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81.
STUDY OBJECTIVE: To evaluate the odds of being exposed to pesticides in asthmatic adults. DESIGN: A case-control study was performed in Lebanon. SETTING: People were approached when consulting physicians as outpatients. PATIENTS: Asthmatic patients and non-asthmatic controls in several Lebanese hospitals were interviewed. MAIN RESULTS: The study included 407 subjects from 10 medical centres. Any exposure to pesticides was associated to asthma (OR = 2.11 (1.47 to 3.02); p<10(-4)). Occupational use presented the highest association (OR = 4.98 (1.07 to 23.28); p = 0.02), followed by regional exposure (OR 3.51 (2.11 to 5.85); p<10(-4)). Results were confirmed by multivariate analysis, particularly for regional exposure (OR(a) = 2.78; p = 0.02) and house exposure (OR(a) = 2.17; p = 0.001). CONCLUSIONS: Results are comparable to those found in other studies; especially for occupational exposure. Pesticides toxicological effects may explain chronic respiratory symptoms and asthma associations found with all exposure types. Pesticide exposure was associated with asthma in Lebanese adults.  相似文献   
82.
BAP1 whose protein interacts with BRCA1 was analysed in a series of 47 French familial breast cancer cases negatively tested for BRCA1/2 mutations. The lack of detection of deleterious mutations suggests that BAP1 is not a high risk breast cancer predisposing gene. However, a common identified variant, rs123602, may be tested in sporadic cases as candidate for moderate risk.  相似文献   
83.
Besides epidermal growth factor receptor (EGFR) gene mutations, clinical factors such as smoking status have been identified as predictors for survival for NSCLC patients treated with EGFR-tyrosine kinase inhibitors (TKI). However, the biological screening for EGFR gene mutations is not routinely available everywhere. Therefore, the question arises if the decision to treat patients with EGFR-TKI should be based on clinical factors, and in particular smoking status, alone. We illustrate the difficulties faced by clinicians with the case of a 56-year-old man with stage IV lung adenocarcinoma and a smoking history of 30-pack-year. This patient received erlotinib first-line after its enrolment in a clinical trial. After 4 months, he presented with a dramatic clinical and radiological response. The biological analysis of the tumour revealed an EGFR exon 19 deletion. This report emphasizes that smoking status alone appears inappropriate in selecting patients for EGFR-TKI treatment. In addition, the relatively high number of (ex-)smokers retrieved from prospective studies on NSCLC patients with tumours showing an EGFR mutation should be emphasized, as it represents up to 30% of patients. Therefore, a biological rather than a clinical selection for patients' eligibility for EGFR-TKI appears mandatory.  相似文献   
84.
PURPOSE: The purpose of this study was to determine whether an ultra-endurance event is a strong stimulus to increase albumin synthesis involved in the process of intravascular albumin mass increase associated with transient hypervolemia. METHODS: The albumin synthetic rate was measured in six young men, 3 d before (C) and on the 1st (R1) and 8th (R8) days of the recovery from an ultra-endurance trial (5 h daily for 4 d). Albumin fractional (FSR) and absolute (ASR) synthetic rate were determined using a primed-constant infusion of [1(-13) C] leucine. Plasma volume (PV) using Evans Blue dye dilution and total body water (TBW) using bioelectrical impedance analysis were measured on C, R1, and R8. RESULTS: On R1 as compared with C: 1). PV (+23.3 +/- 3.2%; P相似文献   
85.
Soy infant formula which is fed to over half a million infants per year contains isoflavones such as genistein, which have been shown to be estrogenic at high concentrations. The developing testis is sensitive to estrogens, raising concern that the use of soy formulas may result in male reproductive toxicity. In the current study, male White-Dutch Landrace piglets received either sow milk (Sow), or were provided milk formula (Milk), soy formula (Soy), milk formula supplemented with 17-beta-estradiol (2 mg/kg/d) (M + E2) or supplemented with genistein (84 mg/L of diet; (M + G) from postnatal day 2 until day 21. E2 treatment reduced testis weight (p < 0.05) as percentage of body weight, significantly suppressed serum androgen concentrations, increased tubule area, Germ cell and Sertoli cell numbers (p < 0.05) relative to those of Sow or Milk groups. Soy formula had no such effects relative to Sow or Milk groups. mRNAseq revealed 103 differentially expressed genes in the M + E2 group compared to the Milk group related to endocrine/metabolic disorders. However, little overlap was observed between the other treatment groups. These data suggest soy formula is not estrogenic in the male neonatal piglet and that soy formula does not significantly alter male reproductive development.  相似文献   
86.
