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81.
Abstract: The mean microfibril angle (MFA) of tracheids in Sitka spruce ( Picea sitchensis [Bong.] Carr.) from four provenances was determined by X-ray diffraction. Seeds were from four locations in North America: California, Oregon, Queen Charlotte Islands and Washington. Transplants were planted in 1976 and grown in Ireland (Shillelagh Forest). The mean MFA close to the pith was ca. 22° and decreased to ca. 11° in the outer rings. It was found that the MFA varies strongly not only as a function of the annual ring and the distance from pith but also as a function of the seed origin. Trees of California and Queen Charlotte Islands provenance had a larger mean MFA in general than trees of Washington and Oregon provenance. Also, the shapes of the cell cross sections were determined to some extent from the diffraction patterns. For samples of California and Washington provenance the average thickness of the cellulose crystallites was determined to be about 3.0 nm.  相似文献   
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Background  

The initial steps of stem Leydig cell differentiation into steroid producing progenitor cells are thought to take place independent of luteinizing hormone (LH), under the influence of locally produced factors such as leukaemia inhibitory factor (LIF), platelet derived growth factor A and stem cell factor. For the formation of a normal sized Leydig cell population in the adult testis, the presence of LH appears to be essential.  相似文献   
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We report a method based upon fast atom bombardment mass spectrometry (FAB-MS) and stable isotope dilution techniques for the measurement of urinary trimethylamine (TMA) and trimethylamine N-oxide (TMAOx). TMA is extracted from urine that was spiked with (15)N-labeled TMA. The extracted TMA isotopomers are quaternized with trideuteromethyl iodide and analyzed in FAB-MS with hexaethylene glycol as matrix. TMAOx is measured by evaporation of another sample of the urine spiked with (15)N-labeled TMAOx on the FAB probe and analyzed as for the TMA. The method allows the ready and simple distinguishing of controls and patients with TMAuria, and is useful in monitoring patients with the disorder. We give examples of its use in determining normal control ranges for these metabolites and in evaluating patients.  相似文献   
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The mechanisms regulating oviduct function were investigated. In Experiment 1, porcine oviductal secretory protein (pOSP) mRNA, and pOSP and insulin-like growth factor (IGF-I) in oviductal flushings, decreased through the peri-ovulatory period. In Experiment 2, higher plasma steroids in oviductal veins, ipsilateral (INT), rather than contralateral (OVX), to the remaining ovary in unilaterally ovariectomized gilts, were associated with higher pOSP in INT oviductal flushings. In Experiment 3, oviduct function was assessed as part of a collaborative study in cyclic gilts. Feed restriction in the late, compared to the early, luteal phase reduced estradiol concentrations in oviductal plasma, pOSP mRNA in oviductal tissue, and IGF-I concentrations and pOSP abundance in oviduct flushings. Previous insulin treatment differentially affected oviduct function. These data provide the first direct evidence for effects of previous feed restriction and insulin treatment on the oviduct environment in the peri-ovulatory period, which may contribute to nutritional effects on embryonic survival.  相似文献   
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BACKGROUND: Ustekinumab is a human monoclonal antibody that binds to the p40 subunit of interleukin (IL) 12 and IL‐23 and inhibits their pharmacological activity. To evaluate potential effects of ustekinumab treatment during pregnancy, developmental studies were conducted in cynomolgus macaques. METHODS: Ustekinumab was tested in two embryo/fetal development (EFD) studies and in a combined EFD/pre and postnatal development (PPND) study. In the EFD studies, pregnant macaques (12/group) were dosed with saline or ustekinumab (9 mg/kg IV, 22.5 mg/kg SC, or 45 mg/kg IV or SC during the period of major organogenesis, gestation day [GD] 20–50). Fetuses were harvested on GD100–102 and examined for any effects on development. In the EFD/PPND study, pregnant macaques were injected with saline or ustekinumab (22.5 or 45 mg/kg SC) from GD20 through lactation day 33. Infants were examined from birth through 6 months of age for morphological and functional development. Potential effects on the immune system were evaluated by immunophenotyping of peripheral blood lymphocytes and immunohistopathology of lymphoid tissues in fetuses and infants and by T‐dependent antibody response (TDAR) to KLH and TTX and by DTH response in infants. Ustekinumab concentrations were measured in serum from dams, fetus, and infants and in breast milk. RESULTS: Ustekinumab treatment produced no maternal toxicity and no toxicity in the fetuses or infants, including no effects on the TDAR or DTH responses. Ustekinumab was present in serum from GD100 fetuses and was present in infant serum through day 120 post‐birth. Low levels of ustekinumab were present in breast milk. CONCLUSIONS: Exposure of macaque fetuses and infants to ustekinumab had no adverse effects on pre‐ and postnatal development. Birth Defects Res (Part B) 89:351–363, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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