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101.
BACKGROUND AND OBJECTIVES: To note the effect on filtration function of using polyglactin sutures for scleral flap suturing in trabeculectomy. PATIENTS AND METHODS: Polyglactin sutures were compared with nylon sutures to secure the scleral flap of trabeculectomy in 30 consecutive eyes. Parameters studied were intraocular pressure, central anterior chamber depth, and bleb score in this randomized prospective study. RESULTS: Observations regarding intraocular pressure, central anterior chamber depth and bleb score in the early postoperative period were comparable in the 2 groups. The results at 12 months follow-up reveal a lower mean IOP (P < 0.05) and a higher mean bleb score (P < 0.05) in the group with polyglactin sutures. Success rate (defined as IOP < 21 mm Hg) at 12 months was 100% with use of polyglactin sutures compared to 80% with nylon sutures. CONCLUSIONS: Polyglactin sutures can be used as an alternative to nylon sutures for scleral flap suturing in trabeculectomy, with the possible additional benefit of better long-term filtration function.  相似文献   
102.
Important inroads are being made into understanding the pathophysiology of diarrhea. Clear understanding of key mechanisms should suggest new approaches to combat disease. Exciting developments are occurring in terms of super-ORS solutions, particularly with the promise of short chained glucose polymers and glutamine. Perhaps the most important development is the prospect of a good rotavirus vaccine being available before the end of the decade. Chronic diarrhea seems to be on the increase globally, probably because of the success of ORS. The mechanisms that lead to mucosal injury are elusive, and therapy still largely supportive and empiric. Celiac disease continues to be a puzzle, because of the uncomfortable feeling that a majority of cases may be missed because of atypical presentations. The successful use of long term parenteral nutrition has allowed survival and better charaterization of cases that otherwise would have perished as ‘lethal protracted diarrhea’. Microvillus inclusion disease may be the commonest congenital secretory diarrhea. The role of the recently reported high prevalence of glucoamlase deficiency may be important. Lastly, attention to micronutrients, particularly low vitamin A and probably zinc may prove to be important in prevention and amelioration of diarrhea and growth failure.  相似文献   
103.
104.
Over a follow-up period of 6 years, 4 out of 31 live related renal allograft recipients (12.9%) developed azathioprine induced bone marrow suppression. Presentation in 3 patients was with fever and 2 patients also had associated graft dysfunction. All patients had leucopenia, 2 patients in addition had anaemia and one patient had pancytopenia. Bone marrow suppression developed 9.6 months (3.5-16.0 months) following transplantation and recovery followed over a period of 30 (18-49 days) days after withdrawal of the drug. One patient succumbed during the phase of bicytopenia.KEY WORDS: Azathioprine, Bone marrow suppression, Kidney transplantation  相似文献   
105.
Of the 253 neonates admitted to a neonate intensive care unit during the period Jan 91 to Sep 93, 43 neonates died. Autopsy was done in 23 of these (53%). The mean duration of stay of the neonates in the intensive care unit prior to death was 5.6 days (range 2 hours to 10 days). Antemortem diagnoses included asphyxia neonatorum (4), meconium aspiration syndrome (2), septicemia (5), prematurity (3), birth trauma (2), congenital anomalies (2), hypoxic ischemic encephalopathy (1), and non-specific diagnosis (4). There were 6 major autopsy findings that, if known prior to death, would have altered clinical management and might have resulted in cure or prolonged survival. There were 8 additional major findings that, if known prior to death, would not have altered management There were 14 minor findings related to major diagnoses but unrelated to the primary cause of death.KEY WORDS: Autopsy, Cause of death, Perinatal mortality  相似文献   
106.
Altered metabolism of all-trans-retinoic acid in liposome-encapsulated form   总被引:3,自引:0,他引:3  
Treatment with all-trans-retinoic acid (ATRA) induces complete remission in many acute promyelocytic leukemia patients. However, plasma drug levels progressively decrease following prolonged treatment with oral ATRA. This decrease is due, at least in part, to the induced cytochrome P-450-dependent metabolism of ATRA. To investigate if incorporation of ATRA in liposomes could alter its metabolism, we compared the cellular metabolism of liposomal-ATRA (L-ATRA) with free drug. Microsomes isolated from the rat liver metabolized L-ATRA to a significantly lower extent than they did free-ATRA. Similarly, in F9 cells, L-ATRA was metabolized at a slower rate than the free drug. These results suggest that L-ATRA may have important clinical implications in terms of slowing down the rate of ATRA metabolism and producing long-term remission in APL patients.  相似文献   
107.
