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921.
922.
LeRoy SS 《AACN clinical issues》2001,12(1):87-99
Innovations in surgical and medical treatment continue to improve the outlook for children with complex congenital heart disease. Although mortality continues to decrease, disease-related morbidity is increasing as a large cohort of these patients is reaching young adulthood, pursuing careers, marrying, and in many cases having children of their own. Chronic recurrent dysrhythmias are a frequent cause of long-term morbidity in this population and result in frequent, unanticipated emergency room visits and hospitalizations. Although not usually life threatening, they can pose considerable challenges to the patients and the providers who care for them. This article provides an overview of the most common dysrhythmias encountered in this population, dysrhythmia substrates, and therapeutic options. 相似文献
923.
The fingers of 75 patients with connective tissue disorders were examined by “wide-field” capillary microscopy. Four diagnostic groups were included in this study: rheumatoid arthritis—28, scleroderma—22, dermatomyositis—8, and systemic lupus erythematosus—17.On the basis of different patterns of elementary microvascular abnormalities and their distribution, 3 distinct groups were recognized among these patients: 1) increased visibility of nailfold subpapillary plexus in rheumatoid arthritis, 2) massive capillary dilatation in scleroderma-dermatomyositis, and 3) focal loss of capillaries and prominence of subpapillary vessels with “punched-out” lesions in systemic lupus erythematosus. 相似文献
924.
Stark DD; Wittenberg J; Edelman RR; Middleton MS; Saini S; Butch RJ; Brady TJ; Ferrucci JT Jr 《Radiology》1986,159(2):365-370
Forty-three patients with liver metastases were imaged using 14 different pulse sequences (average, 7.5 sequences per patient) to allow direct comparison of their performance. "T2-weighted" spin-echo (SE) images, "T1-weighted" inversion recovery (IR) images, and "T1-weighted" SE images were obtained using a wide range of timing parameters. Pulse sequence performance was quantitated by measuring liver signal-to-noise (S/N) ratios and cancer-liver signal difference-to-noise (SD/N) ratios. Data were standardized to reflect a constant imaging time of 9 minutes for all pulse sequences. The SE 2,000/120 (TR [repetition time]/TE [echo time]) sequence resulted in the greatest SD/N ratio of the T2-weighted SE sequences but also yielded the low S/N ratios, poor anatomic resolution, and motion artifacts common to all T2-weighted SE images. IR sequence images were also sensitive to motion artifacts because of the use of a long TR (1,500 msec). Short TR/TE T1-weighted SE sequences (SE 260/18) had the greatest SD/N ratio (P less than .05), S/N ratio, and anatomic resolution. Furthermore, extensive signal averaging appears to be a powerful solution to all types of motion artifacts in the abdomen. 相似文献
925.
This article has discussed the increased incidence and disproportionately increased mortality of prostate cancer among African American men.Although the exact reasons are unknown, genetics may play a role, in addition to health care practices. Morbidity from other disease states, such as diabetes, obesity, or hypertension, may influence the overall survival of patients with prostate cancer. Current research tools will continue to explore biologic differences between the races; however, socioeconomic status and access to health care must not be overlooked. Several studies have demonstrated that similar disease stages and equal access to health care will result in similar outcomes.It is recognized that screening for prostate cancer will remain a controversial topic. Several influential professional societies recommend against screening and other professional societies endorse screening. Large-scale trials are currently underway hoping to answer this critical question.Since the advent of current screening tools, however, it seems that the overall mortality for prostate cancer has decreased and this cannot be ignored. Certainly, screening programs and clinical trials have traditionally had difficulty in recruiting minority participants, although more recent trials seem to be finding success. A primary care physician who is viewed as competent by their patients can certainly have a positive impact on their African American patients' willingness to participate in studies and screening programs. Most importantly, on the individual level, primary care physicians can provide a great service to their minority patients by offering educational materials on prostate cancer and by offering screening to qualified patients. The current American Urologic Association and National Cancer Institute guidelines recommend offering screening to all men age 50 and above. African American men or men with a first-degree relative with prostate cancer should be offered screening beginning at age 40.Proper screening consists of both a digital rectal examination to assess for asymmetry or nodules of the prostate and a serum PSA. Current recommendations are that individuals with a serum PSA greater than 4 ng/mL ora prostate nodule or asymmetric prostate should be referred to an urologist,where a biopsy can be performed easily in the office setting.The PSA cutoff of 4 has recently been questioned. A study by Thompson et al [31] evaluated 2950 men with a PSA of 4 or less with prostate biopsy.They found that the risk of prostate cancer in men with a PSA between 3.1 and 4 was 26.9% and that 25% of these men with prostate cancer had high-grade disease. All men found to have cancer had T1 disease. The clinical relevance of this surprisingly high rate of prostate cancer in men with a normal PSA is yet to be determined and is pending in studies on the ultimate effect of screening on mortality from prostate cancer. This information is not intended to confuse the issue, but intended to provide the most up-to-date information and allow for the best clinical decision making by the primary care physician. What can currently be recommended is if a patient is concerned about his possibility of having prostate cancer despite a normal PSA, a referral to an urologist to at least further discuss the issue may be in order. This may be especially true if the patient is African American or has a family history of prostate cancer at an early age. 相似文献
926.
