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排序方式: 共有363条查询结果,搜索用时 15 毫秒
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Lisa M. Pastore Mindy S. Christianson James Stelling William G. Kearns James H. Segars 《Journal of assisted reproduction and genetics》2018,35(1):17-23
There are large variations in the number of oocytes within each woman, and biologically, the total quantity is at its maximum before the woman is born. Scientific knowledge is limited about factors controlling the oocyte pool and how to measure it. Within fertility clinics, there is no uniform agreement on the diagnostic criteria for each common measure of ovarian reserve in women, and thus, studies often conflict. While declining oocyte quantity/quality is a normal physiologic occurrence as women age, some women experience diminished ovarian reserve (DOR) much earlier than usual and become prematurely infertile. Key clinical features of DOR are the presence of regular menstrual periods and abnormal-but-not-postmenopausal ovarian reserve test results. A common clinical challenge is counseling patients with conflicting ovarian reserve test results. The clinical diagnosis of DOR and the interpretation of ovarian reserve testing are complicated by changing lab testing options and processing for anti-mullerian hormone since 2010. Further, complicating the diagnostic and research scenario is the existence of other distinct yet related clinical terms, specifically premature ovarian failure, primary ovarian insufficiency, poor ovarian response, and functional ovarian reserve. The similarities and differences between the definitions of DOR with each of these four terms are reviewed. We recommend greater medical community involvement in terminology decisions, and the addition of DOR-specific medical subject-heading search terms. 相似文献
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Systemic hematologic effects of PEG-rHuMGDF-induced megakaryocyte hyperplasia in mice 总被引:3,自引:3,他引:3
Ulich TR; del Castillo J; Senaldi G; Kinstler O; Yin S; Kaufman S; Tarpley J; Choi E; Kirley T; Hunt P; Sheridan WP 《Blood》1996,87(12):5006-5015
PEG-rHuMGDF injected daily in normal mice causes a rapid dose-dependent increase in megakaryocytes and platelets. At the same time that platelet numbers are increased, the mean platelet volume (MPV) and platelet distribution width (PDW) can be either decreased, normal, or increased depending on the dose and time after administration. Thus, PEG-rHuMGDF at a low dose causes decreases in MPV and PDW, MGDF at an intermediate dose causes an initial increase followed by a decrease in MPV and PDW, and PEG-rHuMGDF at higher doses causes an increase in MPV and PDW followed by a gradual normalization of these platelet indices. In addition to the expected thrombocytosis after 7 to 10 days of daily injection of high doses of PEG-rHuMGDF, a transient decrease in peripheral red blood cell numbers and hemoglobin is noted accompanied in the bone marrow by megakaryocytic hyperplasia, myeloid hyperplasia, erythroid and lymphoid hypoplasia, and deposition of a fine network of reticulin fibers. Splenomegaly, an increase in splenic megakaryocytes, and extramedullary hematopoiesis accompany the hematologic changes in the peripheral blood and marrow to complete a spectrum of pathologic features similar to those reported in patients with myelofibrosis and megakaryocyte hyperplasia. However, all the PEG-rHuMGDF-initiated hematopathology including the increase in marrow reticulin is completely and rapidly reversible upon the cessation of administration of PEG-rHuMGDF. Thus, transient hyperplastic proliferation of megakaryocytes does not cause irreversible tissue injury. Furthermore, PEG-rHuMGDF completely ameliorates carboplatin-induced thrombocytopenia at a low-dose that does not cause the hematopathology associated with myelofibrosis. 相似文献
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Kelsey E Huntington Anna Louie Lanlan Zhou Attila A Seyhan Aaron WP Maxwell Wafik S El-Deiry 《American journal of cancer research》2022,12(1):138
Tumor cells upregulate myriad proteins that are important for pH regulation, resulting in the acidification of the extracellular tumor microenvironment (TME). Abnormal pH is known to dampen immune function, resulting in a worsened anti-tumor immune response. Understanding how extrinsic alterations in pH modulate the interactions between immune cells and tumors cells will help elucidate opportunities for new therapeutic approaches. We observed that pH impacts the function of immune cells, both natural killer (NK) and T cells, which is relevant in the context of a highly acidic TME. Decreased NK and T cell activity was correlated with decreasing pH in a co-culture immune cell-mediated tumor cell-killing assay. The addition of pH-modulating drugs cariporide, lansoprazole, and acetazolamide to the co-culture assay was able to partially mitigate this dampened immune cell function. Treatment of colorectal cancer (CRC) cells with NHE1 inhibitor cariporide increased CRC cell-secreted cytokines involved in immune cell recruitment and activation and decreased cytokines involved in epithelial-mesenchymal transition (EMT). Cariporide treatment also decreased CRC cell shed TRAIL-R2, TRAIL-R3, and PD-L1 which is relevant in the context of immunotherapy. These experiments can help inform future investigations into how the pH of the tumor microenvironment may be extrinsically modulated to improve anti-tumor immune response in solid tumors such as colorectal cancer. 相似文献
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Intracytoplasmic Sperm Injection Increases Embryo Fragmentation Without Affecting Clinical Outcome 总被引:1,自引:1,他引:0
Frattarelli JL Leondires MP Miller BT Segars JH 《Journal of assisted reproduction and genetics》2000,17(4):207-212
Purpose: To examine the effect of intracytoplasmic sperminjection (ICSI) on embryo fragmentation and implantationrates in those embryos chosen for transfer compared toconventional in vitro fertilization (IVF).
Methods: We compared 253 infertility patients (71 ICSI and182 IVF) with respect to age, semen analysis, number ofembryos transferred, embryo fragmentation, implantationrate, and pregnancy rate. Embryo fragmentation wasdetermined by one observer at the same laboratory over the entirestudy period.
Results: A statistically significant difference was observedin mean embryo grade between IVF (2.2 ± 0.84) and ICSI(2.5 ± 0.77), P = 0.01. Additionally, the IVF patients hadsignificantly more nonfragmented (grade I) embryoscompared to the ICSI group, P < 0.01.
Conclusions: These data suggest that ICSI, irrespective ofsemen parameters, may increase embryo fragmentation andproduce fewer nonfragmented grade I embryos while maintaining implantation and pregnancy rates similar toconventional IVF. 相似文献
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Masclee AA; Hopman WP; Corstens FH; Rosenbusch G; Jansen JB; Lamers CB 《Radiology》1989,173(2):407-410
Both ultrasonography (US) and cholescintigraphy are used to study gallbladder dynamics. The present study was undertaken to determine whether the two methods provide the same or different information relating to gallbladder emptying. Emptying was simultaneously studied with both methods during infusion of graded physiologic doses of cholecystokinin (CCK) in six healthy subjects. Infusion of stepwise increasing doses of CCK, ranging from 0.03 to 0.5 Ivy dog units per kilogram of body weight per hour (IDU/kg.h), induced significant dose-related increases in plasma CCK, decreases in gallbladder volume assessed with US, and gallbladder emptying assessed with cholescintigraphy. The threshold dose for inducing significant gallbladder emptying was 0.13 IDU/kg.h, as determined with both techniques, indicating similar detection limits. There was a highly significant correlation between decreases in gallbladder volume and decreases in radioactive counts over the gallbladder region, with a tendency toward greater gallbladder responses at sonography during the early phase of gallbladder contraction and toward greater responses at cholescintigraphy during the later phase of gallbladder contraction. It is concluded that these methods can be used interchangeably for the quantitation of gallbladder emptying. 相似文献
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