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71.
Background: The carotid bulb has a high density of baroreceptors that play an important role in maintaining blood pressure. We hypothesized that atherosclerosis of the carotid bulb would reflect the severity of orthostatic hypotension more accurately than would atherosclerosis of other carotid artery segments.

Methods: This cross-sectional study included 198 non-diabetic adults. We measured the cardio-vascular ankle index as an index of arterial stiffness, intima-media thickness in each carotid artery segment (internal carotid artery, carotid bulb, distal and proximal portions, respectively, of the common carotid artery) as a measure of atherosclerosis, and heart rate variability as a measure of cardiac autonomic function. The sit-to-stand test was used to assess severity of orthostatic hypotension.

Results: Intima-media thickness of the carotid bulb was correlated with orthostatic systolic blood pressure change (r = ?0.218, p = 0.002), cardio-ankle vascular index (r = 0.365, p < 0.001) and heart rate variability parameters. Multivariate regression analysis revealed that among all of the segments, only intima-media thickness of the carotid bulb was an independent predictor of orthostatic systolic blood pressure change (p = 0.022).

Conclusion: Atherosclerosis of the carotid bulb was associated with severity of orthostatic hypotension, arterial stiffening and cardiac autonomic dysfunction than that of other carotid artery segments.  相似文献   

72.
The risk of vertical transmission of hepatitis C virus (HCV) from mother to infant has been well documented, but the exact mode of transmission is still unclear. In a set of monochorionic diamniotic monozygous twins, only the second baby was infected with HCV from the mother who was positive for serum HCV-RNA. The babies had an uncomplicated vaginal delivery 3 min apart and they were both bottle fed from the outset. The second baby developed clinical hepatitis that persisted to 30 months follow up. The intrauterine environment should have been identical for these twins, and therefore, the maternal HCV factors, including viral load are not the sole determining factors for mother-to-infant transmission of HCV.  相似文献   
73.
Two cases of recurrent pneumonia due to Chlamydia pneumoniae are described. C. pneumoniae was continuously detected from the nasopharynx in both patients by the polymerase chain reaction and/or culture even with appropriate antibiotic therapy during the first episode. After eradication of C. pneumoniae with long-term macrolide therapy, the respiratory symptoms of both patients completely disappeared and no relapse was observed. These data indicate that new treatment strategies may be necessary to eradicate the organism in patients prone to persistent infection.  相似文献   
74.
Interferon (IFN)-gamma reduces airway responses after allergen challenge in mice. The mechanisms of this effect are not clear. These studies investigate whether IFN-gamma can reverse prolonged airway responses after allergen challenge in IFN-gamma-deficient (IFN-gammaKO) mice. Sensitized mice (IFN-gammaKO and wild-type [WT]) were challenged with ovalbumin. Airway responsiveness, eosinophils in bronchoalveolar lavage fluid, and lung lymphocyte subsets (CD4(+) and CD8(+)) were measured 24 hours and 8 weeks after challenge. In further experiments, we treated IFN-gammaKO mice with recombinant IFN-gamma starting 4 weeks after the challenge for 1 week or 4 weeks. Airway responsiveness, bronchoalveolar lavage eosinophils, and lung CD4(+) cells were increased 8 weeks after challenge in IFN-gammaKO but not WT mice. IFN-gamma treatment returned lung CD4(+) cell numbers to values obtained in unchallenged mice. One week of IFN-gamma treatment also returned airway responsiveness to baseline levels; however, 4-week treatment with IFN-gamma failed to decrease airway responsiveness below levels observed in untreated animals. This suggests that IFN-gamma plays an essential role in reversing allergen-induced airway inflammation and hyperresponsiveness and that it may have dual actions on the latter. Observations that IFN-gamma reverses airway responses, even when administered after challenge, suggests that IFN-gamma treatment could control allergic disease, including asthma.  相似文献   
75.
To clarify the significance of newly appearing abnormal Q waves and their disappearance in patients with Kawasaki disease, regional myocardial perfusion and glucose metabolism at rest in the fasting condition were assessed by positron emission tomography (PET) with 13N-ammonia and 18F-fluorodeoxyglucose (FDG), and regional wall motion by left ventriculography in regions with persistent and transient abnormal Q waves in 14 patients. PET identified 3 groups of abnormal myocardial segments: segments with hypoperfusion without increased FDG uptake, those with hypoperfusion and increased FDG uptake, and those with normal perfusion and increased FDG uptake. Almost all the segments with persistent or transient abnormal Q waves had abnormal PET findings. PET demonstrated evidence of metabolic activity in 57% of segments with persistent abnormal Q waves and 67% of those with transient abnormal Q waves. Regional wall motion, scored from 0 (normal) to 4 (dyskinesia), was not significantly different between segments with persistent and transient abnormal Q waves (2.3 ± 1.3 vs 2.2 ± 1.2). The persistence of abnormal Q waves on serial electrocardiograms was significantly shorter in metabolically active than in inactive segments (19 ± 17 vs 92 ± 27 months). In conclusion, in patients with Kawasaki disease, the new appearance of abnormal Q waves is a reliable clue to the presence of ischemic myocardial injury and a high proportion of them are associated with metabolically active myocardial regions. The disappearance of abnormal Q waves does not necessarily mean the normalization of regional myocardial perfusion, metabolism or function, and their early disappearance may imply “viability” in the associated myocardial region.  相似文献   
