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1.
Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy.  相似文献   
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Transient osteoporosis of the hip is an uncommon disorder of unclear etiology. It is often confused with other diagnosis including osteonecrosis of the femoral head. Authors describe a case of transient osteoporosis of the hip of 32 years woman. The symptoms occurred in third trimester of pregnancy. The primary symptoms were right hip pain and decreased range of motion of the right hip. In diagnostic process helpful were clinical examination, X-ray, ultrasonography, MRI and microscopic examination. As a treatment authors used walking on crutches, calcitonin and calcium preparate. After a few months remission of symptoms and normalization in accessory investigations were obtained.  相似文献   
4.
We investigated thrombin activatable fibrinolysis inhibitor (TAFI) and its influence on fibrinolysis by measuring pro-TAFI activity and total TAFI antigen in 38 patients with type I diabetes mellitus (18 with and 20 without microvascular complications), as well as in 20 healthy controls. The pro-TAFI levels in the two groups of patients did not differ from those in the control group. Total TAFI antigen [i.e. pro-TAFI, TAFI and inactive carboxypeptidase U (TAFIi)] tended to decrease in both the patient groups (59.7 +/- 7.2 and 73.4 +/- 8.9% with and without microvascular complications, respectively) compared with controls (91.9 +/- 12.2%) (P = 0.12). We also assessed the overall hemostatic potential (OHP) in plasma, the clot lysis time and the overall fibrinolytic potential. The OHP was significantly higher in patients with complications compared with controls (8.9 +/- 0.9 versus 6.7 +/- 0.4; P < 0.05) and also higher in the diabetics without complications (7.8 +/- 0.6), although the latter difference did not reach statistical significance. Levels of clot lysis time and overall fibrinolytic potential were similar in the two groups of patients and the controls. The increased OHP in plasma from diabetic patients with microvascular complications indicates an imbalance of the hemostatic system towards a prothrombotic state. No signs of impaired fibrinolysis were observed in patients with diabetes. Using the OHP method for estimation of overall hemostasis, it seems that TAFI does not influence either fibrinolysis or the increased thrombotic potential observed in patients with type I diabetes mellitus.  相似文献   
5.
In the present study, morphological examination of patients from two unrelated Polish families with CADASIL was performed. Using light microscopy, there were evident changes characteristic to the disease. On electron microscopy, deposits of granular osmiophillic material (GOM) were found not only in cerebral arteries and veins but also in cerebral capillaries and vessels of the internal organs. These findings indicate that pathological process in CADASIL is generalized and involves also small vessels devoid of smooth muscle cells. Therefore, we propose to consider a replacement for the name CADASIL that better reflects the morphological picture of the disease like, for example, cerebral autosomal dominant vasculopathy with subcortical infarcts and leukoencephalopathy (CADVaSIL) or, to preserve the commonly known acronym, cerebral autosomal dominant angiopathy with subcortical infarcts and leukoencephalopathy.  相似文献   
6.
The kinetics of gene expression associated with the development of cutaneous graft-versus-host disease (GVHD) were examined in a mouse model of MHC-matched allogeneic hematopoietic stem cell transplantation. Ear skin was obtained from recipient mice with or without GVHD between 7 and 40 days after transplantation for histopathological analysis and gene expression profiling. Gene expression patterns were consistent with early infiltration and activation of CD8(+) T and mast cells, followed by CD4(+) T, natural killer, and myeloid cells. The sequential infiltration and activation of effector cells correlated with the histopathological development of cutaneous GVHD and was accompanied by up-regulated expression of many chemokines and their receptors (CXCL-1, -2, -9, and -10; CCL-2, -5, -6, -7, -8, -9, -11, and -19; CCR-1 and CCR-5), adhesion molecules (ICAM-1, CD18, Ly69, PSGL-1, VCAM-1), molecules involved in antigen processing and presentation (TAP1 and TAP2, MHC class I and II, CD80), regulators of apoptosis (granzyme B, caspase 7, Bak1, Bax, and BclII), interferon-inducible genes (STAT1, IRF-1, IIGP, GTPI, IGTP, Ifi202A), stimulators of fibroblast proliferation and matrix synthesis (interleukin-1beta, transforming growth factor-beta1), and markers of keratinocyte proliferation (keratins 5 and 6), and differentiation (small proline-rich proteins 2E and 1B). Many acute-phase proteins were up-regulated early in murine cutaneous GVHD including serum amyloid A2 (SAA2), SAA3, serpins a3g and a3n, secretory leukocyte protease inhibitor, and metallothioneins 1 and 2. The kinetics of gene expression were consistent with the evolution of cutaneous pathology as well as with current models of disease progression during cutaneous GVHD.  相似文献   
7.
