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21.
Jacob Rabinson Itai Bar-Hava Simion Meltcer Efraim Zohav Eyal Anteby Raoul Orvieto 《Gynecological endocrinology》2006,22(4):175-178
OBJECTIVE: To evaluate the influence of gravidity on the results of in vitro fertilization (IVF)-embryo transfer (ET) cycles. PATIENTS AND METHODS: All consecutive women aged <35 years admitted to our IVF unit from January 2002 to December 2004 were enrolled in the study. Only patients undergoing one of their first three IVF cycle attempts were included. Gravidity, ovarian stimulation characteristics, number of oocytes retrieved, number of embryo transferred and clinical pregnancy rate were assessed. RESULTS: Three hundred and forty-two consecutive IVF cycles were evaluated. One hundred and sixty-one cycles were from nulligravidas and 181 from women with a history of at least one previous clinical pregnancy. Forty-eight (29.8%) clinical pregnancies were observed in the nulligravida group and 56 (30.9%) in the gravida group. There were no differences between nulligravidas and gravidas in causes of infertility, length of ovarian stimulation, peak estradiol and progesterone levels, number of oocytes retrieved, fertilization rate and number of embryos transferred. Gravidas were significantly older (30.4 vs. 27.6 years, p < 0.001) and used more gonadotropin ampoules (36.1 vs. 31.8, p < 0.004) compared with the nulligravidas. CONCLUSIONS: Patient gravidity has no influence on the likelihood of achieving pregnancy in IVF-ET cycles. 相似文献
22.
Evan S. Siegelman Eric K. Outwater Emma E. Furth Raphael Rubin 《Journal of magnetic resonance imaging : JMRI》1995,5(6):730-732
Nodular regenerative hyperplasia (NRH), a rare condition that is commonly associated with noncirrhotic portal hypertension, is not well described in the MR literature. Three patients at two institutions were identified who had both abdominal MR imaging and pathologic evidence of NRH. All examinations were performed at 1.5 T and included axial T1- and T2-weighted spin-echo (SE) images. The MR studies were reviewed by two radiologists in consensus. Two patients had multiple liver lesions that had high signal components on T1-weighted images and were predominantly isointense with liver on the T2-weighted images. One patient had no focal lesions identified. NRH, when visualized on MR images, appears as multifocal masses with shortened Tl and T2 similar to liver. NRH should be considered in the differential diagnosis of hepatocellular tumors, especially in patients with a predisposing condition. 相似文献
23.
J. M. Porcher C. Lafuma R. El Nabout M. P. Jacob P. Sébastien P. A. Borm S. Honnons G. Auburtin 《International archives of occupational and environmental health》1993,65(Z1):S209-S213
This research is designed to evaluate a number of biological markers to estimate harmful exposure on coal miners from different mining regions in France and to relate the outcome to differences in prevalence of coal worker pneumoconiosis (CWP) between these regions. Eight epidemiological groups of active and ex-miners (smokers and non-smokers) have been selected in the French collieries (North, Lorraine and Provence) according to their occupational and pneumoconiotic status. The following biomarkers have been evaluated: cellularity of sputum, elementary analysis of particles in TEM/EDAX, plasma neutral metalloendo peptidase elastase type (NMEP), leucocyte elastase (HLE), fibronectin (FN) and elastin peptides. Pulmonary alveolitis, expressed by sputum cellularity, is different between active workers groups but not related to the general background of pneumoconiosis prevalence in the French collieries. In the plasma parameters, fibronectin, HLE and NMEP significantly increased in all groups of coal mine workers as compared to the control group, except for fibronectin parameter in Lorraine collierie. The degree of increase of these parameters allow us to discriminate the different groups and suggest that plasma FN, HLE and NMEP may be considered as biological markers of chronic inhalation of coal mine dust particles. The decrease of elastin peptides level in the Lorraine group alone suggests a specific alteration of elastin metabolism. These parameters were not related to the development of pneumoconiosis and its degree of severity. 相似文献
24.
T J Jacob 《Experimental eye research》1988,47(3):489-506
Microelectrode studies of fresh human and rabbit lens epithelia revealed stable membrane potentials [VR (human) = -36 mV; VR (rabbit) = -45 mV] and low input resistances [Ri (human) = 10 M omega; Ri (rabbit) = 20 M omega]. Coupling studies, using two voltage microelectrodes, demonstrated that the low input resistance of the fresh epithelial tissue was due to electrotonic coupling, which was found to be extremely labile and sensitive to perfusion of the apical (fibrefacing) surface of the epithelium. The intercellular coupling could be stabilized by raising the calcium concentration of the perfusate. Studies performed on confluent monolayers of cultured human lens epithelial (HLE) cells demonstrated a membrane potential (VR = -33 mV) and input resistance (Ri = 29 M omega) similar to their fresh counterparts. The intercellular coupling of these cells was found to be much more robust. Ultrastructural studies revealed that the apical junction of cultured HLE cells was less complex than that found in fresh tissue, the latter exhibiting multiple interdigitations and folds. The cultured monolayer was dissociated into single cells by a variety of methods and the membrane properties of individual cells were studied. Single cells were found to have a lower membrane potential (-20 to -25 mV) and an input resistance in the range 110-170 M omega, depending on the method of dissociation. Channel blocking and ion replacement studies revealed significant conductance pathways for potassium, sodium and chloride and a cell-attached patch clamp investigation revealed three distinct channel types. Of the two channels with inward currents at the resting potential, one, with a conductance of 25 pS, is identified as a non-selective cation channel, and the other, with a conductance of 14 pS and reversal potential of - 14 mV, is a possible candidate for a chloride channel but has yet to be characterized. A third channel with an outward current at the resting potential is identified as a potassium channel with a conductance of 49 pS. A link between epithelial uncoupling and certain types of cataract is proposed. 相似文献
25.
