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31.
A case of esophageal perforation occurring in a 75-year-old man is presented. The clinical presentation was benign and the diagnosis of esophageal perforation was made incidental to an upper gastrointestinal barium examination. Conservative management consisting of nasogastric suctioning, antibiotics and antacids was effective in minimizing the clinical course. This represents a rare instance of a successful nonsurgical approach to esophageal perforation.  相似文献   
32.
1. Chronically cannulated sheep foetuses and suckling lambs were injected with 14C-labelled glucose, fructose or lactate, and sequential blood samples taken under conditions of minimal stress and without anaesthesia. 2. Gluconeogenesis from lactate was not detectable in foetal sheep, but the pathway was active in suckling lambs. 3. Fructose utilization rates were low in foetal sheep, with no measurable conversion into glucose or lactate. 4. The high rates of irreversible loss of both glucose and lactate in the foetus were decreased in suckling lambs. Radioactivity from labelled glucose entered both the lactate and fructose pools in foetal sheep, and entered the lactate pool in suckling lambs. 5. A model is proposed in which carbon flow between glucose, fructose and lactate has been quantified in foetal sheep.  相似文献   
33.
Three cheetahs (Acinonyx jubatus) had a clinical history of chronic spiral bacteria-associated gastritis and three cheetahs had no clinical history of gastritis. Gastric biopsies were obtained from all six cheetahs prior to treatment for gastritis and 3 wk and 1 yr posttreatment. The cheetahs were treated with tetracycline hydrochloride 500 mg p.o. q.i.d., metronidazole 250 mg p.o. q.i.d., and bismuth subsalicylate 300 mg p.o. q.i.d. Each drug was administered concurrently for 7 days. Following this treatment, each cheetah was maintained on 300 mg bismuth subsalicylate p.o. s.i.d. for 1 yr. The three cheetahs with a history of gastritis were culture positive for Helicobacter acinonyx and remained positive during the entire study. The three cheetahs with no clinical history of gastritis were culture negative for H. acinonyx, but gastric biopsies revealed Gastrospirillum-like bacteria (tentatively named Helicobacter heilmannii) pretreatment. Gastric biopsies were negative for H. heilmannii on subsequent examinations. Although the treatment did not eradicate H. acinonyx, it did provide symptomatic relief from the vomiting, anorexia, and weight loss associated with clinical gastritis. The use of endoscopically guided gastric mucosal biopsies for urease testing and histopathologic examination of Warthin-Starry-stained sections is a sensitive and specific method of diagnosing spiral bacteria-associated gastritis. Treatment of spiral bacteria-associated gastritis in cheetahs should include the rational use of antibiotics (tetracycline or amoxicillin and metronidazole), bismuth compounds, and omeprazole and evaluation of husbandry methods to reduce stress.  相似文献   
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35.
OBJECTIVE: To determine the diagnostic value of indirect immunofluorescence on sodium chloride-split skin (SSS) in differentiating the pemphigoid group of subepidermal autoimmune bullous dermatoses, including bullous pemphigoid (BP), cicatricial pemphigoid, and pemphigoid gestationis, from epidermolysis bullosa acquisita (EBA). DESIGN: Serum samples were tested using immunofluorescence on SSS and immunoblot assay on epidermal and dermal extracts, a recombinant protein corresponding to the C-terminal end of the 230-kd BP antigen, and purified laminin-5. SETTING: An immunodermatology laboratory. PATIENTS: One hundred forty-two serum samples from patients with BP (n = 98), cicatricial pemphigoid (n = 23), pemphigoid gestationis (n = 10), EBA (n = 10), and anti-type IV collagen (n = 1). MAIN OUTCOME MEASURES: Binding sites of serum to the epidermal and/or dermal sides of SSS were correlated with their antigenic specificities. RESULTS: Epidermal staining on SSS was highly specific for pemphigoid. Alternatively, a poor correlation was found for the dermal-reacting serum samples and the diagnosis of EBA; of the 19 serum samples with dermal staining on SSS, only 10 reacted with the EBA antigen. The remaining serum samples were from patients with cicatricial pemphigoid having antibodies to the alpha 3 or beta 3 chains of laminin-5 (n = 5) or patients with BP having antibodies to the 180-kd BP antigen (n = 2). One sample recognized exclusively a 185-kd dermal antigen corresponding to type IV collagen. One more BP serum sample with dermal staining did not recognize any dermal or epidermal antigen. CONCLUSION: In case of immunofluorescent dermal staining, the precise diagnosis should be confirmed by identification of the involved antigen, since it may reveal antibodies to laminin-5 or type XVII or IV collagen, in addition to the EBA antigen.  相似文献   
36.
This study investigated factors that influence the placental transfer of sufentanil using the dual-perfused, single-cotyledon human placental model. Placentas were collected from healthy women. Experiments were designed to elucidate the effects of maternal protein binding, changing maternal sufentanil concentration (1, 10, 20, and 100 ng/mL) and decreasing fetal pH (fetal acidemia 7.2, 7.0, 6.8) on the placental transfer of sufentanil. Sufentanil crossed the placenta rapidly at a rate two-thirds that of the transfer marker, antipyrine. Sufentanil transfer increased linearly with the maternal concentration (r = 0.999). Sufentanil/antipyrine maternal to fetal (M-->F) transfer ratios were significantly reduced (0.66 +/- 0.05 vs 0.40 +/- 0.04, P < 0.05) when fresh frozen plasma was added to the maternal circuit to enhance protein binding. Fetal pH and sufentanil transfer were related because sufentanil M-->F clearance increased significantly as the fetal pH decreased (r = 0.973, P < 0.05). Sufentanil appears to cross the placenta by passive diffusion but is modulated by the degree of maternal protein binding. Sufentanil M-->F transfer is enhanced by fetal acidemia.  相似文献   
37.
