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991.
The first section of this article summarizes the salient clinicopathologic features of the more common types of primary gastrointestinal lymphomas, the recent explosion of information on the low grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT), and new findings on multiple lymphomatous polyposis and ulcerative jejunitis. The second section discusses the practical problems that may be encountered in the diagnosis of gastrointestinal lymphomas, including diagnosis of large cell malignancies, distinction between lymphoma and reactive lymphoid hyperplasia, classification of diffuse small B-cell lymphomas (including the potential pitfall of mistaking Burkitt's lymphoma for small B-cell lymphoma), recognition of large cell transformation in low-grade B-cell MALT lymphoma, assessment of gastric biopsies from MALT lymphoma patients after anti-Helicobacter therapy, and assessment of nodal or splenic involvement in low-grade MALT lymphoma.  相似文献   
992.
Peripheral neuropathy is common in the elderly and results in impairments in distal proprioception and strength that hinder balance and predispose them to falls. The loss of heel reflexes, decreased vibratory sense that improves proximally, impaired position sense at the great toe, and inability to maintain unipedal stance for 10 seconds in three attempts all suggest functionally significant peripheral neuropathy. Physicians can help their patients with peripheral neuropathy to prevent falls by teaching them and their families about peripheral nerve dysfunction and its effects on balance and by advising patients to substitute vision for the lost somatosensory function, correctly use a cane, wear proper shoes and orthotics, and perform balance and upper extremity strengthening exercises.  相似文献   
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994.
During the last trimester of pregnancy, 127 primiparous Irish mothers were interviewed to ascertain their history of alcohol and tobacco use. Confounding effects due to other drugs were not a factor in this sample. Mothers consumed an average of .21 ounces absolute alcohol (AA) per day, with 62% classified as moderate drinkers, 10.6% as heavy drinkers, and 26% as nondrinkers. Neurobehavioral status was measured using acoustic characteristics of the infant's cry, collected on the third day of life. Multiple regression analysis showed that more ounces AA per day was related to more dysphonation and higher first formant, while more cigarette smoking was related to higher pitch, higher second formant, and more variability in the second formant. Analysis of variance comparisons of these 3 alcohol groups demonstrated significant cry effects on infants of heavy drinking mothers.  相似文献   
995.
OBJECTIVE: Our purpose was to evaluate the effects of known stimulants of prostaglandin production on cultured myometrial cells from women in labor with and without intrauterine infection. STUDY DESIGN: Myometrial segments were obtained from 16 patients between 33 and 40 weeks' gestation who had been in labor for > or = 8 hours at cesarean delivery; 8 patients had clinical chorioamnionitis and 8 did not. Myometrial cells were isolated and grown in culture. Incubations were conducted with interleukin-1 beta, tumor necrosis factor-alpha, or epidermal growth factor. Prostaglandin E2, prostaglandin F2 alpha, and 6-keto-prostaglandin F1 alpha (the stable metabolite of prostacyclin) were measured by radioimmunoassay, and cellular protein was determined. RESULTS: Cultured human myometrial cells from patients with and without prior intrauterine infection produced prostaglandins in response to interleukin-1 beta, tumor necrosis factor-alpha, and epidermal growth factor at a significantly increased rate (p<0.05 vs controls at and above 10 ng/ml of interleukin-1 beta, tumor necrosis factor-alpha, and epidermal growth factor). The major prostaglandin produced in response to each stimulant was 6-keto-prostaglandin F1 alpha; however, this response was attenuated in cells from patients with intrauterine infection. CONCLUSIONS: Cultured human myometrial cells from patients with and without prior intrauterine infection respond to known stimulants of prostaglandin production. Prior intrauterine infection has no effect on baseline prostaglandin production, but the amount of prostacyclin produced as a response to cellular stimulants is decreased with prior intrauterine infection. This effect may have a role in regulating myometrial function in intrauterine infection.  相似文献   
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999.
  总被引:1,自引:0,他引:1  
ABSTRACT: Intrinsic fluorescent properties of muscle tissue were evaluated in order to characterize the different structural components of meat. The combinations of excitation and emission wavelengths showing the best ability to distinguish the 3 components were 290/332 nm for myofiber, 322/440 (or 322/405) nm for fat, and 380/440 nm for connective tissue. Sample orientation and the mincing of meat samples affected fluorescent amplitudes but not the overall shape of the spectra. These emission spectra of meat components were used to make multispectral images to determine whether the 3 components could be distinguished. The results show that auto fluorescence can be used for selective visualization of fat, fiber, and connective tissue on digitized images of meat.  相似文献   
1000.
Pleomorphic adenoma can show diverse lines of differentiation in the epithelial and myoepithelial elements, such as cartilage, bone, and fat. Myoid differentiation, however, has not been documented. We report an unusual case of nasal pleomorphic adenoma which shows focal skeletal muscle differentiation. The tumor was discovered only after successful radiation therapy for an undifferentiated carcinoma of the nasopharynx. Apart from being of morphological interest, the presence of cells with skeletal muscle differentiation also raises the practical issue of possible confusion with rhabdomyosarcoma in a biopsy. The distinguishing features are lack of cytological atypia and presence of a neoplastic glandular element.  相似文献   
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