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991.
The effect of storage on the physical stability of solid dispersions of triamterene or temazepam in polyethylene glycols was studied using differential scanning calorimetry (DSC), particle-size analysis and dissolution methods. The enthalpies of fusion of the carriers, without included drug and previously fused and crystallized, increased on storage. Analysis of similarly treated solid dispersions, containing either 10% temazepam or 10% triamterene, showed that each drug influenced the morphology of the polyethylene glycol (PEG). The enthalpies and melting points of the solidus components of the dispersions' carriers were initially reduced after preparation, but on storage these increased. The particle sizes of the drugs dispersed in the PEGs increased on storage. The changes in dissolution after storage of triamterene or temazepam dispersions were smaller for dispersions in PEG 1500 than for dispersions in PEGs of higher molecular weight (PEG 2000, PEG 4000 or PEG 6000) in which the reduction in dissolution was particularly marked during the first month of storage. The rank order of changes in dissolution were PEG 1500 ? PEG 2000 < PEG 4000 ~ PEG 6000.  相似文献   
992.
Background: The study reviews the anticancer properties of naturalisoflavones which occur in especially high concentration in soybeans. Itconsiders the suitability of soybean products for clinical trials aiming toreduce the progression of breast cancer.Methods: Evidence is reviewed that plant isoflavones such asgenistein show cytostatic activity against human mammary cancer cell linesin vitro and can also suppress carcinogen-induced mammary cancer inyoung and mature rats.Results: Plant isoflavones are converted in the bowel to compoundswith potential antioestrogenic and antioxidative properties. These compoundsshow cytostatic activity for both oestrogen receptor-positive and negativehuman mammary cancer cell lines, and also inhibit growth and progress of therat mammary cancer model. The high content of soybean products in the diet ofAsian women has been postulated as one reason for their relatively low breastcancer incidence.Conclusion: Preclinical studies suggest that soybean products begiven priority for clinical trials in breast cancer protection. A pilot studycould test soy protein supplements as long-term adjuvant dietary treatmentafter primary surgery for early breast cancer, looking for a decrease in therisk of recurrence or of second primary tumours.  相似文献   
993.
The enzyme O6-methylguanine-DNA methyltransferase repairs alkylation- induced DNA damage, O6-methylguanine and O4-methylthymine, the former being formed more frequently. Previously, by means of gene targeting, we generated mice in which alleles for methyltransferase were disrupted. We now use these mouse lines, which are totally deficient in methyltransferase activity, to examine protective effects of the enzyme against tumor formation. In gene-targeted female mice given an i.p. injection of 5 mg/kg of dimethylnitrosamine, a larger number of liver and lung tumors occurred, as compared with normal female mice treated in the same manner. In male mice given a lower dose of carcinogen, the difference between normal and gene-targeted mice was statistically insignificant although more tumors did form in the gene-targeted mice. Methyltransferase apparently afforded protection from nitrosamine- induced tumorigenesis.   相似文献   
994.
The aim of this study was to investigate retrospectively the efficacy of expandable metallic stents (EMSs) for severe respiratory distress in patients with central airway obstruction. Twenty patients with central airway obstructions were treated with an EMS. An intraluminal stricture was present in 15 and an extraluminal stricture in 5 patients. Of the 15 patients with intraluminal stenosis, 11 exhibited symptomatic improvement. All 11 patients had tumor infiltration occupying less than 50% of the endoluminal diameter. The other four patients with intraluminal stenosis had tumor infiltration occupying > 50% of the endoluminal diameter and demonstrated no improvement. All five patients with extraluminal stenosis were improved. EMS is useful for an extraluminal stricture in the central airway and the effect of EMS for intraluminal stenosis is related to the degree of infiltration and of tumor progression itself.   相似文献   
995.
The biodistribution of two recently developed tumour markers, trimethylated (CP(Me)3) and trimethoxylated (CP(OMe)3) carotenoporphyrin, was investigated by means of laser-induced fluorescence (LIF) after i.v. injection into 38 tumour-bearing (MS-2 fibrosarcoma) female Balb/c mice. At 3, 24, 48 or 96 h after administration, the carotenoporphyrin fluorescence was measured in tumoral and peritumoral tissue, as well as in the abdominal, thoracic and cranial cavities. The fluorescence was induced by a nitrogen laser-pumped dye laser, emitting light at 425 nm, and analysed by a polychromator equipped with an image-intensified CCD camera. The fluorescence was evaluated at 490, 655 and 720 nm: the second and third wavelengths represent the carotenoporphyrin (CP)-related peaks, whereas the first one is close to the peak of the tissue autofluorescence. The tumour and the liver were the two tissue types showing the strongest carotenoporphyrin-related fluorescence, whereas the cerebral cortex and muscle consistently exhibited weak substance-related fluorescence. In most tissue types, the fluorescence intensities decreased over time. A few exceptions were observed, notably the liver, in which the intensity remained remarkably constant over the time period investigated.  相似文献   
996.
