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1.
Lung - Diaphragmatic paralysis (DP) is an important cause of dyspnea with many underlying etiologies; however, frequently no cause is identified despite extensive investigation. We hypothesized...  相似文献   
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Long-term daily use of gamma-hydroxybutyrate (GHB) and related compounds has recently been associated with a withdrawal syndrome. To the best of the authors' knowledge, there are currently no animal models of GHB withdrawal. OBJECTIVES: The authors studied and described the effect of chronic dosing of GHB (3-6 days) on tolerance and withdrawal in a rat model. METHODS: Rats were administered GHB every three hours via intraperitoneal catheter. Groups of rats (2 per group) were dosed with GHB for either 3 (24 doses), 4 (32 doses), 5 (40 doses), or 6 (48 doses) days. The GHB dose was 0.25 g/kg for doses 1-8, 0.75 g/kg for doses 9-12, 1 g/kg for doses 13-16, 1.25 g/kg for doses 17-24, 1.5 g/kg for doses 25-32, 1.75 g/kg for doses 33-40, and 2 g/kg for doses 41-48. Following the last dose of GHB, the rats were scored using a 16-point ethanol intoxication-withdrawal scale rating spontaneous behaviors, response to handling, grooming, and neurological signs. Lower scores indicate intoxication, while higher scores indicate withdrawal. Scores were recorded at hours 0, 1, 2, 3, 4, 5, 6, 9, 12, and 24. RESULTS: Tolerance: Rats dosed with GHB for more days were less intoxicated one hour after their last GHB dose despite receiving higher doses. WITHDRAWAL: The scores for all rats dosed with GHB increased at hours 4 (p = 0.028), 5 (p = 0.037), 6 (p = 0.007), and 9 (p = 0.024) after the last dose, indicating withdrawal. The scores demonstrated a linear increase dependent upon the number of days of GHB dosing at hours 3 (p < 0.000), 4 (p = 0.004), 5 (p = 0.002), and 12 (p = 0.039) as well as prior to the last dose at hour 0 (p = 0.000). No rats developed seizures. CONCLUSIONS: Tolerance and mild withdrawal in rats can be induced by administering intraperitoneal GHB every three hours for 3-6 days. More prolonged dosing and higher doses of GHB may be necessary to induce severe withdrawal.  相似文献   
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Sprague-Dawley rats with unilateral 6-OHDA substantia nigra lesions were given combined scopolamine (0.5 mg/kg IP) and apomorphine (0.05 mg/kg SC) treatments. In this animal model, scopolamine, when administered separately, induces ipsilateral rotation and apomorphine, contralateral rotation. When these drugs are co-administered at 0.5 mg/kg and 0.05 mg/kg dose levels, respectively, animals rotate in the contralateral direction, creating the opportunity for the stimulus effect of scopolamine to become associated with the response effect of apomorphine. In tests with scopolamine (0.5 mg/kg), animals that previously had scopolamine and apomorphine co-administered rotated contralaterally in the test chamber, thereby behaving as if they had received apomorphine. Thus, scopolamine exhibited a functionally acquired conditioned stimulus (CS) property by eliciting the apomorphine response of contralateral rotation as a conditioned response. This acquired CS property was extinguished with separate scopolamine trials and reacquired following one scopolamine-apomorphine co-administration trial.  相似文献   
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Immune modulation by heavy metals may cause serious adverse health effects in humans, although the mechanisms involved are not well understood. Both cadmium and lead are important environmental and occupational toxins. Therefore, in the current study, the costimulatory/adjuvant effects and the T-cell-activating potential of these metals (i.e., CdCl2 and PbCl2), are examined. These immune-modulating properties are critical in the development of conditions such as allergy, hypersensitivity, and autoimmunity. Using the direct popliteal lymph node assay (PLNA) and reporter antigen-popliteal lymph node assay (RA-PLNA) both metals were examined individually for immunotoxicity. Mercury (i.e., HgCl2) was included for comparative purposes as its effects in the RA-PLNA are well documented. Seven days following a single footpad injection containing metal and/or RA (trinitrophenyl-ovalbumin [TNP-OVA] or TNP-Ficoll), BALB/c mice were sacrificed and the popliteal