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1.

Interstitial lung disease (ILD) represents a significant cause of morbidity and mortality in systemic sclerosis (SSc). The purpose of this study was to examine recirculating lymphocytes from SSc patients for potential biomarkers of interstitial lung disease (ILD). Peripheral blood mononuclear cells (PBMCs) were isolated from patients with SSc and healthy controls enrolled in the Vanderbilt University Myositis and Scleroderma Treatment Initiative Center cohort between 9/2017–6/2019. Clinical phenotyping was performed by chart abstraction. Immunophenotyping was performed using both mass cytometry and fluorescence cytometry combined with t-distributed stochastic neighbor embedding analysis and traditional biaxial gating. This study included 34 patients with SSc-ILD, 14 patients without SSc-ILD, and 25 healthy controls. CD21lo/neg cells are significantly increased in SSc-ILD but not in SSc without ILD (15.4 ± 13.3% vs. 5.8 ± 0.9%, p = 0.002) or healthy controls (5.0 ± 0.5%, p < 0.0001). While CD21lo/neg B cells can be identified from a single biaxial gate, tSNE analysis reveals that the biaxial gate is comprised of multiple distinct subsets, all of which are increased in SSc-ILD. CD21lo/neg cells in both healthy controls and SSc-ILD are predominantly tBET positive and do not have intracellular CD21. Immunohistochemistry staining demonstrated that CD21lo/neg B cells diffusely infiltrate the lung parenchyma of an SSc-ILD patient. Additional work is needed to validate this biomarker in larger cohorts and longitudinal studies and to understand the role of these cells in SSc-ILD.

  相似文献   
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Annals of Surgical Oncology - The role of sentinel lymph node biopsy (SLNB) when ductal carcinoma in situ with microinvasion (DCISM) is identified on core biopsy is unclear. Our aim was to assess...  相似文献   
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The growing number of persons who have successful renal transplants and the challenges they undergo as they adjust to changed lifestyles increases the need for knowledge of the recipient's view of the changes resulting from the transplantation process. One area for exploration is the recipient's perception of the symptoms that occur after transplantation. The purpose of this study was to determine symptom occurrence and symptom distress following renal transplantation and their relationships to quality of life in patients with renal transplants.  相似文献   
5.
This study evaluated the short-term effectiveness of a mixed-gender sexual assault prevention program developed for college students. Program participants (n = 177) were compared to non-program participants (n = 132) prior to the program and during a 2-week follow-up period on measures of rape myths, victim empathy, perceived negative consequences and estimated likelihood of committing rape, sexual communication, sexual assault awareness, and risky dating behavior. The prevention program was effective at increasing men’s victim empathy and decreasing their adherence to rape myths but ineffective at changing women’s assault-related knowledge, participation in risky dating behaviors, and sexual communication strategies. Limitations of the study and directions for future research in sexual assault prevention are addressed. Editors’ Strategic Implications: This study provides an important example of the limitations of a single session prevention programming approach (even if it is well designed and executed) in addressing a systemic and pervasive problem like sexual assault on college campuses.  相似文献   
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Background: Animal and volunteer studies indicate that ropivacaine is associated with less neurologic and cardiac toxicity than bupivacaine. Ropivacaine may offer advantages when used for thoracic paravertebral block. This study was designed to describe the pharmacokinetics of ropivacaine after thoracic paravertebral block.

Methods: Twenty female patients undergoing elective unilateral breast surgery were randomly assigned to receive a single bolus thoracic paravertebral injection of 2 mg/kg ropivacaine, with or without 5 [mu]g/ml epinephrine. Simultaneous arterial and venous blood samples were obtained for plasma ropivacaine assay. Data were analyzed with NONMEM, using two possible absorption models: conventional first-order absorption and absorption following the inverse gaussian density function.

Results: Epinephrine reduced the peak plasma concentrations and delayed the time of peak concentration of ropivacaine in both the arterial and venous blood. The time course of drug input into the systemic circulation was best described by two inverse gaussian density functions. The median bioavailability of the rapid component was approximately 20% higher when epinephrine was not used. The mean absorption times were 7.8 min for the rapid absorption phase and 697 min for the slow absorption phase, with wide dispersion of the absorption function for the acute phase. The half-time of arterial-venous equilibration was 1.5 min.  相似文献   

