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121.
122.
A multilaboratory study was conducted to develop a system for standardizing alanine aminotransferase (ALT) acceptability criteria ("cutoffs") for donated blood. Without standardized cutoffs, each laboratory must develop its own cutoff, and this may not make optimal use of ALT testing to reduce transmission of non-A, non-B hepatitis (NANB). Defining an ALT acceptability criterion in absolute terms is necessary because relative cutoffs based on local donor populations may be affected by the prevalence of NANB in each community. This study involved 16 laboratories using 23 different analytic systems. The ALT results of the analysis of a plasma reference sample could be used to translate mathematically a single, absolute cutoff to units applicable to each analytic system. The distribution of ALT results in 1.4 million donations from across the country was established; basing the cutoff on this sample avoids the problems inherent in using a local donor base to establish a cutoff. We propose the implementation of a system to standardize ALT acceptability criteria to an activity level defined by analysis of a nationwide donor sample.  相似文献   
123.
Background: Cancer patients undergo numerous invasive diagnostic procedures. However, there are only sparse data on the characteristics and determinants for procedure‐related pain among adult cancer patients. Methods: In this prospective study, we evaluated the characteristics and determinants of procedure‐related pain in 235 consecutive hematologic patients (M/F:126/109; median age 62 years, range 20–89 years) undergoing a bone marrow aspiration/biopsy (BMA) under local anesthesia. Questionnaires were used to assess patients before‐, 10 min and 1–7 days post BMA. Using logistic regression models, we calculated odds ratios (ORs) and 95% confidence intervals (CIs). Results: 165/235 (70%) patients reported pain during BMA; 92 (56%), 53 (32%) and 5 (3%) of these indicated moderate [visual analogue scale (VAS)≥30 mm], severe (VAS>54 mm) and worst possible pain (VAS=100 mm), respectively. On multivariate analyses, pre‐existing pain (OR=2.60 95% CI 1.26–5.36), anxiety about the diagnostic outcome of BMA (OR=3.17 95% CI 1.54–6.52), anxiety about needle‐insertion (OR=2.49 95% CI 1.22–5.10) and low employment status (sick‐leave/unemployed) (OR=3.14 95% CI 1.31–7.55) were independently associated with an increased risk of pain during BMA. At follow‐up 10 min after BMA, 40/235 (17%) patients reported pain. At 1, 3, 6 and 7 days post BMA, pain was present in 137 (64%), 90 (42%), 43 (20%) and 25 (12%) patients, respectively. Conclusions: We found that 3/4 of hematologic patients who underwent BMA reported procedural pain; one third of these patients indicated severe pain. Pre‐existing pain, anxiety about the diagnostic outcome of BMA or needle‐insertion, and low employment status were independent risk factors.  相似文献   
124.
Platelets have a central role in the development of arterial thrombosis and subsequent cardiovascular events. An appreciation of this complex process has made antiplatelet therapy the cornerstone of cardiovascular disease management. However, numerous patients will experience a recurrent atherothrombotic vascular event despite adequate antiplatelet therapy. Individual differences in the rate of platelet activation and reactivity markedly influence normal hemostasis and the pathological outcome of thrombosis. Such an individual variability is largely determined by environmental and genetic factors. These are known to either hamper platelets' response to agonists, and thereby mimic the pharmacological modulation of platelet function or mask therapy effect and sensitize platelets. In this article, we reviewed the antiplatelet mechanisms of aspirin and clopidogrel and the possible role of different polymorphisms, which may affect the efficacy of antiplatelet therapy. Heterogeneity in the way patients respond to aspirin and clopidogrel may in part reflect variation in cyclooxygenase (COX)-1, COX-2, glycoprotein (GP) Ib alpha, GP Ia/IIa, GP IIb/IIIa, UGT1A6*2, P2Y1, P2Y12, CYP2C9, CYP3A4 and CYP3A5 genotypes.  相似文献   
125.
126.

Background and purpose:

Indacaterol is a novel β2-adrenoceptor agonist in development for the treatment of chronic obstructive pulmonary disease. The aim of this study was to investigate the comparative pharmacology of indacaterol in recombinant cells expressing the common polymorphic variants of the human β2-adrenoceptor and in human primary airway smooth muscle (ASM) cells.

Experimental approach:

Chinese hamster ovarian-K1 cell lines expressing high and low levels of the common human β2-adrenoceptor variants were generated [Gly16-Glu27-Val34-Thr164(GEVT), RQVT, GQVT] and also the rare GQVI variant. Human primary ASM cells were isolated from explants of trachealis muscle. Adenosine-3′,5′-cyclic-monophosphate production was used as an outcome measure.

Key results:

In both the low- and high-expression recombinant GEVT ‘wild type’ cell lines indacaterol is a high-efficacy agonist. Salmeterol and formoterol were identified as low- and high-efficacy agonists, respectively, and showed similar potencies to indacaterol irrespective of the β2-adrenoceptor genotype. The I164 variant cell line was associated with a reduced capacity to generate adenosine-3′,5′-cyclic-monophosphate in response to β2-adrenoceptor agonist. In the human primary ASM cells indacaterol gave a maximal response intermediate between that of salmeterol and formoterol.

Conclusions and implications:

These data demonstrate that indacaterol is a high-efficacy agonist in recombinant cell systems but acts with lower efficacy in human primary ASM cells. No marked genotype-dependent effects were observed for common variants; however, changes in I164 receptor activity were identified, which were dependent on the level of expression of β2-adrenoceptors.  相似文献   
127.
A case of functional entrapment missed at the initial angiogram is presented. The imaging of popliteal artery entrapment syndrome and functional entrapment is discussed. The importance of appropriate imaging is emphasized. The classification of popliteal artery entrapment syndrome is discussed and it is proposed that functional entrapment is added to the existing classification in the interest of consistent reporting.  相似文献   
128.
Background Non‐ablative 1550‐nm erbium‐doped fractional photothermolysis systems (FPS) and 10 600‐nm carbon dioxide fractional laser systems (CO2 FS) have been effectively used to treat scars. Objective We compared the efficacy and safety of single‐session treatments of FPS and CO2 FS for acne scars through a randomized, split‐face, evaluator‐blinded study. Methods Eight patients with acne scars were enrolled in this study. Half of each subject’s face was treated with FPS and the other half was treated with CO2 FS. We used a quartile grading scale for evaluations. Results At 3 months after the treatment, the mean grade of improvement based on clinical assessment was 2.0 ± 0.5 for FPS and 2.5 ± 0.8 for CO2 FS. On each side treated by FPS and CO2 FS, the mean duration of post‐therapy crusting and scaling was 2.3 and 7.4 days respectively and that of post‐therapy erythema was 7.5 and 11.5 days respectively. The mean VAS pain score was 3.9 ± 2.0 with the FPS and 7.0 ± 2.0 with the CO2 FS. Conclusion We demonstrated the efficacy and safety of single‐session acne scar treatment using FPS and CO2 FS in East Asian patients. We believe that our study could be used as an essential reference when choosing laser modalities for scar treatment.  相似文献   
129.
Splenic lymphangiomatosis in children   总被引:14,自引:0,他引:14  
  相似文献   
130.
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