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Carpino A; Siciliano L; Petroni MF; De Stefano C; Aquila S; Ando S; Petrone MF$corrected to Petroni MF 《Human reproduction (Oxford, England)》1998,13(1):111-114
Total seminal zinc concentration, seminal zinc fraction bound to high
molecular weight proteins (HMW-Zn%) and zinc content in spermatozoa were
assayed in the ejaculates of 90 asthenozoospermic patients subdivided into
two study groups: normoasthenozoospermics (group I: n = 50) and
oligoasthenozoospermics (group II: n = 40). The zinc concentrations of
patients were compared with those of a control group of donors showing
normal semen parameters. All samples were also investigated for their sperm
membrane functional integrity by the hypo- osmotic swelling test (HOS). The
results showed normal total zinc concentrations but very low HMW-Zn% values
(P < 0.001) in seminal plasma of the two groups of asthenozoospermic
patients compared to the controls. Furthermore higher zinc amounts (P <
0.001) were measured in spermatozoa of oligoasthenozoospermic patients
compared to group I and to the control group. Oligoasthenozoospermics also
displayed a lower HOS score (P < 0.001) compared to the other two
groups. These data suggest that the increased unbound seminal zinc could
contribute to the decrease of sperm motility in normoasthenozoospermic and
oligoasthenozoospermic patients. A further impairment in sperm motility
could occur in the oligoasthenozoospermic patients where the increase of
seminal free zinc was followed by a major zinc uptake by spermatozoa. The
higher intrasperm zinc content in these patients could be a reflection of
their low sperm membrane functionality.
相似文献
94.
Magnuson JE; Brown ML; Hauser MF; Berquist TH; Fitzgerald RH Jr; Klee GG 《Radiology》1988,168(1):235-239
When infection of prosthetic orthopedic implants is suspected, optimal management requires accurate confirmation or exclusion of infection. The authors retrospectively studied 98 patients with possible infection who underwent scanning with indium-111-labeled white blood cells (WBCs) and subsequently underwent surgery within 14 days. At surgery, 50 patients had infections, as determined by means of culture or histologic results. The diagnostic accuracy of In-111 scanning was compared with that of plain radiography, arthrography, three-phase bone scanning, and various clinical and laboratory findings classically associated with infection. Positive findings on In-111 WBC scans and elevated erythrocyte sedimentation rates were found to be the most predictive variables in the diagnosis of septic prostheses (P less than or equal to .001 and P less than or equal to .002, respectively). Likelihood ratio analysis more clearly demonstrated the superiority of In-111 WBC scanning, with positive and negative scans yielding likelihood ratios of 5.0 and 0.16, respectively. 相似文献
95.
Pflugfelder PW; Wendland MF; Holt WW; Quay SC; Worah D; Derugin N; Higgins CB 《Radiology》1988,167(1):129-133
Cardiac-gated magnetic resonance (MR) imaging was performed in rats to determine the effects of manganese ethylenediaminetetraphosphonate (TP). Ten normal rats received Mn-TP in a dose of 50 mumol/kg through a tail-vein injection. Spin-echo MR images were obtained before and every 10 minutes after Mn-TP injection for 1 hour. Cardiac signal intensity (SI) increased more than 70% after Mn-TP injection and remained nearly unchanged 1 hour after injection. Myocardial T1 was 517 +/- 49 msec in eight control rats and 282 +/- 61 msec (P less than .001) in six rats 81 +/- 0 minutes after injection. Nine rats underwent occlusion of the left anterior descending coronary artery prior to MR imaging. Images were obtained before and 15, 30, and 60 minutes after Mn-TP injection. In normal myocardium, SI increased up to 82% and remained elevated for 1 hour. In ischemic myocardium, SI rose 11%, leading to a marked contrast between the two tissue zones. T1 was also different in the two regions: In normal tissue, it was 206 msec +/- 54; in ischemic tissue, 338 +/- 82 (P less than .001). With T1-weighted MR imaging, Mn-TP showed a potential for delineating the jeopardized area after acute myocardial ischemia. 相似文献
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Combined lycopene and vitamin E treatment suppresses the growth of PC-346C human prostate cancer cells in nude mice 总被引:4,自引:0,他引:4
Limpens J Schröder FH de Ridder CM Bolder CA Wildhagen MF Obermüller-Jevic UC Krämer K van Weerden WM 《The Journal of nutrition》2006,136(5):1287-1293
Epidemiologic studies have repeatedly associated a high intake of lycopene and vitamin E with reduced prostate cancer risk. The present study examined the ability of the 2 compounds to reduce tumor growth and prostate-specific antigen (PSA) plasma levels in the PC-346C orthotopic mouse model of human prostate cancer. Three days after intraprostatic tumor injection, NMRI nu/nu mice were administered a daily oral dose of synthetic lycopene [5 or 50 mg/kg body weight (BW)], vitamin E in the form of alpha-tocopheryl acetate (5 or 50 mg/kg BW), a mixture of lycopene and vitamin E (5 mg/kg BW each), or vehicle. Intraprostatic tumor volume and plasma PSA concentrations were measured at regular intervals. Mice were killed when the tumor load exceeded 1000 mm(3) or on d 95 when the study was terminated. Prostate and liver were analyzed by HPLC for lycopene isomers and alpha- and gamma, delta-tocopherol concentrations. None of the single treatments significantly reduced tumor volume. In contrast, combined treatment with lycopene and vitamin E, at 5 mg/kg BW each, suppressed orthotopic growth of PC-346C prostate tumors by 73% at d 42 (P < 0.05) and increased median survival time by 40% from 47 to 66 d (P = 0.02). The PSA index (PSA:tumor volume ratio) did not differ between experimental groups, indicating that PSA levels were not selectively affected. Lycopene was detected only in mice supplemented with lycopene. As in humans, most tissue lycopene was in the cis-isomer conformation, whereas 77% trans-lycopene was used in the dosing material. Liver alpha-tocopherol concentrations were increased in mice supplemented with both 50 mg/kg (226%, P < 0.05) and 5 mg/kg vitamin E (41%, P < 0.05), whereas prostate alpha-tocopherol concentrations were increased only by the higher dose (83%, P < 0.05). Our data provide evidence that lycopene combined with vitamin E may inhibit the growth of prostate cancer and that PSA can serve as a biomarker of tumor response for this treatment regimen. 相似文献
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