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61.
Since coronary heart disease (CHD) is the leading cause of death in American women it is therefore likely the leading cause of death among lesbians. Prevention of CHD is a major health issue for lesbians. Efforts must continue to empower all lesbians to take personal preventative action to prevent CHD. Women in general do not believe they are at risk for CHD. A common misperception is that CHD is a man's disease and the most likely threat to a woman's life is breast cancer. This misperception probably exists among lesbians as well. Over a lifetime, a woman is 10 times more likely to develop CHD than she is breast cancer. Breast cancer remains an important health concern for woman, but CHD risk must be addressed with potent educational and advocacy programs for the health of our communities. Prevention of the clinical manifestations of CHD hinges upon the prevention of plaque formation. It is an obligation of primary care providers to give advice regarding the prevention of plaque formation and therefore the prevention of subsequent CHD events and to collaborate with patients to address these issues in an individually tailored manner. This review addresses risk factors for CHD in lesbians to assist providers in achievement of that goal.  相似文献   
62.
Background. Prior studies of recall accuracy for screening mammogram behavior have examined relatively homogeneous groups. Data are limited on possible systematic group differences, so we evaluated women's recall accuracy in two separate care systems in one city.Methods. Women 50 to 70 years old with and without screening mammograms 10 to 14 months prior were identified from fiscal, clinic, and radiology records at a military care system (MCS) and a county-funded system (CFS) for indigents. Mammogram status was verified through radiology records. Women were excluded if mammograms were diagnostic, done for other than annual screening, or had abnormal results. Interview ers blinded to mammogram status surveyed randomly selected eligible women.Results. For 62 screened/31 unscreened MCS women and 78 screened/61 unscreened CFS women, specificity was similar, at 65 and 62%, respectively. In contrast, sensitivity varied significantly: 95% versus 79% (P = 0.011). Primary ethonocultural groups were Euro-American (MCS—60%) and Mexican American (CFS—85%). Although not different in specificity of recall (67% versus 61%), these major subgroups significantly differed in sensitivity (97% versus 80%, P = 0.017), proportion of true negatives due to never having a mammogram (35% versus 57%, P = 0.003), and proportion with ≥high school education (78% versus 19%, P < 0.00001).Conclusion. Systematic differences in recall validity may exist and compromise the accuracy of intergroup comparisons.  相似文献   
63.
Rationale: Facial expressions appear to be processed by at least partially separable neuro-cognitive systems. Given this functional specialisation of expression processing, it is plausible that these neurocognitive systems may also be dissociable pharmacologically. Objective: The present study therefore compared the effects of diazepam (15 mg) with placebo upon the ability to recognise emotional expressions. Methods: A double blind, independent group design was used to compare the effects of diazepam and matched placebo in32 healthy volunteers. Participants were presented morphed facial expression stimuli following a paradigm developed for use with patients with brain damage and asked to name one of the six basic emotions (sadness, happiness, anger, disgust, fear and surprise). Results: Diazepam selectively impaired subjects’ ability to recognise angry expressions but did not affect recognition of any other emotional expression. Conclusions: The findings are interpreted as providing further support for the suggestion that there are dissociable systems responsible for processing emotional expressions. It is suggested that these findings may have implications for understanding paradoxical aggression sometimes elicited by benzodiazepines. Received: 27 May 1999 / Accepted: 7 July 1999  相似文献   
64.

Purpose

This case report presents a patient with Emery-Dreifuss Muscular Dystrophy and describes the anaesthetic considerations.

Clinical features

The features of Emery-Dreifuss Muscular Dystrophy are contractures, humeroperoneal muscle weakness and cardiomyopathy. The anaesthetic considerations for this syndrome are difficult tracheal intubation, difficult spinal anaesthetic, heart block, gastric reflux, rhabdomyolysis, and unproved malignant hyperthermia susceptibility.

Conclusion

The major anaesthetic problem for the patient with Emery-Dreifuss Muscular Dystrophy could be a life-threatening cardiomyopathy.  相似文献   
65.
Objectives. Mexican Americans (MAs), compared to white non‐Hispanics (WNHs), have higher rates of biliary disease, noninsulin dependent diabetes, and endstage renal disease but lower rates of lung cancer, hip fractures, and mortality from coronary heart disease. Relatively little research has been done to identify other ethnic differences in disease incidence. We used surgical procedure rates to confirm known ethnic differences and to explore our clinical suspicion that MAs have higher rates of appendectomy than WNHs.