Summary The pyridylglutarimide 3-ethyl-3-(4-pyridyl)-piperidine-2,6-dione (PyG) is a novel inhibitor of aromatase that was shown to cause effective suppression of plasma oestradiol levels in postmenopausal patients. In four patients receiving oral doses of PyG (500 mg) twice daily for 3–4 days, oestradiol levels fell to 31.1%±6.3% of baseline values within 48 h and remained suppressed during treatment. Of a further six patients who received oral PyG (1 g) as a single dose, five had quantifiable oestradiol levels. Oestradiol suppression was sustained for 36 h and recovery correlated with a fall of PyG concentrations below a threshold value of ca. 2 g/ml. The pharmacokinetics of PyG were non-linear and, when fitted to the integrated Michaelis-Menten equation, yielded good parameter estimates forC o (21.7±1.82 g/ml),K m (2.66±0.68 g/ml) and Vmax (0.86±0.06 g ml–1 h–1). On subsequent repeated dosing with PyG, both theK m (4.31±0.48 g/ml) and the Vmax (1.83±0.13 g ml–1 h–1) values increased and recovery from oestradiol suppression was more rapid, indicating that PyG induces its own metabolism.Abbreviations PyG 3-ethyl-3-(4-pyridyl)piperidine-2,6-dione - AG aminoglutethimide - CSCC cholesterol side-chain cleavage - HPLC high-performance liquid chromatography - AUC area under the concentration versus time curve This study was supported in part by grants to the Institute of Cancer Research (Royal Cancer Hospital) from the Cancer Research Campaign and Medical Research Council  相似文献   
108.
Summary This study examines the paracrine influence by human breast carcinoma cells (UISO-BCA-1) on nonmalignant breast tissuein vitro. The 17-OH-SDH-mediated reductive pathway (estroneestradiol) was significantly increased in nonmalignant breast tissue coincubated with human breast carcinoma cells, compared to control tissues incubated in the media alone. No influence on the enzyme activity was noticed in coincubated breast cancer cells. Preincubation of breast cancer cells with estradiol (10–8 M) significantly decreased the enzyme activity in coincubated nonmalignant breast tissue, which was restored to control levels by addition of R5020 (10–8 M), tamoxifen (10–6 M), or a combination of both. In nonmalignant tissues incubated in the presence of growth factor TGF, enzyme activity was reduced to between 46% and 76%. No other growth factors (IGF I, IGF II, PDGF) influenced enzyme activity. In nonmalignant tissues incubated with malignant tumor cytosol, enzyme activity was increased in 16% cases, inhibited in 21%, and not significantly changed in 63%.The data from the present study suggest that factors produced by breast carcinoma cells may influence interconversion of estradiol in nonmalignant tissue. In patients, factors produced by malignant tumor mass may have paracrine influence on surrounding nonmalignant breast tissue and, thereby, may influence the estrogen availability to tumor mass.  相似文献   
109.
This paper provides the first evidence that the Lathyrus sativus neurotoxin, l-3-oxalylamino-2-aminopropionic Acid (OAP), is toxic when administered intraperitoneally to a primate with a mature bloodbrain barrier. Drowsiness, vomiting, muscle tremors, twitching, convulsions, and death occurred in young male squirrel monkeys (Saimiri sciureus) following injection of 4.26 and 11.4 μmol (0.750 and 2.00 mg) OAP/g body wt. Electroencephalographic changes characteristic of each stage of intoxication were observed. Unchanged OAP was recovered from brain of intoxicated animals. These observations support a possible role for OAP in the etiology of human neurolathyrism, a paralytic disease prevalent among adults in Central India who have consumed large quantities of L. sativus seeds for several months.  相似文献   
110.
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