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21.
The monoclonal antibody MAb 1-7-1, which specifically binds to cytochromes P-450IA1 and P-450IA2 in 3-methylcholanthrene-induced rat liver microsomes, was used to identify a cytochrome P-450IA1 homologue in human lung microsomes. Although MAb 1-7-1 had similar affinity constants for human and rat microsomes, the amount bound to human lung microsomes was severalfold lower than that bound to microsomes from untreated rat or rabbit lung and much lower than the amount bound to 3-methylcholanthrene-induced rat lung or liver microsomes. The amount bound to untreated baboon lung microsomes was similar to that bound to human lung microsomes. Three cytochrome P-450IA1-catalyzed activities, 7-ethoxyresorufin O-deethylase, 7-ethoxycoumarin, O-deethylase, and aryl hydrocarbon hydroxylase, were measurable in human lung microsomes, but the cytochrome P-450IA2-dependent activity acetanilide 4-hydroxylase was not. MAb 1-7-1 inhibited, and its binding correlated strongly with, 7-ethoxyresorufin O-deethylase activity (r = 0.92, p less than 0.01) in human lung microsomes. 7-Ethoxyresorufin O-deethylase activities in human lung were similar to those measured in untreated baboon lung but considerably lower than those present in untreated rabbit lung, untreated or 3-methylcholanthrene-induced rat lung and liver, or human liver. We conclude that MAb 1-7-1 recognizes a cytochrome P-450IA1 homologue in human lung and that no cytochrome P-450IA2 homologue is detected. Cytochrome P-450IA1 is expressed in human lung at relatively low levels, similar to those observed in untreated primate (baboon) lung. The majority of the 19 human lung samples examined do not exhibit a permanent polycyclic aromatic hydrocarbon-induced state with respect to this isozyme.  相似文献   
22.
This paper reports the results of a survey in which pregnant women in London and Edinburgh were asked about their knowledge and understanding of the recent recommendations of expert committees (James, 1983; DHSS, 1984). In general, Londoners had a better understanding, although in both regions manual groups were less knowledgeable, with the Edinburgh manual group the least well informed.  相似文献   
23.
The introduction of the Malone procedure has improved the outlook for children with severe faecal incontinence. Phosphate and saline enemas are administered through the exteriorized appendix in antegrade fashion to achieve evacuation and ensure cleanliness. The appendix functions as a non-refluxing catheterizable channel: If it is not available for use, a tubularized caecal flap is a safe alternative. We have constructed Malone stomas using the appendix in 20 patients and another seven patients have undergone the caecal flap modification. The mean age was 8.6 years. Eleven of the patients were boys and 16 (59%) were girls. Six children required dilatation or revision of their stomas for stenosis. One developed small bowel obstruction and another has stopped using the stoma. The results of the continence enemas were considered to be very good by the vast majority of patients and their carers. Our recent experience suggests that bisacodyl may be a valuable adjunct to the antegrade enemas of phosphate and saline. We believe that this procedure may be extended with benefit to adults with serious faecal incontinence in whom standard measures have failed.  相似文献   
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25.
Treatment of AtT-20 cell cultures with increasing concentrations of rat/human corticotropin-releasing factor (r/hCRF) for 24 h resulted in a dose-dependent 2-3 fold increase in specific 125I-labelled recombinant human IL-1 alpha (125I-IL-1 alpha) binding that was paralleled by a 70-80% decrease in 125I-Tyro-ovine CRF binding. Saturation analysis of 125I-IL-1 alpha binding in control and CRF-treated cultures indicated that CRF produced an increase in the density (Bmax) of IL-1 receptors without altering their affinity (KD). The CRF-induced upregulation of IL-1 receptors appears to be mediated through specific membrane receptors for CRF since the CRF receptor antagonist, alpha-helical oCRF (9-41), blocked the CRF-induced upregulation of IL-1 receptors without producing any effect on 125I-IL-1 alpha binding by itself. In summary, these data demonstrate complex interactions between CRF and IL-1 at the pituitary level and identify potential novel mechanisms for cytokines to alter neuroendocrine function.  相似文献   
26.
27.
In today's busy and demanding world, we no longer have the luxury of taking weeks to recover from a surgical procedure and are more frequently seeking quicker alternatives. The use of dermal fillers meets this need but in no way replaces a surgical intervention. Previously, bovine collagen was the only approved dermal filler. However, today there are several options available including a human collagen, a variety of hyaluronic acids, and a permanent injectable product. Each of the products has different uses, indications, and adverse reactions. The experienced injector now has a wider selection of products from which to choose to ensure that the patient receives what is best suited for his or her particular situation. These new products are becoming increasingly popular, due to acceptability and affordability, but are not without potential complications and adverse reactions. This article discusses the use of Cosmoderm/Cosmoplast, Hylaform, Restylane/Perlane, and Artecoll dermal fillers.  相似文献   
28.
Intra-arterial chemotherapy for the treatment of localized malignant neoplasms in the head and neck is an appealing approach for several reasons. Perhaps the most important is the possibility of obtaining a regional advantage such that an increased drug concentration is delivered systemically. The patient may, therefore, be spared systemic toxicity. We report our accumulated experience using a totally implantable infusion pump in 37 patients. A total of 42 pumps were implanted: 28 single-catheter pumps and 14 dual-catheter pumps. Radionuclide imaging demonstrated total perfusion of the tumor in all patients. A combination of cisplatin (50 to 100 mg/m2) and floxuridine (0.01 to 0.045 mg/kg/d) was used to treat 26 patients. For these heavily pretreated patients, we observed a 43% complete and partial response rate in the subgroup of patients with squamous cell carcinoma. These results are comparable with those reported for these drugs administered systemically and for other drug combinations tested in the treatment of recurrence disease.  相似文献   
29.
During the first 24 months of the Oregon Liver Transplantation Program, which began in October 1988, 94 patients were formally evaluated and 47 adults underwent 54 liver transplantations. Thirty-four percent of patients were veterans. The recipient operation lasted a mean of 7.4 hours (range: 4 to 16 hours). Veno-venous bypass was used routinely at first but selectively later (7 of the last 26 cases), resulting in reduced operating time. Hepatic artery reconstruction was end-to-end anastomosis in 52 cases and iliac conduit in 2. No arterial thrombosis occurred. Biliary reconstruction was choledochocholedochostomy in 83% and choledochojejunostomy in 17%. Biliary complications occurred in 28%. Operative mortality was 2%, and 1-year actual survival was 80%. Patients with hepatitis B fared worse, with four of six dying at a mean of 7.6 months. Overall, the median hospital stay was 30 days. Patients surviving more than 3 months had a mean Karnofsky score of 82%. No significant difference in outcome was noted in patients receiving prophylactic OKT3 monoclonal antibody (used in 45%) versus conventional immunosuppressive therapy. Overall, allograft rejection occurred in 55% of patients. Retransplantation was required in seven patients, three for primary graft nonfunction, two for uncontrolled rejection during induction therapy with OKT3, and two for graft failure secondary to recurrent hepatitis B.  相似文献   
30.
Conjugates of poly-N-methylglycine (polysarcosine) and grass pollen extracts, previously found to be capable of suppressing immature IgE antibody responses in mice, were shown to be highly effective at inhibiting the capacity of immune splenocytes to produce a secondary response in sub-lethally irradiated recipient animals. Anamnestic IgE responses in mice primed without adjuvant were also suppressed, but the effects were modest and of short duration. The predictive value of murine models for selecting clinically appropriate specific IgE suppressive agents and treatment schedules that might be successfully employed for clinical use are discussed.  相似文献   
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