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81.
Anne M. Weber MD Allison R. Mitchinson MPH Gita P. Gidwani MD Edward Mascha MS Mark D. Walters MD 《American journal of obstetrics and gynecology》1997,176(6):1213-1219
OBJECTIVE: Our purpose was to describe clinical characteristics in premenopausal women with uterine myomas and to identify factors associated with hysterectomy.STUDY DESIGN: Data were collected by chart abstraction in 421 premenopausal women with myomas and analyzed by univariate and multivariable regression.RESULTS: Over a median follow-up period of 29 months, 86% of women had symptoms associated with myomas and 40% had an increase in uterine size of >2 gestational weeks. By multivariable regression, bleeding symptoms at presentation and previous surgical history of cholecystectomy and adhesiolysis were significantly associated with greater odds of hysterectomy. There was a significant interaction between age and uterine size, so that as age increased, uterine size had a greater impact on the likelihood of hysterectomy.CONCLUSIONS: In this cohort of premenopausal women myomas were associated with symptoms in almost all women over the follow-up period. Hysterectomy was performed in 22% of women overall. (Am J Obstet Gynecol 1997;176:1213-9.) 相似文献
82.
Increased placental apoptosis in intrauterine growth restriction 总被引:2,自引:0,他引:2
Stephen C. Smith MB ChB Philip N. Baker DM E.Malcolm Symonds MD 《American journal of obstetrics and gynecology》1997,177(6):1395-1401
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401) 相似文献
83.
Associations of substance use, abuse, and dependence with subsequent suicidal behavior 总被引:5,自引:0,他引:5
General population survey data are used to disaggregate the associations of substance use disorders with suicide attempts in order to evaluate a number of hypotheses about the processes leading to these associations. Data are from the US National Comorbidity Survey (1990-1992). Discrete-time survival analysis is used to study the effects of retrospectively reported temporally prior substance use, abuse, and dependence in predicting first onset of suicidal behavior. Alcohol and drug use predict subsequent suicide attempts after controlling for sociodemographics and comorbid mental disorders. Previous use is not a significant predictor among current nonusers. Abuse and dependence are significant predictors among users for three of the 10 substances considered (alcohol, inhalants, and heroin). The number of substances used is more important than the types of substances used in predicting suicidal behavior. Disaggregation shows that the effects of use are largely on suicidal ideation and nonplanned attempts among ideators. In comparison, the effects of use on suicide plans and planned attempts among ideators are not significant. Clinicians need to be aware that current substance use, even in the absence of abuse or dependence, is a significant risk factor for unplanned suicide attempts among ideators. 相似文献
84.
Heating and pain sensation produced in human skin by millimeter waves: comparison to a simple thermal model 总被引:7,自引:0,他引:7
Cutaneous thresholds for thermal pain were measured in 10 human subjects during 3-s exposures at 94 GHz continuous wave microwave energy at intensities up to approximately 1.8 W cm(-2). During each exposure, the temperature increase at the skin's surface was measured by infrared thermography. The mean (+/- s.e.m.) baseline temperature of the skin was 34.0+/-0.2 degrees C. The threshold for pricking pain was 43.9+/-0.7 degrees C, which corresponded to an increase in surface temperature of approximately 9.9 degrees C (from 34.0 degrees C to 43.9 degrees C). The measured increases in surface temperature were in good agreement with a simple thermal model that accounted for heat conduction and for the penetration depth of the microwave energy into tissue. Taken together, these results support the use of the model for predicting thresholds of thermal pain at other millimeter wave (length) frequencies. 相似文献
85.
86.
PURPOSE: We quantified the agreement between the underlying cause of death determination from information in hospital medical records and on death certificates, and determined whether the frequency of assigning death from prostate cancer had changed since the introduction of testing for prostate specific antigen. MATERIALS AND METHODS: We retrospectively reviewed and analyzed the information in hospital medical records and on death certificates for men previously diagnosed with prostate cancer who died in 1985 or 1995. RESULTS: The underlying cause of death determinations from a review of 201 hospital medical records agreed with those from information on part 1 of the death certificate in 87% of cases and with those using the International Classification of Diseases-9 system coding rules in 80%. Agreement was higher in men who were older than those who were younger at the time of death, and higher in those diagnosed with prostate cancer several years before death than in those diagnosed shortly before death. CONCLUSIONS: There was a high level of agreement concerning the underlying cause of death after a review of the information in hospital medical records and on death certificates for men with prostate cancer when cause of death was viewed as a dichotomous variable. The International Classification of Diseases-9 coding rules concerning the underlying cause of death favor overreporting rather than underreporting prostate cancer deaths compared with a review of hospital medical records. Cause of death determination does not appear to have changed after the introduction of prostate specific antigen testing. 相似文献
87.
Mark C. Walters 《Pediatric transplantation》2004,8(S5):33-38
Abstract: Hematopoietic cell transplantation (HCT) is curative therapy for sickle cell anemia (SCA). However, its widespread use is constrained by donor availability and by concerns about its short-term and long-term toxicities. Current efforts to identify suitable candidates for HCT, to decrease the toxicity of HCT, and to broaden its availability are discussed. 相似文献
88.
背景与目的:感染丙型肝炎病毒(HCV)的肝移植受体在肝移植术后很快进展为复发性肝炎,其中一些患在术后2年内即进展为肝纤维化。该项研究目的是识别影响肝脏疾病进展的分子机制,并寻求早期肝纤维化可能的基因标志物。方法:作对13例(11例感染和2例非感染)肝移植受体,分别在其移植术后1年之内的0、3个月、6个月和12个月对其肝活检标本进行连续性基因表达分析。将所得数据与临床观察结果进行比较,并与从55例非移植的丙型肝炎感染和非感染的肝脏活检标本获得的基因表达数据库进行比较。结果:识别出一些特殊的基因表达模式。第1种模式是移植受体所特有的,而与其是否存在感染无关,其相应的基因编码应激反应蛋白和涉及凝血的血蛋白,在移植术后移植物的恢复中有差异性表达;第2种模式为HCV感染所特有的,包括编码干扰素介导的抗病毒反应和免疫系统(抗原递呈,细胞毒反应)基因编码元件上调,而这些上调表达在进展为早期纤维化的患体内缺失或被抑制,从而提示患疾病的进展可能是由于肝脏对感染的反应受损所致;最后一种基因表达模式,是4例感染了HCV并进展为早期肝纤维化的患第12个月的肝活检标本所特有的。 相似文献
89.
90.