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61.
Sokic-Milutinovic A Todorovic V Milosavljevic T Micev M Drndarevic N Mitrovic O 《World journal of gastroenterology : WJG》2005,11(27):4140-4147
ABM: To assess long-term effects of Helicobacter pylori (H pylori) eradication on antral G cell morphology and function in patients with and without duodenal ulcer (DU). METHODS: Consecutive dyspeptic patients referred to the endoscopy entered the study. Out of 39 H pylori positive patients, 8 had DU (Hpylori+DU) and 31 gastritis (Hpylori +G). Control groups consisted of 11 uninfected dyspeptic patients (CG1) and 7 healthy volunteers (CG2). Basal plasma gastrin (PGL), antral tissue gastrin concentrations (ATGC), immunohistochemical and electron microscopic characteristics of G cells were determined, prior to and 6 mo after therapy. RESULTS: We demonstrated elevated PGL in infected patients compared to uninfected controls prior to therapy. Elevated PGL were registered in all H pylori+patients (H pylori +DU: 106.78±22.72 pg/mL, H pylori+G: 74.95±15.63, CG1: 68.59±17.97, CG2: 39.24±5.59 pg/mL, P<0.01). Successful eradication (e) therapy in H pylori+patients lead to significant decrease in PGL (H pylori+DU:59.93±9.40 and H pylori+Ge: 42.36±10.28 pg/mL, P<0.001). ATGC at the beginning of the study were similar in infected and uninfected patients and eradication therapy lead to significant decrease in ATGC in H pylori+gastritis, but not in DU patients. In the H pylori+DU patients, the mean number of antral G cells was significantly lower in comparison with all other groups (P<0.01), but after successful eradication was close to normal values found in controls. By contrast, G cell number and volume density were significantly decreased (P<0.01) in H pylori+Ge group after successful eradication therapy (294±32 and 0.31±0.02, respectively), in comparison to values before eradication (416±40 and 0.48±0.09). No significant change of the G cell/total endocrine cell ratio was observed during the 6 mo of follow up in any of the groups. A reversible increase in G cell secretory function was seen in all infected individuals, demonstrated by a more prominent secretory apparatus. However, differences between DU and gastritis group were identified. CONCLUSION: H pylori infection induces antral G cell hyperfunction resulting in increased gastrin synthesis and secretion. After eradication therapy complete morphological and functional recovery is observed in patients with gastritis. In the DU patients some other factors unrelated to the H pylori infection influence antral G cell morphology and function. 相似文献
62.
Anna Duda-Sobczak Bogusz Falkowski Aleksandra Araszkiewicz Dorota Zozulinska-Ziolkiewicz 《Clinical therapeutics》2018,40(6):872-880
Purpose
The accumulation of advanced glycation end products (AGEs) in local tissue is an important cause of low-grade inflammation and oxidative stress and is linked to late diabetic complications. Physical activity has various beneficial cardiometabolic effects in type 1 diabetes (T1D) and is associated with lower frequency of chronic complications of diabetes, although the specific mechanisms still remain unclear. The present study determines the association between self-reported physical activity and skin autofluorescence (AF), a marker of tissue accumulation of AGEs in adults with T1D.Methods
We enrolled 119 patients (63 women), aged 34 years (interquartile range [IQR], 26–41 years), with T1D duration of 17 years (IQR, 12–25 years), glycosylated hemoglobin (HbA1c) of 7.9% (IQR, 7.1%–8.9%) referred to an outpatient diabetes clinic. Patients with diabetes duration of <5 years, age >65 years, concomitant diabetic ketoacidosis, and severe complications that restrict physical activity (eg, diabetic foot, diabetic proliferative retinopathy, blindness) were excluded. Physical activity was measured with the short version of the International Physical Activity Questionnaire (IPAQ-SF), and raw scores were then log-transformed because of non-normality. The accumulation of AGEs in the skin was assessed on the basis of skin AF. Correlations between AF and various laboratory and clinical findings were assessed, and multivariate linear regression analysis was used to examine factors that influenced AGEs.Findings
Skin AF correlated positively with age (Spearman’s coefficient [Rs] = 0.47; P < 0.0001), HbA1c (Rs = 0.30; P = 0.001), waist-to-hip ratio (WHR; Rs = 0.23; P = 0.02), and negatively with logIPAQ-SF (Rs = –0.28; P = 0.002). A stepwise multivariable linear regression analysis indicated age (β = 0.46; P < 0.0001), HbA1c (β = 0.21; P = 0.01), and logIPAQ-SF score (β = –0.17; P = 0.04) as predictors of the skin AF after adjustment for sex and WHR (R2 = 0.36; P < 0.0001).Implications
Higher physical activity is related to lower accumulation of AGEs in patients with T1D. Our study provides new insight into the beneficial effects of physical activity in T1D according to tissue accumulation of AGEs. 相似文献63.
