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71.
Autoimmune (type 1) diabetes mellitus in mouse, rat, and humans shares several features, including T lymphocyte infiltration into pancreatic islets and a dependence on permissive class II major histocompatibility complex (MHC) alleles. We report here on an experimental model involving mice that express influenza hemagglutinin (HA) under the control of the insulin promoter and, at the same time, a transgenic class II MHC-restricted T cell receptor (TcR) specific for an HA peptide. These mice spontaneously develop islet infiltrates resembling those found in NOD mice and most animals become diabetic within 8 weeks of age. Because of the availability of a clonotypic TcR antibody, we can be confident that the Ins-HA transgene does not induce any measurable alterations in the vast majority of T cells with the transgenic TcR in primary and secondary lymphoid organs. Continuous export of large numbers of HA-specific lymphocytes from the thymus was not required for the manifestation of the disease since mice thymectomized at 3 days after birth still developed the disease albeit with smaller infiltrates.  相似文献   
72.
In this review we focus on peptide- and peptidomimetic-based approaches that target autoimmune diseases and some pathologies of the central nervous system. Special attention is given to asthma, allergic rhinitis, osteoarthritis, and Alzheimer's disease, but other related pathologies are also reviewed, although to a lesser degree. Among others, drugs like Diacerhein and its active form Rhein, Pralnacasan, Anakinra (Kineret), Omalizumab, an antibody "BION-1", directed against the common beta-chain of cytokine receptors, are described below as well as attempts to target beta-amyloid peptide aggregation. Parts of the review are also dedicated to targeting of pathologic conditions in the brain and in other tissues with peptides as well as methods to deliver larger molecules through the "blood--brain barrier" by exploring receptor-mediated transport, or elsewhere in the body by using peptides as carriers through cellular membranes. In addition to highlighting current developments in the field, we also propose, for future drug targets, the components of the inflammasome protein complex, which is believed to initiate the activation of caspase- 1 dependent signaling events, as well as other pathways that signal inflammation. Thus we discuss the possibility of targeting inflammasome components for negative or positive modulation of an inflammatory response.  相似文献   
73.
Despite multiple sexual exposure to HIV-1 virus, some individuals remain HIV-1 seronegative (exposed seronegative, ESN). The mechanisms underlying this resistance remain still unclear, although a multifactorial pathogenesis can be hypothesised. Although several genetic factors have been related to HIV-1 resistance, the homozigosity for a mutation in CCR5 gene (the 32 bp deletion, i.e. CCR5-Delta32 allele) is presently considered the most relevant one. In the present study we analysed the genotype at CCR5 locus of 30 Italian ESN individuals (case group) who referred multiple unprotected heterosexual intercourse with HIV-1 seropositive partner(s), for at least two years. One hundred and twenty HIV-1 infected patients and 120 individuals representative of the general population were included as control groups. Twenty percent of ESN individuals had heterozygous CCR5-Delta 32 genotype, compared to 7.5% of HIV-1 seropositive and 10% of individuals from the general population, respectively. None of the analysed individuals had CCR5-Delta 32 homozygous genotype. Sequence analysis of the entire open reading frame of CCR5 was performed in all ESN subjects and no polymorphisms or mutations were identified. Moreover, we determined the distribution of C77G variant in CD45 gene, which has been previously related to HIV-1 infection susceptibility. The frequency of the C77G variant showed no significant difference between ESN subjects and the two control groups.  相似文献   
74.
75.
Asthma medication use in pregnancy and fetal growth   总被引:3,自引:0,他引:3  
BACKGROUND: Given the high prevalence of asthma in pregnancy, it is important to understand the relationship between asthma medications and fetal growth in the context of appropriate treatment. OBJECTIVE: This study examines the effect of inhaled corticosteroids, systemic corticosteroids, and beta(2)-agonists on fetal growth in 654 infants born to women with asthma compared with 303 infants born to controls without asthma. METHODS: Subjects for this prospective study were enrolled throughout North America between 1998 and 2003 and followed up by the Organization of Teratology Information Services. Incidence of small for gestational age (SGA) infants and mean birth size measures were compared among groups. RESULTS: Mean birth weight of full-term infants born to mothers who used systemic corticosteroids (3373 g) was lower than in the beta(2)-agonist group (3552 g) and controls without asthma (3540 g; P < .05) after adjustment for other risk factors. However, no differences in the incidence of SGA for weight were observed among groups. Adjusted mean birth length was slightly shorter in the systemic steroid group compared with controls (P=.02). Incidence of SGA for length and head circumference and mean head circumference did not vary among groups (P>.05). CONCLUSION: The treatment of asthma with systemic corticosteroids resulted in a deficit of about 200 g in birth weight compared with controls and exclusive beta(2)-agonist users and no increased incidence of SGA. These results suggest that asthma management with beta(2)-agonists and/or inhaled corticosteroids during pregnancy does not impair fetal growth, whereas systemic corticosteroids have a minimal effect which should be weighed against the necessity to control severe asthma.  相似文献   
76.
