全文获取类型
收费全文 | 410篇 |
免费 | 15篇 |
国内免费 | 13篇 |
专业分类
儿科学 | 10篇 |
妇产科学 | 5篇 |
基础医学 | 65篇 |
口腔科学 | 12篇 |
临床医学 | 47篇 |
内科学 | 89篇 |
皮肤病学 | 7篇 |
神经病学 | 19篇 |
特种医学 | 77篇 |
外科学 | 30篇 |
综合类 | 10篇 |
预防医学 | 5篇 |
眼科学 | 2篇 |
药学 | 18篇 |
中国医学 | 3篇 |
肿瘤学 | 39篇 |
出版年
2023年 | 1篇 |
2021年 | 2篇 |
2020年 | 7篇 |
2019年 | 3篇 |
2018年 | 5篇 |
2017年 | 8篇 |
2016年 | 4篇 |
2015年 | 5篇 |
2014年 | 9篇 |
2013年 | 9篇 |
2012年 | 11篇 |
2011年 | 11篇 |
2010年 | 18篇 |
2009年 | 22篇 |
2008年 | 11篇 |
2007年 | 16篇 |
2006年 | 15篇 |
2005年 | 14篇 |
2004年 | 21篇 |
2003年 | 17篇 |
2002年 | 10篇 |
2001年 | 16篇 |
2000年 | 11篇 |
1999年 | 16篇 |
1998年 | 24篇 |
1997年 | 16篇 |
1996年 | 18篇 |
1995年 | 12篇 |
1994年 | 14篇 |
1993年 | 9篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 10篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1986年 | 8篇 |
1985年 | 9篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有438条查询结果,搜索用时 15 毫秒
101.
102.
Nodular lymphocyte predominance Hodgkin's disease: a monoclonal or polyclonal B-cell disorder? 总被引:3,自引:0,他引:3
Nodular lymphocyte predominance Hodgkin's disease (NLPHD) is characterized by the presence of atypical putatively neoplastic cells (L & H cells) with a B-cell phenotype. A proportion of patients with NLPHD develop a simultaneous or subsequent large cell B lymphoma (LCL) that is thought to evolve directly from the L & H cells of NLPHD. However, the clonal nature of L & H cells remains controversial, and the relationship between NLPHD and complicating LCL has not been fully established. In an attempt to determine the clonality of L & H cells and to clarify the link between NLPHD and complicating LCL, we used polymerase chain reaction (PCR) to analyze 33 cases of NLPHD, including 15 cases with simultaneous or subsequent LCL, for clonal immunoglobulin (lg) heavy chain variable region (VH) gene rearrangements. PCR amplifications with consensus primers covering framework 2 or framework 3 to joining region were performed on paraffin-embedded tissue sections and, in 12 cases, on microdissection-enriched L & H cells. No clonal Ig rearrangements were detected. In eight of the 15 LCL, monoclonal IgVH regions were amplified, four of which were cloned and sequenced. Clone specific primers were designed based on the unique N region sequences. These allowed detection of LCL clones at a sensitivity up to 1,000 times greater than the consensus primers, as determined by dilution assays. However, no LCL clones were detected in the preceding NLPHD, including microdissection-enriched L & H cells. Our results suggest that populations of L & H cells do not carry monoclonal Ig rearrangements and provide no evidence for a clonal link between NLPHD and complicating LCL. 相似文献
103.
