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51.
BACKGROUND: The adequate control of blood pressure in patients with diabetes mellitus (DM) is important to limit the ocular and systemic complications of the disease. Hypertension in African Americans is among the highest in the world. This cross-sectional study reports the level of blood pressure control in a small sample of African American patients with DM at an urban eye care facility using the criteria defined by the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC VII). METHODS: Five attending faculty members of the Illinois College of Optometry identified 234 African American patients with a diagnosis of DM over a period of 16 months. Blood pressure readings were recorded once at the time of their visit and were classified as controlled or uncontrolled based on the JNC VII cutoff of blood pressure less than 130/80 mmHg. RESULTS: Among the 234 African American patients in this study, 174 (74.4%) reported having DM and hypertension, and 60 (25.6%) reported having DM without hypertension. Of the patients with DM and a self-reported diagnosis of hypertension, 13.2% were controlled. Of the patients with diabetes without a self-reported diagnosis of hypertension, 26.7% were found to be adequately controlled. For the pooled data of 234 patients with diabetes, 16.7% met the JNC VII guidelines. CONCLUSION: The inadequate control of blood pressure in the African American population with DM is associated with increased disability and death from cardiovascular and renal disease. The results of this small cross-sectional study are consistent with those of other studies that show poor control of blood pressure in African American patients who have DM. Preventable blindness secondary to accelerated diabetic retinopathy from uncontrolled hypertension is a concern to all eye care practitioners.  相似文献   
52.
The HER2/neu protooncogene is expressed in the breast, ovarian, gastric and prostatic tumors. Studies done in a number of laboratories have demostrated that 25%–30% of breast cancer contain overexpression of HER2/neu gene. A comparative analysis of the amplification and overexpression of HER2/neu using fluorescencein situ hybridization (FISH) and immunohistochemistry (IHC) was performed to determine the correlation between both techniques. In this study, FISH with HER2/neu probe (Path Vysion) is compared to immunohistochemistry (rabbit anti-human c-erbB-2-DAKO) in a series of 101 prospective human breast cancer specimens. Among 25 patients with score of IHC 3+, 23 (92%) were detected amplified by FISH and in two cases we found overexpression (3+) but without gene amplification. Out of 46 cases with 2+ by IHC, we found 43 not amplified, two moderately amplified (<10 copies) and one highly amplified (>10 copies) (6.5%). No patient with IHC O or 1+, presented amplification of HER2/neu. A good correlation between both techniques was found. FISH technique should have clinical utillity overoat in cases with 2+.  相似文献   
53.
Chromosomal allelic losses have varying frequency in breast cancer, with key regions including chromosomes 1, 3p, 7q, 9p, 16q, 17, and 22q. Recently, we have been able to map a new target region of allelic loss on chromosome 22q involved in colorectal cancer. The aim of the current investigation was to determine whether this target region may also be involved in human breast carcinogenesis. Thirty-six pairs of matched normal and tumor specimens from breast cancer patients, as well as eight breast cancer-derived cell lines, were genotyped using 17 microsatellite markers spanning chromosome 22q. Allelic deletion was found in 19 of 36 tumors (53%), and the pattern observed in those cases with partial losses was consistent with a region flanked by D22S1171 and D22S928. This interval overlaps that identified in colorectal cancer and comprises nearly 1.1 Mb. This study provides evidence of a common region of deletion on chromosome 22q13 involved in both breast and colorectal cancers and underscores the existence of putative tumor suppressor gene(s) at this location.  相似文献   
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Background: This study was performed to prospectively assess the impact of the laparoscopic approach to the patterns of port site metastases (PSM) and recurrence rate (RR) of resected colon carcinomas as compared with conventional colectomies. Methods: All patients were included in a prospective randomized trial comparing laparoscopic-assisted colectomy (LAC) versus open colectomy (OC) for colon cancer. The randomization was stratified for localization of the lesion. Patients with metastasic disease at the time of the surgery were excluded. Follow-up in the outpatient clinic was done every 3 months for a minimum of 12 months. Endpoints for the study were metastasis at port site and laparotomy incision as well as recurrence rate. Results: Of 91 segmental colectomies performed from November 1993 to January 1996, there were 44 LAC and 47 OC. Patient data were similar in both groups (age, sex, Dukes stage, type of operation). Mean follow-up was 21.4 months, with a range of 13 to 41 months. There were no wounds or PSM in those series. RR was similar for both groups. For LAC, it was five of 31 (16.1%); for OC, it was six of 40 (15%). Conclusions: The laparoscopic approach has a recurrence rate similar to that for open procedures for colon cancer. However, additional follow-up of these patients is needed before we can determine whether or not the laparoscopic approach influences overall survival.  相似文献   
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58.