Zusammenfassung Zahlen zur H?ufigkeit von Herztumoren im operativen Krankengut liegen bisher für die Bundesrepublik Deutschland nicht vor. Um einen entsprechenden überblick für das Jahr 1996 zu erhalten, wurde allen 77 herzchirurgischen Zentren der Bundesrepublik Deutschland ein standardisierter Fragebogen zugesandt. Daten von 65 der 77 Herzzentren (=84%) waren schlie?lich verfügbar: 187 Patienten waren wegen Myxomen, lediglich 44 wegen nichtmyxomat?sen Tumoren, davon 28 wegen malignen prim?ren oder sekund?ren Herztumoren, operiert worden. Im Jahr 1996 waren somit 0,32% (231/72 763) der Eingriffe mit Herz-Lungen-Maschine (erfa?t 72 763 von insgesamt 87 372) wegen eines Herztumors vorgenommen worden. Ausgehend von diesen operativen Daten liegt die Inzidenz ausschlie?lich der prim?ren Tumoren des Herzens zumindest bei 3 Tumoren pro 1 Million Einwohner pro Jahr (253 Tumoren/81,814 Millionen Einwohner). Wenn auch kleine Tumoren asymptomatisch und unentdeckt bleiben k?nnen, wird heute doch die Mehrzahl prim?rer kardialer Tumoren durch Echokardiographie, Computer- und Kernspintomographie bereits zu Lebzeiten des Patienten diagnostiziert, und diese Patienten werden in aller Regel einer Operation zugeführt. Somit werden gut 0,3% aller Eingriffe mit Herz-Lungen-Maschine in Deutschland wegen Herztumoren durchgeführt, wobei es sich weit überwiegend um Myxome handelt. Eingegangen: 23. September 1997, Akzeptiert: 11. Februar 1998  相似文献   
997.
998.
Background: Among gastric restrictive operations, the procedure of choice is still controversial. The aim of this study is to compare the results of two different gastric restrictive procedures: vertical banded gastroplasty (VBG) and stoma adjustable silicone gastric banding (ASGB). Methods: Between 1991 and 1996, 51 patients were treated surgically for morbid obesity: 27 underwent VBG and 24 underwent ASGB. Preoperative body weight (BW), body mass index (BMI) and percentage of ideal body weight (% IBW) were (mean ± SD): 145.7 ± 45.3 kg; 53.9 ± 15.9 kg/m2; 249.1 ± 73.5% respectively in the VBG group. Corresponding figures for the ASBG group were 132.5 ± 22.7 kg; 46.9 ± 7.8 kg/m2 and 207.2 ± 35.0%. Results: In the VBG group, the median follow-up period was 26 months (range: 7-47). Eighteen months after the operation BW, BMI, % IBW and percentage of excess weight loss (% EWL) were 85.5 ± 26.8 kg, 31.9 ± 9.8 kg/m2, 145.4 ± 43.9% and 74 ± 1% respectively. Complications included incisional hernia (n = 1), and bowel obstruction (n = 1). One patient died of acute myocardial infarction on the third postoperative day. In the ASGB group, median follow-up time was 19.7 months (range: 18-26). At 18 months postoperation BW, BMI, % IBW and % EWL values were 86.6 ± 20.6 kg 30.6 ± 6.6 kg/m2 140.6 ± 29.3% and 64 ± 1% respectively. Gastric wall erosion occurred in two patients and the bands had to be removed. These patients underwent VBG 6 months later. Complications encountered in this group were incisional hernia (n = 1), outlet stenosis and reflux esophagitis (n = 1), reservoir leakage (n = 1) and gastrointestinal bleeding (n = 1). Two patients died of pulmonary embolism and acute gastrointestinal bleeding. Conclusions: Weight reduction was not statistically significant between the two groups. ASGB was easier to perform and less invasive than VBG.  相似文献   
999.
Recurrent dislocation of the patella and the Goldthwait operation   总被引:1,自引:0,他引:1  
In this study 17 patients with recurrent dislocation of the patella were followed up 10 years after their Goldthwait operation. The subjective and clinical findings were excellent or good in 70%. X-radiographs indicated osteoarthritis of the femoropatellar joint in 60%. Concerning the aetiopathological factors, we found an increased external torsion of the afflicted extremity (measured by computed tomography).  相似文献   
1000.
Bone mineral density in patients with atopic dermatitis   总被引:1,自引:0,他引:1  
With the aim of evaluating the systemic effect of glucocorticoids (GCs), we measured bone mineral density (BMD) in 29 adult patients with chronic atopic dermatitis. BMD was measured in the lumbar spine and in the left femoral neck using dual–energy X–ray absorptiometry (DEXA). In the right calcaneus. BMD was measured using broad–spectrum ultrasound attenuation (BUA). For BMD, the patients with dermatitis did not differ from healthy controls. We did not find any statistically significant correlation between BMD and single risk factors, such as the barrier function of the skin (P = 0.08), the duration of the dermatitis (P = 0.58), and the use of oral GCs (P = 0.27) and potent topical GCs (P = 0.10). However, selected patients with severe disease, needing topical GCs of higher potency than hydrocortisone (HC), had lower values for lumbar BMD than the patients who had not used these preparations (–1.0 vs. +0.1 SD; P = 0.026). The lower lumbar BMD in this group could be explained by a long-term systemic effect of GCs.  相似文献   
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