggests that there is etiologic heterogeneity among the various subtypes of lymphoid neoplasms. However, epidemiologic analyses by disease subtype have proven challenging due to the numerous clinical and pathologic schemes used to classify lymphomas and lymphoid leukemias over the last several decades. On behalf of the International Lymphoma Epidemiology Consortium (InterLymph) Pathology Working Group, we present a proposed nested classification of lymphoid neoplasms to facilitate the analysis of lymphoid neoplasm subtypes in epidemiologic research. The proposed classification is based on the World Health Organization classification of lymphoid neoplasms and the International Classification of Diseases-Oncology, Third Edition (ICD-O-3). We also provide a translation into the proposed classification from previous classifications, including the Working Formulation, Revised European-American Lymphoma (REAL) classification, and ICD-O-2. We recommend that epidemiologic studies include analyses by lymphoma subtype to the most detailed extent allowable by sample size. The standardization of groupings for epidemiologic research of lymphoma subtypes is essential for comparing subtype-specific reports in the literature, harmonizing cases within a single study diagnosed using different systems, as well as combining data from multiple studies for the purpose of pooled analysis or meta-analysis, and will probably prove to be critical for elucidating etiologies of the various lymphoid neoplasms.  相似文献   
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