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HERMAN TOURNAYE RONNY JANSSENS PAUL DEVROEY RK VAN STEIRTEGHEM 《International journal of andrology》1994,17(1):1-8
In order to evaluate the effects of pentoxifylline on sperm motility and longevity, a controlled in-vitro study was conducted on normozoospermic donor semen samples using the Cellsoft automated system for sperm motility analysis. After incubation and selection, pentoxifylline was found to improve the recovery of spermatozoa and to increase their velocity. In the subgroup of progressively motile spermatozoa, curvilinear velocity was also enhanced. It is concluded that pentoxifylline has an effect on the vigour, but not on the pattern, of sperm motion. Pentoxifylline did not improve the motility characteristics of senescent spermatozoa in normozoospermic sperm samples. Sperm survival, as shown by supra-vital staining, and motility longevity both decreased with time after pentoxifylline treatment. 相似文献
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Membrane fluidity and adrenergic receptor binding were studied in platelets of depressed patients before and during treatment with desmethylimipramine to investigate the relationship between the alpha 2-adrenergic receptor and its membrane environment in depression. Most samples came from a previous study in which we observed higher 3H-para-aminoclonidine (3H-PAC) binding in platelets from depressed patients compared to healthy subjects. Fluidity was measured by steady state diphenylhexatriene (DPH) anisotropy in both purified plasma membranes and in intracellular membrane preparations from platelets. No differences were observed in DPH membrane fluidity, per se, indicating that fluidity changes probably do not underlie either the increased alpha 2-adrenergic receptor binding in depression or the normalization of binding during treatment. However, lower intracellular membrane fluidity was correlated with higher binding to 3H-PAC site-1 in healthy subjects, but not in depressed patients. Thus, during depression there may be a disruption in the normal relationship between the adrenergic receptor and its membrane environment. 相似文献
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The efficacy of two dry cow treatment (DCT) regimens for subclinical Staphylococcus aureus mastitis was evaluated in naturally infected dairy cows. At dry‐off, cows were assigned to two treatment groups by randomized blocks on the basis of parity and somatic cell count (SCC). Two antibiotic DCT regimens were used, namely: (1) a single intramammary infusion containing sodium nafcillin, procaine benzylpenicillin and dihydrostreptomycin; and (2) systemic cefquinome administered intramuscularly, twice at a 24‐h interval. In the intramammary (IMM) treatment group, the S. aureus intramammary infection (IMI) rate was reduced from 40% (56/140 quarters) before dry‐off to 20% (28/140) after calving. Seventy per cent (39/56) of the S. aureus‐positive quarters were negative after calving, and 13% (11/84) of the negative quarters were positive after calving. In the systemic treatment group, the S. aureus IMI rate increased from 39% (29/74 quarters) before dry‐off to 55% (41/74) after calving. Twenty‐eight per cent (8/29) of the S. aureus‐positive quarters were negative after calving and 45% (20/45) of the negative quarters were positive after calving. The odds ratio of an S. aureus‐positive quarter being negative after calving in the IMM group relative to the systemic therapy group was 44.6 (95% confidence interval = 2.1–909.1, P < 0.01). Parity, quarter, milk SCC and N‐acetyl‐β‐D‐glucosaminidase were tested in the model, and were found to have no significant effect on S. aureus cure rates or new IMI rates. The IMM treatment resulted in a higher cure rate compared with that observed in previous studies. The very low cure rate after systemic cefquinome treatment was comparable to the spontaneous cure rate observed in untreated controls in previous studies. The unfavourable results of the cefquinome systemic DCT might reflect inadequate pharmacokinetic properties of the drug regarding poor udder penetration in subclinical mastitis and short antimicrobial effect compared with the IMM treatment. 相似文献
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V. JNSSON H. D. SCHRDER W. TROJABORG T. STAEHELIN JENSEN E. HIPPE M. MRK HANSEN 《Journal of internal medicine》1992,232(2):185-191
A study of 17 patients with autoimmune axonal or demyelinating peripheral neuropathy in combination with M-component is described. The M-component was associated with MGUS (monoclonal gammopathy of undetermined significance) in 12 patients, CLL in one patient, WaldenstrÖm's disease in one patient, and myeloma in three patients. Immunohistological examination with direct and indirect fluorescence showed binding of antibodies to nerve structures of the same class and light chain as seen in the M-component. In five cases of IgM M-component, the demyelinating neuropathy was caused by binding of the IgM M-protein and complement C3b to myelin-associated glycoproteins (MAG). In 12 cases with axonal neuropathy, binding of IgG to the connective tissue of the peri- and endoneurium was found in 50% of cases, IgM in five cases, and IgD in one case. None of the patients had central nervous system (CNS) symptoms. The clinical and therapeutic difficulties are discussed; only two patients with an acute course responded to immunosuppression. A marked co-expression of other autoimmune phenomena is interpreted in the light of cross-reactions between the autoantibody and similar tissue autoantigens. 相似文献
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To assess its reliability as a marker of cardiomegaly in elderly patients, we compared a clinical assessment of heart size with that calculated from chest radiography. In 100 hospitalized subjects of median age 78 years, the apex beat was palpable in only 35% and its palpability declined with increasing age. Even when palpable, the apex beat had low specificity (74%) and sensitivity (69%) as a marker of cardiomegaly and its positive predictive value (69%) and negative predictive value (74%) were poor. The clinical assessment of heart size in elderly hospitalized patients should be interpreted with caution. 相似文献
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Martin C Saran R Leavey S Swartz R 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(6):640-644
Continuous renal replacement therapy (CRRT), such as continuous venovenous hemofiltration, has theoretical advantages over intermittent hemodialysis (IHD) that are related to cardiorespiratory stability, metabolic control, and fluid balance allowing nutritional supplementation. However, retrospective and controlled studies fail to show these advantages because of comorbidity associated with triage to CRRT. To compare outcomes using IHD versus CRRT, we applied published risk stratification models (Cleveland Clinic Foundation, Lohr index, and APACHE II) to the 349 patients with acute renal failure requiring renal replacement therapy at University of Michigan over the 2 year period including 1995 and 1996. The Cleveland Clinic Foundation model best predicted overall mortality, but our CRRT patients had excess, unpredicted mortality that was particularly prominent in the lower risk categories. The Lohr clinical score predicted mortality less accurately but also was associated with higher, unpredicted mortality at lower risk scores among the CRRT patients. APACHE II scores did not predict mortality very well among IHD, CRRT, or the combined group of patients. We conclude that the need for CRRT itself predicts mortality over and above that included in published risk models. Either CRRT is associated with some unidentified morbidity (e.g., treatment associated infection) or, more likely, triage to CRRT is associated with as yet unspecified comorbidity not detected in existing risk stratification schemes. It will be important to address these issues in any future studies evaluating outcome or comparing renal replacement therapy modalities among patients with severe acute renal failure. 相似文献