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101.
OBJECTIVE: The purpose of this study was to use proton magnetic resonance spectroscopy (MRS) as a metabolic assay to describe biochemical changes during the evolution of neuronal injury in infants after shaken baby syndrome (SBS), that explain the disparity between apparent physical injury and the neurological deficit after SBS. METHODOLOGY: Three infants [6 months (A), 5 weeks (B), 7 months (C)] with SBS were examined repeatedly using localized quantitative proton MRS. Examinations were performed on days 7 and 13 (A), on days 1, 3, 5, and 12 (B), and on days 7 and 19 (C) posttrauma. Long-term follow-up examinations were performed 5 months posttrauma (A) and 4.6 months posttrauma (B). Data were compared to control data from 52 neurologically normal infants presented in a previous study. RESULTS: Spectra from parietal white matter obtained at approximately the same time after injury (5 to 7 days) showed markedly different patterns of abnormality. Infant A shows near normal levels of the neuronal marker N-acetyl aspartate, creatine, and phosphocreatine, although infant C shows absent N-acetyl aspartate, almost absent creatine and phosphocreatine, and a great excess of lactate/lipid and lipid. Analysis of the time course in infant B appears to connect these variations as markers of the severity of head injury suffered in the abuse, indicating a progression of biochemical abnormality. The principal cerebral metabolites detected by MRS that remain normal up to 24 hours fall precipitately to approximately 40% of normal within 5 to 12 days, with lactate/lipid and lipid levels more than doubling concentration between days 5 and 12. CONCLUSIONS: A strong impression is gained of MRS as a prognostic marker because infant A recovered although infants B and C remained in a state consistent with compromised neurological capacity. Loss of integrity of the proton MR spectrum appears to signal irreversible neurological damage and occurs at a time when clinical and neurological status gives no indication of long-term outcome. These results suggest the value of sequential MRS in the management of SBS. 相似文献
102.
Liang Wang MD Chao Li BD Kaifei Han BD Yongqin Chen BD Lei Qi MD Xinyu Liu MD 《Orthopaedic Surgery》2023,15(3):695-703
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Detecting fetomaternal hemorrhage: a comparison of five methods 总被引:3,自引:0,他引:3
KM Bayliss ; BD Kueck ; ST Johnson ; JT Fueger ; PW McFadden ; D Mikulski ; JL Gottschall 《Transfusion》1991,31(4):303-307
Appropriate postpartum administration of Rh immune globulin relies on sensitive detection and accurate quantitation of fetomaternal hemorrhage (FMH). Recently, the microscopic Du test (micro Du) enhanced with polyethylene glycol (PEG Du) and flow cytometry (FC) have been advocated for this purpose. Three qualitative methods (micro Du, rosette test, and PEG Du) and two quantitative methods (acid elution and FC) for assessing FMH were evaluated with particular attention given to PEG Du and FC. In vitro studies comprised 10 series of dilutions of D+ cord cells in D- adult cells to yield D+ cell concentrations of 0.06, 0.12, 0.25, 0.50, 0.75, 1.0, and 2.0 percent. Additionally, 26 postpartum samples were tested. Of the qualitative techniques, the micro Du test was the least sensitive with 20 percent false-negative results occurring at 0.5 percent fetal cells. The PEG Du test was only slightly more sensitive and offered no clinical advantage. The rosette test was the most sensitive, consistently detecting fetal cells at concentrations of 0.25 percent or greater. FC and acid elution showed similar results, with good correlation obtained between measured and expected quantities of fetal cells (r = 0.99 and 0.96, respectively). One of 26 postpartum samples was positive by all screening techniques; acid elution and FC detected 0.3-percent concentrations of fetal cells and 0.17-percent concentrations of D+ cells, respectively. Although acid elution is a more commonly used method for quantitating FMH, FC offers an acceptable alternative that is capable of analyzing large numbers of cells with objectivity and reproducibility. 相似文献
107.
辽西地区农村汉族青少年体型发育规律的Heath-Carter体型法分析 总被引:1,自引:0,他引:1
目的:分析辽西地区农村汉族青少年的体型发育规律和特点,为体质人类学补充必要的数据。对象:按整群分层抽样法,抽取2001-07/2003-09辽西地区锦州、盘锦、葫芦岛、义县和绥中的农村13所中小学7~19岁经学校正常体质检查证明身体健康的汉族学生为调查对象,按性别分两大组,每大组按年龄分12小组,7~18岁每岁为1个年龄组,18~19岁为1个年龄组,每小组44~82人,共分24组,搜集完整资料1280名(男666名,女614名)。采用Heath-Carter体型法,每项指标测量2次,取平均值,10项指标由专人负责,测试数据按年龄和性别在微机中建立数据库,依次计算出各年龄组的内因子、中因子和外因子,体型图上的X,Y坐标值,身高/体质量1/3,样本中平均体型点到所有体型点空间距离的均数,三维空间中两个体型点间的差异,体脂百分比和各类体型分布频数。结果:参加调查1280名,均进入结果分析。①7~17岁青少年身高、体质量随年龄的增加而增长。平均身高、体质量男生大于女生。身高/体质量1/3指数除7、8、10、12和13岁外,各年龄组男生>女生,平均值男生>女生。体脂含量除8岁外,其他年龄组女生>男生,平均值女生>男生。②男生的体型均值3.6-2.5-3.7,属外胚层-内胚层均衡体型,女生平均体型值为4.3-2.2-3.3,属于偏外胚层的内胚层体型。体型频数的变化提示辽西农村汉族男生体型分布在内胚层和外胚层的体型较多,女生分布较集中,主要在内胚层体型。③内因子男生在3.0~4.0,女生在3.5~5.2,各年龄组女生>男生;中因子男生在1.6~3.9,女生在0.8~3.4,除7、11和17岁女生>男生外,其他年龄组男生>女生或男女相等,平均值男生>女生。外因子男生在3.0~5.0,女生在3.0~4.1,7、8、10、12、13岁女生>男生,11、14、15、16、17、18岁男生>女生。因此,女生的内因子占优势,皮下脂肪更发达,体态丰满,男生中因子占优势,骨骼粗壮,肌肉发达,随着年龄的增长,男生的身体相对瘦高程度增长,身材修长。④男女各年龄组间体型比较,7,8,9,10,11,12,13,14,15,16,17,18~19岁三维空间中两个体型点间的差异值分别为0.45,0.67,1.03,0.56,0.76,0.30,0.93,2.60,1.86,1.37,1.21,1.47,8~11岁年龄组男女间体型差异有显著性(t=2.66,2.75,2.95,3.58,P<0.05)。⑤与城市青少年相比,农村青少年身高低5~6cm(男女分别为u=6.24,5.90,P<0.01),体质量低3~6kg(男女分别为u=6.93,4.60,P<0.01)。结论:辽西地区农村男生较女生骨骼粗壮,肌肉发达,女生的皮下脂肪更发达,体态丰满,随着年龄的增长,男生的身体相对瘦高,身材修长。与城市青少年相比,农村青少年仍矮瘦,与国外资料和国内少数民族相比,辽西地区农村汉族青少年骨骼肌肉欠发达,身材修长。 相似文献
108.
