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Brixey JJ Robinson DJ Johnson CW Johnson TR Turley JP Zhang J 《ANS. Advances in nursing science》2007,30(1):E26-E42
An interruption was found to have no consistent definition in either healthcare or nonhealthcare literature. Walker and Avant's 8-step method of concept analysis was used to clarify, define, and develop a conceptual model of interruption. The analysis led to the identification of 5 defining attributes that include (1) a human experience; (2) an intrusion of a secondary, unplanned, and unexpected task; (3) discontinuity; (4) externally or internally initiated; and (5) situated within a context. Use of the defining attributes will be extended to form a category of interruption within a taxonomy of activity. 相似文献
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Gaya Spolverato Aslam Ejaz Yuhree Kim Georgios C. Sotiropoulos Andreas Pau Sorin Alexandrescu Hugo Marques Carlo Pulitano Eduardo Barroso Bryan M. Clary Luca Aldrighetti Todd W. Bauer Dustin M. Walters Ryan Groeschl T. Clark Gamblin Wallis Marsh Kevin T. Nguyen Ryan Turley Irinel Popescu Catherine Hubert Stephanie Meyer Jean-Francois Gigot Gilles Mentha Timothy M. Pawlik 《Journal of gastrointestinal surgery》2014,18(7):1284-1291
The association between tumor size and survival in patients with intrahepatic cholangiocarcinoma (ICC) undergoing surgical resection is controversial. We sought to define the incidence of major and microscopic vascular invasion relative to ICC tumor size, and identify predictors of microscopic vascular invasion in patients with ICC ≥5 cm. A total of 443 patients undergoing surgical resection for ICC between 1973 and 2011 at one of 11 participating institutions were identified. Clinical and pathologic data were evaluated using uni- and multivariate analyses. As tumor sized increased, the incidence of microscopic vascular invasion increased: <3 cm, 3.6 %; 3–5 cm, 24.7 %; 5–7 cm, 38.3 %; 7–15 cm, 32.9 %, ≥15 cm, 55.6 %; (p?<?0.001). Increasing tumor size was also found to be associated with worsening tumor grade. The incidence of poorly differentiated tumors increased with increasing ICC tumor size: <3 cm, 9.7 %; 3–5 cm, 19.8 %; 5–7 cm, 24.2 %; 7–15 cm, 21.1 %; >15 cm, 31.6 % (p?=?0.04). The presence of perineural invasion (odds ratio [OR]?=?2.98) and regional lymph node metastasis (OR?=?4.43) were independently associated with an increased risk of microscopic vascular invasion in tumors ≥5 cm (both p?<?0.05). Risk of microscopic vascular invasion and worse tumor grade increased with tumor size. Large tumors likely harbor worse pathologic features; this information should be considered when determining therapy and prognosis of patients with large ICC. 相似文献
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Interleukin-4 (IL-4) is a potent mediator of growth and differentiation of cells of several hematopoietic lineages. Interleukin-5 (IL-5) is a lineage-specific hematopoietic growth factor that stimulates the production of eosinophils and eosinophil colonies from normal human bone marrow cells. By using somatic cell hybrids and in situ chromosomal hybridization, we localized the IL-4 and IL-5 genes to human chromosome 5 at bands q23-31, a chromosomal region that is frequently deleted [del(5q)] in patients with myeloid disorders. By in situ hybridization, the IL-4 and IL-5 genes were found to be deleted in the 5q- chromosome of four patients with refractory anemia (RA) or therapy-related acute nonlymphocytic leukemia (t-ANLL), who had a del(5q). Thus a small segment of chromosome 5 contains IL-4, IL-5, IL- 3, and GM-CSF as well as other genes such as CD14 and EGR1. Our findings that each of these genes was deleted in the 5q- chromosome suggest that loss of function of one or more of these genes may play an important role in the pathogenesis of hematologic disorders associated with a del(5q). 相似文献
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To define further the role of hemin-controlled repressor (HCR) in globin synthesis, we studied its effect on the synthesis of individual globin chains in a rabbit reticulocyte lysate cell-free system. In the presence of HCR there was a marked globin chain imbalance, resulting in a lowered alpha/beta ratio. These findings in vitro may have relevance to certain clinical heme deficiency states in which a similar globin chain imbalance has been observed. 相似文献