During epidemics, data from different sources can provide information on varying aspects of the epidemic process. Serology-based epidemiologic surveys could be used to compose a consistent epidemic scenario. We assessed the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG in serum samples collected from 7,837 blood donors in 7 cities of Brazil during March–December 2020. Based on our results, we propose a modification in a compartmental model that uses reported number of SARS-CoV-2 cases and serology results from blood donors as inputs and delivers estimates of hidden variables, such as daily values of SARS-CoV-2 transmission rates and cumulative incidence rate of reported and unreported SARS-CoV-2 cases. We concluded that the information about cumulative incidence of a disease in a city’s population can be obtained by testing serum samples collected from blood donors. Our proposed method also can be extended to surveillance of other infectious diseases.  相似文献   
87.
Bcl-2 homology domain 3 (BH3)-only pro-apoptotic proteins may play an important role in upstream cell death signaling pathways underlying ischemic brain injury. Puma is a potent BH3-only protein that can be induced via p53, FoxO3a and endoplasmic reticulum stress pathways and is upregulated by global cerebral ischemia. To more completely define the contribution of Puma to ischemic brain injury we measured the expressional response of Puma to transient focal cerebral ischemia in mice and also compared infarct volumes in puma-deficient versus puma-expressing mice. Real-time quantitative PCR determined puma mRNA levels were significantly increased 8 h after 90 min middle cerebral artery (MCA) occlusion in the ipsilateral cortex, while expression remained unchanged contralaterally. Puma protein levels were also increased in the ischemic cortex over the same period. However, cortical and striatal infarct volumes were not significantly different between puma-deficient and puma-expressing mice at 24 h, and no differences between genotypes were found for post-ischemic neurological deficit scores. These data demonstrate that focal cerebral ischemia is associated with puma induction but suggest that Puma does not contribute significantly to lesion development in the present model.  相似文献   
88.
We have shown that dermatophyte species can be easily identified on the basis of a DNA sequence encoding a part of the large-subunit (LSU) rRNA (28S rRNA) by using the MicroSeq D2 LSU rRNA Fungal Sequencing Kit. Two taxa causing distinct dermatophytoses were clearly distinguished among isolates of the Trichophyton mentagrophytes species complex.  相似文献   
89.
Several members of the Trypanosomatidae family, when freshly isolated from their mammalian hosts, have immunoglobulins adsorbed to their cell surfaces. However, a significant portion of these antibody molecules is not parasite specific, i.e., the immunoglobulins are bound to the parasite's cell surface molecules via noncognitive interactions. It has been proposed that this noncognitive adsorption of immunoglobulins to the parasite is mediated by an Fc-like receptor present in several members of the Trypanosomatidae family. However, the molecular identification of this receptor has never been defined. Here, we describe the cloning of a gene encoding a protein that might represent this molecule. The gene, named Lmsp1, was cloned by screening a Leishmania major cDNA expression library using a rabbit antiserum. Lmsp1 is present in both Leishmania and Trypanosoma and is expressed in all developmental stages of these parasites. The predicted protein has a molecular mass of 16.6 kDa and contains an RGD sequence starting at residue 104 and three cysteine residues at positions 55, 74, and 116. The purified recombinant protein strongly binds to normal immunoglobulins of various animal species (humans, rabbits, sheep, goats, guinea pigs, donkeys, rats, and mice) and the binding to human immunoglobulins appears to be immunoglobulin G (IgG) and IgM isotype specific. Moreover, Lmsp1 binds to both purified Fc and Fab fragments of IgG from both humans and rabbits. The mapping of the Lmsp1 epitopes that bind human IgG revealed that different sequences of the molecule bind to Fc or Fab. In addition, fluorescence-activated cell sorter analyses with a specific rabbit anti-Lmsp1 antiserum showed that Lmsp1 is associated with the parasite's cell surface. Finally, inhibition experiments point to an active role of this molecule in the immunoglobulin-mediated attachment and penetration of Trypanosoma cruzi in its macrophage host cells, thus suggesting that Lmsp1 is a putative Trypanosomatidae immunoglobulin receptor.  相似文献   
90.
V(D)J recombination not only comprises the molecular mechanism that insures diversity of the immune system but also constitutes a critical checkpoint in the developmental program of B and T lymphocytes. The analysis of human patients with severe combined immune deficiency (SCID) has enabled (and will enable in the future) the discovery of important factors involved in this reaction. The finding that the V(D)J recombinase apparatus includes components of the general DNA repair machinery of the cells has provided some new and interesting insights into the role of V(D)J recombination deficiency in the development of lymphoid malignancies, a hypothesis that has been tackled and proven in several animal models.  相似文献   
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