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Peripheral administrations of TFMPP (0.2- 1 mg/kg) or MCPP (1 mg/kg) facilitated lordosis behavior in female rats treated with estradiol benzoate, and had no effects in females primed with estradiol benzoate and progesterone. In contrast, TFMPP (1 mg/kg) and MCPP (1 mg/kg) inhibited copulatory behavior in male rats. It is concluded that there are sex differences in the effects of TFMPP and MCPP on copulatory behavior in the rat. Moreover, it is suggested that the effects of these drugs on copulatory behavior may be mediated by activation of 5-HT1B and/or 5-HT1C receptors, or by blockade of activity at 5-HT3 receptors. 相似文献
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E B Mendelson 《Radiologic clinics of North America》1992,30(1):107-138
With widespread use of mammography for breast cancer screening, the number of surgical procedures has also increased. Overlapping with radiographic signs of malignancy, including masses, areas of asymmetric density and architectural distortion, microcalcifications, and skin thickening, postsurgical changes may make mammographic evaluation difficult. After tumor excision and irradiation where breast alterations are more profound and prolonged, the task of distinguishing recurrent tumor from scarring or fat necrosis is even more challenging. Mammograms after breast conservation therapy for carcinoma or after cosmetic surgery require correlation with physical findings and the surgical procedures that were performed. Responses of tissue to lumpectomy and radiation, such as breast edema and skin thickening, are most pronounced 6 to 12 months after treatment, gradually resolving within 1 to 3 years. Carefully tailored mammographic studies will promote the dual goal of early detection of local tumor recurrence and avoidance of misinterpreting postoperative and irradiation changes as malignancy. Sequential examinations should begin with a postoperative preradiation mammogram for residual carcinoma, particularly when microcalcifications have been present, followed by the baseline postradiation examination at 6 months with the next study 6 months later (1 year after initial treatment). Mammograms of the treated breast may be performed at intervals of 6 months until radiographic stability has been recognized. Annual studies thereafter are suggested. The contralateral, unaffected breast should be evaluated mammographically according to screening guidelines or clinical concerns. Mammograms performed after cosmetic and reconstructive procedures should be correlated with the surgical techniques and clinical history. Modified views for silicone implants can maximize visualization of breast parenchyma. Ultrasonography is a useful complement to mammography in demonstrating the origin of a palpable mass either within the implant or the breast parenchyma. In reduction mammoplasty, distorted architecture, parenchymal bands, tissue redistribution, and fat necrosis should be recognized. After mastectomy, myocutaneous reconstruction may be performed. Masses that develop within flap reconstructions most frequently represent fat necrosis, which, when calcifying oil cysts are seen, may have a characteristic radiographic appearance. 相似文献
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Sex differences in plasma cocaine levels and subjective effects after acute cocaine administration in human volunteers 总被引:3,自引:3,他引:0
S. E. Lukas M. Sholar L. H. Lundahl X. Lamas E. Kouri J. D. Wines L. Kragie J. H. Mendelson 《Psychopharmacology》1996,125(4):346-354
Gender differences after acute cocaine administration have received little attention in spite of the fact that males and females respond differently to many drugs. Seven male and seven female occasional cocaine users received both an intranasal dose of cocaine hydrochloride (0.9 mg/kg) and placebo powder in a randomized order and reported subjective effects via an instrumental joystick device and various questionnaires. Blood samples were withdrawn at 5-min intervals to assess pharmacokinetic differences. Male subjects achieved the highest peak plasma cocaine levels (144.4 ± 17.5 ng/ml), detected cocaine effects significantly faster than females and also experienced a greater number of episodes of intense good and bad effects. Women studied during the follicular phase of their menstrual cycle had peak plasma cocaine levels of 73.2 ± 9.9 ng/ml, which was significantly higher than when they were studied during their luteal phase (54.7 ± 8.7 ng/ml), but there were no differences in their subjective reports of cocaine effects. In spite of the different cocaine blood levels and subjective effects, peak heart rate increases did not differ between males and females suggesting that women may be more sensitive than males to the cardiovascular effects of cocaine. These data suggest that there are significant gender and menstrual cycle differences in the response to acute intranasal cocaine administration and these differences may have implications for the differential abuse of this drug.This paper is dedicated to Xavier Lamas, MD, PhD, who lost his life while ascending Mt. Everest, August 1995 相似文献
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D S Mendelson B D Berson C L Janus E S Gendal D J Krellenstein 《Journal of computer assisted tomography》1988,12(5):881-884
A patient undergoing treatment for abdominal lymphoma presented with a superior vena cava (SVC) syndrome. The presence of a wide mediastinum and "nodular" mediastinal densities on CT presented a diagnostic problem, necessitating thoracotomy. The thoracotomy was negative for tumor or infection. We believe that the presence of an indwelling catheter and mediastinal lipomatosis resulted in the SVC syndrome. The "nodular" densities represented an unusual set of mediastinal collaterals that must be distinguished from adenopathy. 相似文献