Ivan Stankovic Aleksandra Janicijevic Aleksandra Dimic Milica Stefanovic Radosav Vidakovic Biljana Putnikovic 《Annals of medicine》2018,50(2):128-138
Objectives: Bundle branch blocks (BBB)-related mechanical dyssynchrony and dispersion may improve patient selection for device therapy, but their effect on the natural history of this patient population is unknown.Methods: A total of 155 patients with LVEF?≤?35% and BBB, not treated with device therapy, were included. Mechanical dyssynchrony was defined as the presence of either septal flash or apical rocking. Contraction duration was assessed as time interval from the electrocardiographic R-(Q-)wave to peak longitudinal strain in each of 17 left ventricular segments. Mechanical dispersion was defined as either the standard deviation of all time intervals (dispersionSD) or as the difference between the longest and shortest time intervals (dispersiondelta). Patients were followed for cardiac mortality during a median period of 33 months.Results: Mechanical dyssynchrony was not associated with survival. More pronounced mechanical dispersiondelta was found in patients with dyssynchrony than in those without. In the multivariate regression analysis, patients’ functional class, diabetes mellitus and dispersiondelta were independently associated with mortality.Conclusions: Mechanical dispersion, but not dyssynchrony, was independently associated with mortality and it may be useful for risk stratification of patients with heart failure (HF) and BBB.
- Key Messages
Mechanical dispersion, measured by strain echocardiography, is associated with poor outcome in heart failure with a severely depressed left ventricular function and bundle branch blocks.
Mechanical dispersion may be useful for risk stratification of patients with heart failure and bundle branch blocks.
64.
65.
Heikkinen Aki T. Friedlein Arno Matondo Mariette Hatley Oliver J. D. Petsalo Aleksanteri Juvonen Risto Galetin Aleksandra Rostami-Hodjegan Amin Aebersold Ruedi Lamerz Jens Dunkley Tom Cutler Paul Parrott Neil 《Pharmaceutical research》2015,32(1):74-90
Pharmaceutical Research - Beagle dogs are used to study oral pharmacokinetics and guide development of drug formulations for human use. Since mechanistic insight into species differences is needed... 相似文献
66.
Ivan Ranković Vladimir Milivojević Aleksandra PavlovićMarković Mihailo Bezmarević 《World journal of gastroenterology : WJG》2022,28(4):497-499
Elaboration of carotid atherosclerosis in the setting of hepatitis B virus(HBV)infection should emphasize the significance of extrahepatic manifestations of the infection pathogenesis.Diverse processes comprise the pathoevolution of HBV infection,rendering it a multi-systemic disease in its essence.Our work not only exemplified atherosclerosis as an often-underestimated contributor to the severity of HBV infection but has also highlighted the bidirectional relationship between the two.Therefore,it is suggested that HBV-induced inflammation is one of the root causes of atherosclerosis,which in turn has a consequent effect on the severity of the chronic infection disease state,creating a vicious cycle.Additionally,we coupled prior data with the current concepts of HBV infection to postulate intriguing perspectives and theories. 相似文献
67.
The role of CGRP and afferent nerves in the modulation of pancreatic enzyme secretion in the rat 总被引:1,自引:0,他引:1
Jolanta Jaworek Stanisaw J. Konturek Aleksandra Szlachcic 《Journal of gastrointestinal cancer》1997,22(2):137-146
Summary
Conclusion Stimulation of pancreatic sensory nerves by capsaicin produced secretory effects probably caused, at least in part, by the
release of CGRP.
Background In the pancreas calcitonin gene-related peptide (CGRP) has been localized in the sensory nerves, but its physiological role
is unknown. This study was undertaken to compare the changes of pancreatic enzyme secretion produced by CGRP and by stimulation
or destruction of sensory nerves.