P H Kann T Wascher V Zackova J Moeller J Medding A Szocs M Mokan F Mrevlje M Regulski 《Experimental and clinical endocrinology & diabetes》2006,114(9):527-532
AIM: To compare the efficacy and safety of two analog insulins as starting regimens in insulin-na?ve Type 2 diabetes patients. METHODS: In this randomized, open-label parallel study, twice-daily biphasic insulin aspart 30 (30% soluble and 70% protaminated insulin aspart; BIAsp 30) plus metformin (met) was compared with once-daily insulin glargine (glarg) plus glimepiride (glim) in 255 insulin-na?ve patients (131 male; mean+/-SD age, 61.2+/-9.1 years). Mean baseline HbA (1c) (+/-SD) was 9.2+/-1.4% and 8.9+/-1.3% for BIAsp 30 plus met ( N=128) and glarg plus glim ( N=127), respectively ( P=0.0747). Primary endpoint was the difference in absolute change in HbA (1c) between groups after 26 weeks of treatment. RESULTS: HbA (1c) change was significantly greater in the BIAsp 30 plus met group than the glarg plus glim group (between-group difference: -0.5% (95% CI: -0.8; -0.2); P=0.0002). Mean prandial plasma glucose increment was significantly lower for BIAsp 30 plus met compared with glarg plus glim: 1.4+/-1.4 mmol/l vs. 2.2+/-1.8 mmol/l; P=0.0002. During the maintenance phase (weeks 6-26), one major hypoglycemic episode occurred in each group; 20.3% and 9% of patients experienced minor hypoglycemic episodes in the BIAsp 30 plus met and glarg plus glim groups, respectively ( P=0.0124). At end-of-trial, mean daily insulin doses were 0.40 U/kg BIAsp 30 and 0.39 U/kg glarg. Glarg plus glim-treated patients experienced significant weight gain of 1.5 kg (95% CI: 0.84; 2.19; P<0.0001). Weight change with BIAsp 30 plus met of +0.7 kg was not statistically significant (95% CI: -0.07; 1.42; P=0.0762). CONCLUSIONS: Starting insulin in Type 2 diabetes patients with twice-daily BIAsp 30 plus met can reduce HbA (1c) and mean prandial plasma glucose increment to a greater extent than once-daily glarg plus glim. 相似文献
104.
整合蛋白α5亚基表达与肝癌恶性表型 总被引:3,自引:0,他引:3
目的探讨整合蛋白α5亚基与原发性肝癌的关系。方法应用免疫组化技术(ABC法)和Northernblot杂交检测整合蛋白α5亚基在原发性肝癌中的表达。结果发现在79例癌与癌周组织α5阳性率分别为32.9%和81.0%,两者间差异有显著性(P<0.01)。直径≤5cm的肝癌α5阳性率高于直径>10cm的肝癌(55.6%比10.0%,P<0.01),分化较好的肝癌α5阳性率高于分化不良者(40.6%比16.0%,P<0.05),已发生明确肝内转移(包括肝内播散和门静脉癌栓形成)的肝癌α5阳性率低于未发生肝内转移者(20.6%比42.2%,P<0.05)。α5亚基表达与患者年龄、血清甲胎蛋白水平、乙型肝炎病毒感染、肝硬化有无等因素均无明显相关(P>0.05)。Northernblot杂交结果也同时显示,非侵袭性肝癌α5表达高于侵袭性肝癌。结论整合蛋白α5低表达与肝癌增大、分化程度低、侵袭转移发生等恶性表型相关,可能对这些恶性表型起负性调节作用。 相似文献
105.
Activation of factor X by both the unactivated tissue factor:factor VII complex (TF:VII) and the activated tissue factor:factor VIIa complex (TF:VIIa) has been studied in the presence of tissue factor pathway inhibitor (TFPI), antithrombin III (ATIII), and heparin. At near-plasma concentrations of TFPI, ATIII, and factor X, factor X activation that occurs in response to TF:VII is essentially abolished in the presence of heparin (0.5 micromol/L). This effect requires both inhibitors, acting on different targets: (1) ATIII, which in the presence of heparin blocks the activation of TF:VII, and (2) TFPI, which inhibits the TF:VIIa that is generated. In the absence of ATIII, TFPI alone with heparin reduces but does not abolish factor X activation. Conversely, in the absence of TFPI, ATIII + heparin reduces but does not abolish TF:VIIa generation and allows continuing activation of factor X. These results indicated that when the unactivated TF:VII complex is the initiating stimulus, heparin-dependent reduction in the rate and extent of factor X activation requires both ATIII and TFPI. In contrast, if TF:VIIa is used to initiate activation, only TFPI is involved in its regulation. 相似文献
106.
