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81.
82.

Background

We investigated typical parameters of segmental mobility by means of accelerometry. The aim of this study was to collect first normal values for all movement segments of the spine.

Methods

The study involved 22 healthy young men. A mechanical impulse evoked a vibration wave in structures below the piston, and the vibration wave was registered by means of a piezoelectric sensor. Amplitude and wave duration were calculated for each of the tested segments.

Results

High amplitudes and short duration speak in favour of greater stiffness in the tested structures. Greater stiffness could be detected in the region of cervicothoracic transition and in the lower lumbar spine.

Discussion

The combined method of mechanical impulses and an accelerometer can provide objective parameters describing the stiffness and/or mobility of tested structures, which in our case were the segments of the spine. The influences of methodological variations are to be further investigated. The comparison of parameters from different segments could support diagnosis of pathological hypomobilities.  相似文献   
83.
OBJECTIVE: Ig molecules contain epitopes that can induce T cell-mediated immune responses. B cells can process and present such epitopes and activate T cells. The purpose of the present study was to test our hypothesis that T cells that recognize an Ig consensus sequence presented by B cells will modulate lupus-like disease in mice. METHODS: (NZB x NZW)F(1) (NZB/NZW) lupus mice received somatic B cell gene transfer of a DNA plasmid encoding a consensus sequence of T cell determinants of murine anti-DNA IgG or control plasmids. Treated animals were monitored for the production of antibody, the development of renal disease, and the phenotype, number, and function of T cells. RESULTS: Treatment of mice with Ig consensus plasmid induced transforming growth factor beta-producing CD8+,CD28- T cells that suppressed the antigen-specific stimulation of CD4+ T cells in a cell-contact-independent manner, reduced antibody production, retarded the development of nephritis, and improved survival. Significantly, adoptive transfer of CD8+,CD28- T cells from protected mice into hypergammaglobulinemic NZB/NZW mice effectively protected the transferred mice from the development of renal disease. CONCLUSION: Gene expression of anti-DNA Ig consensus sequence induces immunoregulatory T cells that delay the development of lupus nephritis by suppressing hypergammaglobulinemia and renal disease.  相似文献   
84.
Bacterial contamination is one of the potential risks of blood salvage and reinfusion during orthotopic liver transplantation (OLT) because cell-saver machines lack antibacterial protection devices. This study was designed to analyze the potential bacterial contamination of blood salvaged during OLT; a secondary end point was to evaluate whether reinfusion of potentially contaminated blood may have been responsible for clinically manifested infective complications in the same patient. After induction of anesthesia, a blood sample was drawn from the central venous catheter (CVC) immediately after its positioning, to exclude potential coexisting hematic contamination of the recipient. During the procedure, 2 other samples of salvaged blood were collected for bacteriological analysis. Twenty-six of 38 samples of salvaged blood were positive for microorganisms, whereas 12 did not reveal the presence of infectious agents. In 19 of 26 positive samples, Staphylococcus species (73%) were isolated with only 2 of 38 samples drawn from CVC being contaminated. Candida Albicans was cultured in 2 samples. The high percentage (73%) of coagulase-negative Staphylococci indicates that blood contamination could have been caused by microorganisms from the air or suctioned from contact surfaces and the surgical field. Although almost 70% of processed and reinfused units tested positive for microbes, none of the postoperative blood cultures (at day 1 and day 3) revealed growth of the same species, not even in the 2 patients who had positive CVC cultures after induction of anesthesia.  相似文献   
85.
Pharmacophore-based structural identification, synthesis, and structure-activity relationships of a new class of muscarinic M3 receptor antagonists, the diaryl imidazolidin-2-one derivatives, are described. The versatility of the discovered scaffold allowed for several structural modifications that resulted in the discovery of two distinct classes of compounds, specifically a class of tertiary amine derivatives (potentially useful for the treatment of overactive bladder by oral administration) and a class of quaternary ammonium salt derivatives (potentially useful for the treatment of respiratory diseases by the inhalation route of administration). In this paper, we describe the synthesis and biological activity of tertiary amine derivatives. For these compounds, selectivity for the M3 receptor toward the M2 receptor was crucial, because the M2 receptor subtype is mainly responsible for adverse systemic side effects of currently marketed muscarinic antagonists. Compound 50 showed the highest selectivity versus M2 receptor, with binding affinity for M3 receptor Ki = 4.8 nM and for M2 receptor Ki = 1141 nM. Functional in vitro studies on selected compounds confirmed the antagonist activity toward the M3 receptor and functional selectivity toward the M2 receptor.  相似文献   
86.