We investigated whether cigarette smoking, measured by follicular fluid concentrations of cotinine (a major metabolite of nicotine), affects the maturity of oocytes from women undergoing in-vitro fertilization (IVF) and embryo transfer. In 234 women, follicular fluid samples were assessed for cotinine and their 2020 oocytes were assessed for maturity stage. Data on individual proportions of oocytes which were mature (OM) and were fertilized (OF) were analysed by regression in relation to age and follicular fluid cotinine. OF gave an independent assessment of oocyte maturity. Both age and follicular fluid cotinine entered the OM and OF regressions and were significant. The age-adjusted regression coefficients for log cotinine were positive; greater cotinine concentrations usually accompanied greater OM and OF. The cotinine effect on OM was positive in younger women, but it became negative (decreased OM with increasing cotinine concentrations) in older women (> or = 40 years). We further found in older women an average reduction of approximately 50% in the number of mature oocytes; this reduced number was lower than the number of embryos usually transferred. Smoking can reduce the number of mature oocytes even further, therefore risking a negative IVF-embryo transfer outcome. This may be the reason why the negative effects of smoking become clinically detectable in older women.  相似文献   
38.
On the basis that melanomas are of neural crest origin and might contain somatostatin receptors, the authors utilized 111In Pentetreotide (OctreoScan) to image 16 melanoma patients with known sites of disease. Twelve of 16 patients were positive with 38 percent imaging all sites. No lesion less than 1.5 cm imaged nor did one ocular and one amelanotic melanoma. Of the five described somatostatin receptors, OctreoScan binds only 2 and 5 suggesting that not all melanomas contain those receptors. It is concluded that melanomas contain somatostatin receptors and that this property might be used for imaging, tumor suppression with Octreotide, and/or as a target for Octreotide labelled with therapeutic agents such as immune complexes, chemotherapeutic agents or high energy radioisotopes.  相似文献   
39.
Promising results from clinical trials with unconjugated antibodies stimulated renewed interest in immune effector mechanisms of monoclonal antibodies (MoAbs). We investigated the potential of IgA as antibody isotype for cell- or complement-mediated tumor cell lysis and assessed the potential of its myeloid Fc receptor, FcalphaRI (CD89), as trigger molecule for bispecific antibody (BsAb)-mediated immunotherapy. Comparing hapten-directed antibodies of human IgA2 with IgG1 or IgG3 isotypes, we found all three to mediate effective killing of sensitized tumor target cells in whole blood assays. Analysis of effector mechanisms showed IgG-mediated lysis to be predominantly complement-dependent, whereas IgA-dependent killing was primarily effector cell-mediated. A comparison of effector cell populations in antibody-dependent cell-mediated cytotoxicity (ADCC) showed neutrophils to be most important for IgA-dependent tumor cell killing, involving FcalphaRI as shown with Fc receptor blocking antibodies. Reverse ADCC experiments against target cells sensitized with Fc receptor antibodies, or assays with FcalphaRI-directed bispecific antibodies confirmed FcalphaRI as effective trigger molecule in polymorphonuclear neutrophil (PMN)-mediated lysis. During granulocyte colony-stimulating factor (G-CSF ) therapy, (FcalphaRI x HER-2/neu) bispecific antibodies induced enhanced killing of HER-2/neu positive SK-BR-3 breast cancer cells in whole blood assays. This enhanced cytotoxicity was paralleled by increased PMN counts, which lead to higher effector to target cell ratios in G-CSF-primed blood. Furthermore, bispecific antibodies, directed to FcalphaRI and Candida albicans, enhanced neutrophils' phagocytosis of fungi. In summary, these results identify IgA as an effective antibody isotype for immunotherapy, working primarily via FcalphaRI on neutrophils. They suggest FcalphaRI-directed bispecific antibodies and G-CSF to be an attractive combination for malignant or infectious diseases.  相似文献   
40.
We examined whether either psychotic features (e.g., delusions and hallucinations) or EEG abnormalities are associated with more rapid progression of Alzheimer's disease (AD). AD patients with psychosis have exhibited more EEG abnormalities than those without psychosis, and both abnormal EEG and psychosis have been noted to be predictors of functional and cognitive decline in AD. Ninety-five probable AD patients participating in a longitudinal study of dementia had an EEG and a semistructured psychiatric interview at baseline. Using EEG spectral analysis, we classified records as normal/abnormal based on the parasagittal mean frequency. Patients with abnormal EEGs were more functionally (e.g., Blessed Rating Scale for activities of daily living) and cognitively (e.g., Mini-Mental State) impaired than patients with normal EEG. AD patients with psychosis were only more functionally impaired than patients without psychosis. A two-factor analysis showed no interaction between abnormal EEG and psychosis. In addition, using a Cox proportional hazard model adjusted for age and education, the presence of an abnormal EEG or psychotic symptom at study entry was associated with higher risk of reaching severe cognitive and functional impairment during follow-up. Neither abnormal EEG nor the presence of psychosis predicted death. These results indicate that both abnormal EEG and psychosis are independent predictors of disease progression but not of physical survival.  相似文献   
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