全文获取类型
收费全文 | 1156篇 |
免费 | 41篇 |
专业分类
耳鼻咽喉 | 107篇 |
儿科学 | 16篇 |
妇产科学 | 20篇 |
基础医学 | 165篇 |
口腔科学 | 6篇 |
临床医学 | 54篇 |
内科学 | 245篇 |
皮肤病学 | 3篇 |
神经病学 | 163篇 |
特种医学 | 33篇 |
外科学 | 97篇 |
综合类 | 12篇 |
一般理论 | 3篇 |
预防医学 | 47篇 |
眼科学 | 19篇 |
药学 | 117篇 |
中国医学 | 1篇 |
肿瘤学 | 89篇 |
出版年
2023年 | 3篇 |
2022年 | 17篇 |
2021年 | 22篇 |
2020年 | 12篇 |
2019年 | 12篇 |
2018年 | 24篇 |
2017年 | 19篇 |
2016年 | 12篇 |
2015年 | 20篇 |
2014年 | 26篇 |
2013年 | 51篇 |
2012年 | 69篇 |
2011年 | 81篇 |
2010年 | 55篇 |
2009年 | 42篇 |
2008年 | 74篇 |
2007年 | 72篇 |
2006年 | 70篇 |
2005年 | 85篇 |
2004年 | 71篇 |
2003年 | 71篇 |
2002年 | 69篇 |
2001年 | 13篇 |
2000年 | 16篇 |
1999年 | 13篇 |
1998年 | 16篇 |
1997年 | 13篇 |
1996年 | 9篇 |
1995年 | 11篇 |
1993年 | 7篇 |
1992年 | 8篇 |
1990年 | 5篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1986年 | 6篇 |
1984年 | 7篇 |
1983年 | 7篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 6篇 |
1976年 | 3篇 |
1975年 | 8篇 |
1974年 | 6篇 |
1973年 | 4篇 |
1972年 | 5篇 |
1971年 | 6篇 |
1967年 | 3篇 |
排序方式: 共有1197条查询结果,搜索用时 15 毫秒
51.
52.
Pasquini G Barba M Hadidi A Faggioli F Negri R Sobol I Tiberini A Caglayan K Mazyad H Anfoka G Ghanim M Zeidan M Czosnek H 《Journal of virological methods》2008,147(1):118-126
Plum pox virus (PPV) is the most damaging viral pathogen of stone fruits. The detection and identification of its strains are therefore of critical importance to plant quarantine and certification programs. Existing methods to screen strains of PPV suffer from significant limitations such as the simultaneous detection and genotyping of several strains of PPV in samples infected with different isolates of the virus. A genomic strategy for PPV screening based on the viral nucleotide sequence was developed to enable the detection and genotyping of the virus from infected plant tissue or biological samples. The basis of this approach is a long 70-mer oligonucleotide DNA microarray capable of simultaneously detecting and genotyping PPV strains. Several 70-mer oligonucleotide probes were specific for the detection and genotyping of individual PPV isolates to their strains. Other probes were specific for the detection and identification of two or three PPV strains. One probe (universal), derived from the genome highly conserved 3' non-translated region, detected all individual strains of PPV. This universal PPV probe, combined with probes specific for each known strain, could be used for new PPV strain discovery. Finally, indirect fluorescent labeling of cDNA with cyanine after cDNA synthesis enhanced the sensitivity of the virus detection without the use of the PCR amplification step. The PPV microarray detected and identified efficiently the PPV strains in PPV-infected peach, apricot and Nicotiana benthamiana leaves. This PPV detection method is versatile, and enables the simultaneous detection of plant pathogens. 相似文献
53.
54.
M Pieścik-Lech H Szymański H Szajewska 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(10):e458-e464
Aim: To assess the efficacy and safety of a new oral rehydration solution (ORS) with improved flavour in the management of children with acute gastroenteritis (AGE). Methods: Children 4 to 48 months of age with AGE (≥3 loose or watery stools per day for >1 but <5 days) with mild‐to‐moderate dehydration (3% to 9% loss of body weight) according to the World Health Organization criteria randomly received regular hypotonic ORS (Na 60 mmol/L, glucose 78 mmol/L) or the same hypotonic ORS with an apple taste. Results: Of the 147 children randomized, 130 (88.4%) were available for intention‐to‐treat analysis. The proportion of children with the resolution of signs of dehydration in the experimental group compared with the control group was similar at 24 h (49/63 vs. 57/67, respectively, p = 0.28). There were also no significant differences in adequate weight gain (p = 0.48) and urine production at 24 h (p = 0.95) between groups. There were no differences between groups in any of the secondary outcome measures, including ORS intake. No adverse events were observed in the study groups. Conclusions: In an outpatient setting, there was no difference in efficacy between the study products. Both ORSs were equally effective and may be used interchangeably. 相似文献
55.
