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241.
Hormone concentrations in the serum and seminal plasma of 15 normozoospermic, 17 excretory azoospermic and 14 secretory azoospermic men were measured. The results indicate that: (a) serum FSH and LH levels are markedly elevated in secretory azoospermia, as compared with excretory azoospermia and normozoospermia; (b) serum 17 alpha-hydroxyprogesterone levels are somewhat raised in secretory azoospermia as compared with excretory azoospermia and normozoospermia; (c) serum testosterone levels are lower in both types of azoospermia with respect to normozoospermia; (d) in secretory azoospermia the oestradiol serum levels are relatively high and dihydrotestosterone serum levels relatively low, whereas the serum levels of these hormones in excretory azoospermia are similar to those in normozoospermic men; (e) in the seminal plasma of azoospermic patients the levels of prolactin, progesterone, testosterone, dihydrotestosterone and oestradiol were depressed, but only dihydrotestosterone levels could be of value in differentiating types of azoospermia because they are lower in secretory azoospermia. We suggest that the measurement of FSH, LH, 17 alpha-hydroxyprogesterone, dihydrotestosterone and oestradiol in serum and dihydrotestosterone in seminal plasma may be used in the differential diagnosis between secretory and excretory azoospermia when invasive tests are unavailable.  相似文献   
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High pressure liquid chromatography (HPLC) was used to determine 3H-estramustine (estradiol-17β3N-bis-[2-chlorethyl] carbamate), 3H-17β-hydroxy-5α-androstan-3-one (3H-dihydrotestosterone or 3H-DHT), 3H-estradiol-17β (3H-E2) and 3H-3β-hydroxy-5-pregnen-20-one (3H-pregnenolone) binding in 50μ1 of cytosol utilizing a column which separates proteins in the molecular weight range of 2,000 to 70,000 daltons. The rat prostate contains a protein in considerable concentration and with the highest affinity for estramustine (375,000dpm 3H-estramustine per mg. cytosol protein) among the substances tested. Operationally, we have named this protein “estramustine binding protein” (EBP), though it is very likely similar to other previously described prostatic proteins (e.g., α-protein, prostatein, prostatic binding protein). The sensitivity of the HPLC method disclosed EBP-like proteins, but in much lesser concentrations, in some of the other tissues tested. The concentration of these proteins in the human and baboon prostates was much lower (average for the baboon cranial lobe 4800dpm/mg cytosol protein, with a somewhat higher value for the caudal lobe) than that in the rat gland. The amount of the EBP-like protein was higher in prostatic cancer than in that of benign prostatic hypertrophy (BPH) (range 9350 – 25,900 vs. 2200 – 18,900 dpm/mg cytosol protein). In the human, the highest value was found in one normal prostate tested (106,000dpm/mg cytosol protein).  相似文献   
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The complement system can be specifically targeted to tumor cells due to molecular changes on their surfaces that are recognized by complement directly or via naturally occurring antibodies. However, tumor cells often overexpress membrane-bound complement inhibitors protecting them from complement attack. We have previously shown that non-small cell lung cancer (NSCLC) cells, additionally to membrane-bound inhibitors, produce substantial amounts of soluble regulators such as factor I (FI) and factor H (FH). Since low oxygen concentration is associated with rapidly growing solid tumors, we studied how NSCLC cells protect themselves from complement attack under hypoxic conditions. Unexpectedly, mRNA levels and secretion of both FI and FH were significantly decreased already after 24 h exposure to hypoxia while cell viability measured by XTT assay and annexin V/7-AAD staining was affected only marginally. Furthermore, we observed decrease of mRNA level and loss of membrane-bound complement inhibitor CD46 and increased deposition of early (C3b) and terminal (C9) complement components on hypoxic NSCLC cells. All three complement pathways (classical, lectin and alternative) were employed to deposit C3b on cell surface. Taken together, our results imply that under hypoxic conditions NSCLC give up some of their available defense mechanisms and become more prone to complement attack.  相似文献   
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Gradual Thawing Improves the Preservation of Cryopreserved Arteries   总被引:3,自引:0,他引:3  
This study was designed to test a slow, controlled, automated process for the thawing of cryopreserved arteries, whereby specimen warming is synchronized with the warming of its environment. Segments of minipig iliac artery, 4-5 cm in length, were subjected to controlled, automated cryopreservation in a biological freezer at a cooling rate of 1 degrees C/min to -120 degrees C, followed by storage in liquid nitrogen at -196 degrees C for 30 days. Following storage, the arterial segments were subjected to rapid (warming rate of approximately 100 degrees C/min) or gradual (1 degrees C/min) thawing. Thawed specimens were processed for light microscopy and for scanning and transmission electron microscopy, Cell death was determined by the TUNEL method. Metalloproteinase (MMP) expression was estimated by immunohistochemical analysis. Most of the cryopreserved vessels subjected to rapid thawing showed spontaneous fractures, mainly microfractures, whereas these were absent in slowly thawed specimens. In rapidly thawed vessels, the proportion of damaged cells was double that observed in those thawed more gradually. Increased intensity and extent of MMP-2 expression was shown by rapidly thawed specimens. The slow-thawing protocol tested avoids the formation of spontaneous fractures and microfractures and the accumulation of fluid within the arterial wall tissue. This results in improved tissue preservation.  相似文献   
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