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101.
Manten GT Franx A Sikkema JM Hameeteman TM Visser GH de Groot PG Voorbij HA 《Thrombosis research》2004,114(1):19-23
INTRODUCTION: Pregnancy has recently been described as a generalized intravascular inflammatory response to the conceptus. Total fibrinogen concentrations increase during pregnancy. The percentage high molecular weight fibrinogen (HMW-Fg) of the concentration total fibrinogen is known to increase during acute-phase conditions like inflammation. Therefore, we investigated whether the percentage high molecular weight fibrinogen increases during normal pregnancy. MATERIALS AND METHODS: Eighteen healthy nulliparous women with uncomplicated pregnancies with normal course and outcome participated in this study. Five blood samples were drawn from every woman in the gestational age periods 9 to 16, 17 to 24, 25 to 33 and 34 to 42 weeks and at 12 to 20 weeks after delivery. Total fibrinogen concentrations were determined according to Clauss and the percentage high molecular weight fibrinogen was assessed by SDS-electrophoresis and densitometry after isolation of fibrinogen by precipitation. One-way analysis of variance (ANOVA) was used to evaluate differences between gestational age periods and correlation coefficients were calculated by Pearson's method. RESULTS: Total fibrinogen concentrations increased with advancing gestational age and decreased after delivery. The percentage high molecular weight fibrinogen of the total fibrinogen remained unaltered during and after pregnancy. CONCLUSIONS: During normal pregnancy, there is an increase of total fibrinogen concentrations with advancing gestational age, without a rise in percentage high molecular weight fibrinogen. After delivery, the total fibrinogen returns to baseline concentrations. 相似文献
102.
Wanten G Kusters A van Emst-de Vries SE Tool A Roos D Naber T Willems P 《Clinical nutrition (Edinburgh, Scotland)》2004,23(4):623-630
BACKGROUND & METHODS: Total parenteral nutrition is frequently used in clinical practice to improve the nutritional status of patients. However, the risk for infectious complications remains a drawback in which immune-modulating effects of the lipid component may play a role. To characterize these lipid effects we investigated neutrophil activation by opsonized yeast particles under influence of lipid emulsions derived from fish oil (VLCT), olive oil (LCT-MUFA), soybean oil (LCT), and a physical mixture of coconut and soybean oil (LCT-MCT). RESULTS: Serum-treated zymosan (STZ) evoked a biphasic increase in cytosolic Ca2+ concentration ([Ca2+]c) with an initial slow rise that turned into a second fast rise until a plateau was reached. LCT-MCT (5 mM) pretreatment markedly increased the rate of [Ca2+]c rise during the initial phase, abolished the second phase and lowered the plateau. These effects of LCT-MCT were mimicked by the protein kinase C (PKC) activating phorbol ester PMA. LCT, LCT-MUFA and VLCT, on the other hand, decreased the rate of [Ca2+]c rise during both phases and lowered the plateau. The platelet-activating factor (PAF) receptor antagonist WEB 2086 inhibited the second phase, demonstrating that PAF acts as an intercellular messenger in STZ-induced Ca2+ mobilization, but did not interfere with the stimulatory effect of LCT-MCT or PMA on the initial rate of [Ca2+]c rise. CONCLUSIONS: Structurally different lipids act only in part through PAF to distinctively modulate neutrophil calcium signaling in response to activation by opsonized particles. 相似文献
103.
den Broeder AA Wanten GJ Oyen WJ Naber T van Riel PL Barrera P 《The Journal of rheumatology》2003,30(2):232-237
OBJECTIVE: To evaluate the effects of therapy with a fully human anti-tumor necrosis factor (TNF)-alpha monoclonal antibody on the production of superoxide and other reactive oxygen species (ROS) and on the migration capacity of neutrophils in patients with rheumatoid arthritis (RA). METHODS: A total of 29 patients with active RA and 25 healthy controls participated. Assessments were performed at baseline and 2 weeks after the first administration of anti-TNF-alpha. The production of ROS was studied in unstimulated conditions and after stimulation of receptor dependent (serum treated zymosan, STZ) and receptor independent (phorbol mystrate acetate, PMA) pathways by luminol enhanced chemiluminescence. As well, the PMA induced burst production of superoxide was measured using the cytochrome-c reduction assay. Potential changes in neutrophil migration to joints were assessed by scintigraphy with autologous leukocytes. RESULTS: Baseline production of ROS (both spontaneously and after STZ stimulation) and superoxide and the ex vivo chemotaxis were similar in RA patients (n = 25) and controls (n = 25) and remained unchanged after administration of anti-TNF-alpha. The production of ROS after PMA stimulation was slightly higher in patients than in controls (p = 0.04) and this difference disappeared 2 weeks after the first dose of anti-TNF-alpha (p < 0.05). The scintigraphic study showed that a single dose of anti-TNF-alpha, but not placebo, markedly decreased the influx of leukocytes to inflamed joints. CONCLUSION: In patients with RA, anti-TNF-alpha therapy rapidly decreases the influx of leukocytes into inflamed joints but does not impair neutrophil chemotaxis and production of ROS. 相似文献
104.