CD95 is a major apoptosis receptor that induces caspase activation and programmed cell death in susceptible cells. CD95-induced apoptosis can be blocked by peptidic caspase inhibitors such as benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone or Ile-Glu-Thr-Asp-fluoromethyl ketone. Here we show that stimulation of CD95 in the presence of these inhibitors induces necrosis and expression of various proinflammatory cytokines in primary T lymphocytes, such as TNF-alpha, IFN-gamma and granulocyte/macrophage colony-stimulating factor. In the absence of caspase inhibition CD95 stimulation did not result in cytokine expression, indicating that this proinflammatory signaling pathway is suppressed by active caspases. Further analysis with A3.01 T cells revealed that the proinflammatory signaling activity of CD95 was mediated by MEK/ERK, p38 and NF-kappaB signaling pathways. These findings point to a pivotal role of caspases not only as mediators of apoptosis but also as enzymes that prevent proinflammatory signaling during CD95-induced apoptosis. Moreover, our findings may be useful for the development of novel pharmacological strategies.  相似文献   
77.
Background: Several forms of psychotherapy aim at improving their patients' emotional expressivity, which is considered to contribute to mental health. Studies on the success of such attempts are virtually absent. Aim: To develop a measure for assessing changes of emotional expressivity in the course of psychotherapy. Method: In study 1 (N = 321), we generated a pool of German adjectives referring to emotional expressivity and reduced the number of those adjectives by means of factor‐analysis. In study 2 (N = 103), we determined how emotional expressivity is related to the Big Five personality factors. Results: An expressivity scale of 12 items with highly satisfactory psychometric properties was construed. Emotional expressivity is substantially related to Extraversion and moderately related to Agreeableness and Openness. Conclusion: The scale is ideally suited for repeated assessments in the course of psychotherapy in multi‐agent (e.g., inpatient) settings. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
78.
Mahogunin Ring Finger 1 (Mgrn1) encodes a RING-containing protein with ubiquitin ligase activity that has been implicated in pigment-type switching. In addition to having dark fur, mice lacking MGRN1 develop adult-onset spongy degeneration of the central nervous system and have reduced embryonic viability. Observation of complete situs inversus in a small proportion of adult Mgrn1 mutant mice suggested that embryonic lethality resulted from congenital heart defects due to defective establishment and/or maintenance of the left-right (LR) axis. Here we report that Mgrn1 is expressed in a pattern consistent with a role in LR patterning during early development and that many Mgrn1 mutant embryos show abnormal expression of asymmetrically expressed genes involved in LR patterning. A range of complex heart defects was observed in 20-25% of mid-to-late gestation Mgrn1 mutant embryos and another 20% were dead. This finding was consistent with 46-60% mortality of mutants by weaning age. Our results indicate that Mgrn1 acts early in the LR signaling cascade and is likely to provide new insight into this developmental process as Nodal expression was uncoupled from expression of other Nodal-responsive genes in Mgrn1 mutant embryos. Our work identifies a novel role for MGRN1 in embryonic patterning and suggests that the ubiquitination of MGRN1 target genes is essential for the proper establishment and/or maintenance of the LR axis.  相似文献   
79.
80.
The objectives of this investigation were to study the respiratory tract colonization and transmission of enterococci between 20 patients treated with mechanical ventilation at an intensive care unit (ICU), to compare genotyping with phenotyping, and to determine the antibiotic susceptibilities of the isolated enterococci. Samples were collected from the oropharynx, stomach, subglottic space, and trachea within 24 h of intubation, every third day until day 18, and thereafter every fifth day until day 33. Enterococcal isolates (n = 170) were analyzed by pulsed-field gel electrophoresis and with the PhenePlate (PhP) system. The antimicrobial susceptibilities to five agents were determined. Seventeen of the 20 subjects were colonized with enterococci in the respiratory tract; 12 were colonized in the lower respiratory tract. Genotype analyses suggested that 13 patients were involved in a transmission event, including all patients intubated more than 12 days. In conclusion, colonization of resistant enterococci in the respiratory tract of intubated patients treated at an ICU was common. Transmission of enterococci between patients occurred frequently. Prolonged intubation period seems to be a risk factor for enterococcal cross-transmission.  相似文献   
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