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61.
瘢痕疙瘩家系Fas基因的突变:2个家系10份标本分析 总被引:1,自引:0,他引:1
目的:观察瘢痕疙瘩家系样本中Fas基因有无突变,探讨Fas基因突变在瘢痕疙瘩形成中的意义。方法:实验于2005-01/05在上海基康公司完成。①标本来自南方医科大学南方医院整形外科2005年收集的A和B两个瘢痕疙瘩家系,所有参与观察的家系成员均签署知情同意书。②采用聚合酶链反应及基因测序技术,分别以A家系两例患者的瘢痕疙瘩组织为观察对象,以其周围正常皮肤及外周静脉血作为自身对照;其配偶的外周静脉血作为正常对照。并以B家系中两例患者的外周静脉血作为不同家系间的对照。共取10份样本,4份组织样本,6份静脉血标本。检测10份样本中Fas基因外显子1~9的基因序列。结果:①基因测序发现所检测的10个瘢痕疙瘩家系标本Fas基因的1~8外显子均未发现突变。②2份瘢痕疙瘩组织标本在第9外显子编码区的11bp,53bp两个位点上存在单个碱基的基因突变或多态性改变。结论:瘢痕疙瘩Fas基因外显子9区段的基因结构异常极有可能造成Fas蛋白的功能改变,从而导致身体局部瘢痕疙瘩的形成。 相似文献
62.
跟骨定量超声骨质测量参数与骨密度及骨组织形态计量学指标的关系 总被引:1,自引:0,他引:1
目的:分析跟骨定量超声骨质测量中各参数与骨密度及形态计量学指标的相关性。方法:选择2004-01/2005-12广州市第六人民医院和中山大学三院骨科小腿以上截肢患者38例,将其跟骨定量超声测定的超声振幅衰减平均值与健康青年人骨峰值进行比较,>-2.5 SD者为骨量正常组(12例),<-2.5 SD者为骨质疏松组(26例)。分别进行跟骨定量超声、双能X线骨密度测量仪及骨形态计量学测量,应用直线相关分析法分析跟骨定量超声测定中各参数与骨密度及骨组织形态计量学各指标的相关性。结果:38例全部进入结果分析。①骨质疏松组跟骨超声振幅衰减平均值和骨硬度指数值均小于骨量正常组(P<0.01)。②骨量正常组跟骨骨密度值显著高于骨质疏松组[(352±16),(233±14)mg/cm2,P<0.01]。③骨量正常组跟骨平均骨小梁间距或弥散度低于骨质疏松组而松质骨体积高于骨质疏松组(P<0.05)。④超声振幅衰减平均值和骨硬度指数与骨密度呈直线正相关(r=0.814,0.326,P<0.01,0.05)。⑤超声传播速度与骨小梁游离末端、平均骨小梁间距呈直线负相关(r=-0.688,-0.712,P<0.01),与小梁间连点数、松质骨体积呈直线正相关(r=0.672,0.794,P<0.01);骨硬度指数与平均骨小梁间距呈直线负相关(r=-0.358,P<0.05),与松质骨体积呈直线正相关(r=0.513,P<0.01)。结论:跟骨定量超声测量中,超声振幅衰减平均值能较好地反映骨的密度,超声传播速度能较好地反映骨的质量,而骨硬度指数能较综合地反映骨强度的改变。 相似文献
63.
目的:已有研究证实,活血化瘀中药可对抗激素的作用,对激素性股骨头缺血性坏死早期有明显的防治作用。观察桃红四物汤对激素性股骨头缺血性坏死碱性成纤维细胞生长因子表达的影响,进一步阐明活血化瘀法防治激素性股骨头缺血性坏死的机制。方法:实验于2005-04/2006-10在福建中医学院中心实验室完成。①实验材料:健康成年新西兰大白兔60只,雌雄各半,体质量1.8~2.2kg,清洁级,由福建中医学院实验动物中心购自上海市松江区松联实验动物场。桃红四物汤的组成成分为:桃仁、红花、熟地、当归、白芍、川芎。②实验方法:60只健康成年新西兰大白兔,随机分为正常组6只和实验组54只。实验组采用贺氏造模法建立股骨头缺血坏死模型,6周后处死正常组和实验组各6只,确定造模成功。将造模剩余动物随机分为中药治疗组和激素对照组,每组21只:中药治疗组以桃红四物汤7mL/kg(浓度为0.75g/mL)灌胃治疗,1次/d,激素对照组以生理盐水7mL/kg灌胃治疗,1次/d。③实验评估:于治疗后1,2,4周进行股骨头组织病理学观察,并采用放射免疫法检测血清碱性成纤维细胞生长因子含量变化。结果:纳入新西兰大白兔60只,实验过程中因心脏、脑血管梗死死亡18只,进入结果分析42只。桃红四物汤灌胃治疗1,2,4周后,中药治疗组股骨头局部空骨陷窝数明显减少,与激素对照组比较,差异有显著性意义(P<0.05),中药治疗组碱性成纤维细胞生长因子表达增强,与激素对照组相比,差异有显著性意义(P<0.01)。结论:桃红四物汤能促进激素性股骨头缺血性坏死模型兔体内碱性成纤维细胞生长因子的表达,明显减少股骨头局部空骨陷窝数,促进坏死股骨头的修复,这可能是活血化瘀法防治激素性股骨头缺血性坏死的机制之一。 相似文献
64.
