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71.
Purpose

Sleep-disordered breathing is recognized as a comorbidity in patients with idiopathic pulmonary fibrosis (IPF). Among them, nocturnal hypoxemia has been reported to be associated with poor prognosis and disease progression. We developed a diagnostic algorithm to classify nocturnal desaturation from percutaneous oxygen saturation (SpO2) waveform patterns: sustained pattern, periodic pattern, and intermittent pattern. We then investigated the prevalence of nocturnal desaturation and the association between the waveform patterns of nocturnal desaturation and clinical findings of patients with IPF.

Methods

We prospectively enrolled patients with IPF from seven general hospitals between April 2017 and March 2020 and measured nocturnal SpO2 and nasal airflow by using a home sleep apnea test. An algorithm was used to classify the types of nocturnal desaturation. We evaluated the association between sleep or clinical parameters and each waveform pattern of nocturnal desaturation.

Results

Among 60 patients (47 men) who met the eligibility criteria, there were 3 cases with the sustained pattern, 49 cases with the periodic pattern, and 41 cases with the intermittent pattern. Lowest SpO2 during sleep and total sleep time spent with SpO2?<?90% were associated with the sustained pattern, and apnea–hypopnea index was associated with the intermittent pattern.

Conclusion

We demonstrated the prevalence of each waveform and association between each waveform and sleep parameters in patients with IPF. This classification algorithm may be useful to predict the degree of hypoxemia or the complication of obstructive sleep apnea.

