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991.
F Leonessa V Boulay A Wright E W Thompson N Brünner R Clarke 《Acta oncologica (Stockholm, Sweden)》1992,31(2):115-123
Many breast tumors appear to follow a predictable clinical pattern, being initially responsive to endocrine therapy and to cytotoxic chemotherapy but ultimately exhibiting a phenotype resistant to both modalities. Using the MCF-7 human breast cancer cell line as an example of an 'early' phenotype (estrogen and progesterone receptor positive, steroid responsive, low metastatic potential), we have isolated and characterized a series of hormone-independent but hormone-responsive variants (MIII and MCF7/LCC1). However, these variants remain responsive to both antiestrogens and cytotoxic drugs (methotrexate and colchicine). MIII and MCF7/LCC1 cells appear to mimic some of the critical aspects of the early progression to a more aggressive phenotype. An examination of the phenotype of these cells suggests that some hormone-independent breast cancer cells are derived from hormone-dependent parental cells. The development of a hormone-independent phenotype can arise independently of acquisition of a cytotoxic drug resistant phenotype. 相似文献
992.
993.
994.
The relationship between the immunological and biological activities of thyroid-stimulating hormone (TSH) isoforms present in the three human pituitary preparations 68/38 (1st IRP), 80/558 (2nd IRP) and 63/14 (MRC Research Standard A) was investigated. The isoforms were separated by chromatofocusing. Six peaks of immunoactivity were detected in 80/558, with pI values (means +/- S.E.M.) of 6.6 +/- 0.1, 6.2 +/- 0.1, 5.9 +/- 0.1, 5.5 +/- 0.1, 5.2 +/- 0.1 and 4.9 +/- 0.1. Four peaks, with pI values of 6.8 +/- 0.1, 5.9 +/- 0.1, 5.5 +/- 0.1 and 5.2 +/- 0.1, were observed for 68/38. Standard 63/14 had five peaks, with pI values of 6.9 +/- 0.1, 6.4 +/- 0.1, 5.9 +/- 0.1, 5.4 +/- 0.1 and 4.9 +/- 0.1. For each standard, six fractions around the peak areas and at the top and bottom of the gradient were pooled and microconcentrated to < 1.0 ml. Microconcentrated TSH samples were assayed in three TSH bioassays based upon FRTL-5 thyroid cells, utilizing cyclic AMP accumulation, iodide and thymidine uptake as end-points and standard 80/558 as reference preparation. The more acidic forms of TSH showed a higher biological:immunological (B:I) ratio for cyclic AMP accumulation with, for example, 63/14 having a maximum of 3.7 (pI 4.9) and a minimum of < 0.7 (pI 6.9). In contrast, the maximum and minimum B:I ratios for iodide uptake for 63/14 were 3.8 (pI 6.9) and < 0.8 (pI 4.6), and for thymidine uptake, maximum and minimum ratios were 7.2 (pI 6.9) and 1.1 (pI 4.6) respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
995.
A 28-year-old woman developed numbness and weakness of the hands and arms when she was 8 months pregnant, and weakness worsened gradually. However, weakness started to spontaneously subside immediately after delivery and she felt almost recovered several hours later. But weakness and numbness recurred one week after delivery and she was admitted to our hospital. Neurological examination revealed moderate weakness and disturbance of the deep and cutaneous sensations in the upper and lower extremities, and marked decrease of the deep tendon reflexes. The upper extremities were more severely affected. Nerve conduction study showed marked decrease in the motor conduction velocities. Cerebrospinal fluid showed increase of protein without pleocytosis. Teased preparation of the biopsied sural nerve showed occasional internodal segments with thin myelination, indicating demyelination and remyelination. A diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy was made. Treatment with prednisolone markedly improved the weakness and hyporeflexia as well as the cerebrospinal fluid protein. Postpartum rapid remission may have been produced by rapid increase of endogenous steroid hormone in the blood by its massive excretion during delivery. 相似文献
996.