Expression of bcl-xL can confer a multidrug resistance phenotype 总被引:14,自引:3,他引:14
It has been suggested that genes that regulate apoptotic cell death may play an important role in determining the sensitivity of tumor cells to chemotherapy. We have recently cloned a member of the bcl-2 family, bcl- x. To test whether bcl-XL expression affects the sensitivity of tumor cells to chemotherapy, we have created stable cell lines overexpressing bcl-XL and have tested these cells for resistance to cell death induced by metabolic inhibitors and chemotherapeutic agents. Bcl-XL expression dramatically reduces the cytotoxicity of bleomycin, cisplatin, etoposide, vincristine, hygromycin B, and mycophenolic acid for up to 4 days in culture. Bcl-XL does not prevent cells from undergoing cell cycle arrest in response to these drugs, but rather prevents treated cells from undergoing apoptosis. Cell-cycle analysis on cells treated with the chemotherapeutic agents bleomycin, cisplatin, etoposide, and vincristine, show that the drugs cause growth arrest in different positions within the cell cycle. Bcl-XL expressing cells treated with chemotherapeutic drugs retain their proliferative ability after the drugs are removed. Interestingly, vincristine-treated cells expressing bcl-XL become polyploid after drug removal. These data show that bcl-XL protects cells from a wide variety of apoptotic stimuli, acts in multiple positions within the cell cycle, and confers a multidrug resistance phenotype. The ability of bcl-XL to prevent apoptotic cell death in response to chemotherapy-induced DNA damage and cell-cycle arrest may contribute to the accumulation of chromosomal aberrations within tumors. The expression of bcl-XL in tumor cells is likely to be an important indicator of chemotherapeutic efficacy. 相似文献
65.
In vitro characterization of the human recombinant soluble granulocyte- macrophage colony-stimulating factor receptor 总被引:1,自引:0,他引:1
We have cloned, expressed, and partially purified a naturally occurring, truncated, soluble form of the human granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor alpha subunit to investigate its biochemical and biologic properties. The soluble receptor species lacks the transmembrane and cytoplasmic domains that are presumably removed from the intact receptor cDNA by a mechanism of alternative splicing. The resulting soluble 55- to 60-kD glycosylated receptor species binds GM-CSF with a dissociation constant (kd) of 3.8 nmol/L. The soluble GM-CSF receptor successfully competes for GM-CSF binding not only with the transmembrane-anchored GM-CSF receptor alpha subunit but also with the native oligomeric high-affinity receptor complex. In addition, in human bone marrow colony-forming assays, the soluble GM-CSF receptor species can antagonize the activity of GM-CSF. Our data suggest that the soluble GM-CSF receptor may be capable of acting in vivo as a modulator of the biologic activity of GM-CSF. 相似文献
66.
Twenty-two patients with histologically confirmed non-Hodgkin's lymphoma received treatment with a chemotherapy combination containing cyclophosphamide, mitoxantrone, vincristine and prednisone. Leukopenia, nausea and vomiting were the most common side effects. A response rate of 77% (17 of 22 patients) was documented. These results indicate that the four-drug combination including mitoxantrone has good therapeutic activity in the treatment of non-Hodgkin's lymphoma. 相似文献
67.
68.
Trabecular bone architecture in female renal allograft recipients-- assessed by computed tomography 总被引:1,自引:0,他引:1
Grotz WH; Mundinger FA; Muller CB; Rasenack J; Schulte-Monting J; Langer MF; Schollmeyer PJ 《Nephrology, dialysis, transplantation》1997,12(3):564-569
BACKGROUND: Osteopenia with decreased bone mineral density (BMD) is a
frequent finding in renal allograft recipients. Data concerning the bone
architecture in these patients do not exist, however. METHODS: We compared
the bone architecture of 33 randomly assigned women (age 49 +/- 12 years),
who had received renal allografts 5.6 +/- 5.3 years before the
investigation, with 74 women (age 50 +/- 14 years) who were admitted for
osteodensitometry. All patients underwent single-energy computed tomography
(SEQCT) and a midvertebral high-resolution tomography with
computer-assisted analysis of the trabecular vertebral body architecture.
RESULTS: Progressive alteration of bone architecture was associated with
increasing vertebral height loss of the vertebral body. Height reduction of
a vertebral body of more than 15% was associated with a significantly lower
BMD (-2.3 +/- 0.8 versus -1.1 +/- 1.1 standard deviations below normal
BMD), a lower trabecular bone area (13 +/- 8% versus 42 +/- 22%) and a
lower trabecular diameter (1.4 +/- 0.5 mm versus 2.2 +/- 0.8 mm) compared
to recipients without height reduction. In comparison to a matched group of
patients with similarly reduced BMD (1.1 +/- 1.2 versus 1.2 +/- 1.1 SD
below normal BMD), renal allograft recipients showed a lower number of
trabecular plates (5.6 +/- 3.1 versus 7.0 +/- 3.7) and a smaller
intertrabecular surface (54 +/- 116 mm versus 75 +/- 138 mm). CONCLUSIONS:
Alterations of bone architecture in renal allograft recipients were
associated with progressive vertebral height loss. Despite similar bone
mineral density, differences of bone architecture could be observed between
renal allograft recipients and patients with osteoporosis.