TJ Peters 《Journal of clinical pathology》1983,36(2):241-242
927.
M Levin KB Elkon TJ Nokes AM Buckle MJ Dillon RM Hardisty TM Barratt 《Archives of disease in childhood》1983,58(9):703-708
Prostacyclin (PGI2) production was diminished when rat aortic rings were incubated with plasma from 5 of 6 patients with the sporadic form of haemolytic uraemic syndrome but was normal in the presence of plasma from 7 patients with the epidemic form of haemolytic uraemic syndrome or from patients with other renal diseases. The reduced PGI2 production was caused by an unstable inhibitor, extractable into polar lipid solvents, in sporadic haemolytic uraemic plasma. These results suggest that there may be at least 2 different pathogenetic mechanisms in epidemic and sporadic haemolytic uraemic syndrome and that the reduced PGI2 production observed in the sporadic type is due to an inhibitor of PGI2 production rather than a deficiency of stimulating factors. 相似文献
928.
The intake of nutrients over a five day period was studied in 23 children whose atopic eczema was being treated by the avoidance of multiple foods. The results were compared with those from 23 healthy control children not on a diet. Significantly low intakes of calcium were discovered in 13 patients but not in controls. Avoidance of multiple foods is potentially hazardous and requires continued paediatric and dietetic supervision. 相似文献
929.
Shigemasa K Tanimoto H Sakata K Nagai N Parmley TH Ohama K O'Brien TJ 《Medical oncology (Northwood, London, England)》2000,17(1):52-58
Matrix metalloproteases are known to play an important role in tumor invasion by mediating degradation of the extracellular
matrix. In this study, we have investigated the immunohistochemical expression of matrix metalloprotease-7 (MMP-7) in 44 mucinous
ovarian tumors (9 adenomas, 13 low malignant potential tumors, 22 adenocarcinomas) and 6 normal ovaries. Positive staining
of MMP-7 is observed in all mucinous ovarian tumors, whereas little or no staining was observed in surface epithelium as well
as the epithelial cells of germinal inclusion cyst of the normal ovary. Positive immunostaining of MMP-7 is also observed
in the secreted mucin in the tumor glands, which suggests the secretion of the MMP-7 protein from tumor cells. mRNA expression
of MMP-7 was confirmed using RT-PCR. The MMP-7 gene was amplified in parallel with an internal control gene β-tubulin using
a thermal cycler. mRNA expression levels of MMP-7 were significantly elevated in mucinous tumor samples compared with that
in normal ovaries. Our results suggest that MMP-7 is frequently overexpressed in mucinous ovarian tumors and secreted with
the mucin which is produced from the tumor cells. MMP-7 may therefore contribute to mucinous ovarian tumor development or
enhanced growth capacity of mucinous ovarian tumors. MMP-7 may also serve as a target for therapeutic intervention in the
down regulation of tumor progression. 相似文献
930.
Lower esophageal sphincter pressures and serum gastrin levels after cholinergic stimulation 总被引:2,自引:0,他引:2
Higgs RH; Humphries TJ; Castell DO; McGuigan JE 《The American journal of physiology》1976,231(4):1250-1253