Sułowska Z Majewska E Tchórzewski H Klink M 《Archivum immunologiae et therapiae experimentalis》2003,51(4):267-272
Polymorphonuclear leukocyte (neutrophil) apoptosis is an important mechanism regulating the life span and some functions of neutrophils at inflamed sites. Opioid peptides are present in the peripheral circulation and their concentrations rapidly increase as a result of stress and inflammation. The effect of opioid peptides such as met-enkephalin (M-ENK) and beta-endorphin (beta-END) on tumor necrosis factor (TNF)-alpha-induced apoptosis in human neutrophils in vitro was investigated. Neutrophils isolated from peripheral blood were cultured in the absence or presence of 10(-6)-10(-10) M of opioid peptides for 8, 12 and 18 h. Features of apoptotic neutrophils were measured by a flow cytometric method based on analysis of the apoptotic nuclei (DNA content). We found that M-ENK and beta-END enhanced both uninduced and TNF-alpha-induced neutrophil apoptosis in vitro in a dose-dependent manner. The effect of opioid peptides on the modulation of neutrophil apoptosis was not reversed by the opioid-receptor antagonist naloxone. The results suggest that M-ENK and beta-END can regulate neutrophil life span via apoptosis and in this way may participate in the resolution of inflammation. 相似文献
56.
Elastofibroma dorsi (EFD) is a relatively rare soft tissue mass, probably of reactive nature. The lesion is typically located near the inferior margin of the scapula or between the inferior part of scapula and the chest wall in elderly women. Although location of the tumor together with the age/sex of the patients and radiologic findings is often suggestive of the diagnosis, tissue examination has been considered necessary to confirm the diagnosis. Although the histologic features of EFD are well known, there are only four single case reports of the cytologic findings in the English language literature. We describe the cytologic features of EFD in five patients with correlations to clinical, radiologic, histologic, and electron microscopic findings. The current study suggests that the fine-needle aspiration (FNA) features are highly diagnostic, permitting a firm diagnosis of EFD in a typical clinical setting and eliminating the need for preoperative histologic examination. 相似文献
57.
Domanski HA Akerman M Engellau J Gustafson P Mertens F Rydholm A 《Diagnostic cytopathology》2006,34(6):403-412
The preoperative fine-needle aspiration cytology (FNAC) diagnoses in 116 surgically excised neurilemomas were reviewed and compared with the corresponding histopathologic diagnoses made on surgical specimens and with clinical data. In addition, the utility of adjunctive techniques was analyzed and other spindle-cell lesions in the differential diagnoses were discussed. An unequivocal, benign diagnosis was rendered by FNAC in 80 cases, 67 of which were correctly labelled as neurilemoma in a review of the original cytology reports. There were 6 false-positive malignant diagnoses while 23 smears were considered insufficient and 7 inconclusive as to whether benign or malignant. On reevaluation, the diagnostic smears in most cases contained spindle cells with wavy nuclei embedded in a fibrillar, occasionally collagenous, and/or myxoid matrix and Antoni A/Antoni B tissue fragments. A moderate to abundant admixture of round to oval cells was also frequent. Nuclear palisading was seen in 41 smears with distinctive Verocay bodies in 10. Markedly pleomorphic nuclei were seen in smears from 8 ancient and 6 conventional neurilemomas, and slight to moderate nuclear pleomorphism was observed in 38 additional cases. Thus most neurilemomas have distinct cytomorphologic features that allow correct diagnosis. The major problem in FNAC of neurilemoma is to obtain sufficient material. Furthermore aspirates showing predominantly Antoni A features, nuclear pleomorphism, and/or myxoid changes can easily be confused with other types of benign or malignant soft-tissue tumors. 相似文献
58.
