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91.
A recent HIV-1 molecular epidemiology survey in Singapore identified a novel CRF01_AE/B recombinant form, which accounted for 13 (11.9%) of 109 patient samples. Peripheral blood mononuclear cell DNA from three of these 13 patients was used to generate near full-length sequences to characterize the novel CRF01_AE/B recombinant form. The three isolates had a recombinant structure composed of CRF01_AE and subtype B, and shared identical breakpoints. As the three patients were not epidemiologically linked, this recombinant form has been designated CRF51_01B. Identification of the novel recombinant forms indicates ongoing active HIV-1 transmission in Singapore.  相似文献   
92.
PurposeIn this study, we aimed to investigate the possible association between SLC2A1 26177A/G polymorphism and diabetic retinopathy (DR) in Malaysian patients with type 2 diabetes.MethodsGenomic DNA was extracted from 211 Malaysian type 2 diabetic patients (100 without retinopathy [DNR], 111 with retinopathy) and 165 healthy controls. A high resolution melting assay developed in this study was used to detect SLC2A1 26177A/G polymorphism followed by statistical analysis.ResultsA statistically significant difference in 26177 G minor allele frequency between healthy controls (19.7 %) and total patient group (26.1 %) (p < 0.05, Odd ratio = 1.437, 95% Confidence interval = 1.015–2.035) as well as between healthy controls (19.7 %) and DNR patients (27.5%) (p < 0.05, Odd ratio = 1.546, 95% Confidence interval = 1.024–2.336) was shown in this study. However, when compared between DR and DNR patients, there was no significant difference (p > 0.05).ConclusionsThis is the first study which shows that SLC2A1 26177G allele is associated with type 2 diabetes in Malaysian population but not with DR.  相似文献   
93.
PurposeThe purpose of this study was to characterize macular microvasculature and structural retinal layers using magnification-corrected optical coherence tomography angiography (OCTA) images in children with amblyopia.MethodsThis prospective cross-sectional study included 22 children with unilateral amblyopia (4–11 years of age) receiving spectral-domain OCTA. Vessel densities in foveal and parafoveal regions of the superficial capillary plexus (SCP) and deep capillary plexus (DCP) were measured in amblyopic and fellow eyes using a customized image analysis program correcting the scale of retinal image with axial length. Iowa Reference Algorithms (Iowa Institute for Biomedical Imaging) were used to measure mean thickness values of 10 intra-retinal layers rescaled for image size correction.ResultsFoveal and parafoveal vessel densities in amblyopic eyes were lower than that of the fellow eyes in the SCP (fovea: P = 0.006 and parafovea: P = 0.003) and the DCP (P = 0.024 and P = 0.025, respectively). Amblyopic eyes had significantly smaller foveal avascular zone (FAZ) area than fellow eyes (P < 0.001). There were significant differences in retinal layer thickness between paired eyes, particularly in the inner retina in both foveal and parafoveal regions; retinal nerve fiber layer (RNFL) (P = 0.024 and P = 0.095, respectively), ganglion cell layer (P < 0.001 and P = 0.008), inner plexiform layer (IPL; P = 0.12 and P = 0.037), inner nuclear layer (P = 0.005 and P = 0.005), and outer plexiform layer (OPL; P = 0.02 and P = 0.057), except in the foveal IPL, the parafoveal RNFL, and OPL.ConclusionsUnilateral amblyopic eyes demonstrate reduced macular vessel density and thicker inner retinal layers compared with fellow eyes even after correcting for image magnification. Changes in macular microvasculature and structural layers may offer valuable insights in the development of amblyopia.  相似文献   
94.
