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1.
Lung cancer is the leading cause of cancer deaths in both men and women in the United States. Treatment depends on the type and stage of lung cancer. For stage I and II cancer, surgery is usually the treatment of choice. Radiation therapy is used in patients who are considered poor risks for surgical resection. Intraoperative brachytherapy is an effective alternative to external irradiation in this group of patients. From 1958 to 1984, 55 patients with non-small-cell lung cancer were explored at Memorial Sloan Kettering Cancer Center and found to have surgical stage I or II tumors, which were considered to be unresectable mainly because of severe obstructive pulmonary disease precluding adequate resection. All these patients were treated with intraoperative brachytherapy at the time of the thoracotomy. Forty-four percent of these patients received in addition external irradiation, mainly to the mediastinum. The overall 5-year survival calculated by the Kaplan-Meier Method was 32%, and the local disease-free survival was 63%. Cox regression multivariant analysis demonstrated that there is a distinct subgroup with a better prognosis based on tumor site and patient's age--ie, patients who were younger than 58 years of age and had right-side lesions.  相似文献   
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Simian virus 40 (SV40) is a monkey virus that was administered to human populations by contaminated vaccines which were produced in SV40 naturally infected monkey cells.  相似文献   
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Testicular biopsy specimens from infertile men (sperm count, less than 10(6)/ml) were evaluated on 1-micron thick sections, and counts of stem cells and differentiated spermatogonia, primary spermatocytes, early and late spermatids, and Sertoli cells were compared to counts in six fertile men. Biopsy specimens were also compared for the appearance of seminiferous tubule wall, blood vessels, and interstitium. Infertile men were grouped according to the following diagnoses: hypospermatogenesis (n = 5), spermatocyte arrest of spermatogenesis (n = 5), and obstruction of the genital tract (n = 7). A low productivity of spermatogenesis in cases of hypospermatogenesis appeared to be due to an exaggerated degeneration of primary spermatocytes and to a yield of abnormal spermatids. A block of meiosis in spermatocyte arrest was associated with a degeneration of primary spermatocytes and with a reduced number of staminal spermatogonia. Abnormal spermiogenesis was observed in cases of obstruction of the genital tract and was associated with an increase in stem cell spermatogonia. A thickening of seminiferous tubule and blood vessel walls could be responsible for the limited functional capacity of Sertoli cells, causing altered spermiogenesis in cases of excretory azoospermia. A severe primitive failure of Sertoli cells in secretory oligoazoospermia could account for a deranged maturation and degeneration of premeiotic and postmeiotic germ cells.  相似文献   
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BACKGROUND: Recent studies evaluated the technique of direct coronary stenting as compared to stenting-after-predilation in selected anatomic and clinical settings. However, the impact of direct stenting in routine interventional practice remains poorly elucidated. METHODS: From April 1999 to March 2001, all percutaneous coronary interventions performed at our Center were prospectively analyzed to determine the frequency of direct stenting, the success rate and the variables associated with its utilization. RESULTS: 1151 lesions were treated in 835 procedures. Stenting was attempted in 835/1151 lesions (72.5%), 309 (37%) with direct stenting and 526 (63%) with stenting-after-predilation. Direct stenting was successful in 300/309 (97%) and stenting-after-predilation in 515/526 (98%). The success rate of direct stenting was significantly lower in small vessels (< or = 2.75 mm) (89.2 vs 98.5%, p = 0.005). Patients treated with direct stenting were younger (63 +/- 11 vs 65 +/- 11 years, p = 0.024). Direct stenting was preferentially used in saphenous vein grafts and at the ostium of the left anterior descending coronary artery, while it was avoided in bifurcation lesions and with increasing calcium burden. Operators with a caseload > 140 interventions per year were significantly more likely to perform direct stenting than less experienced operators (p = 0.017). In direct stenting, the total contrast medium and the fluoroscopy and procedural times were all significantly (p < 0.0001) lower than those observed in case of stenting-after-predilation. CONCLUSIONS: Direct coronary stenting is currently performed in about one third of the overall caseload. Variables pertaining to the operator's experience, lesion morphology and length, vessel size, and the clinical presentation are all important factors determining the selection of candidates suitable for direct stenting.  相似文献   
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Certain 1,2,3-triazole derivatives were prepared and tested for their ability to displace [3H]diazepam that was bound to bovine brain membrane protein. All the tested compounds are essentially lacking in this ability, except for B.1, which inhibited binding of [3H]diazepam in 50% of the trials at 2.5 microM. The structure of B.1, with a 1,2,3-triazole ring with acidic properties, supports the hypothesis proposed for binding to the benzodiazepine receptor site. Comparison of B.1 with 1,2,3-triazole derivatives bearing a bicyclic substituent in position 1 of the heterocyclic ring suggests that a high steric hindrance increases the affinity of a compound for the benzodiazepine receptor.  相似文献   
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A Martini  G Lenti 《Pédiatrie》1991,46(2):153-160
The treatment of juvenile chronic arthritis requires the integration of various professionals (pediatrician, physiotherapist, orthopedic surgeon, ophthalmologist). The therapeutic program is targeted to control the inflammation with drugs and to preserve joint function with physiotherapy. Since juvenile chronic arthritis is clinically heterogeneous, the natural course and the possible complications which characterize each clinical form must be taken into account.  相似文献   
10.
The detection of some types of aneuploidy in human spermatozoacan be based on the use of the fluorescence in-situ hybridizationtechnique (FISH). One of the crucial steps for FISH is to achievea proper decondensation and denaturation of the DNA in the specimen,so as to obtain efficient hybridization results. However, afterDNA decondensation the morphology of sperm heads is partly distortedand the majority of the tails is lost. This situation leadsto problems in the distinction between disomic and diploid spermatozoa,as well as between abnormal spermatozoa and somatic cells. Double-and triple-target FISH can partly solve this discriminationproblem. To improve these procedures we adapted the steps ofdecondensation and visualization of the single sperm cells.Firstly, DNA decondensation with 25 mM dithiothreitol in 1 MTris at pH 9.5 resulted in sperm cells with intact morphologyof both the head and the tail, and allowed efficient single-,double- and triple-target ISH to be performed. Secondly, weapplied a novel detection method, based on enzyme immunocyto-chemicalreactions, with coloured precipitation products. Thirdly, thisISH procedure was combined with Diff-Quik staining and bright-fieldmicroscopy. This absorption method has the advantage of a permanentsignal, and the adapted cytoplasmic staining of the sperm plasmamembrane allows the visualization of the outline of the singlespermatozoon. Using this approach, therefore, it is possibleto discriminate between disomic, diploid and abnormal spermatozoa,somatic cells and spermatozoa that overlap, because the morphologyof the cells is not distorted and the tails of the spermatozoaare intact and properly visualized.  相似文献   
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