相似文献
69.
I A Sesterhenn R B Weiss F K Mostofi D M Stablein R G Rowland G Falkson S E Rivkind N J Vogelzang 《Journal of clinical oncology》1992,10(1):69-78
PURPOSE: The Testicular Cancer Intergroup Study (TCIS) was undertaken to evaluate the pathologic findings in early-stage testicular cancer as determined by central pathology review, to compare these findings with the interpretation by the contributing pathologists, and to make correlations with various clinical parameters and outcomes. PATIENTS AND METHODS: The prospective study of non-seminomatous germ cell testicular cancer staged surgically involved 459 eligible patients with stage I (node-negative) or stage II (node-positive) disease. Pathologic materials from both the orchiectomy and lymphadenectomy specimens were submitted to a central laboratory for evaluation. RESULTS: Central and local pathologists differed significantly in their identification of certain cellular histologies (primarily yolk sac tumors [YST]) and recognition of invasion into vascular structures. In contrast to our prior findings with local pathologic assessment, venous/lymphatic invasion as determined by central review predicted relapse in both stages. In pathologic stage I disease, the relapse rate was 19.4% (12 of 62 cases) for those with invasion versus 6.0% (10 of 168 cases) for those without invasion. In pathologic stage II disease, the respective relapse rates were 63.5% (40 of 63 cases) and 24.0% (six of 25 cases). Vascular invasion was jointly predictive with nodal stage for risk of relapse. The percentage of embryonal carcinoma (EC) in the primary tumor was predictive of nodal stage and relapse in a univariate, but not a multivariate, analysis. In a large substudy, immunohistochemical staining identified a correlation between stain intensity in YST and serum alpha-fetoprotein (AFP) levels. In a similar fashion human chorionic gonadotropin (HCG) staining reactivity occurred exclusively in patients with syncytiotrophoblasts and correlated with serum levels of beta-HCG. CONCLUSIONS: A number of tumor histology correlates with clinical parameters have been identified or confirmed. Careful pathologic scrutiny of the primary testicular tumor, especially for vascular invasion, provides important prognostic information. 相似文献
70.
D C Tormey R Gray M D Abeloff D L Roseman K W Gilchrist E J Barylak P Stott G Falkson 《Journal of clinical oncology》1992,10(12):1848-1856
PURPOSE: A randomized trial was performed in premenopausal postoperative women with ipsilateral axillary node-positive (N+) breast carcinoma and known estrogen receptor (ER) status to assess the efficacy of an Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH)-based induction regimen and 5 or more years of tamoxifen (Tam). PATIENTS AND METHODS: Patients received 12 28-day cycles of cyclophosphamide 100 mg/m2 orally days 1 to 14, methotrexate 40 mg/m2 intravenously (IV) days 1 and 8, fluorouracil 600 mg/m2 IV days 1 and 8, prednisone 40 mg/m2 orally days 1 to 14, and Tam 10 mg orally twice daily (CMFPT), or the same regimen plus halotestin 10 mg orally twice daily (CMFPTH) alternating monthly with 22-day cycles of vinblastine 4.5 mg/m2 IV day 1, Adriamycin 45 mg/m2 IV day 1, thiotepa 12 mg/m2 IV day 1, halotestin, and Tam (ALTER). Prednisone in the ALTER regimen was stopped after the second CMFPTH cycle. After 12 cycles, patients were again randomized to stop or continue Tam. After 5 years, patients on Tam were again randomized to continue or stop Tam; the results from this randomization are still coded. Among 533 analyzed induction cases, 263 received CMFPT and 270 ALTER. Among 396 analyzed maintenance cases, 201 continued Tam and 195 were observed. Pretreatment characteristics were balanced among treatments. The median follow-up times are 5.1 years for induction and 4.1 years for maintenance. RESULTS: The time to relapse (TTR) was superior for the ALTER regimen (P = .04) and for the maintenance Tam (P = .05). Overall survival comparisons between the regimens are not statistically different. A longer TTR was associated with decreasing nodal involvement, ER+ status, and increasing age. The favorable effects of decreasing nodal involvement and ER+ status carried over to survival; a progesterone receptor-positive (PgR+) status and decreasing tumor size were also associated with longer survival. Development of amenorrhea was associated with improved TTR and survival. Toxicity was similar for the two induction regimens and for the two maintenance regimens. Overall relapse patterns were similar among the induction regimens, but continuing Tam led to fewer locoregional relapses. CONCLUSION: The results suggest significant overall TTR therapeutic benefits of an Adriamycin-containing alternating induction regimen and of continuing maintenance Tam therapy for at least 5 years. 相似文献