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61.
62.
Field stimulation of the isolated main bronchi of the guinea-pig results in a rapid contraction followed by a sustained contractile response. Tetrodotoxin abolished these effects. The first phase was strongly inhibited by hyoscine, indicating that it was mediated mainly by excitation of cholinergic nerves. The lasting contraction was abolished by capsaicin tachyphylaxis but it was resistant to the effects of hyoscine, hexamethonium or physostigmine. It is suggested that capsaicin-sensitive non-cholinergic nerves have major excitatory effect on the guinea-pig bronchial smooth muscle and there is also evidence for their influence on the trachea.  相似文献   
63.
Morphological characteristics of cultured olfactory bulb cells   总被引:1,自引:0,他引:1  
Cultured olfactory bulb cells from embryonic mice had ultrastructural characteristics similar to those of many cell types in the intact adult mouse olfactory bulb. Identified cultured cells included mitral/tufted cells, granule cells, short-axon cells, and fibrous and protoplasmic astrocytes. Cultured neurons were found as individual cells, clusters or aggregates. Clusters consisted of a loose array of neurons that appeared to be densely interconnected by neurites. However, few neurites or fascicles emanated from clusters to adjoining areas. Aggregates consisted of many small, usually rounded, neurons piled on top of one larger neuron, or on more than one, with typically many neurites and fascicles projecting to adjacent aggregates, clusters or individual neurons. Neurites of cultured olfactory bulb cells were well developed, and some were several millimeters long. Synapses were very prominent in these cultures, especially in aggregates, clusters, and fascicles. Electron-lucent, dense-core, and coated vesicles were present. Polarity, shape, and length of the long axis (size) of 815 cultured neurons, identified by positive anti-microtubule-associated protein 2 staining, were documented. Cultured neurons varied in size from 9 to 27 m, with an average size of 16 m. Elliptical bipolar (35%), triangular multipolar (21%), and round unipolar (15%) were the most common polarity/shape combinations found in culture. Multipolar, triangular, triangular multipolar, and elliptical bipolar cells increased in size with increasing age of culture. The relative proportions of triangular, multipolar, elliptical multipolar, and triangular multipolar cells decreased, whereas the relative proportions of round, unipolar, and round unipolar cells increased with increasing age of culture. These changes in population subtypes and cell size may indicate continued differentiation and maturation of cultured neurons.  相似文献   
64.
Adenoid cystic carcinoma of the lower respiratory tract is an uncommon tumor that can arise in the mainstem bronchus and often presents as an endobronchial mass lesion causing bronchial obstruction with post obstructive atelectasis and pneumonia. Exfoliative cytology is seldom useful in the diagnosis of primary bronchial adenoid cystic carcinoma, because these neoplasms usually have a submucosal location with often intact mucosa. Since most endobronchial adenoid cystic carcinomas are endoscopically visible, bronchoscope-guided fine-needle aspiration constitutes an excellent approach to establish a pathologic diagnosis. The fine-needle aspiration cytology of primary pulmonary adenoid cystic carcinoma has been rarely described. We report a case of primary adenoid cystic carcinoma of the lung having characteristic cytologic features and correlate with computed tomography, bronchoscopic, and histological findings. Bronchoscope-guided aspiration cytology provided a conclusive diagnosis of adenoid cystic carcinoma, which was further corroborated by histology in the pneumonectomy specimen. Diagn. Cytopathol. 2004;30:51-56.  相似文献   
65.
Myelodysplastic syndromes (MDS) are associated with cell maturation defects that can manifest as abnormal surface antigen expression. We describe a patient with refractory anemia with excess blasts, who presented with infection and extensive dysplastic features in peripheral blood granulocytes. The granulocytes expressed CD11b, CD13, CD15, CD33, and CD43. The granulocytes also expressed CD4 antigen. Cytogenetic analysis showed a clonal t(5;12)(q33;p13). The patient improved on antibiotics with partial improvement in the dysplastic features. However, shortly after, the patient experienced paravertebral extramedullary blast transformation followed by a leukemia phase of acute monoblastic leukemia. The patient died a few days later. This is the first report describing anomalous expression of CD4 on granulocytes in MDS. Since the breakpoint on chromosome 12 is near the CD4 gene, which is mapped to 12p12, we hypothesize that dysregulation of the CD4 gene may have occurred resulting in its persistent expression on mature and maturing granulocytes.  相似文献   
66.
The exact mechanisms that regulate cervical softening or ripening during pregnancy are not completely understood. The aim of this study was to estimate the effects of various agents on cervical softening during pregnancy in rats. Cervical resistance was examined after treatment with nitric oxide (NO) donors and inhibitors and different hormonal agents. Cervical resistance was significantly reduced (P< 0.05) in rats treated with the NO donors: sodium nitroprusside, molsidomine and prostaglandin E(2). However, treatments with the NO synthase (NOS) inhibitors N(omega)-nitro-L-arginine methyl ester (L-NAME) and L-N(6)-1-iminoethyl-lysine (L-NIL), or the prostaglandin synthesis inhibitor, indomethacin, significantly increased resistance (P<0.05). The antiprogesterone, onapristone, reduced cervical resistance and its effects were only partially blocked by the progesterone agonist, promegestone. Relaxin reduced cervical resistance and NOS inhibitors partially blocked the effect of relaxin. These studies demonstrate that NO regulates cervical ripening. Relaxin also softens the cervix and may act by stimulating NO synthesis. Progesterone seems important in the control of cervical ripening, but its role appears complex. NO and prostaglandin pathways may independently control ripening by acting in parallel or synergistically.  相似文献   
67.
