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71.
We aimed to demonstrate that depression and hypertension are associated independently of each other with disability and cognitive impairment in older subjects and that such an association is not attributable to number and severity of comorbidities. An observational study was performed on elderly patients admitted to the Hospital Network of the Italian National Research Center on Aging (INRCA) from January 2005 to December 2006. Depression was defined according to 15-item geriatric depression scale (GDS) score; physical disability according to activities of daily living (ADL) and instrumental activities of daily living (IADL) scores; cognitive impairment on the mini-mental state examination (MMSE) test; the number and severity of comorbidities by means of physician-administered cumulative illness rating scale (CIRS). Among 6180 older subjects (age = 79.3 ± 5.8 years; 47% men), 48.3% were normotensive, 21.8% normotensive depressed, 21.7% hypertensive, and 8.2% hypertensive and depressed. Both depression and hypertension remained significantly associated with functional disability and cognitive impairment. When controlling for age, gender, the number and severity of comorbidities, hypertension was associated with a significantly higher likelihood of having functional disability or cognitive impairment only in the presence of depression (odds ratio = OR = 2.02, 95% confidence interval = 95%CI = 1.60-2.54, p < 0.001 for functional disability; OR = 2.21, 95%CI = 1.79-2.74, p < 0.001 for cognitive impairment) as compared to normotensive controls without depression. We conclude that depression per se’ or co-occurrence of hypertension and depression is associated with higher functional disability and cognitive impairment in older subjects. This effect is not attributable to the number or to the severity of comorbidities.  相似文献   
72.
Neuropeptide Y (NPY) plays an important role in stress, anxiety, obesity, and energy homeostasis via activation of NPY-Y1 receptors (Y1Rs) in the brain. However, global knockout of the Npy1r gene has low or no impact on anxiety and body weight. To uncover the role of limbic Y1Rs, we generated conditional knockout mice in which the inactivation of the Npy1r gene was restricted to excitatory neurons of the forebrain, starting from juvenile stages (Npy1r(rfb)). Npy1r(rfb) mice exhibited increased anxiety and reduced body weight, less adipose tissue, and lower serum leptin levels. Npy1r(rfb) mutants also had a hyperactive hypothalamic-pituitary-adrenocortical axis, as indicated by higher peripheral corticosterone and higher density of NPY immunoreactive fibers and corticotropin releasing hormone immunoreactive cell bodies in the paraventricular hypothalamic nucleus. Importantly, through fostering experiments, we determined that differences in phenotype between Npy1r(rfb) and Npy1r(2lox) mice became apparent when both genotypes were raised by FVB/J but not by C57BL/6J dams, suggesting that limbic Y1Rs are key targets of maternal care-induced programming of anxiety and energy homeostasis.  相似文献   
73.
Objectives: To investigate the molecular epidemiology of fluoroquinolone-resistant (FQ-R) and fluoroquinolone-susceptible (FQ-S) bacteremic Escherichia coli isolates from neutropenic patients by pulsed-field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD) analysis.
Methods: Nineteen FQ-R and 27 FQ-S isolates of E. coli , obtained from patients on a hematologic ward over a 7-year period, were genotyped by PFGE and RAPD using two different random primers (1247 and 1283).
Results: PFGE analysis was able to type all FQ-S isolates and most (17/19, 89%) FQ-R isolates of E. coli . All isolates were genotypically unrelated, with the exception of two indistinguishable FQ-R isolates from different patients in the same period. RAPD analysis typed all isolates, including those FQ-R isolates untypable by PFGE, but was unable to distinguish between some isolates that were different by PFGE. Using primer 1247, RAPD analysis identified six pairs and one triad, while primer 1283 identified seven pairs and one triad of indistinguishable isolates.
Conclusions: No spread of epidemic FQ-R or FQ-S E. coli isolates was documented among neutropenic patients. RAPD analysis is a powerful genotyping method, but appeared to be less reproducible and discriminatory than PFGE for investigating E. coli isolates.  相似文献   
74.
75.