Effects of in vitro purging with 4-hydroperoxycyclophosphamide on the hematopoietic and microenvironmental elements of human bone marrow 总被引:1,自引:0,他引:1
Siena S; Castro-Malaspina H; Gulati SC; Lu L; Colvin MO; Clarkson BD; O'Reilly RJ; Moore MA 《Blood》1985,65(3):655-662
We describe the effects of 4-hydroperoxycyclophosphamide (4-HC) on the hematopoietic and stromal elements of human bone marrow. Marrow cells were exposed to 4-HC and then assayed for mixed (CFU-Mix), erythroid (BFU-E), granulomonocytic (CFU-GM), and marrow fibroblast (CFU-F) colony-forming cells and studied in the long-term marrow culture (LTMC) system. The inhibition of colony formation by 4-HC was dose and cell- concentration dependent. The cell most sensitive to 4-HC was CFU-Mix (ID50 31 mumol/L) followed by BFU-E (ID50 41 mumol/L), CFU-GM (ID50 89 mumol/L), and CFU-F (ID50 235 mumol/L). In LTMC, a dose-related inhibition of CFU-GM production was noted. Marrows treated with 300 mumol/L 4-HC were completely depleted of CFU-GM but were able to generate these progenitors in LTMC. Marrow stromal progenitors giving rise to stromal layers in LTMC, although less sensitive to 4-HC cytotoxicity, were damaged by 4-HC also in a dose-related manner. Marrows treated with 4-HC up to 300 mumol/L, gave rise to stromal layers composed of fibroblasts, endothelial cells, adipocytes, and macrophages. Cocultivation experiments with freshly isolated autologous hematopoietic cells showed that stromal layers derived from 4-HC- treated marrows were capable of sustaining the long-term production of CFU-GM as well as controls. In conclusion: (1) Hematopoietic progenitors cells, CFU-Mix, BFU-E, and CFU-GM, are highly sensitive to 4-HC, whereas marrow stromal progenitor cells are relatively resistant. (2) Marrows treated with 300 mumol/L 4-HC that are depleted of CFU-Mix, BFU-E, and CFU-GM can generate CFU-GM in LTMC, suggesting that most primitive hematopoietic stem cells (not represented by CFU-Mix) are spared by 4-HC up to this dose. (3) Consequently, the above colony assays are not suitable tools for predicting pluripotent stem cell survival after 4-HC treatment in vitro. 相似文献
109.
Hypermethylation of the 5' region of the calcitonin gene is a property of human lymphoid and acute myeloid malignancies 总被引:11,自引:0,他引:11
Baylin SB; Fearon ER; Vogelstein B; de Bustros A; Sharkis SJ; Burke PJ; Staal SP; Nelkin BD 《Blood》1987,70(2):412-417
An abnormal increase in numbers of CCGG sites methylated in the 5' region of the human calcitonin (CT) gene occurred in tumor cell DNA samples from 90% (17 of 19) of patients with non-Hodgkin's T and B cell lymphoid neoplasms and in 95% (21 of 22) of tumor cell DNA samples from patients with acute nonlymphocytic leukemia (ANLL). The changes were not seen in patients with chronic myelogenous leukemia (0 of 9). The abnormal methylation patterns appear to be a property only of transformed or malignant cells since they were not found in DNA from nonneoplastic adult tissues including sperm, early myeloid progenitor cells, benign lymphoid hyperplasia, peripheral lymphocytes stimulated to divide, or early myeloid progenitor cells (obtained by immunoaffinity using anti-My-10 antibody), but they did appear after Epstein-Barr virus transformation of lymphocytes. Moreover, during the course of therapy in patients with ANLL, the hypermethylation pattern reflects the presence of the leukemic clone even in normal-appearing granulocytes derived from this clone. The increased methylation of the CT gene may then provide an important molecular marker for biologic events in human cell transformation or tumor progression and may prove clinically useful in monitoring patients with lymphoid and acute myelogenous neoplasms. 相似文献
110.