Little information exists regarding the efficacy, modifiers, and outcomes of anemia management in children with CKD or ESRD. We assessed practices, effectors, and outcomes of anemia management in 1394 pediatric patients undergoing peritoneal dialysis (PD) who were prospectively followed in 30 countries. We noted that 25% of patients had hemoglobin levels below target (<10 g/dl or <9.5 g/dl in children older or younger than 2 years, respectively), with significant regional variation; levels were highest in North America and Europe and lowest in Asia and Turkey. Low hemoglobin levels were associated with low urine output, low serum albumin, high parathyroid hormone, high ferritin, and the use of bioincompatible PD fluid. Erythropoiesis-stimulating agents (ESAs) were prescribed to 92% of patients, and neither the type of ESA nor the dosing interval appeared to affect efficacy. The weekly ESA dose inversely correlated with age when scaled to weight but did not correlate with age when normalized to body surface area. ESA sensitivity was positively associated with residual diuresis and serum albumin and inversely associated with serum parathyroid hormone and ferritin. The prevalence of hypertension and left ventricular hypertrophy increased with the degree of anemia. Patient survival was positively associated with achieved hemoglobin and serum albumin and was inversely associated with ESA dose. In conclusion, control of anemia in children receiving long-term PD varies by region. ESA requirements are independent of age when dose is scaled to body surface area, and ESA resistance is associated with inflammation, fluid retention, and hyperparathyroidism. Anemia and high ESA dose requirements independently predict mortality.Almost three decades after the advent of recombinant erythropoietin, the management of renal anemia has become a recent focus of attention and changing paradigms. Whereas correction of hemoglobin (Hb) levels to near-normal has previously been recommended on the basis of association studies linking more severe anemia to morbidity and mortality with dialysis,13 interventional clinical trials consistently demonstrate that near-normalization of Hb increases the risk of vascular events and mortality in adults receiving maintenance hemodialysis and in those with CKD who are not undergoing dialysis.46 This has prompted ongoing reevaluation and revisions of treatment targets in patients exposed to erythropoiesis-stimulating agents (ESAs).7The appropriateness of applying treatment recommendations established in adult hemodialysis populations at high cardiovascular risk and adults with CKD to children undergoing dialysis is questionable because cardiovascular events are far less common in children with CKD. Furthermore, two thirds of children requiring dialysis initially opt for peritoneal dialysis (PD), and there are no systematic studies in the adult PD population to inform the optimal Hb target range in these patients. The risk profile of patients receiving PD may differ from that of the hemodialysis setting because of the absence of dialysis-induced intermittent hemoconcentration and lack of contact activation of the complement and coagulation systems.Further aspects to consider in pediatric anemia management are the greater physical activity of children and the need for optimal cognitive functioning at school.8,9 The significant physiologic variation of the normal Hb range with age10 and the relative ESA sensitivity that reportedly increases with age during early childhood are also noteworthy.11The registry of the International Pediatric Peritoneal Dialysis Network (IPPN) prospectively collects detailed clinical, biochemical, dialysis, and medication-related information (including ESA types and doses and modalities of iron supplementation) from a substantial number of children undergoing long-term PD around the world. In-depth analysis of this unique database has allowed us to (1) gain insight into the demographic characteristics of renal anemia and its treatment in the pediatric PD population worldwide, (2) explore the relationship between ESA dose requirements and body dimensions, (3) identify factors contributing to ESA resistance in children, and (4) associate anemia control with patient outcomes.  相似文献   
95.
96.

