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951.
952.
OBJECTIVE: The hemodialysis (HD) team should deliver single-pool variable-volume (SPVV) urea Kt/V>or=1.2. At present dialysis machines provide online assessment of Kt/V. The aim of our study is to assess if online Kt/V and SPVV urea Kt/V yield similar values and if it may be replaced in evaluation of HD adequacy. PATIENTS AND METHODS: Studies were carried out two times (evaluation I and evaluation II) in 40 patients dialyzed using machines with online Kt/V monitoring by the conductivity method. During the middle HD session in the week, SPVV Kt/V was estimated from urea measurements in serum at the beginning and at the end of the HD session using the second generation formula of Daugirdas. Values of SPVV urea Kt/V and simultaneously obtained online Kt/V were compared. RESULTS: In I, SPVV Kt/V was 1.37+/-0.16, and online Kt/V was 1.16+/-0.14 (P=0.000), r=0.559 (P=0.000); a regression equation indicated SPVV Kt/V as 0.62457+0.64048 * online Kt/V. In II, estimated SPVV Kt/V was 1.37+/-0.20, online Kt/V-1.16+/-0.15 (P=0.000), r=0.493 (P=0.001), and calculated SPVV Kt/V was 1.37+/-0.10. In I, SPVV urea Kt/V>1.20 was shown in 87.5% of patients, whereas online Kt/V>1.20 was observed in 37.5% of cases (P=0.000). In II, respective values were 82.5% and 40.0% of patients (P=0.000). CONCLUSIONS: SPVV urea Kt/V indicates a more adequate HD session than online Kt/V. This difference has to be considered when applying Kt/V to clinical practice.  相似文献   
953.
Shiga toxin-producing Escherichia coli (STEC) is a group of pathogenic strains responsible for bloody diarrhea and hemorrhagic colitis, with often severe complications. Shiga toxins are the main factors causing the phathogenicity of STEC. Production of these toxins depends on the presence of stx1 and stx2 genes, which are located on lambdoid prophages, and their expression is stimulated upon prophage induction. Therefore, a transition of the phage genome from the prophage state to an extrachromosomal genetic element, and its further propagation, is crucial for the pathogenic effects. However, our knowledge on specific conditions for induction of these prophages in bacteria occurring in human intestine is very limited. In this report we present results of our studies on five different phages, originally occurring in STEC strains, in comparison to bacteriophage lambda. We found that efficiencies of induction of prophages and their further development vary considerably in response to different induction agents. Moreover, efficiency of progeny phage production might be modulated by other factors, like temperature or bacterial growth rate. Therefore, it is likely that pathogenicity of different STEC strains may be significantly different under specific conditions in their natural habitats.  相似文献   
954.
Background and aims  The purpose of this study was to determine the utility of bilateral internal jugular venous sampling with rapid parathyroid hormone assay (BIJV–IOPTH) in comparison to endocrine surgeon-performed ultrasonography of the neck as an alternative localizing modality in guiding patients with primary hyperparathyroidism (pHPT) and negative sestamibi scans for minimally invasive parathyroidectomy (MIP). Patients and methods  Seventy eight consenting patients with a negative subtraction sestamibi scan planned for parathyroidectomy underwent additional ultrasound parathyroid imaging and were randomized to undergo surgery without vs. with additional BIJV–IOPTH; n = 39 in each group. The patients with a positive alternative imaging test were qualified for video-assisted MIP, whereas the others underwent open neck explorations. The primary outcome measure was the number of patients with true-positive results of alternative imaging tests. Results  Of the 78 patients, 50 (64%) had a single adenoma, eight (10.3%) had double adenomas, and 20 (25.7%) demonstrated four-gland hyperplasia. Ultrasonography alone vs. combined with BIJV–IOPTH was true positive in detecting a solitary parathyroid adenoma in 8/24 (33.3%) vs. 17/26 (65.4%) patients, respectively (p = 0.023). Curative video-assisted MIP was successfully performed in all the patients with true-positive results. The remaining individuals were cured by more extensive open neck explorations (unilateral—4/39 vs. 4/39, respectively; p = 1.0 or bilateral—27/39 vs. 18/39, respectively; p = 0.039). Conclusions  Most patients with pHPT and a negative subtraction sestamibi scan (64%) have a single adenoma. BIJV–IOPTH as an addition to a surgeon-performed ultrasound of the neck allows for more accurate guiding for MIP in patients with a solitary parathyroid adenoma and negative subtraction sestamibi scans. Presented at the 3rd Workshop of the European Society of Endocrine Surgeons (ESES), “Modern techniques in primary hyperparathyroidism surgery: An evidence based perspective”, 19-21 of March 2009, Lund, Sweden. “Best of Endocrine Surgery in Europe 2009”  相似文献   
955.