This study analyzes the pathologic and molecular features of 5 cases of primary cutaneous large B-cell lymphoma of the leg (PCLBCL-leg), recently included in the European Organization for Research and Treatment of Cancer (EORTC) classification of primary cutaneous lymphoma. PCLBCL-leg accounts for 5% to 10% of all primary cutaneous B-cell lymphoma (PCBCL), usually affects elderly patients and carries a worse prognosis than other forms of PCBCL. It has been proposed that the malignant cells of PCLBCL-leg originate from germinal center (GC)-related cells, but their effective normal counterpart is unclear, and the rationale behind the inclusion of this lymphoma as a separate entity is based on its prognosis rather than on its proved histogenesis. All of our cases of PCLBCL-leg morphologically resembled diffuse large B-cell lymphoma (DLBCL), but to better define their histogenesis, we also analyzed various phenotypic and genotypic markers, including mutations of the Ig and of BCL-6 genes, as well as expression of the bcl-6, MUM1, and CD138/syndecan-1 proteins. Immunohistochemically, all of our cases stained for the L-26/CD20cy and CD79a antigens and expressed the bcl-2, bcl-6, and MUM-1 proteins but were negative for both the CD10/CALLA and CD138 antigens. With respect to molecular analysis, the lymphoma population of all PCLBCL-leg carried hypermutation of Ig genes, and all but 1 case also harbored mutations of the BCL-6 gene. Our results indicate that PCLBCL-leg are similar both under the morphofunctional and molecular profiles to most DLBCL of other sites. Thus, caution seems justified before definitely considering PCLBCL of the leg as a distinct entity.  相似文献   
76.
Natural killer (NK) cell function is largely modulated by growth factors and cytokines. In particular, interleukin (IL)-2, IL-12, and IL-15 have major effects on the proliferative and cytotoxic activities of NK cells against tumor and virus-infected cells. It is thought that the members of the protein kinase C (PKC) family of serine/threonine kinases play an important role in mediating the pleiotropic effects of cytokines on their target cells. We have investigated the downstream effects generated in purified human NK cells by IL-2, IL-12, and IL-15 on PKCalpha and PKCepsilon--a canonical and a novel isoform of PKC, respectively. By means of Western blotting, PKC activity assays, and immunofluorescence performed on highly purified preparations of primary human NK cells, we demonstrate that: 1) the three cytokines have similar effects on PKCalpha and PKCepsilon activities; 2) whereas PKCepsilon activity is induced by cytokine stimulation, PKCalpha activity is inhibited; and 3) both the induction of PKCepsilon and the inhibition of PKCalpha functional activity are relatively early events in NK cells, while longer cytokine stimulations do not generate significant variations in enzyme activity, suggesting that the activation of both the canonical and novel isoforms of PKC are events required in the early phases of cytokine-induced NK cell stimulation.  相似文献   
77.
Thirteen patients with acute myeloid leukemia, 5 with active disease, 2 in molecular relapse, and 6 in morphologic complete remission (CR; median age, 62 years; range, 53-73 years) received highly purified CD56(+)CD3(-) natural killer (NK) cells from haploidentical killer immunoglobulin-like receptor-ligand mismatched donors after fludarabine/cyclophosphamide immunosuppressive chemotherapy, followed by IL-2. The median number of infused NK cells was 2.74 × 10(6)/Kg. T cells were < 10(5)/Kg. No NK cell-related toxicity, including GVHD, was observed. One of the 5 patients with active disease achieved transient CR, whereas 4 of 5 patients had no clinical benefit. Both patients in molecular relapse achieved CR that lasted for 9 and 4 months, respectively. Three of 6 patients in CR are disease free after 34, 32, and 18 months. After infusion, donor NK cells were found in the peripheral blood of all evaluable patients (peak value on day 10). They were also detected in BM in some cases. Donor-versus-recipient alloreactive NK cells were shown in vivo by the detection of donor-derived NK clones that killed recipient's targets. Adoptively transferred NK cells were alloreactive against recipient's cells, including leukemia. In conclusion, infusion of purified NK cells is feasible in elderly patients with high-risk acute myeloid leukemia. This trial was registered at www.clinicaltrial.gov as NCT00799799.  相似文献   
78.
Although combination regimens have improved outcomes over monotherapy in chronic lymphocytic leukemia (CLL), patients eventually relapse. Combined fludarabine, cyclophosphamide, and monoclonal anti-CD52 antibody alemtuzumab (FCC) provided synergistic cytotoxicity with effective clearing of minimal residual disease. This phase 2 study determined FCC efficacy and safety in relapsed/refractory CD52(+) B-CLL after ≥ 1 line of treatment. From January 2005 through June 2008, up to 6 courses of oral fludarabine 40 mg/m2 per day, oral cyclophosphamide 250 mg/m2 per day, and subcutaneous alemtuzumab (Mab-Campath) 10 mg (increased to 20 mg after first 10-patient cohort) were administered days 1 to 3 every 28 days. The primary objective was overall response rate (ORR); secondary objectives included response duration, time to disease progression, and safety and tolerability. ORR was 67% in 43 patients; 30% achieved complete response. ORR significantly improved with 1 versus ≥ 2 prior therapies (P = .018), and without versus with previous monoclonal antibody treatment (P = .003). Median progression-free survival was 24.4 months, not reached in patients achieving complete response. Median overall survival was 33.6 months. Myelosuppression was the most common adverse event, with a low percentage of cytomegalovirus reactivations and manageable infections. However, close vigilance of opportunistic infections is warranted. FCC provides effective immunotherapy in relapsed/refractory CLL, including in patients with poor-risk prognostic factors.  相似文献   
79.
