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71.
Progressive massive fibrosis is a well-recognized complication of long-term industrial dust exposure. Typically, it occurs in a setting of background parenchymal nodulation. We wish to report a case occurring in the absence of lung nodules.  相似文献   
72.
The Gongylonematid Nematode parasite of the Tunisian hedge-hog has been identified as Gongylonema mucronatum Seurat, 1916. The infective larva has been obtained from Locusta migratoria as intermediate host. The larval characters of this Gongylonema link it to the species G. pulchrum.  相似文献   
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Long-term results of the bulbourethral sling procedure   总被引:6,自引:0,他引:6  
PURPOSE: We evaluated the long-term efficacy of the male bulbourethral sling procedure in the treatment of post-radical prostatectomy urinary incontinence. MATERIALS AND METHODS: Between October 1994 and June 2000, 95 patients with post-radical prostatectomy incontinence underwent bulbourethral sling placement with tetrafluoroethylene bolsters at our hospital. Ultimately 71 of these patients responded to our questionnaire and they were classified into 2 groups. Group 1 consisted of 62 patients who had not undergone prior radiation therapy and group 2 consisted of 9 who had undergone radiation therapy before the sling procedure. Patients were asked to respond to questions regarding continence status as well as the validated Incontinence Quality of Life and International Prostate Symptom Score questionnaires. RESULTS: Mean followup from the most recent sling procedure was 4 years (range 0.27 to 6.55). Average patient age at questionnaire response was 74 years. A total of 86 procedures were performed on 71 patients. Of the 71 patients 7 underwent either sling removal or artificial urinary sphincter placement and were excluded from questionnaire analysis. Including retightening procedures 68% of the patients (72% of group 1, 43% of group 2) required 2 or less pads daily. Of the patients 36% (42% of group 1 and 14% of group 2) required 0 pads. CONCLUSIONS: The male bulbourethral sling procedure remains an effective treatment for post-prostatectomy incontinence at 4-year followup.  相似文献   
75.
PURPOSE: We calculated the prevalence of symptoms typically associated with interstitial cystitis (IC) in men and women in a managed care population in the Pacific Northwest. MATERIALS AND METHODS: International Classification of Diseases-9 based queries of the Kaiser Permanente Northwest, Portland, Oregon database were used to identify subjects with IC exclusion criteria, who were excluded from further analysis. A total of 10,000 questionnaires, including 5,000 for women and 5,000 for men, were mailed to subjects with codes indicating bladder symptoms and to those with none of the codes. The questionnaires included questions about the presence of IC symptoms and the O'Leary-Sant interstitial cystitis questionnaire. IC symptoms were defined in 2 ways, that is as 1) pelvic pain at least 3 months in duration plus urgency or frequency at least 3 months in duration and 2) the same criteria plus pain increasing as the bladder fills and/or pain relieved by urination. RESULTS: The prevalence of IC symptoms according to definitions 1 and 2 was 11.2% and 6.2% in women, and 4.6% and 2.3% in men, respectively. Symptoms were long-standing (duration greater than 1 year in 80% of cases) and bothersome (severity score 5 or greater in greater than 50%). Mean O'Leary-Sant interstitial cystitis questionnaire scores were 15.94 in subjects with definition 1 IC symptoms, 18.97 in those with definition 2 IC symptoms and 6.69 in those with no IC symptoms (p <0.001). Symptoms were most common and most severe in subjects previously diagnosed with IC. CONCLUSIONS: The prevalence of IC symptoms is 30 to 50-fold higher in women and 60 to 100-fold higher in men than the prevalence of a coded physician diagnosis of IC in the same population. Although these findings are not conclusive, they imply that IC may be significantly under diagnosed.  相似文献   
76.
Interactions between LPS and lung surfactant proteins   总被引:1,自引:0,他引:1  
After penetration into the lower airways, bacterial lipopolysaccharide (LPS) interacts with alveolar cells in a fluid environment consisting of pulmonary surfactant, a lipid-protein complex which prevents alveolar collapsing and participates in lung defense. The two hydrophilic surfactant components SP-A and SP-D are proteins with collagen-like and lectin domains (collectins) able to interact with carbohydrate-containing ligands present on microbial membranes, and with defined regions of LPS. This explains their capacity to damage the bacterial envelope and induce an antimicrobial effect. In addition, they modulate LPS-induced production of pro-inflammatory mediators in leukocytes by interaction with LPS or with leukocyte receptors. A third surfactant component, SP-C, is a small, highly hydrophobic lipopeptide which interacts with lipid A and reduces LPS-induced effects in macrophages and splenocyte cultures. The interaction of the different SPs with CD14 might explain their ability to modulate some LPS responses. Although the alveolar fluid contains other antiLPS and antimicrobial agents, SPs are the most abundant proteins which might contribute to protect the lung epithelium and reduce the incidence of LPS-induced lung injury. The presence of the surfactant collectins SP-A and SP-D in non-pulmonary tissues, such as the female genital tract, extends their field of action to other mucosal surfaces.  相似文献   
77.