BACKGROUND & AIMS: It has been hypothesized that dietary factors involved in methyl group metabolism, such as methionine, folate, and vitamin B(6), may modify cancer risk. We have previously reported an inverse association between folate intake and pancreatic cancer risk in a prospective population-based cohort of Swedish women and men. In the present study, we used data from this prospective study to examine whether methionine and vitamin B(6) intakes were associated with the incidence of exocrine pancreatic cancer. METHODS: Our study population comprised 81,922 Swedish women and men, aged 45-83 years, who were free from cancer and completed a self-administered food-frequency questionnaire in 1997. We used Cox proportional hazards models to estimate rate ratios with 95% confidence intervals (CI), adjusted for age, sex, education, smoking, body mass index, diabetes, and intakes of total energy and dietary folate. RESULTS: During a mean follow-up of 7.2 years, through June 2005, 147 incident cases of pancreatic cancer were diagnosed. Methionine intake was significantly inversely associated with risk of pancreatic cancer, whereas no significant association was observed for dietary or total vitamin B(6) intake. The multivariate rate ratios comparing the highest with the lowest quartile of methionine intake were 0.44 (95% CI, 0.26-0.73; P for trend = .0005) in women and men combined, 0.59 (95% CI, 0.28-1.21; P for trend = .07) in women, and 0.32 (95% CI, 0.15-0.65; P for trend = .002) in men. CONCLUSIONS: These findings suggest that higher methionine intake may reduce the risk of pancreatic cancer.  相似文献   
956.
957.
Ibritumomab, an (90)Yttrium ((90)Y) labelled radioimmunoconjugate, is registered in Europe to treat follicular lymphomas. Its mode of action combines the selectivity of monoclonal antibodies with the efficiency of radiotherapy, making it a unique and useful therapeutic agent. This paper is for haemato-oncologists with a decent practice in lymphoma therapy, who have not yet used ibritumomab themselves. It summarizes clinical trials with radioimmunotherapy, indicating clinical situations where it may be specifically useful.  相似文献   
958.
959.
Osteocalcin is the most important noncollagenous protein component of the bone. Polymorphisms of osteocalcin gene were reported to be associated with bone mineral density. However, this relation was only confirmed in some populations. In this study presence of C/T polymorphism in osteocalcin gene (rs1800247) was determined in Kashubian population (northern Poland). The frequencies of variants were CC 9 %, TC 31 %, and TT 60 %, with no significant differences between genders. The genotypes were in Hardy–Weinberg equilibrium.  相似文献   
960.
The heart is the rarest site for neoplasms to be localized. Despite modern diagnostic techniques, cardiac tumours continue to among those discovered latest and with the worst prognoses. We present the case of a 62-year-old woman with a heart tumour and mediastinal lymphadenopathy, who was admitted to the Department of Cardiac Surgery. The patient underwent surgical removal of the tumour with extracorporeal circulation. The left atrium, mitral valve and the left ventricle were occupied by the infiltration. A radical resection appeared to be impossible. A valvular prosthesis was not implanted. The perioperative period was uncomplicated. On the 9th day a local recurrence was confirmed in the transthoracic echocardiography. Further oncological diagnostics revealed the spread of the malignant neoplasm to bones of the pelvis and spine. Chemotherapy was initiated. The authors discuss the most appropriate diagnostic and treatment procedures employed in the above case.  相似文献   
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