Hepatosplenic T-cell lymphoma: a distinct clinicopathologic entity of cytotoxic gamma delta T-cell origin 总被引:7,自引:0,他引:7
Cooke CB; Krenacs L; Stetler-Stevenson M; Greiner TC; Raffeld M; Kingma DW; Abruzzo L; Frantz C; Kaviani M; Jaffe ES 《Blood》1996,88(11):4265-4274
We identified eight cases of T-cell lymphoma with evidence of a gamma delta phenotype over a 13-year period. Seven of these cases conformed to a distinct clinicopathologic entity of hepatosplenic gamma delta T- cell lymphoma. Nearly all of these patients were young adult males (five of seven), with a median age at presentation of 20 years. They presented with marked hepatosplenomegaly, without lymphadenopathy or significant peripheral blood lymphocytosis. Thrombocytopenia was seen in all patients, and five of seven were mildly anemic. The clinical course was aggressive, and despite multiagent chemotherapy, the median survival duration was less than 1 year. The morphologic findings were uniform; a monomorphic population of medium-sized lymphoid cells with moderately clumped chromatin and a rim of pale cytoplasm infiltrated the sinusoids of the spleen, liver, and bone marrow. The cells had a characteristic immunophenotype: CD2+, CD3+, CD4-, CD5-, CD7+, CD16+, CD57-, CD25-, T-cell receptor (TCR)delta +, beta F1-. CD8 was positive in four of seven cases tested, and CD56 was positive in five of six. All cases expressed the cytotoxic granule-associated protein, TIA1, but perforin was detected in only one case. All cases with assessable DNA had a TCR gamma gene rearrangement, and lacked Epstein-Barr virus sequences. Isochromosome 7q was identified in two cases with cytogenetic information. The one case of cutaneous gamma delta T-cell lymphoma differed in its clinical manifestations, histologic appearance, and immunophenotype. We conclude that hepatosplenic gamma delta T-cell lymphoma is a distinct clinicopathologic entity derived from cytotoxic gamma delta T cells, and should be distinguished from other lymphomas of T-cell and natural-killer cell (NK)-like T-cell derivation. 相似文献
107.
Jansen PM; van der Pouw Kraan TC; de Jong IW; van Mierlo G; Wijdenes J; Chang AA; Aarden LA; Taylor FB Jr.; Hack CE 《Blood》1996,87(12):5144-5151
Interleukin (IL)-12 is thought to be a key factor for the induction of interferon gamma (IFN-gamma), a cytokine essential for the lethal effects of endotoxin. We report here on the release of the nonfunctional subunit of IL-12, p40, as well as biologically active heterodimeric IL-12, p70, after administration of a lethal (n = 5) or sublethal (n = 8) dose of live Escherichia coli to baboons. Remarkably, on lethal challenge, peak levels of p40 were observed at 3 hours that were about twofold lower than those elicited after sublethal challenge (2,813 +/- 515 pg/mL v 4,972 +/- 732 pg/mL, P < .05). This disparity was also observed, although to a lesser extent, for IL-12 p70 antigen, of which maximum levels of 91 +/- 47 pg/mL and 151 +/- 41 pg/mL were measured 6 hours after a lethal or sublethal dose of E coli, respectively. Circulating p70 antigen correlated with IL-12 biologic activity (r = 0.869; P < .001). When comparing lethal to sublethal conditions, lower peak levels of IL-12 on lethal E coli sharply contrasted with higher levels of other proinflammatory cytokines, such as tumor necrosis factor (TNF)-alpha, IL-1beta, IL-6, and IL-8 observed in these animals. Lower IL-12 concentrations in the lethal group may have resulted in part from the enhanced production of IL-10, a known inhibitor of IL-12 synthesis in vitro, as peak levels of this cytokine 3 hours postchallenge inversely correlated with peak levels of IL-12, in particular p40 (r = -0.802; P < .01). Contrary to what might be expected if IFN-gamma were solely induced by IL-12, lethally challenged baboons generated threefold more IFN-gamma at 6 hours than those receiving a sublethal dose (P < .05). Moreover, higher levels of IFN- gamma were associated with lower p40/p70 ratios, suggesting that, in agreement with observations in vitro, IFN-gamma may have preferentially upregulated the release of p70 over p40. These data show that IL-12 is released in experimental septic shock in nonhuman primates and suggest that IL-10 and IFN-gamma are involved in the regulation of this release. Furthermore, this study indicates that the systemic release of IL-12 might be essential, but is not likely sufficient, to promote lethal production of IFN-gamma in sepsis. 相似文献
108.
