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51.
J M Vasquez M A Winer R L Ax W R Boone 《American journal of obstetrics and gynecology》1989,160(1):20-26
The purpose of our research was to determine whether heparin-binding characteristics of human spermatozoa are related to fertilizing potential, as determined by the hamster egg in vitro penetration assay. Penetration rates were standardized (hamster egg in vitro penetration assay index) by comparison with semen from fertile controls in each bioassay. Saturation of heparin-binding domains was achieved in 100% of raw ejaculates (prewash), but in only 53% of "swim-up" (postwash) samples. The dissociation constants ranged from 0.31 to 48.75 nmol/10(6) cells, and binding site concentrations from 0.47 to 20.82 x 10(17) binding sites/cell. Heparin-binding affinity was significantly greater in prewash compared with postwash samples (p less than 0.01). In prewash samples the number of binding sites differed significantly between subjects having low and high penetration indices (5.67 +/- 1.05 vs 2.01 +/- 0.34 x 10(17) binding sites/cell, p less than 0.05). In prewash samples, binding affinity for heparin significantly correlated with hamster egg in vitro penetration assay indices (R2 = 0.142, p less than 0.05). In contrast, the number of binding sites in prewash samples was negatively correlated with hamster egg in vitro penetration assay indeces (R2 = 0.201, p less than 0.05). These data indicate that the heparin-binding assay may prove to be a rapid, sensitive, and inexpensive means of assessing fertilizing potential of human spermatozoa. 相似文献
52.
Columnar organization and reciprocity of commissural connections in cat primary auditory cortex (AI) 总被引:2,自引:0,他引:2
The laminar distribution and reciprocity of commissural axon terminals and cells of origin in cat primary auditory cortex (AI) were studied after injections of tritiated proline combined with horseradish peroxidase in the middle ectosylvian gyrus. Terminal fields were found in every cortical layer in the contralateral AI, and they were characterized quantitatively. The largest concentration of silver grains was in layer III (about 25% of the total number of silver grains) and, to a lesser extent, in layers V, VI, and I (some 18% of the total in each layer). The labeling in layer I was concentrated in its deeper half, while the labeling in the other layers was more homogeneous. Layer IV had the least labeling, followed by layer II, each receiving about 10% of the total. The labeling was always heaviest over the neuropil and lightest over neuronal perikarya. Commissural terminal fields formed radial patches oriented perpendicularly to the pia, and averaging 543 micron in width. There was consistently three times more silver grains in a patch than in an inter-patch area. However, the number of silver grains in an inter-patch area was always significantly above background, indicating a possible commissural projection to these zones as well. The patches of commissural terminal fields formed bands oriented across AI and running in a caudoventral to rostrodorsal direction. Strict reciprocity between the commissural cells of origin and terminal fields was not found at the light microscopic level when adjacent sections, corrected for differential shrinkage, were compared. Often, patches of terminal fields were free of retrogradely labeled cells and, conversely, there were patches of labeled cells without an overlying commissural terminal field. The terminal fields connected homotopic regions of the contralateral AI, and every region of AI received commissural innervation, unlike the primary somatic sensory and visual cortex, where large zones receive only a few commissural afferents. The more complete pattern of interhemispheric connectivity in auditory cortex is in contrast to the less continuous commissural representation in other sensory neocortical fields. Perhaps this pattern contributes to the anatomical representation of binaurality in auditory cortex. 相似文献
53.