Zusammenfassung Das Vacciniavirus vermehrt sich schnell in den Organen von 1 tägigen Ratten, und die Tiere verenden am 2. oder 3. Tag nach der Infektion. In den Organen von 7 tägigen Ratten kann sich das Virus anfangs vermehren, später wird es aber eliminiert und die Tiere überleben. Bei 15tägigen Ratten wird das Virus eliminiert und die Tiere verenden nicht.Eintägige Ratten, die vor der Infektion Makrophagen erwachsener Tiere erhalten haben, kamen nicht ad exitum. Die Makrophagen von erwachsenen Ratten haben im Gegensatz zu Makrophagen von jungen Tieren die Fähigkeit, das phagozytierte Virus zu inaktivieren.Es wird daraus der Schluß gezogen, daß für die hohe Empfindlichkeit junger Ratten gegenüber Vacciniavirusinfektionen die funktionelle Unreife ihrer Makrophagen verantwortlich ist.
The role of macrophages in the pathogenicity of vaccinia virus for young rats
Summary Vaccinia viruses grew rapidly in organs of 1-day-old rats, and the animals died 2 or 3 days after infection. In the organs of 7-day-old rats the viruses replicated initially, but were later eliminated and the animals survived. The 15-day-old rats were capable of eliminating the viruses completely and did not die. When macrophages of adult animals were transferred to 1-day-old rats before infection the rats did not die. The macrophages of adult rats destroyed phagocytized viruses while those of young animals did not.The results suggest that this susceptibility of young rats to vaccinia virus infection is due to the functionally immature state of their macrophages.
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8.
Recent reports have suggested that different types of Ca2+-activated K+ channels may be selectively expressed either in the vascular endothelial cells (ECs) or smooth muscle cells (SMCs) of a single artery. In this study, we directly compared mRNA, protein and functional expression of the high-conductance Ca2+-activated K+ (BKCa) channel between freshly isolated ECs and SMCs from bovine coronary arteries. Fresh ECs and SMCs were enzymatically isolated, and their separation verified by immunofluorescent detection of α-actin and platelet/endothelium cell adhesion molecule (PECAM) proteins, respectively. Subsequently, studies using a sequence-specific antibody directed against the pore-forming α-subunit of the BKCa channel only detected its expression in the SMCs, whereas PECAM-positive ECs were devoid of the α-subunit protein. Additionally, multicell RT-PCR performed using cDNA derived from either SMCs or ECs only detected mRNA encoding the BKCaα-subunit in the SMCs. Finally, whole-cell recordings of outward K+ current detected a prominent iberiotoxin-sensitive BKCa current in SMCs that was absent in ECs, and the BKCa channel opener NS 1619 only enhanced K+ current in the SMCs. Thus, bovine coronary SMCs densely express BKCa channels whereas adjacent ECs in the same artery appear to lack the expression of the BKCa channel gene. These findings indicate a cell-specific distribution of Ca2+-activated K+ channels in SMCs and ECs from a single arterial site.  相似文献   
9.
This study evaluated a breast self-examination intervention to increase phase-specific self-efficacy and positive outcome expectancies. The role of social cognitive predictors in the process of behavior change was investigated. Using cluster randomization, participants were assigned to an intervention (n = 244) or to a control (n = 173) group. Controls were measured twice, with 13 weeks between the assessments. Respondents from the intervention group received the intervention before the 1st measurement. The increase in the number of self-examination components was significantly higher in the intervention group than among controls. Women who had never performed self-examinations before the intervention, as well as those who did it irregularly or incompletely, changed their behavior significantly. Results of structural equation modeling for a 2-group model showed that phase-specific self-efficacy was a significant predictor of intention, planning, and behavior change in the intervention group. In the control group, these relations were weaker or remained nonsignificant. Social cognitive variables measured in this study explained 15% of variance of behavior change in the control group and 29% of breast self-examination change in the intervention group.  相似文献   
10.
To study the role of Cdc42 in the establishment of epithelial polarity during mammalian development, we generated murine Cdc42-null embryonic stem cells and analyzed peri-implantation development using embryoid bodies (EBs). Mutant EBs developed endoderm and underlying basement membrane, but exhibited defects of cell polarity, cell-cell junctions, survival, and cavitation. These defects corresponded to a decreased phosphorylation and membrane localization of aPKC, a reduced phosphorylation of GSK3beta, and a diminished activity of Rac1. However, neither Rac1 nor the kinase function of GSK3beta seem to contribute to cell polarization and cell-cell contacts. In contrast, EBs expressing dominant-negative (dn) PKCzeta mimicked well the phenotype of Cdc42-null EBs, suggesting a major role of aPKC in mediating cell polarization downstream of Cdc42. Finally, aggregation experiments with endodermal cell lines suggested that Cdc42 might affect formation of adherens and tight junctions by PKCzeta-dependent regulation of the protein levels of p120 catenin and E-cadherin.  相似文献   
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