Sensitive skin syndrome was first described in 1977; however, no robust study has been carried out to evaluate its prevalence in Japan. A national representative sample of the Japanese population over the age of 18 years was taken. Individuals were questioned by telephone and selected according to the quota method. When asked “Do you have a sensitive skin?”, 52.84% of men and 55.98% of women answered “rather sensitive” or “very sensitive”. There was no significant difference (P = 0.22) between the two sexes. The non‐response rate among respondents was zero, suggesting that the term “sensitive skin” held a meaning for the majority of the population. Concerning questions about the onset of a rash, tingling or irritation in the presence of various factors, such as emotional issues, cold, heat, sun, dry air, air‐conditioning, water, air pollution and temperature variations, respondents with rather sensitive or very sensitive skin responded “yes” more often than others: approximately three‐times more often for water (18.97%/6.15%), air pollution (39.29%/12.45%) and warm climatic conditions (29.74%/9.8%). To our knowledge, this epidemiological study is the first to focus on sensitive skin among Japanese people of this century. It is of particular interest for two reasons: (i) it was conducted on a representative sample of the Japanese population; and (ii) the methodology used was identical to that used for sensitive skin assessment studies conducted in Europe and the USA, making it possible to draw certain comparisons.  相似文献   
87.
88.
Volatile anesthetics may cause vascular dysfunction; however, underlying effects are unclear. The aim of the present study was to investigate whether sevoflurane and isoflurane affect vascular function, nitric oxide (NO) bioavailability, and biomarkers of oxidative stress and inflammation. Wistar rats were divided into three experimental groups: Not anesthetized (control group) or submitted to anesthesia with isoflurane (Iso group) or sevoflurane (Sevo group). Hemodynamic parameters were monitored during anesthesia, and blood gas values and biochemical determinants were analyzed. Isometric contractions were recorded in aortic rings. Vasoconstriction induced by potassium chloride (KCl) and phenylephrine (Phe) were measured. No differences in hemodynamic parameters and blood gasses variables were observed. Impaired KCl and Phe-induced contractions were observed in endothelium-intact aorta of Sevo compared to Iso and Control groups. Redox imbalance was found in Sevo and Iso groups. Reduced NO bioavailability and increased activity of matrix metalloproteinase 2 (MMP-2) were observed in Sevo, but not in the Iso group. While reduced IL-10 and IL-1β were observed in Sevo, increases in IL-1β in the Iso group were found. Sevoflurane, but not isoflurane, anesthesia impairs vasocontraction, and reduced NO and cytokines and increased MMP-2 activity may be involved in vascular dysfunction after sevoflurane anesthesia.  相似文献   
89.
Splenectomy/asplenia is a condition associated with immune-compromission and specific vaccines are recommended for these patients, including the anti-COVID-19 vaccine. Among the high-risk group for which vaccination was prioritized in Italy, the immunocompromised patients after therapies or treatments were included. The Apulian regional archive of hospital discharge forms was used to define the list of splenectomized Apulian inhabitants, considering data from 2015 through 2020. The overall vaccination status of asplenic patients was assessed via data collected from the Regional Immunization Database. The history of SARS-CoV-2 infection and the infectious disease outcomes were extracted from the Italian Institute of Health platform “Integrated surveillance of COVID-19 cases in Italy”. 1219 Apulian splenectomized inhabitants were included; the incidence rate of SARS-CoV-2 infection was 15.0 per 100 persons-year with a proportion of re-infection equal to 6.4%; the proportion of hospitalization was 2.9%, with a case-fatality rate of 2.6%. The vaccine coverage (VC) for the anti-COVID-19 vaccine basal routine was 64.2%, for the first booster dose was 15.4%, and for the second booster dose was 0.6%. A multifactorial approach is needed to increase the vaccination uptake in this sub-group population and to increase the awareness of the asplenia-related risks to patients and health personnel.  相似文献   
90.
PURPOSE: The objective of this study was to compare the diagnostic quality of low-dose computed tomography (CT) with that of standard-dose chest CT in the diagnosis of infectious lung diseases. MATERIALS AND METHODS: Thirty chest CT scans [high-resolution computed tomography (HRCT), 15; spiral CT, 15] were performed in HIV-positive patients with an infectious lung disease. Two additional slices were obtained at two lower exposures (HRCT, 120 kV/70 mAs and 120 kV/50 mAs; spiral CT, 100 kV/56 mAs and 100 kV/40 mAs) after chest routine CT. Observers compared the quality of the images obtained at different parameters and image noise. Objective evaluation of image noise was also made. RESULTS: Diagnostic image quality was excellent in 93% of the low-dose HRCT scans and in 86% of the low-dose spiral CT scans, rates that are always acceptable in any case. Significant differences were found in noise levels between the low-dose and reference scans; however, artifacts did not compromise detection of abnormalities. In HRCT, a mean reduction of 77% from the standard technique to the low-dose scan is possible in total and in lung effective doses. In spiral CT, this reduction is lower at 71%. These values can reach a further reduction with ultra-low-dose imaging (84% in HRCT and 80% in spiral CT). CONCLUSIONS: Chest CT image quality appears to be adequate to evaluate pulmonary infectious diseases, even with an effective reduction in radiation dose. Standard-dose CT with a higher patient effective dose may be appropriate for selected cases.  相似文献   
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