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Kobayashi H; Montgomery KT; Bohlander SK; Adra CN; Lim BL; Kucherlapati RS; Donis-Keller H; Holt MS; Le Beau MM; Rowley JD 《Blood》1994,84(10):3473-3482
Translocations and deletions of the short arm of chromosome 12 [t(12p) and del(12p)] are common recurring abnormalities in a broad spectrum of hematologic malignant diseases. We studied 20 patients and one cell line whose cells contained 12p13 translocations and/or 12p deletions using fluorescence in situ hybridization (FISH) with phage, plasmid, and cosmid probes that we previously mapped and ordered on 12p12-13. FISH analysis showed that the 12p13 translocation breakpoints were clustered between two cosmids, D12S133 and D12S142, in 11 of 12 patients and in one cell line. FISH analysis of 11 patients with deletions demonstrated that the deletions were interstitial rather than terminal and that the distal part of 12p12, including the GDI-D4 gene and D12S54 marker, was deleted in all 11 patients. Moreover, FISH analysis showed that cells from 3 of these patients contained both a del(12p) and a 12p13 translocation and that the affected regions of these rearrangements appeared to overlap. We identified three yeast artificial chromosome (YAC) clones that span all the 12p13 translocation breakpoints mapped between D12S133 and D12S142. They have inserts of human DNA between 1.39 and 1.67 Mb. Because the region between D12S133 and D12S142 also represents the telomeric border of the smallest commonly deleted region of 12p, we also studied patients with a del(12p) using these YACs. The smallest YAC, 964c10, was deleted in 8 of 9 patients studied. In the other patient, the YAC labeled the del(12p) chromosome more weakly than the normal chromosome 12, suggesting that a part of the YAC was deleted. Thus, most 12p13 translocation breakpoints were clustered within the sequences contained in the 1.39 Mb YAC and this YAC appears to include the telomeric border of the smallest commonly deleted region. Whether the same gene is involved in both the translocations and deletions is presently unknown. 相似文献
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Flow cytometry detection of minimal residual disease in multiple myeloma: Lessons learned at FDA‐NCI roundtable symposium 下载免费PDF全文
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Hannah X Chu Hyun Ah Kim Seyoung Lee Jeffrey P Moore Christopher T Chan Antony Vinh Mathias Gelderblom Thiruma V Arumugam Brad RS Broughton Grant R Drummond Christopher G Sobey 《Journal of cerebral blood flow and metabolism》2014,34(3):450-459
We tested whether significant leukocyte infiltration occurs in a mouse model of permanent cerebral ischemia. C57BL6/J male mice underwent either permanent (3 or 24 hours) or transient (1 or 2 hours+22- to 23-hour reperfusion) middle cerebral artery occlusion (MCAO). Using flow cytometry, we observed ∼15,000 leukocytes (CD45+high cells) in the ischemic hemisphere as early as 3 hours after permanent MCAO (pMCAO), comprising ∼40% lymphoid cells and ∼60% myeloid cells. Neutrophils were the predominant cell type entering the brain, and were increased to ∼5,000 as early as 3 hours after pMCAO. Several cell types (monocytes, macrophages, B lymphocytes, CD8+ T lymphocytes, and natural killer cells) were also increased at 3 hours to levels sustained for 24 hours, whereas others (CD4+ T cells, natural killer T cells, and dendritic cells) were unchanged at 3 hours, but were increased by 24 hours after pMCAO. Immunohistochemical analysis revealed that leukocytes typically had entered and widely dispersed throughout the parenchyma of the infarct within 3 hours. Moreover, compared with pMCAO, there were ∼50% fewer infiltrating leukocytes at 24 hours after transient MCAO (tMCAO), independent of infarct size. Microglial cell numbers were bilaterally increased in both models. These findings indicate that a profound infiltration of inflammatory cells occurs in the brain early after focal ischemia, especially without reperfusion. 相似文献