8.
Nondysplastic hypotrophic and metaplastic epithelial alterations induced by dimethylbenz(a)anthracene in isogenic tracheal transplants were studied by light and electron microscopy 3--24 months after cessation of a 4-week carcinogen exposure. Hypotrophic epithelium observed at all time points was characterized by the presence of nonciliated cells that adopted either cuboidal or squamous shapes, forming simple or bistratified epithelia. Most of these cells, as well as some metaplastic cells, exhibited features of mucin-secreting cells. The metaplastic epithelia showed nonkeratinizing squamous metaplasia, closely related to transitional metaplasia, and keratinizing squamous metaplasia, which presented either an atrophic or an acanthotic epithelium. Although many of these epithelia showed morphologic features of normal stratified epithelia, several nonkeratinizing squamous metaplasias and acanthotic keratinizing squamous metaplasias exhibited some irregularities, probably representing very early atypical ultrastructural features (ie, perinuclear concentration of tonofilament bundles, the presence of dark and clear basal epithelial cells, interruptions and alterations of the basal lamina). These features were not observed in a group of early squamous metaplasias studied for comparative purposes 2 weeks after cessation of dimethylbenz(a)anthracene exposure, which were characterized by a combination of degenerative phenomena and increased cell proliferation.  相似文献   
9.
DNA polymerase mu (pol mu) is a novel error-prone DNA repair enzyme bearing significant structural homology with terminal deoxynucleotidyltransferase. Whereas other human error-prone DNA polymerases identified thus far show no preferential lymphoid tissue distribution, the highest levels of pol mu mRNA have been detected in peripheral lymphoid tissues, particularly germinal center B cells. Conceivably, up-regulation of the pol mu gene may be biologically significant in lymphomagenesis, especially in the development of B-cell non-Hodgkin's lymphomas (B-NHLs), because of enhanced error-prone DNA repair activities. To explore this possibility, we generated a digoxigenin-labeled riboprobe to pol mu mRNA and used the probe and in situ hybridization to examine the expression pattern of the pol mu gene in formalin-fixed, paraffin-embedded tissue sections of 37 B-NHLs. This included eight chronic lymphocytic leukemia/small lymphocytic lymphomas, six mantle cell lymphomas, seven follicular lymphomas, nine diffuse large B-cell lymphomas, three splenic marginal zone lymphomas, two Burkitt's lymphomas, and two precursor B-lymphoblastic lymphomas. We also correlated the pol mu mRNA expression levels with the tumor proliferation index, which was assessed in each case by image analysis of Ki-67 immunostained slides. Nineteen of 21 (90%) B-NHLs arising from postgerminal center B cells (follicular lymphomas, diffuse large B-cell lymphomas, splenic marginal zone lymphomas, and Burkitt's lymphomas) exhibited high expression of pol mu mRNA. In contrast, only 2 of 16 (13%) B-NHLs arising from pregerminal center B cells (chronic lymphocytic leukemia/small lymphocytic lymphomas, mantle cell lymphomas, and precursor B-lymphoblastic lymphomas) expressed significant levels of pol mu mRNA. Pol mu gene expression did not seem to correlate with the proliferation index, especially because a significant level of pol mu mRNA was not detected in either case of precursor B-lymphoblastic lymphomas. In conclusion, pol mu gene expression is highly associated with B-NHLs of postgerminal center B-cell derivation. Furthermore, the expression level is independent of the proliferation rate and thus is unrelated to the biological aggressiveness of the tumors. These findings, along with the error-prone nature of the enzyme, suggest that up-regulation of pol mu gene expression may be a contributing factor to the pathogenesis of a subset of B-NHLs through DNA repair-associated genomic instability.  相似文献   
10.
The purpose of our studies was to determine the growth and differentiation potential of Clara cells isolated from rabbit lungs. The Clara cell preparations were enriched (80 to 85%) by density gradient-elutriation procedures and then were inoculated into rat tracheas denuded of their own epithelium. These tracheas then were transplanted subcutaneously on the backs of nude mice. For purposes of comparison, other denuded tracheas were inoculated with mixed epithelial cells obtained from rabbit tracheas by enzymatic procedures. Control tracheas were inoculated with cell-free media. At 2, 4, and 14 weeks after transplantation, the tracheal grafts were removed from the recipient nude mice and examined by light and electron microscopy. Tracheal grafts not receiving cell inocula contained no epithelial lining, and the tracheal lumens were filled with loose connective tissue. Tracheas inoculated with 2 X 10(4) mixed tracheal cells showed a columnar, pseudostratified epithelium composed of five cell types: (a) poorly-differentiated cells, (b) ciliated cells, (c) mucous cells, (d) Clara-like cells, and (e) typical basal cells. A very different epithelium was established in tracheas repopulated with Clara cell isolates. This epithelium, at all time points examined, was cuboidal, single layered (never pseudostratified), and lacked basal cells. The tracheal lumens were lined with ciliated and nonciliated cells. The latter showed typical features of mature Clara cells (i.e., electron dense granules and smooth endoplasmic reticulum). At 14 weeks, the same two cell types were present, and often they were located on ridges and furrows of the tracheal walls. Mixed tracheal cells inoculated into denuded tracheas gave rise to a normal-appearing pseudostratified mucociliary epithelium, whereas the Clara cells inoculated under identical conditions gave rise to a low cuboidal epithelium resembling that seen in normal bronchioles. Establishment of these two types of epithelial linings occurred in the presence of the same mesenchymal components. Thus, we conclude that Clara cells have considerable self-renewal capacity, and their differentiation potential appears to be quite narrow.  相似文献   
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