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1.
The effects of hormonal ablation, estrogen, estrogen-derived cytotoxic agent, and estrogen antagonist therapies used clinically were evaluated on in vitro colony formation, in vivo growth, and lymphatic and pulmonary metastasis of the PAIII tumor. Ventral prostatic and seminal vesicle weights were evaluated in the same animals to assess androgen-related responses. Estradiol, estramustine phosphate, and testosterone had no effects on PAIII colony formation in vitro. Castration, hypophysectomy, estradiol benzoate, and estramustine phosphate treatment of PAIII-bearing Lobund Wistar rats produced significant (P less than 0.05) regression of male accessory sex organs. Of these treatments, only hypophysectomy had significant (P less than 0.05) inhibitory effects on primary PAIII growth and lymphatic and pulmonary metastasis. LY117018 [6-hydroxy-2-(p-hydroxyphenyl)benzo(b)thien-3-yl-p-2-(l-pyrrolidin yl)ethoxy phenyl ketone] has antiestrogenic activity but produces no significant agonist responses. LY117018 had no effect upon PAIII colony formation in vitro. Following s.c. implantation of PAIII cells, LY117018 (2.0, 10.0, or 20.0 mg/kg s.c.) had no effect on primary tumor growth in the tail. In vitro LY117018 administration produced marked antimetastatic effects. In a dose-dependent manner, LY117018 inhibited PAIII metastasis to the gluteal (97%) and iliac lymph nodes (88%) (P less than 0.05 for both). LY117018 also maximally inhibited pulmonary metastasis by 86% (P less than 0.05). Maximal regression of 42% for ventral prostatic and 35% for seminal vesicle weights were also seen after LY117018 administration (P less than 0.05 for both). Co-administration of estradiol benzoate had no antagonistic effect upon the antitumor responses produced by LY117018. The mechanism of action of LY117018 is not known. The failure of estradiol benzoate to affect PAIII growth and metastasis supports the contention that the responses to LY117018 are not attributable to simple antagonism of estrogen action. LY117018 may be exerting its antitumor effects through autocrine, paracrine, or endocrine mechanisms. LY117018 represents a class of agents with potential utility in treating metastatic cancer of the prostate.  相似文献   
2.
Overview of experience of Tanzer's group with microtia   总被引:1,自引:0,他引:1  
A review of our patients since Dr. Tanzer's retirement in 1970 shows good and lasting results after reconstruction of microtia using autogenous cartilage frameworks and staged procedures. There has been no evidence of shrinkage or distortion of the cartilage in any of our own patients, and the majority of them are pleased with their ears. With a cooperative and well-motivated patient and surgeons who are skilled and experienced in the procedure, ears can be made with a relatively normal size, shape, and position to match closely the other side. We continue to feel strongly that autogenous cartilage is the safest and best material to use for the ear framework. At some time in the future the body may be taught to accept homografts as if they were its own tissue, and allografts may be available that are tolerated as well as living tissue. Until then we will rely on autogenous tissue and our present techniques, which have produced long-lasting good results. Altogether the combined experience with ear reconstruction of Tanzer's group at the Dartmouth-Hitchcock Medical Center spans more than 30 years.  相似文献   
3.
An agar medium for selective recovery and enumeration of Streptococcus mutans was developed as an alternative to mitis salivarius-bacitracin (MSB) agar. Combinations of dyes, antibiotics, and tellurite were added to a nonselective medium which, because of its sucrose content, allowed easy recognition of S. mutans colonies. Candle jar incubation for 2 days, by comparison with anaerobic incubation, reduced background flora but did not diminish S. mutans recoveries from clinical samples. Quantitative comparisons were made of the simultaneous recoveries of a number of authentic S. mutans serotype representatives and fresh clinical isolates, using various glucose-sucrose-potassium tellurite-bacitracin (GSTB) formulations and mitis salivarius, MSB, and blood agars. Mitis salivarius counts were not detectably different from blood counts, but counts on MSB were distinctly lower. A formulation of the new medium containing 5% glucose 5% sucrose, 0.001% potassium tellurite, 0.3 U of bacitracin per ml (hence GSTB), and 2% agar gave recoveries nearly equal to those on mitis salivarius agar and much greater than those on MSB. The medium yielded readily recognized S. mutans colonies and facilitated detection of intracellular polysaccharide formers upon flooding with I2 reagent. Freshly isolated serotype c, E, and f colonies could often be distinguished from serotype d and g colonies, a distinction made reliable by testing for intracellular polysaccharide. A study of 300 salivary samples revealed GSTB to give significantly higher recoveries than MSB. About 72% of all samples were substantially underestimated for S. mutans with MSB, and 6.7% of samples were falsely negative for S. mutans with MSB. Recovery of background flora on GSTB was as low or lower than on MSB, and both types of agar could be stored for at least 9 weeks without notable change of selectivity. Thus, GSTB agar appears to be simple and reliable to use and requires no anaerobic incubation. Caution is voiced about interpretation of data previously reported which evaluated S. mutans on MSB agar.  相似文献   
4.