Background

The pancreas and peripancreatic region may be a site of metastasis from distant sites. Recent data suggest that pancreatic metastasectomy may achieve long-term survival. We seek to examine our experience with this metastasectomy by reporting the perioperative and survival outcomes.

Methods

Patients undergoing resection of isolated pancreatic metastasis were identified from a prospective pancreatic surgical database at the Department of Gastrointestinal Surgery, North Shore campus of the University of Sydney between January 2004 and June 2015 and selected for retrospective review. Data on operative morbidity and mortality were reported. Survival analysis was performed using the Kaplan–Meier method.

Results

Fifteen patients underwent pancreatic metastasectomy after a median disease-free interval of 63 months (range 0 to 199). Pancreatoduodenectomy was performed in six patients (40 %), distal pancreatectomy with or without splenectomy in three patients (20 %), and pancreatectomy with other visceral organ resection in six patients (40 %). Major complications occurred in six patients (40 %) without mortality. The median survival was 40 months (95 % CI 24.3 to 53.7), and 1-, 3-, and 5-year survival were 76, 48, and 31 % respectively. Cox proportional hazard model identified margin negative resection (hazard ratio (HR) 10.5; P?=?0.044) as a predictor of improved survival.

Conclusion

Long-term survival may be achieved in selected patients with pancreatic metastasis through pancreatic metastasectomy with acceptable morbidity. Selection of patients should be individualized and based on their primary disease origin, biological behavior of the tumor, resectability of the tumor, and the relative effectiveness of systemic or targeted therapies.
  相似文献   
97.

Background

This study aims to quantify changes in fibroblast growth factor 19 (FGF19) and bile acids (BAs) in patients with uncontrolled type 2 diabetes randomized to Roux-en-Y gastric bypass (RYGB) vs intensive medical management (IMM) and matched for similar reduction in HbA1c after 1 year of treatment.

Methods

Blood samples were drawn from patients who underwent a test meal challenge before and 1 year after IMM (n?=?15) or RYGB (n?=?15).

Results

Mean HbA1c decreased from 9.7 to 6.4 % after RYGB and from 9.1 to 6.1 % in the IMM group. At 12 months, the number of diabetes medications used per subject in the RYGB group (2.5?±?0.5) was less than in the IMM group (4.6?±?0.3). After RYGB, FGF19 increased in the fasted (93?±?15 to 152?±?19 pg/ml; P?=?0.008) and postprandial states (area under the curve (AUC), 10.8?±?1.9 to 23.4?±?4.1 pg?×?h/ml?×?103; P?=?0.006) but remained unchanged following IMM. BAs increased after RYGB (AUC ×103, 6.63?±?1.3 to 15.16?±?2.56 μM?×?h; P?=?0.003) and decreased after IMM (AUC ×103, 8.22?±?1.24 to 5.70?±?0.70; P?=?0.01). No changes were observed in the ratio of 12α-hydroxylated/non-12α-hyroxylated BAs. Following RYGB, FGF19 AUC correlated with BAs (r?=?0.54, P?=?0.04) and trended negatively with HbA1c (r?=??0.44; P?=?0.09); these associations were not observed after IMM.

Conclusions

BA and FGF19 levels increased after RYGB but not after IMM in subjects who achieved similar improvement in glycemic control. Further studies are necessary to determine whether these hormonal changes facilitate improved glucose homeostasis.
  相似文献   
98.
99.
Neutrophil elastase is a serine protease stored in the azurophilic granules of leukocytes. It has been implicated in the pathology of several lung diseases and is generally presumed to contribute to the tissue destruction and extracellular matrix damage associated with these conditions. To delineate the role of neutrophil elastase in pulmonary inflammation and fibrosis, neutrophil elastase-null mice were intratracheally instilled with bleomycin. In neutrophil elastase-null mice, biochemical and morphological characteristics of pulmonary fibrosis were attenuated for at least 60 days after bleomycin administration despite a typical response to bleomycin as evidenced by assessment of indices of DNA and cell damage. Neutrophil burden of bleomycin-treated wild-type and neutrophil elastase-null mice was comparable, and marked neutrophilic alveolitis was manifest in bleomycin-treated neutrophil elastase-null mice. An absence of immunostaining for active transforming growth factor (TGF)-beta in lung tissue from bleomycin-treated neutrophil elastase-null mice suggested a defect in TGF-beta activation, which was confirmed by biochemical assessment of TGF-beta levels in bronchoalveolar lavage fluid and lung tissue. These data point to novel and unexpected fibrogenic consequences of neutrophil elastase activity in the inflamed lung.  相似文献   
100.
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