Methods. We used a registry of surgical procedures at two teaching hospitals in South Texas to calculate proportional operation ratios (PORs) for MAs versus WNHs. These two hospitals are the primary source of acute hospital care for the indigent in the area. The POR is arithmetically identical to proportional incidence and mortality ratios.

Results. MAs underwent appendectomy proportionally more often than WNHs at both hospitals (POR = 1.41 and 1.75, p < 0.0001). Other significant PORs were consistent with known ethnic disease differences in biliary tract operations, vascular access for chronic hemodialysis, lung cancer, and coronary artery bypass.

Conclusions. These findings support the hypothesis that MAs may undergo appendectomy more often than WNHs and so may be at higher risk of appendicitis.  相似文献   

66.
The occurrence of preferential repair in Saccharomyces cerevisiaeof the active MAT locus compared with the inactive HML locuswas confirmed after 254 nm UV irradiation. Experiments carriedout using the UvrABC excinuclease assay with the monofunctionalfurocoumarin 3-carbethoxypsoralen (3-CPs) plus UVA radiationwhich induce mainly monoadducts in DNA demonstrated preferentialrepair of the active MAT locus compared with the inactive HMLlocus in a SIR+ strain. However, as after 254 nm UV irradiation,no difference in the rate of removal of 3-CPs plus UVA inducedlesions was observed between the two loci in the sir-3 mutantin which both loci are active. Thus, it appears that 3-CPs plusUVA induced monoadducts as well as pyrimidine dinners a e subjectto preferential repair. 3To whom correspondence should be addressed  相似文献   
67.
The purpose of this study was to evaluate the stability of the arterial PCO2 (PaCO2) to end-tidal PCO2 (PETCO2) partial pressure difference (Pa-ETCO2) during surgery using PETCO2 monitoring, in children with congenital heart disease (CHD). Forty children with CHD were studied: ten children with no interchamber communication and normal pulmonary blood flow (PBF) (normal group); ten acyanotic children with increased PBF (acyanotic-shunting group); ten cyanotic children with mixing type lesions and normal or increased PBF (mixing group), and ten cyanotic children with right-to-left intracardiac shunts demonstrating decreased and variable PBF (cyanotic-shunting group). Simultaneous PaCO2 recordings and PETCO2 measurements were obtained for each patient during five intraoperative events: (1) control time, arterial line placement under anaesthesia; (2) time 1, patient preparation; (3) time 2, immediately after sternotomy; (4) time 3, after heparin administration; and (5) time 4, immediately after aortic cannulation. Initially, cyanotic children demonstrated a greater Pa-ETCO2 compared with acyanotic children (P less than 0.05). There was no difference in the Pa-ETCO2 over time in the control, acyanotic-shunting, or mixing groups. The Pa-ETCO2 in the children with cyanotic-shunting lesions at times 2 and 3 was greater (P less than 0.05) than at their control times. We conclude that the Pa-ETCO2 of children with acyanotic-shunting and mixing congenital heart lesions is stable intraoperatively, although patients with mixing congenital heart lesions may demonstrate large individual variations. In children with cyanotic-shunting congenital heart lesions, the Pa-ETCO2 is not stable. The PETCO2 cannot be used during surgery to estimate reliably the PaCO2 in children with cyanotic CHD.  相似文献   
68.
Abstract: Earlier work in this laboratory showed that amiodarone induces apoptosis in alveolar epithelial cells by a mechanism inhibitable by angiotensin system antagonists. A variety of recent studies suggests a critical role for alveolar epithelial cell apoptosis in the pathogenesis of lung fibrosis. On this basis we hypothesized that amiodarone‐induced alveolar epithelial cell apoptosis and lung fibrosis in vivo might be inhibitable by the angiotensin converting enzyme inhibitor captopril or the angiotensin receptor antagonist losartan. Amiodarone‐induced lung fibrosis was induced in male Wistar rats by oral adminstration over six months. Replicate groups of rats received captopril or losartan in addition to amiodarone. Apoptosis was detected by increased total lung activity of caspase 3 and in situ end labeling (ISEL) of fragmented DNA. Collagen was localized and quantitated by the picrosirius red technique. Alveolar epithelial cell apoptosis was detected in amiodarone‐treated animals as early as three weeks after