Tanzer DJ  Smith RE 《Cornea》1999,18(6):729-730
PURPOSE: To report the extended clinical course of a case of superficial punctate keratitis of Thygeson. METHODS: A 59-year-old woman with a 40-year history of superficial punctate keratitis of Thygeson is presented, providing a forum to discuss the chronicity of the disease, its treatment, and the potential complications. RESULTS: Our patient has been treated over the years with mild topical corticosteroids, usually with favorable results. Given the chronicity of superficial punctate keratitis of Thygeson, long-term treatment with topical corticosteroids carries the possible side effects of iatrogenic cataract formation and steroid-induced glaucoma, neither of which was seen in our patient. CONCLUSIONS: Superficial punctate keratitis of Thygeson is usually a benign, self-limited disease with exacerbations and remissions. Ophthalmologists must exercise care when using long-term corticosteroid treatment in this condition.  相似文献   
5.
HaCaT keratinocyte cultures were exposed to twelve hydrophilic anthralin derivatives 1 to 12 with substituents at C-1 and C-8 of the anthrone skeleton, of one H at C-10 and of both H's at C-10 by lacton rings. After 3 microM treatment growth was determined by cellular protein content, 3H-thymidine- and 14C-amino-acid-uptake and cytotoxicity by the release of cytoplasmic LDH into the culture medium. In comparison to acetone control (100%) anthralin suppressed mean protein content, as well as DNA- and protein-synthesis to 33, 28, and 21%, respectively, and the drug revealed an enzyme release of 660%. In relation to the parent drug we found similar cell growth inhibitory effects of compounds 4, 6, 8, 9, 10, and 12. Deriv. 4, 8, and 10 were, however, to some extent less cytotoxic than anthralin, whereas deriv. 6, 9, and 12 were in the same range. An extreme suppression of growth parameters which differed from the anthralin effect by a factor 0.5-0.8 was caused by deriv. 11, showing the same cytotoxicity. Deriv. 1, 2, 3, 5, and 7 did not demonstrate any cytotoxicity. Concerning growth parameters, deriv. 2 induced a slight stimulation, deriv. 3 and 7 were completely ineffective, deriv. 1 and 5 induced slightly to moderately inhibited proliferation but both being much less effective than anthralin. These data indicate that the "minimum structure" concept by Krebs and Schaltegger--claiming 1-hydroxy-9-anthrone as a precondition for clinical antipsoriatic potency--is not valid at least in cell-biological tests and point toward possible usefulness of some experimental model compounds as alternative antipsoriatics.  相似文献   
6.
Inhibition of 5-lipoxygenase by anthralin (1) and 41 derivatives is determined: the acids 38 and 39, the lactones 40-42 and 9-anthrone (8) are the most potent inhibitors, the lactone 41 reaching the efficacy of nordihydroguaiaretic acid (NDGA). The results were correlated with the hydrophilic/lipophilic balance of the test compounds and their clinical efficacy as far as known. There is no correlation between the "minimum structure" of Krebs and Schaltegger concerning antipsoriatic activity and the inhibitory effects against 5-lipoxygenase.  相似文献   
7.
BACKGROUND AND AIM OF THE STUDY: Although over 20,000 Edwards-Duromedics valves were implanted worldwide between 1982 and May 1988, use of the valve was voluntarily suspended by the manufacturer in May 1988 on the basis of reported leaflet escapes. In 1990, a modified version was introduced to the market, the Edwards-Tekna. The study aim was to evaluate the short-term outcome with this revised valve. METHODS: Between 1994 and 1998, 137 patients (67 males, 70 females; mean age 36.3+/-9.1 years) underwent heart valve replacement with the Edwards-Tekna prosthesis. Among these patients, 72 had isolated mitral valve replacement, 59 isolated aortic valve replacement, and six double-valve replacement. RESULTS: Early hospital mortality was 0.72% (n = 1). Follow up was 95% complete (129/136 patients discharged from hospital). Mean follow up was 24.9+/-10.5 months (range: 2 to 48 months); total follow up was 282.9 patient-years (pt-yr). Actuarial freedom from complications at two-year follow up and linearized incidence (%/pt-yr) of these events were: late mortality 87.8+/-8.5% (1.77%/pt-yr); thromboembolism 89.8+/-4.9% (2.12%/pt-yr); anticoagulation-related bleeding 97.8+/-1.5% (0.71%/pt-yr); prosthetic valve endocarditis 99.1+/-0.9% (0.35%/pt-yr); valve-related mortality 98.2+/-1.2% (0.71%/pt-yr); and valve-related morbidity and mortality 85.0+/-5.0% (4.24%/pt-yr). There was no structural valve failure such as leaflet escape in this series. Clinically significant hemolysis was not encountered (mean postoperative plasma LDH level 345+/-124 IU/l). Preoperatively, 69% of patients were in NYHA classes III/IV; at two years postoperatively 90% of survivors were in classes I/II. CONCLUSION: The Edwards-Tekna mechanical valve prosthesis has shown excellent overall clinical performance in the short term, though long-term data are needed to confirm its durability.  相似文献   
8.
Digestive Diseases and Sciences - New innovations and increasing utility of endoscopic ultrasound (EUS) are associated with rare but serious risks. We investigate the rates and risk factors for...  相似文献   
9.
10.
In this paper, the investigators report a well documented case of malignant histiocytosis (MH) with a t(2;5)(p23;q35) translocation. A breakpoint in 5q35 appears to be specific, either for the disease or for a subclass of the disease. Additional cases of MH with cytogenetics are needed. This will help to determine if one class of MH or several subclasses can be defined by cytogenetic anomaly(ies).  相似文献   
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