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Sleep apnea syndrome in chronic renal disease 总被引:10,自引:0,他引:10
PURPOSE: We performed this study in order to expand on an earlier report indicating a high prevalence of the sleep apnea syndrome in male patients with end-stage renal disease treated with hemodialysis and to determine whether patients with chronic renal insufficiency (prior to the initiation of therapy for end-stage renal disease) and female patients with end-stage renal disease treated with hemodialysis were affected. PATIENTS AND METHODS: Polysomnography was performed in 26 male and female patients with chronic renal insufficiency and end-stage renal disease treated with hemodialysis who were not receiving testosterone. They included 22 whose histories were suggestive of sleep apnea ("symptomatic") and four whose histories were not ("asymptomatic"). RESULTS: Sixteen of the symptomatic (73 percent) and none of the asymptomatic patients were found to have clinically significant sleep apnea syndrome (p less than 0.02). Both female patients and patients with chronic renal insufficiency had sleep apnea. In nine of these 16 cases, the disorder was primarily of the obstructive type. CONCLUSION: These preliminary data raise the possibility of an association of chronic renal disease and the sleep apnea syndrome, and suggest that some of the daytime sleepiness and disturbed nocturnal sleep in such patients may be related to sleep apnea. They also indicate that questioning patients with chronic renal disease and symptoms suggestive of a sleep disorder is useful in determining who are at high risk for the sleep apnea syndrome. Further study is required to establish a causal relationship between chronic renal disease and the sleep apnea syndrome, and to determine the prevalence of the latter in patients with end-stage renal disease. 相似文献
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Studies of proteins that inhibit tissue factor activity have generally been conducted using either an extracted tissue homogenate ("thromboplastin") or tissue factor protein reconstituted into phospholipid vesicles rather than with tissue factor expressed in cell membranes (its physiological environment). In the present study, a human fibroblast cell strain was used to evaluate the effects of lipoprotein associated coagulation inhibitor (LACI), placental anticoagulant protein (PAP), and apolipoprotein A-II (apo A-II) on human tissue factor in cell membranes. LACI was tested from 7.8 to 500 pmol/L on fibroblasts cultured at cell densities ranging from 3,500 to 9,925 cells/well, and caused a progressive inhibition of tissue factor activity. PAP was tested from 3.9 nmol/L to 1 mumol/L at cell densities ranging from 4,500 to 15,400 cells/well and caused up to 83% inhibition of tissue factor activity. Inhibition by these proteins appeared to be influenced by cell density as well as whether the cells were intact or disrupted. Apo A-II, up to 1 mumol/L, did not inhibit the tissue factor activity of intact or disrupted fibroblasts at any cell density examined even though it did inhibit the activity of tissue factor in phospholipid vesicles. Of these inhibitors of tissue factor-dependent activation of factor X, LACI was the most effective in suppressing the generation of factor Xa activity. The effects obtained with apo A-II are clearly dependent on the nature of the tissue factor preparation with which it is tested. The disparity between the inhibitory effect of apo A-II on the activity of tissue factor reconstituted into lipid vesicles and the absence of effect on the activity of tissue factor remaining in cell membranes serves to reemphasize the necessity of reexamining results obtained with model systems using as nearly physiological reagents as possible. 相似文献
10.
Ability of National Committee for Clinical Laboratory Standards-recommended quality control strains from the American Type Culture Collection to detect errors in disk diffusion susceptibility tests.
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A Yechouron A Dascal J Stevenson J Mendelson 《Journal of clinical microbiology》1991,29(12):2758-2762
The National Committee for Clinical Laboratory Standards (NCCLS) recommends, as a quality control for the disk diffusion susceptibility test, the use of three strains from the American Type Culture Collection: Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922. This study assesses the capacity of these strains to detect errors in the overall method. ATCC strains were tested by comparing testing by the standard NCCLS-recommended procedure (ST) with testing under the following conditions: incubation at 25 degrees C, Mueller-Hinton agar depths of 2 mm (AD2) and 8 mm (AD8), agar pHs of 6.5 and 8, inocula with McFarland standards of 0.25 (0.25M) and 4.0 McFarland (4.0M), direct inoculation without preincubation of inoculum (DI), and a 2-h delay between inoculation and disk application (2HR). The frequency of zone measurements outside the NCCLS-recommended control zone limits were as follows: ST, 0%; AD2, 18%; AD8, 9.6%; pH 6.5, 7.9%; pH 8, 5.3%; 0.25M, 3.5%; 4.0M, 24%; DI, 3.4%; 2HR, 1.8%; 25 degrees C (only E. coli and P. aeruginosa were evaluable), 28%. These results suggest that the quality control strains are only partially effective in detecting single extreme laboratory errors and that careful laboratory supervision is necessary even in the setting of properly monitored quality control strains. 相似文献