Supernatant fluids from cultures of BCG-sensitized rabbit lymph node and spleen cells contained a factor that strongly agglutinated normal rabbit alveolar macrophages within 3 min at room temperature. In contrast, fluids from nonsensitized cell cultures did not agglutinate normal rabbit alveolar macrophages. This factor was designated macrophage-agglutinating factor (MAgF) because it is similar to the previously described factor found in lung lavages of rabbits exhibiting a BCG-induced pulmonary delayed hypersensitivity reaction. The kinetics of MAgF production in vitro by sensitized lymph node cells and its inhibition by puromycin and actinomycin D suggest active synthesis; sensitized spleen cells exhibited kinetics resembling release rather than synthesis. Studies on purified lymphocyte and macrophage populations from sensitized spleen and lymph nodes indicated that lymphocytes are responsible for MAgF production. However, MAgF production was not induced in normal cells incubated in vitro with concanavalin A or phytohemagglutinin. Fractionation of cell culture supernatant fluids in Sephadex G-100 or Ultrogel AcA-34 clearly separated MAgF from migration inhibition factor; MAgF was present in the void volume of the eluates, suggesting a molecular weight of over 400,000, whereas migration inhibition factor was recovered in the same peak as albumin. The role of MAgF in vivo is unknown, but it is postulated that it may cause the adherence of macrophages during granuloma formation.  相似文献   
78.
79.
Concomitant abuse of buprenorphine (BPN) and benzodiazepines (BZD) may relate to a pharmacodynamic interaction between the two. The objective of the present work was to investigate the acute and chronic effects of clorazepate (CRZ) alone or in combination with BPN on selective kappa opiate tritiated ligand [3H]-U69 593 and delta opiate radioligand [3H]-deltorphine II binding in the rat brain. Bmax (maximal receptor density) and Kd (the dissociation constant) were directly determined at different brain regions of interest (ROI) selected for high densities of kappa and/or delta receptors in rats treated with BPN and/or CRZ. The agents were administered either once or for 21 consecutive days. Differences in Bmax and Kd (for both specific ligands) were related to drug treatment and receptor location. Globally, single BPN administration induced no changes in kappa or delta opiate receptor binding, whereas repeated BPN administration up-regulated kappa receptor density and decreased delta affinity. At the kappa receptor level, repeated administration of CRZ acted only on Kd, whereas the delta receptor was up-regulated. Repeated addition of CRZ to BPN had no effect on kappa receptor Bmax versus chronic controls. By significantly decreasing Bmax, CRZ nullified the effect of chronic BPN on the kappa receptor. The modifications were strongest in the nucleus accumbens, where both types of receptor occur. Treatments had region-selective effects in some brain areas, such as the amygdala, periaqueductal gray matter, hypothalamus and caudate putamen. Increased mu and delta receptor densities would be expected to provide reinforcement by enhancing reward, and impairment of kappa receptor availability would be expected to decrease aversion. The effects described are likely to influence addictive behavior among people abusing BZD and BPN.  相似文献   
80.
Listeners are able to extract important linguistic information by viewing the talker's face-a process known as 'speechreading.' Previous studies of speechreading present small closed sets of simple words and their results indicate that visual speech processing engages a wide network of brain regions in the temporal, frontal, and parietal lobes that are likely to underlie multiple stages of the receptive language system. The present study further explored this network in a large group of subjects by presenting naturally spoken sentences which tap the richer complexities of visual speech processing. Four different baselines (blank screen, static face, nonlinguistic facial gurning, and auditory speech) enabled us to determine the hierarchy of neural processing involved in speechreading and to test the claim that visual input reliably accesses sound-based representations in the auditory cortex. In contrast to passively viewing a blank screen, the static-face condition evoked activation bilaterally across the border of the fusiform gyrus and cerebellum, and in the medial superior frontal gyrus and left precentral gyrus (p < .05, whole brain corrected). With the static face as baseline, the gurning face evoked bilateral activation in the motion-sensitive region of the occipital cortex, whereas visual speech additionally engaged the middle temporal gyrus, inferior and middle frontal gyri, and the inferior parietal lobe, particularly in the left hemisphere. These latter regions are implicated in lexical stages of spoken language processing. Although auditory speech generated extensive bilateral activation across both superior and middle temporal gyri, the group-averaged pattern of speechreading activation failed to include any auditory regions along the superior temporal gyrus, suggesting that f luent visual speech does not always involve sound-based coding of the visual input. An important finding from the individual subject analyses was that activation in the superior temporal gyrus did reach significance (p < .001, small-volume corrected) for a subset of the group. Moreover, the extent of the left-sided superior temporal gyrus activity was strongly correlated with speechreading performance. Skilled speechreading was also associated with activations and deactivations in other brain regions, suggesting that individual differences ref lect the efficiency of a circuit linking sensory, perceptual, memory, cognitive, and linguistic processes rather than the operation of a single component process.  相似文献   
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