A novel mutation of M1S1 gene found in a Vietnamese patient with gelatinous droplike corneal dystrophy 总被引:2,自引:0,他引:2
Ha NT Chau HM Cung le X Thanh TK Fujiki K Murakami A Kanai A 《American journal of ophthalmology》2003,135(3):390-393
To identify the genetic defect in the M1S1 gene responsible for gelatinous droplike corneal dystrophy (GDLD) in a Vietnamese family.Experimental study.Blood samples were collected from a patient and the unaffected members of a GDLD-affected family. Fifty normal unrelated subjects of Vietnamese origin were used as controls. Genomic DNA was extracted from blood leukocytes. DNA analysis of the M1S1 gene was performed using polymerase chain reaction and direct sequencing.Sequencing of the M1S1 gene revealed a deletion of a 12-base-pair (bp) fragment from nucleotide positions 772 to 783 [772 to 783del(ATCTATTACCTG)], resulting in a loss of four amino acids at codons 258 to 261 (L258-liter261del). Yet, an insertion of nucleotide T in place of the missing sequence (772insT) was found. This combined mutation was homozygous in the GDLD-affected patient and heterozygous in his unaffected son and younger sister. Such genetic alteration was excluded in the control population.This is the first report of a mutational analysis performed in a Vietnamese patient with GDLD. In this family, the novel 772 to 783del(ATCTATTACCTG) + 772insT mutation on the M1S1 gene was well cosegregated with the phenotype and thus expected to cause GDLD. Although the M1S1 gene was responsible for GDLD in Vietnamese patients, the mutation found here is completely different from that previously reported in Japanese patients, where GDLD is most frequently seen. 相似文献
105.
Miles MV Tang PH Glauser TA Ryan MA Grim SA Strawsburg RH deGrauw TJ Baumann RJ 《Pediatric neurology》2003,29(2):143-147
This study examines the relationship between serum and saliva topiramate concentrations, and attempts to determine if saliva may be a useful alternative to serum for therapeutic monitoring. Saliva and blood specimens were collected from 31 epilepsy patients (mean age 10.5 +/- 6.0 years; range 2.5 years to 24.8 years), and topiramate concentrations were determined by fluorescence polarization immunoassay. One patient's results were omitted because the saliva concentration was below the limit of quantitation of the assay. A strong correlation exists between serum and saliva topiramate concentrations (adjusted r(2) = 0.97, n = 30, P < 0.0001). The mean fraction of saliva to serum concentration is 89.8% +/- 12.1% (range 62.9% to 112.7%). The results of this study support the use of saliva as a viable alternative to serum for monitoring topiramate therapy. Topiramate concentration in saliva: an alternative to serum monitoring. 相似文献
106.
Miles MV Horn PS Morrison JA Tang PH DeGrauw T Pesce AJ 《Clinica chimica acta; international journal of clinical chemistry》2003,332(1-2):123-132
BACKGROUND: Abnormal concentrations of coenzyme Q(10) have been reported in many patient groups, including certain cardiovascular, neurological, hematological, neoplastic, renal, and metabolic diseases. However, controls in these studies are often limited in number, poorly screened, and inadequately evaluated statistically. The purpose of this study is to determine the reference intervals of plasma concentrations of ubiquinone-10, ubiquinol-10, and total coenzyme Q(10) for self-reported healthy adults. METHODS: Adults (n=148), who were participants in the Princeton Prevalence Follow-up Study, were identified as healthy by questionnaire. Lipid profiles, ubiquinone-10, ubiquinol-10, and total coenzyme Q(10) concentrations were measured in plasma. The method used to determine the reference intervals is a procedure incorporating outlier detection followed by robust point estimates of the appropriate quantiles. RESULTS: Significant differences between males and females were present for ubiquinol-10 and total coenzyme Q(10). Blacks had significantly higher Q(10) measures than whites in all cases except for the ubiquinol-10/total Q(10) fraction. CONCLUSIONS: The fraction of ubiquinol-10/total coenzyme Q(10) is a tightly regulated measure in self-reported healthy adults, and is independent of sex and racial differences. Different reference intervals for certain coenzyme Q(10) measures may need to be established based upon sex and racial characteristics. 相似文献
107.
