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排序方式: 共有164条查询结果,搜索用时 31 毫秒
31.
Epidepride的合成   总被引:2,自引:0,他引:2  
目的:研究Epidepride的化学合成方法。方法:以3-甲氧基水杨酸为原料,经五步反应合成Epidepride。结果:得到的样品经IR,NMR,MS等波谱分析及元素分析证明该化合物为Epidepride,总收率为43%。结论:该合成方法简单,收率稳定,反应条件温和。  相似文献   
32.
Numerous formulas have been developed to estimate renal function from biochemical, demographic and anthropometric data. Here we compared renal function derived from 12 published prediction equations with glomerular filtration rate (GFR) measurement by plasma iohexol clearance as reference method in a group of 81 renal transplant recipients enrolled in the Mycophenolate Mofetil Steroid Sparing (MY.S.S.) trial. Iohexol clearances and prediction equations were carried out in all patients at months 6, 9 and 21 after surgery. All equations showed a tendency toward GFR over-estimation: Walser and MDRD equations gave the best performance, however not more than 45% of estimated values were within +/-10% error. These formulas showed also the lowest bias and the highest precision: 0.5 and 9.2 mL/min/1.73 m2 (Walser), 2.7 and 10.4 mL/min/1.73 m2 (MDRD) in predicting GFR. A significantly higher rate of GFR decline ranging from -5.0 mL/min/1.73 m2/year (Walser) to -7.4 mL/min/1.73 m2/year (Davis-Chandler) was estimated by all the equations as compared with iohexol clearance (-3.0 mL/min/1.73 m2/year). The 12 prediction equations do not allow a rigorous assessment of renal function in kidney transplant recipients. In clinical trials of kidney transplantation, graft function should be preferably monitored using a reference method of GFR measurement, such as iohexol plasma clearance.  相似文献   
33.
白慧艳  刘敏言  田瑞琴 《医学争鸣》1999,20(11):931-931
0 引言 眩晕是一种旋转错觉.压力性眩晕又称气压变化性眩晕,是一种较少见的飞行错觉.在我军,有关飞行员压力性眩晕的病例尚未见报道.1 病例报告 男,36岁,某航校歼击机飞行教员,飞行时间1500h.在飞行中曾先后两次发生滚转错觉.第1次,1997-0...  相似文献   
34.
Scott  MA; Apperley  JF; Jestice  HK; Bloxham  DM; Marcus  RE; Gordon  MY 《Blood》1995,86(12):4468-4473
The use of peripheral blood progenitor cells (PBPC) to reconstitute hematopoiesis after high-dose chemoradiotherapy is now commonplace in the treatment of malignancies. Attempts to characterize these cells have concentrated primarily on their phenotype and their content of clonogenic colony-forming cells (CFC). We have used a plastic-adherent delta (P delta) assay system to evaluate the quantity and quality of more primitive cells in addition to the conventional measurements of CFC and CD34-positive cells. The leukapheresis products from 20 patients mobilized using cyclophosphamide (Cy) and granulocyte colony- stimulating factor (G-CSF) were examined for progenitor cell content. The mean number of mononuclear cells (MNC), colony-forming units- granulocyte/macrophage (CFU-GM), and CD34-positive cells from two leukaphereses per patients were 7.9 x 10(8)/kg, 47.3 x 10(4)/kg, and 10.5 x 10(6)/kg, respectively. The mean number of P delta progenitors was 9.3 x 10(4)/kg. Limiting dilution analyses showed the frequency of P delta progenitors in PBPC to be between 1 and 5.3 per 10(5) MNC and that each P delta progenitor has the proliferative capability to generate an overall mean of 4.5 CFU-GM. Of the 20 patients, 16 underwent autografting with PBPC alone. Fifteen patients engrafted neutrophils and platelets within 16 days. One patient had delayed engraftment associated with inadequate etoposide clearance. Statistical analysis showed a strong correlation between numbers of CFU-GM and CD34 positivity. The numbers of plastic-adherent P delta progenitor cells did not correlate with CFU-GM or CD34-positive cells. We conclude that the plastic-adherent P delta progenitor cell assay is capable of measuring primitive hematopoietic cells and that it may be useful for the investigation of primitive progenitors in PBPC harvests.  相似文献   
35.
Lee  MY; Fevold  KL; Dorshkind  K; Fukunaga  R; Nagata  S; Rosse  C 《Blood》1993,82(7):2062-2068
Transplantation of a granulocytosis-inducing murine CE mammary carcinoma into mice suppresses primary B lymphopoiesis in the marrow. The mechanisms of this tumor-induced B-cell suppression were investigated using Whitlock-Witte-type lymphoid cultures. When seeded with normal marrow progenitors, stromal cells of tumor-bearing mice supported the production of B220+ cells as well as did either stomal cells derived from control mice or the stromal cell line S17. Cultured over normal stroma, marrow cells of tumor-bearing mice depleted of adherent cells and B220+ cells generated B220+ cells as effectively as a similar cell population from control mice. However, interleukin-7- responsive progenitors, were completely depleted from the marrow of tumor-bearing mice. When conditioned medium (CM) of cloned CE tumor cells known to produce granulocyte colony-stimulating factor (G-CSF) and macrophage-CSF, or recombinant murine G-CSF was added to the cultures established with S17 cells, B220+ cell production was significantly diminished. Antiserum to murine G-CSF blocked these effects. These in vitro observations were corroborated by the elimination of marrow B220+ cells in mice injected with G-CSF. These in vitro and in vivo studies suggest that G-CSF plays an inhibitory role in primary B lymphopoiesis by blocking stromal cell-mediated differentiation of early B-cell progenitors into phenotypically recognizable B220+ pre-B cells.  相似文献   
36.