76.
OBJECTIVE: The purpose of this study was to evaluate the prognostic and clinical significance of newly acquired complete right bundle branch block (CRBBB) in airline pilots. PATIENTS: This study included pilots with acquired CRBBB, identified from a group of over 2,700 Japan Airline pilots. When the pilots applied for employment, a past medical history, physical examination, electrocardiogram, and chest radiograph were obtained. The pilots with ECG abnormality including CRBBB were not included in the study because of hiring requirements. RESULTS: Thirty-six pilots with CRBBB were identified between 1983 and 2002. All pilots with CRBBB were evaluated for the presence of ischemic heart disease by treadmill exercise testing, echocardiogram and exercise thallium scintigraphy. Twelve individuals underwent coronary angiography. The mean age of pilots was 44.4 +/- 5.8 years. The mean observation period was 10.9 +/- 5.7 years. For each of the 36 study subjects, Holter electrocardiogram and echocardiogram were obtained every 6 months after the CRBBB was detected. Exercise stress testing was performed every year. Exercise thallium scintigraphy was performed every 2 years to detect ischemic heart disease. During the observation period, two pilots stopped flying temporarily because of frequent ventricular premature beats and one pilot stopped flying permanentaly because of atrial fibrillation. During the follow-up period, no cardiovascular events were observed in pilots with CRBBB who had no underlying ischemic heart disease. CONCLUSION: Acquired CRBBB does not confer a poor prognosis, particularly in young men working as a pilot if there is no evidence of ischemia on exercise stress testing, echocardiography and exercise thallium scintigraphy.  相似文献   
77.
A 66-year-old man with hepatocellular carcinoma (HCC) showed marked thrombocytosis (110.7 x 10(4)/microl). Bone marrow (BM) aspirates demonstrated an increase of mature megakaryocytes (MgK). The serum thrombopoietin (TPO) level was increased to about 100-fold that of the normal level in the terminal stage. However, the platelet count gradually decreased to 13.5 x 10(4)/microl. The autopsy specimen revealed normoplastic BM with decreased MgK, mainly consisting of the immature type, and it was negative for tumor cells. Liver specimen showed markedly fatty metamorphosis. Immunohistochemical staining of TPO demonstrated that hepatocytes were weakly stained and HCC cells strongly stained, suggesting TPO-producing HCC.  相似文献   
78.
This study aimed to evaluate the clinical use of choline-PET/CT for discriminating viable progressive osteoblastic bone metastasis from benign osteoblastic change induced by the treatment effect and evaluating the response of bone metastasis to treatment in metastatic castration-resistant prostate cancer (mCRPC) patients. Thirty patients with mCRPC underwent a total of 56 11C-choline-PET/CT scans for restaging, because 4 patients received 1 scan and 26 had 2 scans. Using 2 (pre- and post-treatment) 11C-choline-PET/CT examinations per patient, treatment response was assessed according to European Organization for Research and Treatment of Cancer (EORTC) criteria in 20 situations, in which only bony metastases were observed on 11C-choline-PET/CT scans. Viable bone metastases and osteoblastic change induced by the treatment effect were identified in 53 (94.6%) and 29 (51.8%) of 56 11C-choline-PET/CT scans, respectively. In 27 cases (48.2%), 11C-choline-PET/CT scans could discriminate the 2 entities. The mean SUVmax of the metastatic bony lesions was 5.82 ± 3.21, 5.95 ± 3.96, 6.73 ± 5.04, and 7.91 ± 3.25 for the osteoblastic, osteolytic, mixed, and invisible types, respectively. Of the 20 situations analyzed, CMR, PMR, SMD, and PMD, as determined by the EORTC, were seen in 1, 2, 3, and 14 cases, respectively. Of the 13 patients with increasing PSA trend, all 13 showed PMD. Of the 2 patients with PSA response of <50%, both 2 showed SMD. Of the 5 patients with PSA response of ≥50%, 1 showed CMR, 2 showed PMR, 1 showed SMD, and 1 showed PMD. Choline-PET/CT is very useful to discriminate viable progressive osteoblastic bone metastasis from osteoblastic change, and assess treatment response of bone metastases in mCRPC.  相似文献   
79.
Rationale:Anti-myelin oligodendrocyte protein antibody-associated disease (MOGAD) is a new disease entity with various clinical phenotypes. MOGAD often present with recurrent optic neuritis (ON), and it can also develop as a compartment of neuromyelitis optica spectrum disorder (NMOSD). Moreover, multiple autoantibodies such as an anti-myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) had been reported in the serum of patients with NMOSD.Patient concerns:We report an 86-year-old woman with a 2-year history of microscopic polyangiitis (MPA). The patient had a rapid loss of vision in her left eye. No abnormal findings were observed on her left fundus, and she tested negative for MPO-ANCA upon admission. However, anti-MOG antibodies were observed in the patient''s serum and cerebrospinal fluid.Diagnosis:A diagnosis of MOGAD complicated with MPA was made.Interventions:The patient received twice steroid pulse therapy and oral azathioprine as maintenance therapy.Outcomes:Her vision rapidly recovered, and no subsequent relapse was observed during the 8-month observation period.Conclusion:To the best of our knowledge, this is the first case of MOGAD complicated with MPA, and steroid pulse therapy and azathioprine therapy were effective for ON caused by MOGAD.  相似文献   
80.
Journal of Thrombosis and Thrombolysis - Prolonged anticoagulation therapy is recommended for patients with intermediate-risk for recurrence of venous thromboembolism (VTE). The current study aimed...  相似文献   
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