BACKGROUND: Health system delay (HSD) is an important issue in tuberculosis (TB) control. This report investigates HSD and associated factors in a cohort of Spanish culture-confirmed TB patients. METHODS: Data were collected from clinical records. Using logistic regression with two different cut-off points to define HSD (median and 75th percentile), adjusted odds ratios were used to estimate the association between HSD and different variables. RESULTS: A total of 5184 culture-confirmed TB cases were included. Median and 75th percentile HSD were 6 and 25 days respectively. HSD significantly greater than the median was associated with: age >44 years, past or present intravenous drug use, diagnosis at a primary-care centre, prior preventive therapy, positive histology, request for drug-sensitivity testing, presence of silicosis or neoplasia in addition to TB, presence of non-TB related symptoms, and gastrointestinal site. HSD greater than the 75th percentile was related to the same variables, with the exception of diagnosis at a primary-care centre, positive histology, silicosis, non-TB-related symptoms and gastrointestinal site, for which the association disappeared; in contrast, an association with female gender emerged. CONCLUSION: Despite free health care being universally available in Spain, there are some groups of TB patients whose treatment is unduly delayed.  相似文献   
59.
BACKGROUND: Prognostic models need to be tested in external validation studies to assess generalizability. Recursive partitioning analysis (RPA), a prognostic system based on the creation of a classification tree, has been proposed as a classification method in patients with head and neck carcinoma. The aim of this study was to compare the RPA and Union Internationale Contre le Cancer (UICC) TNM classification systems in patients with head and neck carcinoma treated consecutively in a single center. METHODS: A total of 2166 patients with carcinomas of the oral cavity, oropharynx, hypopharynx, and larynx was classified according to both the RPA and the TNM classification systems, and the results were compared. The endpoints considered were observed survival and survival free of locoregional tumor. The two methods of classification were evaluated objectively by use of measures of intrastage homogeneity (hazard consistency), interstage heterogeneity (hazard discrimination), predictive power (outcome prediction), and patient distribution between stages (balance). RESULTS: When the endpoint considered was observed survival, there were no clinically relevant differences between the two classifications. However, when the endpoint was locoregional control, the RPA system was sensitive to the type of treatment used, and it was not generalizable. CONCLUSIONS: To evaluate generalizability, new classification proposals need external validation studies that objectively measure the quality of the model. The performance of the RPA system was not reproducible in our cohort of patients when the endpoint evaluated was locoregional control.  相似文献   
60.
We investigated the expression of choline acetyltransferase, a specific marker for cholinergic neurons, in control and spinal muscular atrophy fetuses and newborns. By immunoblot we observed at 12 and 15 weeks a similar pattern of choline acetyltransferase expression in spinal muscular atrophy with respect to controls, although at 22 weeks this expression was reduced, probably due to a smaller number of motor neurons in the spinal muscular atrophy spinal cord. By immunohistochemistry, the counting of positive and negative motor neurons for choline acetyltransferase immunostaining in control and spinal muscular atrophy fetuses showed a similar proportion at all stages analyzed. The choline acetyltransferase-negative motor neurons were of similar appearance in both groups. After birth, chromatolytic motor neurons were detected in spinal muscular atrophy, all of which were choline acetyltransferase-negative. Our results in spinal muscular atrophy fetuses indicate that choline acetyltransferase immunostaining does not identify early events in neuronal pathogenesis and suggest that the spinal muscular atrophy surviving motor neurons may not be dysfunctional during this period. Furthermore, spinal muscular atrophy choline acetyltransferase-negative motor neurons showed detectable pathological changes only after birth, indicating that choline acetyltransferase is a late marker for motor neuron degeneration and not a primary contributing factor in this process.  相似文献   
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