Marc P. van der Schroeff Kim van Schie Ton P. M. Langeveld Caspar Looman Robert J. Baatenburg de Jong 《European archives of oto-rhino-laryngology》2010,267(9):1445-1448
Dedicated software packages incorporating prognostic models are meant to aid physicians in making accurate predictions of prognosis. This study concerns 742 predictions of 5-year survival on consecutive newly diagnosed patients with head- and neck squamous cell carcinoma. The 5-year survival predictions made by the physicians are not compared with actual survival, but with a prediction made by OncologIQ, a dedicated software package. We used a linear regression and a linear mixed-effects model to look at absolute differences between both predictions and possible learning effects. Predictions made by the physicians were optimistic and inaccurate. Using the linear regression and linear mixed-effects models, the physicians’ learning effect showed little improvement per successive prediction. We conclude that prognostic predictions in general are imprecise. When given feedback on the model’s predicted survival, the accuracy increases, but only very modestly. 相似文献
108.
Vesico-ureteric reflux: occurrence and long-term risks 总被引:1,自引:0,他引:1
The prevalence of vesico-ureteric reflux in the general population is unknown, but it is increased in risk groups, such as children with symptomatic urinary tract infection, schoolgirls with asymptomatic bacteriuria, first-degree relatives of patients with reflux and children with prenatal dilatation of their upper urinary tract. Children and adults with pyelonephritic renal scarring are at risk of serious long-term complications, e.g. hypertension and renal failure. Modern paediatric care, with early detection and treatment of urinary tract infections and reflux during childhood and adolescence, may improve long-term prognosis. In the adult patient with established pyelonephritic renal scarring, careful control of hypertension may retard the rate of progression, and angiotensin converting enzyme inhibitors may have renal protective properties. 相似文献
109.
Preservation of beta-cell function by targeting beta-cell mass 总被引:1,自引:0,他引:1
Type 2 diabetes is characterized by progressive beta-cell dysfunction and a reduction in beta-cell mass. Pancreatic islets are a target for adverse effectors such as high concentrations of glucose, pro-inflammatory cytokines and increased free fatty acid concentrations - which are associated with adiposity, insulin resistance and the induction of beta-cell apoptosis. If the beta-cell mass is already below the threshold for maintaining normoglycemia, the expansion of beta-cell mass is the only option for achieving normoglycemia without the use of additional glucose-lowering agents. Therapies based on glucagon-like peptide-1 and combinations of growth factors such as epidermal growth factor and gastrin are promising new strategies for beta-cell preservation. In this review, we address the mechanisms involved in beta-cell dysfunction and beta-cell loss, and provide a rationale for pharmacological intervention for the preservation and/or expansion of beta-cell mass in type 2 diabetes. 相似文献
110.
Esther Meesterberends Ruud J.G. Halfens Marieke D. Spreeuwenberg Ton A.W. Ambergen Christa Lohrmann Jacques C.L. Neyens Jos M.G.A. Schols 《Journal of the American Medical Directors Association》2013,14(8):605-610
ObjectivesTo investigate whether the incidence of pressure ulcers in nursing homes in the Netherlands and Germany differs and, if so, to identify resident-related risk factors, nursing-related interventions, and structural factors associated with pressure ulcer development in nursing home residents.DesignA prospective multicenter cohort study.SettingTen nursing homes in the Netherlands and 11 nursing homes in Germany (around Berlin and Brandenburg).ParticipantsA total of 547 newly admitted nursing home residents, of which 240 were Dutch and 307 were German. Residents had an expected length of stay of 12 weeks or longer.MeasurementsData were collected for each resident over a 12-week period and included resident characteristics (eg, demographics, medical history, Braden scale scores, nutritional factors), pressure ulcer prevention and treatment characteristics, staffing ratios and other structural nursing home characteristics, and outcome (pressure ulcer development during the study). Data were obtained by trained research assistants.ResultsA significantly higher pressure ulcer incidence rate was found for the Dutch nursing homes (33.3%) compared with the German nursing homes (14.3%). Six factors that explain the difference in pressure ulcer incidence rates were identified: dementia, analgesics use, the use of transfer aids, repositioning the residents, the availability of a tissue viability nurse on the ward, and regular internal quality controls in the nursing home.ConclusionThe pressure ulcer incidence was significantly higher in Dutch nursing homes than in German nursing homes. Factors related to residents, nursing care and structure explain this difference in incidence rates. Continuous attention to pressure ulcer care is important for all health care settings and countries, but Dutch nursing homes especially should pay more attention to repositioning residents, the necessity and correct use of transfer aids, the necessity of analgesics use, the tasks of the tissue viability nurse, and the performance of regular internal quality controls. 相似文献