the start of amiodarone administration; by six months exposure, the incidence of alveolar epithelial cell apoptosis was significantly reduced by coadministration of captopril or losartan. Alveolar wall collagen accumulation also was significantly attenuated by captopril (100%) or losartan (74%), but neither agent blunted the accumulation of alveolar macrophages evoked by amiodarone (5.3‐fold at 6 months). Lung neutrophil content was unchanged by amiodarone treatment for three weeks or six months. These results indicate that amiodarone induces alveolar epithelial cell apoptosis in vivo that is inhibitable by angiotensin antagonists. They also support the hypothesis that blockade of angiotensin formation or function attenuates amiodarone‐induced lung fibrosis irrespective of the severity of alveolitis.  相似文献   
69.
PURPOSE: In recent years, the incidence of cutaneous melanoma has increased more than that of any other cancer. Dacarbazine is considered the gold standard for treatment, having a response rate of 15% to 20%, but most responses are not sustained. Previously, we have shown that short exposure of primary cutaneous melanoma cells to dacarbazine resulted in the upregulation of interleukin-8 (IL-8) and vascular endothelial growth factor (VEGF). The purpose of the present study was to determine how long-term exposure of melanoma cells to dacarbazine would affect their tumorigenic and metastatic potential in vivo. MATERIALS AND METHODS: The primary cutaneous melanoma cell lines SB2 and MeWo were repeatedly exposed in vitro to increasing concentrations of dacarbazine, and dacarbazine-resistant cell lines SB2-D and MeWo-D were selected and examined for their ability to grow and metastasize in nude mice. RESULTS: The dacarbazine-resistant cell lines SB2-D and MeWo-D exhibited increased tumor growth and metastatic behavior in vivo. This increase could be explained by the activation of RAF, MEK, and ERK, which led to the upregulation of IL-8 and VEGF. More IL-8, VEGF, matrix metalloproteinase-2 (MMP-2), and microvessel density (CD-31) were found in tumors produced by SB2-D and MeWo-D in vivo than in those produced by their parental counterparts. No mutations were observed in BRAF. CONCLUSION: Our results have significant clinical implications. Treatment of melanoma patients with dacarbazine could select for a more aggressive melanoma phenotype. We propose that combination treatment with anti-VEGF/IL-8 or MEK inhibitors may potentiate the therapeutic effects of dacarbazine.  相似文献   
70.
PURPOSE: Homozygous deletions at chromosome region 9p21 targeting the CDKN2A gene have been reported as a common cytogenetic abnormality in mesothelioma. MTAP, a gene approximately 100-kb telomeric to CDKN2A, encodes methylthioadenosine phosphorylase, an enzyme essential in the salvage of cellular adenine and methionine, and its codeletion with CDKN2A has been reported in other tumors. The aim of this study was to define the prevalence of homozygous deletion of CDKN2A alone or in combination with MTAP in a large series of pleural mesothelioma. EXPERIMENTAL DESIGN: We used a fluorescent in situ hybridization assay for CDKN2A and MTAP on interphase nuclei in imprints of frozen tissue from 95 cases of pleural mesothelioma. Histologically, the cases were classified as epithelial (71), biphasic (19) and sarcomatous (5). In each experiment, a 9p21 locus specific probe and a chromosome 9 centromeric probe were used and fluorescent in situ hybridization signals for both probes were simultaneously recorded in at least 100 nuclei. Cases were considered homozygously deleted if both 9p21 signals were lost in at least 20% of nuclei. RESULTS: Overall, 70 cases (74%) had homozygous deletion of CDKN2A. MTAP was codeleted in 64 of these cases (91%). No case with MTAP deletion without CDKN2A deletion was identified. Homozygous loss of CDKN2A was seen in 49 of 71 epithelial (70%), 16 of 19 biphasic (89%), and 5 of 5 sarcomatous (100%) mesotheliomas. CONCLUSIONS: Homozygous deletion of CDKN2A is seen in the majority of pleural mesotheliomas, and MTAP is codeleted in most of these cases. Previous cell line studies have shown that loss of MTAP renders cells dependent on de novo synthesis of purine derivatives. Thus, the particularly high prevalence of MTAP codeletion in mesothelioma makes it an ideal candidate for trials of targeted therapy using inhibitors of de novo AMP synthesis (e.g., L-alanosine).  相似文献   
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