Diet‐induced weight loss has been suggested to be harmful to bone health. We conducted a systematic review and meta‐analysis (using a random‐effects model) to quantify the effect of diet‐induced weight loss on bone. We included 41 publications involving overweight or obese but otherwise healthy adults who followed a dietary weight‐loss intervention. The primary outcomes examined were changes from baseline in total hip, lumbar spine, and total body bone mineral density (BMD), as assessed by dual‐energy X‐ray absorptiometry (DXA). Secondary outcomes were markers of bone turnover. Diet‐induced weight loss was associated with significant decreases of 0.010 to 0.015 g/cm2 in total hip BMD for interventions of 6, 12, or 24 (but not 3) months' duration (95% confidence intervals [CIs], –0.014 to –0.005, –0.021 to –0.008, and –0.024 to –0.000 g/cm2, at 6, 12, and 24 months, respectively). There was, however, no statistically significant effect of diet‐induced weight loss on lumbar spine or whole‐body BMD for interventions of 3 to 24 months' duration, except for a significant decrease in total body BMD (–0.011 g/cm2; 95% CI, –0.018 to –0.003 g/cm2) after 6 months. Although no statistically significant changes occurred in serum concentrations of N‐terminal propeptide of type I procollagen (P1NP), interventions of 2 or 3 months in duration (but not of 6, 12, or 24 months' duration) induced significant increases in serum concentrations of osteocalcin (0.26 nmol/L; 95% CI, 0.13 to 0.39 nmol/L), C‐terminal telopeptide of type I collagen (CTX) (4.72 nmol/L; 95% CI, 2.12 to 7.30 nmol/L) or N‐terminal telopeptide of type I collagen (NTX) (3.70 nmol/L; 95% CI, 0.90 to 6.50 nmol/L bone collagen equivalents [BCEs]), indicating an early effect of diet‐induced weight loss to promote bone breakdown. These data show that in overweight and obese individuals, a single diet‐induced weight‐loss intervention induces a small decrease in total hip BMD, but not lumbar spine BMD. This decrease is small in comparison to known metabolic benefits of losing excess weight. © 2015 American Society for Bone and Mineral Research  相似文献   
37.
38.
Fluorescence in situ hybridization (FISH) probe for the identification of the Philadelphia (Ph) translocation [t(9;22) (q34;q11)] in chronic myelogenous leukemia cells was developed by inter-Alu-polymerase chain reaction of DNA from an interspecific somatic cell hybrid containing approximately 5 Mb of human DNA covering the ABL gene region on human chromosome 9q34. This probe was large enough to be effective in identifying the genomic domains yet small enough to resolve them in more than 90% of bone marrow interphase cells. Combination of the probe with a cosmid contig probe for the BCR region of chromosome 22 in two- color FISH reduced the frequency of false-positive identification of the Ph chromosome to less than 1%. The procedure allows detection of as few as 1% Ph+ cells independent of the cycling status or BCR/ABL expression level of cells, and the quantitation of non-Ph chromosome- containing interphase nuclei in the marrow of patients judged 100% Ph+ by standard cytogenetics.  相似文献   
39.
40.
Background  The relationship between elevated basal FSH and embryo quality remains a topic of heated discussion among practitioners of ART. Some authors suggest a negative effect of raised FSH on the quality of embryos and therefore on IVF treatment outcome. We postulate that women with elevated FSH who respond well to ovarian stimulation and have embryos to transfer, have the same chance of conceiving like women of a similar age with normal FSH. To test this hypothesis, we studied women with elevated basal FSH who made enough embryos to qualify for blastocyst culture and day 5 embryo transfer. Methods  Analysis of data collected prospectively, on women age 25–43 years, who underwent IVF between January 2005 and December 2006. The women were divided into: those with high FSH (≥10 IU/L) and women with normal FSH (<10 IU/L). We analysed data to show treatment outcome in the two groups, following embryo transfer on day 3 and after transfer on day 5. Outcome measures include number of oocytes retrieved, number of embryos available, implantation rate, pregnancy and live birth rate. Results  Among the 1,858 women who under-went a day 3 transfer, 1,368 had basal FSH ≤ 10 IU/L, and in 492 basal FSH was above 10 IU/L. The average number of oocytes retrieved was lower among women with elevated FSH (10.12 ± 5.6 Vs 6.16 ± 3.9). Women with a normal FSH, had a higher pregnant and live birth rate than those with elevated FSH (43.3% vs 27.9% p = 0.021) and (30.8% vs 17.6% p = 0.028) respectively. 398 women made enough embryos to qualify for extended embryo culture to blastocysts. Of these 366 had an FSH ≤ 10 IU/L and 32 had FSH > 10 IU/L. In this group, there was no significant difference in the pregnancy and live birth rates between women with elevated and those with normal FSH, (67.2% vs 65.6%) and (51.9% vs 43.8%) respectively. In this selected group of women where quantity is not an issue, the quality of embryos was same irrespective of whether the basal FSH was low or high. Conclusion  Women with elevated basal FSH who respond well to stimulation and generate a good number of oocytes / embryos have a chance of becoming pregnant and having a live birth similar to that of women of their age. Women should therefore not be denied the benefits of IVF based solely on the basal FSH level as a subset may respond well and therefore have a good chance of taking home a baby.  相似文献   
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