lymph nodes (PLNs) removed. PLN cellularity, TNP-specific antibody-secreting cells (ASCs), and lymphocyte subsets were assessed. All three metals strongly stimulated T- and B-cell proliferation and ASC production following coinjection with the RA TNP-OVA. In each case, ASC production was skewed towards the IgG1 isotype. In addition, all three metals induced IgG production to TNP-Ficoll (although relatively weakly in the case of Cd). These results show that each of these metals can provide adjuvant signals to promote lymphocyte proliferation and enhance adaptive immune responses to unrelated antigens. Skewing of immune responses towards T helper type 2 responses suggests that each of these metals can enhance allergic and hypersensitivity reactions to environmental antigens. Furthermore, the induction of IgG responses to TNP-Ficoll, a T-cell-independent antigen, indicates that each of these metals can activate neoantigen-specific T cells. T-cell activation by metals can lead to metal hypersensitivity and has been implicated in the development of autoimmunity. This is the first report of immune modulation by CdCl2 and PbCl2 in the RA-PLNA.  相似文献   
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Many hospitals today have implemented widely disparate information systems on mainframe and mini-computer hardware. The advent of network technology in hospitals has made it possible to access information in these systems. Unfortunately, the user interfaces to applications on these systems are unique and difficult to learn, which makes them unsuitable for use by clinical services. In this paper we describe the development of a Physician's Workstation which integrates information from multiple existing information systems and discuss how the workstation makes it possible to move from the departmental systems of the present to the computer-based medical record system of the future.  相似文献   
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Several case reports have implicated Ginkgo biloba in clinically adverse bleeding disorders. Ginkgo biloba has been reported to increase pain-free walking distance among patients with peripheral artery disease (PAD). Standard PAD therapy includes 325 mg/day aspirin. The objective of this study was to examine potential adverse effects of concomitant aspirin and Ginkgo biloba on platelet function. Ginkgo biloba (EGb 761, 300 mg/day) was compared with placebo for effects on measures of platelet aggregation among adults consuming 325 mg/day aspirin in a randomized, double-blind, placebo-controlled, parallel design trial of 4-week duration. Participants were adults, age 69 +/- 10 years, with PAD or risk factors for cardiovascular disease. Outcome measures included platelet function analysis (PFA-100 analyzer) using ADP as an agonist (n = 26 placebo; n = 29 ginkgo), and platelet aggregation using ADP, epinephrine, collagen and ristocetin as agonists (n = 21 placebo; n = 23 ginkgo). Participants kept daily logs of bleeding or bruising episodes. There were no clinically or statistically significant differences between treatment groups for any agonists, for either PFA-100 analysis or platelet aggregation. Reports of bleeding or bruising were infrequent and similar for both study groups. In conclusion, in older adults with PAD or cardiovascular disease risk, a relatively high dose of Ginkgo biloba combined with 325 mg/day daily aspirin did not have a clinically or statistically detectable impact on indices of coagulation examined over 4 weeks, compared with the effect of aspirin alone. No adverse bleeding events were observed, although the trial was limited to a small sample size.  相似文献   
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It's all about sex: gender, lung development and lung disease.   总被引:1,自引:0,他引:1  
Accumulating evidence suggests that gender affects the incidence, susceptibility and severity of several lung diseases. Gender also influences lung development and physiology. Data from both human and animal studies indicate that sex hormones might contribute to disease pathogenesis or serve as protective factors, depending on the disease involved. In this review, the influence of gender and sex hormones on lung development and pathology will be discussed, with specific emphasis on pulmonary fibrosis, asthma and cancer.  相似文献   
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