Methods To stimulate sensory nerves, low doses of capsaicin (0.25–0.5 mg/kg) were given intraduodenally to the conscious rats with
chronic pancreatic fistula. To inactivate sensory nerves high doses of capsaicin (100 mg/kg) were given subcutaneously 10
d before tests. For the in vitro experiments pancreatic slices and isolated pancreatic acini were prepared from intact and
capsaicin-denervated rats.
Results In conscious rats, CGRP given subcutaneously (5–10 μg/kg) and low doses of capsaicin given intraduodenally reduced basal pancreatic
secretion. In isolated pancreatic acini, CGRP (10−10–10−6
M), but not capsaicin, increased basal or secretagog-stimulated amylase release. In pancreatic slices (containing nerve fibers)
capsaicin (10−10–10−6
M) increased enzyme secretion, and this secretion was abolished by previous inactivation of sensory nerves by this neurotoxin.
Capsaicin deactivation did not affect the secretory response of pancreatic acini to CGRP, cerulein, or urecholine. Sensory
denervation by capsaicin did not change basal protein secretion, but reduced that produced by feeding or diversion of pancreatic
juice to the exterior during first 2 h of the tests. 相似文献
68.
The primary identified function of complement receptor 1 (CR1/CD35) on primate erythrocytes is to bind complement-tagged inflammatory particles including microbes and immune complexes. When erythrocytes circulate through liver and spleen, sinusoidal phagocytes remove CR1-adherent particles and erythrocytes return to the circulation. This process of immune adherence clearance is important for host defense and prevention of autoimmunity. CR1 was previously described as clustered in the human erythrocyte membrane, which was thought to be necessary for binding complement-opsonized particles. In contrast, we demonstrate that on erythrocytes CR1 is not clustered, but dispersed, and able to bind complement-tagged particles. When fresh erythrocytes are solubilized by nonionic detergent, CR1 partitions to the cytoskeleton fraction. Using a PDZ-peptide array, CR1's cytoplasmic tail, which contains 2 PDZ-motifs, binds PDZ domains 2, 3, and 5 of Fas-associated phosphatase 1 (FAP-1), a scaffolding protein. We show that FAP-1, not previously recognized as an erythroid protein, is expressed on circulating erythrocytes. CR1 and FAP-1 coimmunoprecipitate, which confirms their molecular association. Disperse CR1 on erythrocytes may be advantageous for capturing immune-complexes, while ligation-induced CR1 clustering may prevent ingestion of the erythrocyte during the immune-complex transfer to the macrophages by keeping the opsonic stimulus localized thus preventing phagocyosis. 相似文献
69.
Przybylski G Jarzemska A Czerniak J Siemiatkowska K Gadzińska A Cieśliński K 《Polskie Archiwum Medycyny Wewn?trznej》2008,118(3):143-147
Dermatomyositis (DM) is a connective tissue disease characterized by specific inflammatory lesions in muscle biopsy. It is caused by vasculitis determined by humoral factors with subsequent inflammatory cell accumulation, mainly T CD4+ and B cells, which infiltrate myocytes leading to its vacuolization and degeneration (mainly in the skeletal muscles, rarely in the smooth muscles). The incidence of DM is estimated at 1-10 per million in adults and at 1-3.2 per million in children. The autoimmune mechanism of disease induction is not fully recognized. Several lines of evidence showed the link between DM and neoplastic disease. The first report of dermatomyositis associated with stomach cancer, by Stertz, comes from 1916. In the same time, Kankeleit reported DM associated with breast cancer. Presumably, it is the result of immune reaction against antigens common for muscle and neoplastic cells or some paraneoplastic syndrome underlying mechanism. The report presents the case of a 52-year-old woman with DM (diagnosed according to the Bohan and Peter criteria) and with coexistent squamous lung cancer in situ. The left upper lobectomy was performed. No complications in postoperative period were observed. During more than 2 years of follow-up after the surgery, the patient remained in good condition, without DM symptoms, or cancer relapse. Considering that DM may be associated with lung cancer; extensive diagnostic work-up to exclude neoplastic lesions should be performed. Patients aged 40 years or more should be particularly screened. 相似文献
70.
John D. Biglands Montasir Ibraheem Derek R. Magee Aleksandra Radjenovic Sven Plein John P. Greenwood 《JACC: Cardiovascular Imaging》2018,11(5):711-718