Indications for allogeneic stem cell transplantation in chronic lymphocytic leukemia: the EBMT transplant consensus. 总被引:5,自引:0,他引:5
P Dreger P Corradini E Kimby M Michallet D Milligan J Schetelig W Wiktor-Jedrzejczak D Niederwieser M Hallek E Montserrat 《Leukemia》2007,21(1):12-17
The aim of this project was to identify situations where allogeneic stem cell transplantation (allo-SCT) might be considered as a preferred treatment option for patients with B-cell chronic lymphocytic leukemia (CLL). Based on a MEDLINE search and additional sources, a consented proposal was drafted, refined and approved upon final discussion by an international expert panel. Key elements of the consensus are (1) allo-SCT is a procedure with evidence-based efficacy in poor-risk CLL; (2) although definition of 'poor-risk CLL' requires further investigation, allo-SCT is a reasonable treatment option for younger patients with (i) non-response or early relapse (within 12 months) after purine analogues, (ii) relapse within 24 months after having achieved a response with purine-analogue-based combination therapy or autologous transplantation, and (iii) patients with p53 abnormalities requiring treatment; and (3) optimum transplant strategies may vary according to distinct clinical situations and should be defined in prospective trials. This is the first attempt to define standard indications for allo-SCT in CLL. Nevertheless, whenever possible, allo-SCT should be performed within disease-specific prospective clinical protocols in order to continuously refine transplant indications according to new developments in risk assessment and treatment of CLL. 相似文献
59.
Autoschizis: a novel cell death 总被引:10,自引:0,他引:10
Jamison JM Gilloteaux J Taper HS Calderon PB Summers JL 《Biochemical pharmacology》2002,63(10):1773-1783
Vitamin C (VC) and vitamin K(3) (VK(3)) administered in a VC:VK(3) ratio of 100:1 exhibit synergistic antitumor activity and preferentially kill tumor cells by autoschizis, a novel type of necrosis characterized by exaggerated membrane damage and progressive loss of organelle-free cytoplasm through a series of self-excisions. During this process, the nucleus becomes smaller, cell size decreases one-half to one-third of its original size, and most organelles surround an intact nucleus in a narrow rim of cytoplasm. While the mitochondria are condensed, tumor cell death does not result from ATP depletion. However, vitamin treatment induces a G(1)/S block, diminishes DNA synthesis, increases H(2)O(2) production, and decreases cellular thiol levels. These effects can be prevented by the addition of catalase to scavenge the H(2)O(2). There is a concurrent 8- to 10-fold increase in intracellular Ca(2+) levels. Electrophoretic analysis of DNA reveals degradation due to the caspase-3-independent reactivation of deoxyribonuclease I and II (DNase I, DNase II). Redox cycling of the vitamins is believed to increase oxidative stress until it surpasses the reducing ability of cellular thiols and induces Ca(2+) release, which triggers activation of Ca(2+)-dependent DNase and leads to degradation of DNA. Recent experiments indicate that oral VC:VK(3) increases the life-span of tumor-bearing nude mice and significantly reduces the growth rate of solid tumors without any significant toxicity by reactivating DNase I and II and inducing autoschizis. This report discusses the mechanisms of action employed by these vitamins to induce tumor-specific death by autoschizis. 相似文献
60.
The consistency of the cellular yield as obtained by radiologically guided fine-needle aspiration biopsy (FNAB) was investigated in 29 cases with bone lesions. Aspirates from three different sites of the same lesion were analysed randomly and independently by two cytologists unaware of the clinical and radiological findings.The series was grouped cytologically into four categories: (1) benign, (2) sarcoma, (3) other malignancy, (4) non-conclusive. A lesion was considered cytologically homogenous, when all three aspirates were identically categorised. Among 29 lesions, 13 and 12, respectively, were assessed as homogeneous by the two cytologists. In the remaining lesions, heterogeneity almost exclusively pertained to the mixture of conclusive and non-conclusive aspirates. An alternative diagnosis was suggested in one case by each cytologist. Comparison of the two cytologists' assessments showed that 21 cases were compliant, i.e., no inter-observer difference in 63 out of 87 aspirates. In the remaining eight cases (24 aspirates), non-compliance was mainly due to differences between the cytologists in the ratio of conclusive versus non-conclusive aspirates. Only the analysis of one and the same aspirate resulted in two different diagnoses. A correct diagnosis was given by the cytologists in 22 and 23 cases, incorrect in two and non-conclusive in five and four, respectively.Our cytological study of bone lesions, albeit limited, suggests that true tumour heterogeneity is rare. The non-compliance between the two cytologists and the diagnostic difficulties should mainly be attributed to the blind, random approach of the study.The main problem of FNAB pertains to the high rate of non-conclusive aspirates.This, however, does not entail an increased risk of incorrect diagnosis, but rather prompts repeat FNAB. 相似文献