Enterococcal implant-associated infections are difficult to treat because antibiotics generally lack activity against enterococcal biofilms. We investigated fosfomycin, rifampin, and their combinations against planktonic and adherent Enterococcus faecalis (ATCC 19433) in vitro and in a foreign-body infection model. The MIC/MBClog values were 32/>512 μg/ml for fosfomycin, 4/>64 μg/ml for rifampin, 1/2 μg/ml for ampicillin, 2/>256 μg/ml for linezolid, 16/32 μg/ml for gentamicin, 1/>64 μg/ml for vancomycin, and 1/5 μg/ml for daptomycin. In time-kill studies, fosfomycin was bactericidal at 8× and 16× MIC, but regrowth of resistant strains occurred after 24 h. With the exception of gentamicin, no complete inhibition of growth-related heat production was observed with other antimicrobials on early (3 h) or mature (24 h) biofilms. In the animal model, fosfomycin alone or in combination with daptomycin reduced planktonic counts by ≈4 log10 CFU/ml below the levels before treatment. Fosfomycin cleared planktonic bacteria from 74% of cage fluids (i.e., no growth in aspirated fluid) and eradicated biofilm bacteria from 43% of cages (i.e., no growth from removed cages). In combination with gentamicin, fosfomycin cleared 77% and cured 58% of cages; in combination with vancomycin, fosfomycin cleared 33% and cured 18% of cages; in combination with daptomycin, fosfomycin cleared 75% and cured 17% of cages. Rifampin showed no activity on planktonic or adherent E. faecalis, whereas in combination with daptomycin it cured 17% and with fosfomycin it cured 25% of cages. Emergence of fosfomycin resistance was not observed in vivo. In conclusion, fosfomycin showed activity against planktonic and adherent E. faecalis. Its role against enterococcal biofilms should be further investigated, especially in combination with rifampin and/or daptomycin treatment.  相似文献   
80.
Increasing antimicrobial resistance reduces treatment options for implant-associated infections caused by methicillin-resistant Staphylococcus aureus (MRSA). We evaluated the activity of fosfomycin alone and in combination with vancomycin, daptomycin, rifampin, and tigecycline against MRSA (ATCC 43300) in a foreign-body (implantable cage) infection model. The MICs of the individual agents were as follows: fosfomycin, 1 μg/ml; daptomycin, 0.125 μg/ml; vancomycin, 1 μg/ml; rifampin, 0.04 μg/ml; and tigecycline, 0.125 μg/ml. Microcalorimetry showed synergistic activity of fosfomycin and rifampin at subinhibitory concentrations against planktonic and biofilm MRSA. In time-kill curves, fosfomycin exhibited time-dependent activity against MRSA with a reduction of 2.5 log10 CFU/ml at 128 × the MIC. In the animal model, planktonic bacteria in cage fluid were reduced by <1 log10 CFU/ml with fosfomycin and tigecycline, 1.7 log10 with daptomycin, 2.2 log10 with fosfomycin-tigecycline and fosfomycin-vancomycin, 3.8 log10 with fosfomycin-daptomycin, and >6.0 log10 with daptomycin-rifampin and fosfomycin-rifampin. Daptomycin-rifampin cured 67% of cage-associated infections and fosfomycin-rifampin cured 83%, whereas all single drugs (fosfomycin, daptomycin, and tigecycline) and rifampin-free fosfomycin combinations showed no cure of MRSA cage-associated infections. No emergence of fosfomycin resistance was observed in animals; however, a 4-fold increase in fosfomycin MIC (from 2 to 16 μg/ml) occurred in the fosfomycin-vancomycin group. In summary, the highest eradication of MRSA cage-associated infections was achieved with fosfomycin in combination with rifampin (83%). Fosfomycin may be used in combination with rifampin against MRSA implant-associated infections, but it cannot replace rifampin as an antibiofilm agent.  相似文献   
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