Liposome-encapsulated doxorubicin compared with conventional doxorubicin in a randomized multicenter trial as first-line therapy of metastatic breast carcinoma 总被引:15,自引:0,他引:15
Harris L Batist G Belt R Rovira D Navari R Azarnia N Welles L Winer E;TLC D- Study Group 《Cancer》2002,94(1):25-36
BACKGROUND: The objective of this study was to compare the efficacy and toxicity of the liposome-encapsulated doxorubicin, TLC D-99 (Myocet, Elan Pharmaceuticals, Princeton, NJ), and conventional doxorubicin in first-line treatment of metastatic breast carcinoma (MBC). METHODS: Two hundred twenty-four patients with MBC and no prior therapy for metastatic disease were randomized to receive either TLC D-99 (75 mg/m(2)) or doxorubicin (75 mg/m(2)) every 3 weeks, in the absence of disease progression or unacceptable toxicity. The primary efficacy endpoint was response rate. Responses were assessed using World Health Organization criteria and were required to be of at least 6 weeks' duration. The primary safety endpoint was cardiotoxicity. Cardiac function was monitored by multiple-gated radionuclide cardioangiography scan, and the left ventricular ejection fraction (LVEF) was scored at a central laboratory. Patients were removed from study if LVEF declined 20 or more EF units from baseline to a final value of greater than or equal to 50%, or by 10 or more units to a final value of less than 50%, or onset of clinical congestive heart failure (CHF). RESULTS: Median age was 54 years in both treatment groups. All relevant prognostic factors were balanced, with the exception that there were significantly more progesterone receptor positive patients in the doxorubicin-treated group. Protocol-defined cardiotoxicity was observed in 13% of TLC D-99 patients (including 2 cases of CHF) compared to 29% of doxorubicin patients (including 9 cases of CHF). Median cumulative doxorubicin dose at onset of cardiotoxicity was 785 mg/m(2) for TLC D-99 versus 570 mg/m(2) for doxorubicin (P = 0.0001; hazard ratio, 3.56). The overall response rate was 26% in both treatment groups. The median TTP was 2.9 months on TLC D-99 versus 3.1 months on doxorubicin. Median survival was 16 versus 20 months with a nonsignificant trend in favor of doxorubicin (P = 0.09). Clinical toxicities, commonly associated with doxorubicin, appeared less common with TLC D-99, although the difference was not statistically significant. There was only one report of palmar-plantar erythrodysesthesia (Grade 2) with this liposomal formulation of doxorubicin. CONCLUSIONS: Single-agent TLC D-99 produces less cardiotoxicity than doxorubicin, while providing comparable antitumor activity. 相似文献
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56.
Eric P Winer Clifford Hudis Harold J Burstein Rowan T Chlebowski James N Ingle Stephen B Edge Eleftherios P Mamounas Julie Gralow Lori J Goldstein Kathleen I Pritchard Susan Braun Melody A Cobleigh Amy S Langer Judy Perotti Trevor J Powles Timothy J Whelan George P Browman 《Journal of clinical oncology》2002,20(15):3317-3327
OBJECTIVE: To conduct an evidence-based technology assessment to determine whether the routine use of anastrozole or any of the aromatase inhibitors in the adjuvant breast cancer setting is appropriate for broad-based conventional use in clinical practice. POTENTIAL INTERVENTIONS: Anastrozole, letrozole, and exemestane. OUTCOMES: Outcomes of interest include breast cancer incidence, breast cancer-specific survival, overall survival, and net health benefit. EVIDENCE: A comprehensive, formal literature review was conducted for relevant topics and is detailed in the text. Testimony was collected from invited experts and interested parties. The American Society of Clinical Oncology (ASCO)-prescribed technology assessment procedure was followed. BENEFITS/HARMS: The ASCO panel recognizes that a woman and her physician's decision regarding adjuvant hormonal therapy is complex and will depend on the importance and weight attributed to information regarding both cancer and non-cancer-related risks and benefits. CONCLUSION: The panel was influenced by the compelling, extensive, and long-term data available on tamoxifen. Overall, the panel considers the results of the Arimidex (anastrozole) or Tamoxifen Alone or in Combination (ATAC) trial and the extensive supporting data to be very promising but insufficient to change the standard practice at this time (May 2002). A 5-year course of adjuvant tamoxifen remains the standard therapy for women with hormone receptor-positive breast cancer. The panel recommends that physicians discuss the available information with patients, and, in making a decision, acknowledge that treatment approaches can change over time. Individual health care providers and their patients will need to come to their own conclusions, with careful consideration of all of the available data. (Specific questions addressed by the panel are summarized in Appendix 3.) VALIDATION: The conclusions of the panel were endorsed by the ASCO Health Services Research Committee and the ASCO Board of Directors. 相似文献
57.