An outbreak of Salmonella dublin infection in England and Wales associated with a soft unpasteurized cows' milk cheese. 总被引:2,自引:0,他引:2
H Maguire J Cowden M Jacob B Rowe D Roberts J Bruce E Mitchell 《Epidemiology and infection》1992,109(3):389-396
An outbreak of Salmonella dublin infection occurred in England and Wales in October to December 1989. Forty-two people were affected, mainly adults, and most lived in south-east England. Microbiological and epidemiological investigations implicated an imported Irish soft unpasteurized cows' milk cheese as the vehicle of infection. A case-control study showed a statistically significant association between infection and consumption of the suspect cheese (p = 0.001). Salmonella dublin was subsequently isolated from cheeses obtained from the manufacturer's premises. Initial control measures included the withdrawal of the cheese from retail sale and a Food Hazard Warning to Environmental Health Departments, as well as a press release, from the Department of Health. Subsequently, a decision was taken by the manufacturer to pasteurize milk used in the production of cheese for the UK market and importation of the cheese resumed in June 1990. 相似文献
26.
Alcohol and Platelet Function 总被引:3,自引:0,他引:3
Epidemiological studies have shown that moderate consumption of alcoholic beverages is inversely related to the incidence of the complications of coronary artery disease. The protective effect of ethanol may be partially attributable to an inhibitory effect of ethanol on platelets. This article summarizes the experimental observations that ethanol inhibits platelet responses to specific physiological agonists. In alcoholics, various platelet defects have been observed, but these may be influenced by metabolic factors rather than the presence of ethanol alone. The acute effects of ethanol on platelet functions both in vivo and ex vivo will be reviewed. Evidence will be presented demonstrating that ethanol added acutely in vitro inhibits phospholipase A2 in stimulated platelets. The interaction of ethanol with other signal transduction pathways will also be discussed. 相似文献
27.
Nancy P. Caraway Gregg A. Staerkel Christina V. Fanning Datla G. Varma Raphael E. Pollock 《Diagnostic cytopathology》1994,11(3):255-261
The gross and microscopic appearances of aspirates from ten intramuscular myxomas are reported. The specimens were obtained from seven women and three men, ages 43 to 75, who had tumors involving the muscles of the thigh (7), upper arm (2), and forearm (1). Magnetic resonance (MR) imaging performed in six of the ten cases revealed well-defined, sharply demarcated tumors exhibiting low signal intensity relative to muscle on the T1-weighted images. The tumors were hyperintense to muscle on T2-weighted images. All aspirated tissues were clear, tenacious, and viscous. Smears contained few spindled and histiocytoid cells in an abundant mucoid background. Spindle cells demonstrated long cytoplasmic processes that in areas intertwined to form fibrillar tangles. Nuclei were oval to spindled with fine chromatin and inconspicuous nucleoli. Capillaries were sparse with simple (nonplexiform) branching. The differential diagnosis of myxoid lesions of the extremities includes benign entities such as myxoid schwannoma and neurofibroma, mesenchymal repair, and ganglion cyst, as well as malignant neoplasms such as myxoid liposarcoma, fibrosarcoma, malignant fibrous histiocytoma, and extraskeletal chondrosarcoma. The findings of this study revealed that, although the cytologic features were suggestive of intramuscular myxoma, a definitive diagnosis was often difficult, owing to scant cellularity and lack of distinctive cytologic features. The MR imaging findings may be utilized as an adjunct to the cytologic features to more confidently suggest a diagnosis of intramuscular myxoma. Diagn Cytopathol 1994;11:255–261. © 1994 Wiley-Liss, Inc. 相似文献
28.
Linda R White Lars Jacob Stovner Maurice B Vincent Ole Petter Løbben Yara D Fragoso Kristian S Bjerve Ottar Sjaastad 《Cephalalgia : an international journal of headache》1992,12(2):107-110
Our group has previously reported significant changes in the incorporation of precursors into glycerophospholipids, particularly phosphatidylserine, in polymorphonuclear cells obtained from the peripheral blood of cluster headache patients, when compared with controls. The potential of these results led to further work using both the previous methodology and a modified isolation technique to obtain polymorphonuclear cells in as pure a state as possible. Neither the new results obtained using the original technique, nor the results with high purity polymorphonuclear cells from controls and cluster headache patients, confirm the marked changes in precursor uptake into glycerophospholipids originally reported. 相似文献
29.
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