  相似文献   
72.
Background: Patients with advanced hepatocellular carcinoma (HCC) need an effective treatment modality because of the poor prognosis of the disease. From an in vitro study, beta-interferon (IFN-beta) has been reported to enhance the antiproliferative effects of doxorubicin on HCC cell lines. In the present study, we investigated the therapeutic effects of combined IFN-beta and doxorubicin intra-arterial injection therapy on patients with advanced HCC. Methods: IFN-beta (3 MIU) and doxorubicin (10 mg/bodyweight) were given by one-shot intra-arterial injection through an arterial port to patients with advanced HCC. One treatment course consisted of three intra-arterial injections per week for 4 weeks. Three courses were conducted and evaluation was done monthly. Results: Eleven patients with advanced HCC were treated with combined IFN-beta and doxorubicin. One patient enteredcomplete remission (CR), seven patients were evaluated as having stable disease (SD) and three as having progressive disease (PD). The mean overall survival was 10 months. The mean survival for CR and SD patients was 15 months, and that for PD patients was 6 months (P = 0.0464, log-rank test). Decrease of serum total bilirubin was observed for all patients. Conclusion: Combined IFN-beta and doxorubicin intra-arterial therapy offers an effective chemotherapy option for patients with advanced HCC by improving liver function and having tolerable side-effects.  相似文献   
73.
The most serious problem in current gene therapy is discrepancies between experimental data and actual clinical outcomes, which may be due to insufficient analyses and/or inappropriate animal models. We have explored suicide gene therapy by using various clinically relevant animal models and doubt the clinical use of maximal suicide gene expression, which has been generally recommended. To explore this subject further, we studied what expression level of suicide gene and what promoter led to the maximal clinical benefit in the case of hepatic metastatic cancer in mice. Therapeutic and adverse side effects of 4 adenoviral vectors that express herpes simplex virus thymidine kinase (HSV-tk) under different promoters were scrupulously investigated in 2 mouse models of hepatic metastasis of gastric cancer that possess clinical characteristics. Surprisingly, increases in HSV-tk expression beyond a certain point, achieved by the Rous sarcoma virus long terminal repeat promoter, not only enhanced the adverse side effects of lethal hepatotoxicity and ganciclovir-independent cytotoxicity but also failed to further increase therapeutic potential. Moreover, the carcinoembryonic antigen (CEA) tumor-specific promoter, the therapeutic potential of which had been underestimated, was much more useful-even in the case of low CEA-producing cancer-than had been previously reported. In conclusion, the optimal therapeutic expression level of a suicide gene is a novel concept and a crucial factor for successful cancer gene therapy. The present results, which contradict those of previous studies, alert researchers about possible problems with ongoing and future clinical trials that lack this concept.  相似文献   
74.
Patent ductus venosus   总被引:1,自引:0,他引:1  
BACKGROUND: Patent ductus venosus is extremely rare with only 14 cases reported in the world literature. We present a case of patent ductus venosus. METHODS AND RESULTS: A 29-year-old male was admitted with melaena stool caused by gastric haemorrhagic ulcers. Laboratory data disclosed severe anaemia; however, liver function tests were normal. Serum ammonia was also within the normal range. Serological viral markers for hepatitis B or C were all negative. The abdominal ultrasonography and computed tomography indicated a 12 mm diameter shunt located in the left lobe of the liver, which connected the portal vein with the left hepatic vein. After treatment for gastric ulcers, percutaneous transhepatic portography was performed and an enormous shunt connecting the umbilical portion of the portal vein with the left hepatic vein was revealed. CONCLUSIONS: Histological findings of the liver biopsy showed that portal venules could not be observed in the portal areas and that no fibrosis or inflammatory cell infiltration were shown. Because of the anatomical position of the shunt, the case was diagnosed as patent ductus venosus.  相似文献   
75.
Abstract: Aims/Background: Activated liver macrophages in chronic hepatitis express a high affinity receptor for IgG named FcγRI. This study was performed to find the difference in FcγRI expression between chronic hepatitis B (CHB) and C (CHC) with reference to histological activity. Methods: Consecutive patients with CHB (20 cases) and CHC (25 cases) were enrolled in the study. Inflammatory activity was evaluated using the modified histological activity index (HAI). FcγRI-positive macrophages were quantitatively measured by computer assisted morphometry. Results: Total HAI score was significantly higher in CHB than in CHC. Confluent necrosis was observed in significantly higher frequency in CHB at Stages 3–5 than in CHC. The percentage area of FcγRI-positive macrophages was significantly higher in CHB than in CHC. In CHB, the percentage area of FcγRI-positive macrophages correlated with total HAI (< 0.01) as well as the degree of confluent necrosis (< 0.01), interface hepatitis (< 0.05) and portal inflammation (< 0.05). FcγRI-positive macrophages accumulated mainly at the site of confluent necrosis. In CHC, no correlation was observed between activated macrophages and any histological categories. Conclusion: These results suggest that FcγRI-positive macrophages are associated with confluent necrosis in CHB, which is more common in CHB patients than in CHC.  相似文献   
76.
Several experimental studies have suggested that the vasodilatory effects of calcium channel blockers (CCBs) are due in part to an endothelium-dependent mechanism. However, it remains unknown whether CCBs directly augment liberation of endothelium-derived dilator substances such as nitric oxide (NO) in the human vasculature. The aim of this study was to examine whether CCBs of several kinds directly increase the bioavailability of NO in forearm resistance vessels. Twenty-four healthy men (mean age 30 ± 2 years) were randomly assigned to three study groups (n = 8 in each), and each group was assigned one of three first-generation CCBs (nifedipine, nicardipine, diltiazem). Subdepressor doses of CCBs [4, 8, 16, 24, and 36 (diltiazem only) nmol/min; for 2 min in each dose] were infused intra-arterially, and forearm blood flow (FBF) was determined plethysmographically. After control FBF responses to CCBs had been measured, a NO synthase inhibitor (N G-monomethyl-l-arginine: l-NMMA) was infused intra-arterially, and the FBF response to CCBs was again determined. Further, as a positive control for NO stimulation, acetylcholine (ACh) was also examined before and after l-NMMA in each group. Systemic blood pressure and heart rate did not change significantly during the study protocol. The FBF responses to these CCBs did not differ before and after NO synthase inhibition by l-NMMA (FBF at maximum doses: nifedipine, 8.0 ± 0.8 vs 7.3 ± 0.7; nicardipine, 7.3 ± 1.5 vs 6.5 ± 1.3; diltiazem, 5.7 ± 0.7 vs 4.2 ± 0.7 ml/min per 100 ml: all not significant), although FBF responses to ACh were significantly reduced by l-NMMA. In conclusion, direct NO liberation does not make a significant contribution to the vasodilation associated with first-generation CCBs in healthy human resistance vessels. Received: July 12, 2001 / Accepted: October 19, 2001  相似文献   
77.
78.
We characterized 8 monoclonal antibodies (MAbs) to Karp, Kato, and Gilliam strains of Rickettsia tsutsugamushi, and analysed 17 isolates from patients with Tsutsugamushi disease using these MAbs. These were divided into 3 strain-specific (Kp/D11, Kt/2D9, and Gi/E4) and 5 cross-reactive MAbs (Kp/1F11, Kp/1C10, Kp/C6, Kt/3B2, and Kt/3C2). All MAbs recognized characteristic protein antigens using the indirect fluorescent-antibody test (IFA) and proteinase K treatment. Analysis by polyacrylamide gel electrophoresis and immunoblotting techniques revealed that Kato-specific MAb Kt/2D9 recognized a polypeptide with a molecular mass of 54 kilodalton (kDa) of the homologous strain, and cross-reactive MAbs Kp/1F11, Kp/C6, and Kt/3B2 recognized those of 46-47 kDa, 46-47 KDa, and 60 kDa, respectively to the homologous and heterologous strains. MAbs Kp/1C10 which exhibited a high IFA titer against the Karp strain and only low titers against heterologous strains recognized only the 110 kDa polypeptide of the homologous strain. MAb Kt/3C2 which reacted with both Karp and Kato strains recognized a 54 to 56 kDa polypeptide band of the two prototype strains as well as several other polypeptides, however, each molecular mass was present in only one of two strains. Testing by the plaque reduction technique showed another characteristic of MAb Kt/3C2 to neutralize both Karp and Kato Strains. Fourteen isolated strains from patients in the south and west regions of Gifu Prefecture, the Shimokoshi stain isolated in Niigata Prefecture, and Kawasaki and Kuroki stains isolated in Miyazaki Prefecture were examined for reactivities to 8 MAbs by IFA to classify their antigenicities. No isolated strains reacted with Karp-specific Kp/D11, Kato-specific Kt/2D9, or Gilliam-specific Gi/E4.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
79.
80.
Journal of Autism and Developmental Disorders - This study investigates the use of structural and discourse contextual cues in the interpretation of third-person pronouns by children and...  相似文献   
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