全文获取类型
收费全文 | 2106篇 |
免费 | 139篇 |
国内免费 | 45篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 96篇 |
妇产科学 | 26篇 |
基础医学 | 163篇 |
口腔科学 | 41篇 |
临床医学 | 289篇 |
内科学 | 336篇 |
皮肤病学 | 44篇 |
神经病学 | 58篇 |
特种医学 | 290篇 |
外科学 | 292篇 |
综合类 | 212篇 |
预防医学 | 172篇 |
眼科学 | 16篇 |
药学 | 118篇 |
2篇 | |
中国医学 | 32篇 |
肿瘤学 | 87篇 |
出版年
2022年 | 30篇 |
2021年 | 28篇 |
2020年 | 27篇 |
2018年 | 19篇 |
2017年 | 21篇 |
2016年 | 18篇 |
2015年 | 33篇 |
2014年 | 48篇 |
2013年 | 76篇 |
2012年 | 78篇 |
2011年 | 89篇 |
2010年 | 96篇 |
2009年 | 104篇 |
2008年 | 70篇 |
2007年 | 81篇 |
2006年 | 83篇 |
2005年 | 56篇 |
2004年 | 49篇 |
2003年 | 51篇 |
2002年 | 53篇 |
2001年 | 41篇 |
2000年 | 30篇 |
1999年 | 32篇 |
1998年 | 83篇 |
1997年 | 75篇 |
1996年 | 72篇 |
1995年 | 69篇 |
1994年 | 43篇 |
1993年 | 50篇 |
1992年 | 17篇 |
1991年 | 25篇 |
1990年 | 15篇 |
1989年 | 37篇 |
1988年 | 43篇 |
1987年 | 41篇 |
1986年 | 30篇 |
1985年 | 37篇 |
1984年 | 21篇 |
1983年 | 25篇 |
1982年 | 16篇 |
1980年 | 17篇 |
1977年 | 16篇 |
1963年 | 17篇 |
1960年 | 14篇 |
1959年 | 22篇 |
1958年 | 29篇 |
1957年 | 19篇 |
1956年 | 30篇 |
1955年 | 42篇 |
1954年 | 35篇 |
排序方式: 共有2290条查询结果,搜索用时 343 毫秒
81.
自体外周血造血干细胞和自体骨髓移植治疗急性髓性白血病的临床疗效比较研究 总被引:4,自引:0,他引:4
目的:比较自体外周血干细胞移植(APBSCT)与自体骨髓移植治疗CR1期急性髓性白血病(AML)的临床疗效。方法:用APBSCT治疗AML患者27例,用非净化自体骨髓移植(ABMT)治疗AML患者13例,用净化自体骨髓移植(PABMT)治疗AML患者25例。结果:(1)APBSCT组造血重建校其他两组显著加快;(2)APBSCT组的3年无病生存率(DFS)和复发率(RR)分别为51.%和42.2%,与ABMT组的46.2%、46.7%相当,但与净化ABMT组的72.9%、23.7%相比差异有显著性意义。(3)三组的移植相关死亡率(TRM)差异无显著性意义,死亡的主要原因为感染和内脏出血。结论:APBSCT治疗CR1期AML,其造血重建显著快于ABMT,其疗效与ABMT相当,而显著低于PABMT。 相似文献
82.
Shimazaki C; Wisniewski D; Scheinberg DA; Atzpodien J; Strife A; Gulati S; Fried J; Wisniewolski R; Wang CY; Clarkson BD 《Blood》1988,72(4):1248-1254
The efficacy of immunomagnetic beads to purge human myeloma cells from bone marrow ex vivo was evaluated. The optimal conditions for purging were studied first by using three myeloma cell lines: RPMI-8226, SKO- 007, and SKMM-2. Myeloma cells labeled with the vital fluorescent dye Hoechst 33342 were admixed with normal bone marrow cells, and two monoclonal antibodies reactive with the myeloma cells (PCA-1 and BL-3) were added alone or in combination with the cells. Magnetic beads coated with goat antimouse immunoglobulin G were then added, and the tumor cells to which beads were attached were separated from the mixture with a magnet. The efficacy of tumor cell removal was dependent on the bead-to-tumor ratio; a ratio of more than 500 was optimal in the presence of excess normal marrow cells. The combination of monoclonal antibodies PCA-1 and BL-3 increased the tumor cell removal as compared with either antibody alone. Two cycles of treatment were more effective than one cycle was. Under optimal conditions, 2.3 to 4 logs of tumor cells could be removed from the mixture containing 10% myeloma cells without a significant loss of normal hematopoietic progenitors as measured by CFU-GM, CFU-GEM, and BFU-E. When the efficacy of this procedure was tested on fresh bone marrow from patients with multiple myeloma (MM) by using the combination of PCA-1, BL-3, and J-5, 1.6 to 2.5 logs of tumor cells could be removed by one cycle of treatment, even from marrows containing less than 10% myeloma cells. These observations support the use of monoclonal antibody combinations and immunobeads as a reliable and nontoxic method to eliminate contaminating myeloma cells ex vivo in preparation for autologous bone marrow transplantation in patients with MM. 相似文献
83.
Oxidative metabolism of the human eosinophil 总被引:14,自引:1,他引:14
We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst. 相似文献
84.