Innervation of supporting cells in the apical turns of the guinea pig cochlea is from type II afferent fibers 总被引:3,自引:0,他引:3
Fechner FP Nadol JB JR Burgess BJ Brown MC 《The Journal of comparative neurology》2001,429(2):289-298
The outer supporting cells in the apical turns of the guinea pig cochlea receive a dense innervation. Our previous study (Fechner et al. [1998] J. Comp. Neurol. 400:299-300) suggested that this innervation of the Deiters' and Hensen's supporting cells was not derived from efferent fibers of the olivocochlear bundle, but its origin has not been further specified. To test the hypothesis that the innervation was afferent in origin, we traced apical afferent fibers that were retrogradely labeled by extracellular injections of horseradish peroxidase. Labeled afferent fibers were of two types: type I fibers contacted inner hair cells, whereas type II fibers crossed the tunnel and contacted outer hair cells. Significantly, most of the type II fibers also formed branches to the outer supporting cells. Although a few olivocochlear efferent fibers formed such branches, counts indicated that the overwhelming majority of the branches were produced by type II afferent fibers. These branches were not produced by basal type II fibers. Apical type II fibers also differed from basal fibers by having shorter lengths, spiraling both apically and basally, and contacting all three rows of outer hair cells. These innervation differences suggest differences in the ways that information from outer hair cells is processed in the apex versus the base of the cochlea. 相似文献
58.
Intrauterine infection induces programmed cell death in rabbit periventricular white matter 总被引:11,自引:0,他引:11
Debillon T Gras-Leguen C Vérielle V Winer N Caillon J Rozé JC Gressens P 《Pediatric research》2000,47(6):736-742
An association between chorioamnionitis and periventricular leukomalacia has been reported in human preterm infants. However, whether this link is causal has not been convincingly established, and the underlying molecular mechanisms remain unclear. The objective of this study was to establish a reproducible model of cerebral white matter disease in preterm rabbits after intrauterine infection. Escherichia coli was inoculated into both uterine horns of laparotomized pregnant rabbits when gestation was 80% complete. The fetuses were delivered by cesarean section and killed 12, 24, or 48 h after the inoculation. Programmed cell death in the white matter was evaluated by hematoxylin-eosin-saffron staining and in situ fragmented DNA labeling (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling). In a first group of 14 pregnant rabbits not treated with antibiotics, all fetuses delivered 48 h after inoculation were stillborn, whereas fetuses extracted 12 or 24 h after inoculation were alive. No significant cell death was detected in the live fetuses compared with the control noninfected rabbits. In a second group of five pregnant rabbits treated with ceftriaxone initiated 24 h after the inoculation and continued until cesarean section was performed 48 h after inoculation, 13 fetuses were alive, but all showed evidence of extensive programmed cell death in the white matter by hematoxylin-eosin-saffron staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling. White matter damage became histologically detectable only 48 h after inoculation. Three of the 13 brains displayed periventricular white matter cysts mimicking human cystic periventricular leukomalacia. The high reproducibility of white matter damage in our model should permit further studies aimed at unraveling the molecular mechanisms of periventricular leukomalacia. 相似文献
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60.
ABSTRACT We report an unusual case of bilateral chronic conjunctivitis and corneal scarring in a boy with X-linked hypogammaglobulinaemia (XLH) who did not respond to the usual antibacterial and antiviral therapy. An immunofluorescence test for Chlamydia trachomatis from an eye swab was strongly positive. Within days of commencement of local and systemic tetracycline therapy, he showed marked improvement. Since conjunctival follicle formation, which depends on the presence of a B-cell population, may not occur in XLH, clinical examination in chlamydia conjunctivitis may be misleading and lead to a delay in diagnosis and treatment with resulting corneal complications, unless laboratory evidence of chlamydia infection is specifically sought. 相似文献