We present surface anatomy scanning (SAS) image by weighted-summation technique using MRI images in herpes simplex encephalitis. Recently, SAS has been developed as a technique that visualizes brain surface structures. This patient was a 64-year-old male who suffered from aphasia and memory disturbance after herpes simplex encephalitis. He was transferred to our hospital for rehabilitation. Neuropsychological tests showed Wernicke's aphasia and memory impairment. SAS was performed for the purpose of analyzing these neuropsychological deficits, especially the Wernicke's aphasia. In SAS image, sulci were enhanced and gyri were easy to identify clearly. The affected structures disclosed low intensity areas in the entire left temporal lobe, including the superior temporal gyrus. It was clarified that the damage to the left superior temporal gyrus resulted in his Wernicke's aphasia. We think that SAS is very useful for cortical lesion analysis, not only in encephalitis but also in other disorders presenting higher brain dysfunctions. 相似文献
997.
F Suzuki N Miura T Ueda M Minamide K Suzuki H Inomiya T Kotake Y Nishikawa K Yamaguchi H Ito 《Hinyokika kiyo. Acta urologica Japonica》1992,38(2):185-187
A 72-year-old female visited our hospital with the complaint of macroscopic hematuria on Jan. 29, 1990. Cystoscopic examination revealed hematuria flowing out from the left ureteral orifice. A 1 cm mass was found in the left upper calyx by retrograde pyelography (RP). Urine cytology obtained by RP was class IIIb. Later, the mass was found in the left middle calyx by CT. Repeated RP revealed no mass and the wall of the left upper calyx was irregular. Washing cytology from the left renal pelvis was class V. Left total nephroureterectomy was performed on Feb. 2, 1990. Macroscopically, no tumor mass was apparent. Microscopically, transitional cell carcinoma in situ was widely spread from the left renal pelvis to the middle ureter. The preoperative upper calyceal mass was thought to have been a blood clot. At twelve months after the operation, there has been no evidence of tumor recurrence. 相似文献
998.
H. Afsar A. Metin N. Sozduyar M. Salih U. Gulsoy 《International urology and nephrology》1992,24(1):65-68
The authors describe 14 cases of erectile dysfunction. The sites of leakage were detected by duplex or colour flow Doppler
sonography.
Treatment by dorsal vein ligation resulted in fairly good early responses, however, at 4-month follow-up the great majority
of patients returned to the original functional state. 相似文献
999.
Z. S. Meharwal N. Trehan V. M. Kohli V. K. Sharma R. R. Kasliwal A. Mishra V. Kohli A. Jayant 《Indian Journal of Thoracic and Cardiovascular Surgery》1992,8(2):88-91
Between November 1988 and February 1992, 416 patients required coronary endarterectomy for diffuse coronary artery disease.
This constitutes 16.19 per cent of all patients who underwent coronary artery bypass grafting during the same period. A total
of 528 endarterectomies were performed. Four-hundred and twenty-two endarterectomies were performed on right coronary system
and 106 endarterectomies were performed on left coronary system. One-hundred and twelve (26.92%) patients required more than
one endarterectomies.
The hospital mortality was 2.16 percent. 3.37 per cent of patients had perioperative infarction. Intraaortic balloon pump
was required in 1.92 per cent of patients. 5.77 per cent of the patients had significant arrhythmias. The patients have been
followed up for a mean period of 27 months. One-hundred and forty patients were evaluated by exercise multigated radionuclide
angiogram. One-hundred and thirty-four (95.71%) patients showed increase in ejection fraction as compared to preoperative
value. Six (4.29%) patients did not show any significant change while eight (5.71%) patients had fall in ejection fraction.
Postoperative coronary angiogram was done in 44 patients at a mean of 10 months. 89.59 per cent of grafts to the endarterectomised
vessels and 91.67% of grafts to nonendarterectomised vessel were patent. The difference between the two groups was not statistically
significant. 相似文献
1000.
J. O’Byrne S. Eustace M. M. Stephens M. N. M. R. Farahat G. Yanni R. Posten G. S. Panayi S. Sant R. Costello M. Barry J. Hassan C. Feighery B. Bresnihan A. Whelan F. Coakley A. M. de Paor R. B. Reilly E. B. Casey V. J. Tormey G. Kearns K. Gaffney P. J. Freyne M. Callaghan O. FitzGerald D. Veale E. O’Nuallain D. Reen D. Veale M. Farrell O. FitzGerald S. Rogers L. Barnes R. J. Coughlan C. McCarthy M. McDermott D. Hourihane C. O'Morain S. O'Reilly P. Hartley E. Casey L. Clancy F. Mulcahy N. Hall A. Murphy C. Breen D. Kelleher M. Abuzakouk C. O'Farrelly 《Irish journal of medical science》1992,161(6):438-442