Chronic granulocytic leukaemia (CGL) cells which contained a high concentration of unsaturated folate binding protein were incubated in suspension culture for a period of 5 h. Cell samples were periodically assayed for binder and these demonstrated active synthesis which was inhibited by puromycin, cyclo heximide, N-ethylmaleimide, and by incubation at 4 degrees C, but not by actinomycin D. Folate binding activity could also be demonstrated in the culture medium and this increased with the duration of incubation. This release of binder was inhibited by culturing the cells at 4 degrees C and by the addition of N-ethylmaleimide, but not by actinomycin D, puromycin, or cycloheximide. When the pre- and post-culture cell lysates were saturated with tritiated folic acid ([3H]PteGlu) and subjected to chromatography on DEAE-agrarose, approximately half of the bound folate eluted with 0.001 M phosphate buffer at pH 6.0 and the other half eluted with 0.2 M buffer at pH 7.2. The culture medium and plasma from this patient with CGL was well as serum from two normal subjects saturated with [3H]PteGlu and similarly chromatographed contained primarily the acidic binder and much less of the binder eluting with the low molarity buffer. Since a folate binding protein immunochemically similar to the binder in CGL cells has been identified in the serum of non-leukaemic subjects, these experiments suggest that the source of circulating folate binding protein may be the immature granulocyte. 相似文献
85.
6q deletions define distinct clinico-pathologic subsets of non- Hodgkin's lymphoma 总被引:11,自引:1,他引:11
Offit K; Parsa NZ; Gaidano G; Filippa DA; Louie D; Pan D; Jhanwar SC; Dalla- Favera R; Chaganti RS 《Blood》1993,82(7):2157-2162
Commonly observed in lymphoid neoplasms, deletions of 6q have been correlated with histologic and clinical subsets of non-Hodgkin's lymphoma (NHL). Our recent analysis of loss of heterozygosity of 6q loci in NHL showed two regions of minimal molecular deletion (RMD), an RMD1 at 6q25-27 and an RMD2 at 6q21-23. To establish correlations between these RMDs and regions of minimal cytogenetic deletions (RCDs) on 6q, and to define associations between RCDs and clinico-pathologic features, we have analyzed chromosome 6 abnormalities in 459 consecutively ascertained, karyotypically abnormal cases of NHL. Among these, 126 (27.5%) cases had structural abnormalities of chromosome 6, of which 94 were deletions. Analysis of these deletions identified three RCDs. An RCD1 encompassing 6q25-27 was seen in 45 intermediate- grade NHL. An RCD2 at 6q21 was observed in 11 high-grade NHL, 9 of which were of the immunoblastic subtype. An RCD3 at 6q23 was noted in 18 low-grade NHL lacking a t(14;18) translocation. Of these 18 cases, 12 were small lymphocytic NHL and, in 2 of these, del(6q) was the sole karyotypic abnormality. In 20 cases of low-grade NHL with t(14;18), the deletions spanned both RCD1 and RCD3. These data suggested the presence of at least 3 tumor suppressor genes on 6q within RCD1, RCD2, and RCD3; they also showed associations between RCDs in 6q and subsets of NHL, including a specific association between a group of well-differentiated lymphoid neoplasms and RCD3. The apparent heterogeneity of breakpoints when all NHLs are considered together explains the inability of previous studies to reliably establish correlations between recurring 6q deletions and histologic and clinical features of NHL. 相似文献
86.
87.
Prevalence of Candida spp., xerostomia,and hyposalivation in oral lichen planus – A controlled study
Objective
To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non‐OLP group), and subjects without oral mucosal lesions (control group).Material and methods
Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non‐OLP lesions (28 patients), and healthy subjects (32 subjects).Results
There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (P = 0.03) and non‐OLP (P = 0.02) groups. Low SFR was not a factor for colonization by Candida spp.Conclusions
Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme. 相似文献88.
目的研究B超引导下臂丛神经阻滞麻醉的临床效果及安全性。方法将本院行上肢手术的90例患者随机分为对照组(n=48)和B超引导组(n=42)。对照组以盲探的方法行臂丛神经阻滞麻醉,B超引导组在B型超声仪引导下行臂丛神经阻滞麻醉。比较两组的麻醉效果。结果B超引导组感觉阻滞起效时间、麻醉药物使用剂量均优于对照组,但麻醉操作时间长于对照组(P<0.05)。B超引导组不同臂丛神经的感觉阻滞完善率均高于对照组,并发症总发生率低于对照组(P<0.05)。结论与盲探法相比,B超引导下行臂丛神经阻滞麻醉的麻醉操作时间虽然有所延长,然而麻醉效果佳,能够缩短感觉阻滞起效时间、减少麻醉药物用量,且安全性好。 相似文献
89.
90.
Amanda Haboush Tara Phebus Denise Tanata Ashby Helen Zaikina-Montgomery Kimberly Kindig 《Journal of community health》2011,36(1):111-120
The goal of the this study was to track and assess children’s health status in Nevada and build relationships between researchers
and school districts through the collection of mutually beneficial health data at a local level. All elementary schools in
Nevada were sent a health survey for parents of kindergarten students to complete. A total of 3,628 surveys were received
with usable height and weight needed to calculate Body Mass Index (BMI). African American and Hispanic children had significantly
higher BMI scores compared to Caucasian and Asian/Pacific Islander children, regardless of income. Children who had diabetes
or mental health concerns also had significantly higher mean BMIs compared to children without these health concerns. Overall
staff within the school districts felt that this surveillance system should be continued as data from this study provided
important information subsequently used to guide programming and when applying for grants. Our children’s welfare depends
on community collaboration to create and implement data-driven initiatives to combat childhood obesity. 相似文献