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41.
Increased placental apoptosis in intrauterine growth restriction   总被引:2,自引:0,他引:2  
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   
42.
Trastuzumab-associated cardiotoxicity   总被引:9,自引:0,他引:9  
Keefe DL 《Cancer》2002,95(7):1592-1600
Trastuzumab is a monoclonal antibody used for the treatment of metastatic breast carcinoma in women whose tumors overexpress the HER2 protein. Cardiotoxicity has been reported to occur with trastuzumab when administered alone and in combination with antineoplastic agents, particularly anthracyclines. The risk of cardiotoxicity with trastuzumab has been reported to be 4% with monotherapy and 27% when administered in combination with an anthracycline and cyclophosphamide, but to the author's knowledge severe outcomes, such as death or permanent disability, are uncommon. The majority of reported cardiac effects are mild to moderate, nonspecific, and medically manageable. Signs and symptoms are similar to those observed in patients who develop anthracycline-induced cardiomyopathy and include tachycardia, palpitations, and exertional dyspnea, which may progress to congestive heart failure. The pathogenesis and histologic changes responsible for trastuzumab-associated cardiotoxicity currently are under investigation. Unlike anthracycline-induced toxicity, trastuzumab-associated toxicity usually responds to standard treatment or the discontinuation of trastuzumab, and there is no evidence that the toxicity is dose related. Current methods for the early detection of cardiotoxicity in trastuzumab-treated patients are similar to those used in anthracycline-treated patients. Cardiac function is established at baseline and monitored regularly during treatment by physical examination and measurement of left ventricular ejection fraction. The majority of patients improve with proper treatment, and some are able to continue to receive trastuzumab.  相似文献   
43.
Fistulation between the trachea and an infected mucocele arising from an excluded retained esophageal segment is an interesting and unusual complication of esophageal bypass surgery. We present such a case in which there was also malignant transformation in the cyst wall, manifested by invasive adenocarcinoma and widespread high-grade glandular dysplasia.  相似文献   
44.
Recognition and correction of septal abnormalities in rhinoplastic surgery has been a constant evolution aided by the development of an in depth anatomic understanding of the nose and the refinement of techniques based on the pertinent anatomy. Whether the deformity presents a functional, aesthetic, or combined problem, the authors prefer a single stage technique that separates the structural components of the nose, isolating the deformities present, and then reconstructing the components to effect a desirable result in terms of airway and appearance. Although no two nasal surgeries are identical, there are characteristic deformities that are noted to be generally more problematic. We briefly review normal septal anatomy as it pertains to the septorhinoplasty operation and then discuss our approach to specific septal variations that we have found to have a significant impact with regard to achieving satisfactory functional and aesthetic results.  相似文献   
45.
OBJECTIVE: To evaluate how well polar body location predicts spindle localization and to examine spindle morphology. DESIGN: Randomized, controlled animal study. SETTING: University-affiliated research laboratory. ANIMAL(S): Mature, female golden hamsters. INTERVENTION(S): After superovulation with pregnant mare serum gonadotropin and hCG, metaphase II oocytes were obtained and imaged under digital polarization microscopy. MAIN OUTCOME MEASURE(S): Identify the meiotic spindle in living, unfixed hamster oocytes and determine spindle location relative to the polar body. RESULT(S): Spindles were imaged in 30 oocytes and only in 5 of them could the polar body predict the spindle localization. In the remaining oocytes, the spindles presented a random distribution within the cytoplasm. CONCLUSION(S): These data show that the polar body location is not an accurate predictor for meiotic spindle location in mammalian oocytes.  相似文献   
46.
High serum insulin and lipoproteins have been reported in pregnancy-induced hypertension. Little is known about the insulin and lipoprotein profile in Indian women. To address this question we compared serum insulin and lipoproteins of women with pregnancy induced hypertension (PIH) and normotensive pregnant women. The serum insulin, triglycerides, total cholesterol and HDL cholesterol of 104 women with PIH were compared with 99 control women. Hypertensive women had significantly higher insulin (53.94 +/- 29.58 versus 37.69 +/- 17.39 pmol/L, p=0.0004) and triglyceride (3.27 +/- 1.2 versus 2.66 +/- 0.6, p=0.0001). There was no significant difference in total cholesterol and HDL cholesterol levels. Insulin levels had a positive correlation with systolic blood pressure (r=0.64) and diastolic blood pressure (r=0.55) in women with PIH. These differences persisted even after adjusting for possible confounding variables such as age, body mass index and the period of gestation. We conclude that elevated serum insulin values or insulin resistance may contribute to the pathogenesis of PIH in Indian women.  相似文献   
47.
This article presents a brief review of the effects of inhaled corticosteroids on growth in children with asthma. All currently available inhaled corticosteroids, where there is adequate data, have been shown to cause significant growth suppression in children in a dose-dependent manner. It is now apparent that there are differences in the growthsuppressive effects of different corticosteroids. Recent evidence confirms that the growth-suppressive effects are short lived and that, at conventional doses, inhaled corticosteroids do not affect final attained adult height.  相似文献   
48.
49.
We describe a case of papuloerythroderma. This is a distinctive clinical entity characterized by pruritus, red-brown flat-topped papules exhibiting the "deck-chair" sign, eosinophilia, and lymphopenia. We propose that the Langerhans cell may have a central role in the pathogenesis of papuloerthroderma and we describe an excellent response to photochemotherapy.  相似文献   
50.
Platelet membrane fluidity in Alzheimer's disease and major depression   总被引:5,自引:0,他引:5  
Double-blind fluorescence studies of platelet membrane fluidity were conducted at 37 degrees C for 51 patients with Alzheimer-type dementia, 24 nondemented depressed patients, and 50 neurologically healthy subjects. The fluidity of the hydrocarbon region of platelet membranes from the demented group, as reflected by the steady-state anisotropy of the fluorescent probe 1,6-diphenyl-1,3,5-hexatriene (DPH), was significantly greater than that for the depressed and normal control subjects. Within the demented group, platelet membrane fluidity was significantly correlated with severity of dementia but not with duration of illness or age at onset. Demented patients with "increased" platelet membrane fluidity had an earlier onset, were more severely demented, and deteriorated more rapidly.  相似文献   
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