Few investigations have looked at behavioral stress outcomes in Alzheimer's caregivers. This study documented concentration deficits to examine behavioral outcomes of stress in 33 Alzheimer's Disease (AD) caregivers and in 33 age-, sex-, and race-matched controls. As hypothesized, caregivers showed less persistence than controls in solving problems from a standard test of problem-solving ability. In addition, caregivers tended to make more errors than controls on a standard proofreading task ( p < .09). In AD caregivers, cognitive deficits (represented by lower scores on problem-solving and concentration tasks) may be representative of a broader deficit in concentration that impairs the ability of caregivers to provide for their own needs and the needs of the family member for whom they are caring.  相似文献   
68.
The present investigation sought to determine whether the relationship between event-related potential (ERP) principal components analysis (PCA) factor scores and analogous waveform amplitude measures could be improved by high- and low-pass filtering the waveforms at a suitable cutoff value. Visual oddball ERPs were submitted to a varimax-rotated PCA performed on the variance/covariance matrix. Principal components corresponding to P300 and Slow Wave were obtained. In keeping with the fact that the variance/covariance PCA analyzes sources of variance around the grand mean waveform, the grand mean waveform was subtracted from each of the original waveforms, and baseline-referenced amplitude measurements were then made of P300 and Slow Wave. P300 was measured both as the maximum positive peak between 275 and 425 ms, and as the average amplitude during that interval. Slow Wave was measured as the average amplitude during the interval 400–700 ms. The P300 measurements were then repeated after high-pass filtering the difference waveforms at 2 Hz. Slow Wave measurements were repeated after low-pass filtering at 2 Hz. The value of 2 Hz was chosen as giving a reasonable cutoff based upon estimates of the wavelengths of the two components derived from inspection of their respective factor loading vectors. The correlation between factor scores and amplitude measurements was .94 for unfiltered Slow Wave and actually declined slightly but significantly to .91 when the waveforms were low-pass filtered. It would appear that Slow Wave factor scores emerging from a PCA can be fairly well approximated by a time-band measurement algorithm, and that this approximation is not improved by low-pass filtering. For both filtered and unfiltered measurements of P300, the amplitude/factor score correlation was significantly higher for the time-band method than for the peak method. Further, high-pass filtering at 2 Hz improved the time-band/factor score correlation significantly from .62 to .75. This improvement is probably because the unfiltered measurements were tapping sources of variance due both to the higher frequency P300 component as well as a simultaneously active, lower frequency Slow Wave component. Theoretical implications of these findings are discussed.  相似文献   
69.
The numbers of blood CD4+, CD8+, and CD4-CD8- T cells bearing alphabeta T-cell receptor (TCR) or gammadelta TCR molecules in males with a single missense mutation (L-->Q271) in the common gamma chain gene (gamma(c)) were investigated by flow cytometry. Virtually all XCIDL-->Q271 blood T cells that were CD4+ or CD8+ displayed alphabeta TCR but no gammadelta TCR. In contrast, CD4-CD8- T cells from affected males usually displayed gammadelta TCR, but no alphabeta TCR. The gammadelta TCR specificities were also studied. Except for the oldest subject, there was a direct relationship between blood CD3+ T cells that displayed gammadelta TCR and Vgamma9 and Vdelta2a specificities. Relative frequencies of CD3+ blood T cells that were Vgamma9+ or Vdelta2a+ were inversely related to age. In the oldest patient, the only detected gammadelta TCR specificity was Vdelta1. Thus, in contrast to mice with no gamma(c), XCIDL-Q271 blood T cells that bear gammadelta TCR with Vgamma9/Vdelta2a specificities develop but then decline in late childhood and thereafter. TCR with the Vdelta1 specificity then appear in older survivors with XCIDL-->Q271.  相似文献   
70.
Gamma interferon (IFN-gamma) is an important mediator of endotoxin (lipopolysaccharide [LPS])-induced immune responses. However, the specific cell types that produce IFN-gamma in response to LPS and the cellular factors that regulate LPS-induced IFN-gamma production have not been fully determined. The present studies were undertaken to characterize the cell populations that produce IFN-gamma after LPS challenge in the spleens of mice and to determine the regulatory factors that modulate LPS-induced production of IFN-gamma. Our studies show that the levels of splenic IFN-gamma mRNA and protein production peak at 6 and 8 h, respectively, after systemic LPS challenge. Approximately 60% of IFN-gamma-producing cells are natural killer (NK) cells (CD3(-)DX5(+)) and 25% are NKT cells (CD3(+)DX5(+)). Most of the remaining IFN-gamma-producing cells are T cells (CD3(+)DX5(-)), macrophages, and dendritic cells. Functionally, interleukin-12 (IL-12) is the major IFN-gamma-stimulating factor after LPS challenge, with costimulation provided by IL-15, IL-18, and B7 proteins. IL-10 is a major inhibitor of LPS-induced IFN-gamma production. Unlike intact heat-killed gram-negative and gram-positive bacteria, the class II major histocompatibility complex did not play a functional role in LPS-induced IFN-gamma production. LPS is a potent stimulus for splenic IL-10, IL-12 p40, and IL-15 mRNA expression, whereas IL-12 p35 and IL-18 mRNAs, as well as B7 proteins, are constitutively expressed in the mouse spleen. Of the factors studied, IL-18 serves as the most potent costimulus with IL-12 for IFN-gamma production, followed by IL-15 and B7 proteins. These data demonstrate that NK cells and NKT cells are the most abundant IFN-gamma-producing cells in the mouse spleen after LPS challenge and that IL-10 and IL-12 are key functional regulators of LPS-induced IFN-gamma production.  相似文献   
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