Gurney B Wascher D Eaton L Benesh E Lucak J 《The Journal of orthopaedic and sports physical therapy》2008,38(5):238-245
STUDY DESIGN: Experimental laboratory study. OBJECTIVES: To measure the transmission of dexamethasone sodium phosphate (DEX-P) using iontophoresis as a function of skinfold tissue thickness and time elapsed between treatment and tissue extraction. BACKGROUND: Iontophoresis is a modality used in physical therapy with the intent to drive medications through the skin to underlying tissues using a direct electrical current. DEX-P is the most commonly used medication with iontophoresis and is used to treat a variety of connective tissue conditions. METHODS AND MEASURES: Sixteen adults undergoing anterior cruciate ligament reconstructive surgery using the semitendinosis/gracilis autograft received a 40-mA-min dose of iontophoresis with 0.4% DEX-P superficial to a slip of the distal semitendinosis tendon prior to surgery. The tendon slip was extracted within 4 hours. Time between treatment and tissue extraction and skinfold thickness were measured. Analysis was performed on the slip of the semitendinosis using high-performance liquid chromatography mass spectrum. RESULTS: Of the 16 subjects (10 female, 6 male; mean age, 33 years), 7 had measurable amounts of DEX-P in the tendon slip (4 female, 3 male; mean age, 34 years). The average concentration in the 16 subjects was 2.9 ng/g of tendon tissue. There was no correlation between DEX-P absorbed and skinfold thickness (r = -0.08, P = .79) or time elapsed (r = 0.25, P = .38). In a subset of the 7 individuals that showed measurable levels of DEX-P absorbed, the average concentration of DEX-P was 6.6 ng/g of tendon tissue, and there was a relationship between DEX-P concentrations and time elapsed that did not reach statistical significance (r = 0.71, P = .11). CONCLUSIONS: Iontophoresis appears to facilitate the transmission of dexamethasone to connective tissues in humans with skinfold thickness up to at least 30 mm. The absorption of the dexamethasone seemed to continue to occur for up to 4 hours after delivery. It is not clear why DEX-P was measured in only 7 of the 16 subjects. LEVEL OF EVIDENCE: Therapy, level 5. 相似文献
109.
110.
Background: Glycaemic control is a key issue in the care of people with diabetes mellitus (DM). Some studies have suggested a bidirectional relationship between glycaemic control and periodontal disease. Objectives: To investigate the relationship between periodontal therapy and glycaemic control in people with diabetes and to identify the appropriate future strategy for this question. Search strategy: A comprehensive approach was adopted employing handsearching; searching of electronic databases including the Cochrane Oral Health Group’s Trials Register, CENTRAL, MEDLINE, EMBASE, CINAHL, ZETOC, ISI Web of Knowledge and LILACS; contact with appropriate non‐English language healthcare professionals; authors and organizations. The final date for searching for studies was 24 March 2010. Selection criteria: This review studied randomized controlled trials of people with Type 1 or 2 diabetes mellitus (DM) with a diagnosis of periodontitis. Suitable interventions included mechanical periodontal therapy with or without adjunctives and oral hygiene education. Data collection and analysis: The titles and abstracts of 690 papers were examined by two review authors independently. Ultimately, seven studies were included and 19 excluded after full text scrutiny. All trials were assessed for risk of bias. Main results: Three studies had results pooled into a meta‐analysis. The effect for the mean percentage difference in HbA1c for scaling/root planing and oral hygiene (+/? antibiotic therapy) versus no treatment/usual treatment after 3–4 months was ?0.40% (95% confidence interval (CI) fixed effect ?0.78% to ?0.01%), representing a statistically significant reduction in HbA1c (P = 0.04) for scaling/root planing. One study was assessed as being at low risk of bias with the other two at moderate to high risk of bias. A subgroup analysis examined studies without adjunctive antibiotics ?0.80% (one study: 95% CI ?1.73% to 0.13%; P = 0.09), with adjunctive antibiotics in the test group ?0.36% (one study: 95% CI ?0.83% to 0.11%; P = 0.14), and with antibiotics in both test and control groups after 3/4 months ?0.15% (one study: 95% CI ?1.04% to 0.74%; P = 0.74). Authors’ conclusions: There is some evidence of improvement in metabolic control in people with diabetes, after treating periodontal disease. There are few studies available and individually these lacked the power to detect a significant effect. Most of the participants in the study had poorly controlled Type 2 DM with little data from randomized trials on the effects on people with Type 1 DM. 相似文献