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991.
Intrauterine growth retardation (IUGR) is associated with increased prevalence, at the adult age, of central obesity, the metabolic syndrome, and its complications (type 2 diabetes and coronary heart disease). Programming of the corticotropic function is one of the mechanisms underlying the above-mentioned phenomenon. An increased passage of active glucocorticoids from the mother to the fetus can act, at the central nervous system level, to program an enhanced response to stress and, at the peripheral level, in adipose tissue to induce an increased local glucocorticoid exposure and sensitivity. In addition to an improvement of the health of pregnant women, early diagnosis of metabolic and hormonal disturbances is important in children with IUGR, in order to prevent a compensatory catch-up growth and its subsequent obesity, and to set up a therapeutic intervention against the deleterious consequences of hypercorticism.  相似文献   
992.
Objective Cytokeratin 19 (CK19) is a specific cytoskeletal structure for alveolar epithelium. We hypothesized that the levels of CK19 fragments in bronchoalveolar lavage (BAL) fluid could serve as an index of epithelial injury and as a prognosis marker in patients with acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). The aims of our study were, in patients with ALI/ARDS: (1) to measure CK19 fragments concentrations in BAL fluid, (2) to assess its prognostic value, and (3) to identify the cellular source of CK19 in the alveolar space.Design Prospective preliminary study.Setting University hospital surgical ICU.Patients Twenty-two mechanically ventilated patients with ALI/ARDS and 10 non-ventilated control patients. Plasma samples were obtained for 11 ALI/ARDS patients.Measurements and results The concentration of BAL CK19 fragments was higher in patients (median 4916 pg/ml, 25th–75th percentile 2717–10533) than in controls (2208 pg/ml. 767–3923; p = 0.05), and higher in 10 non-survivors (7051 pg/ml, 4372–13371) than in 12 survivors (2888 pg/ml, 1315–5639; p = 0.03 among ALI/ARDS patients). BAL CK19 fragment concentration did not correlate with simplified acute physiologic score, lung injury score or PaO2/FIO2 ratio, but correlated positively with BAL albumin concentration (p = 0.002) and with number of BAL macrophages (p = 0.0001). Plasma CK19 fragment concentrations were 10 times lower than those in BAL. Immunohistochemical staining for CK19 showed a strong labelling of injured detached epithelial cells and hyperplastic epithelium in ALI/ARDS lung samples.Conclusion CK19 fragment concentrations were found to be elevated in BAL fluid in ALI/ARDS patients compared with control subjects. High BAL CK19 fragment levels were associated with a poor prognosis.Electronic supplementary material The electronic reference of this article is . The online full-text version of this article includes electronic supplementary material. This material is available to authorised users and can be accessed by means of the ESM button beneath the abstract or in the structured full-text article. To cite or link to this article you can use the above reference.  相似文献   
993.
Acquired methemoglobinemia is a rare but severe condition associated with oxidizing stressors, most notably medications. Although the symptoms can be life threatening, they usually respond promptly to exposure cessation and methylene blue injection. We describe the first case of methemoglobinemia associated with tetracaine lozenge use. A previously healthy 33-year-old man was admitted with fever, respiratory distress, cyanosis, and acute hemolysis. Physical findings and chest radiograph were normal. Low pulse oximetry readings contrasted with normal partial pressure of oxygen and calculated oxygen saturation. The methemoglobin level was 10.8%. The patient recovered with methylene blue injection and blood transfusions. He reported recent self-medication with tetracaine lozenges for a sore throat during a flu-like illness. No other cause of methemoglobinemia was found.  相似文献   
994.
AIM OF THE STUDY: Cystic dystrophy in heterotopic pancreas (CDHP) is rare. The aim of this study was to evaluate the diagnosis, management, and follow-up of the CDHP. PATIENTS AND METHODS: Between August 1990 and March 2004, 12 patients with CDHP underwent a duodenopancreatectomy. The patients were retrospectively reviewed. RESULTS: There were 11 men and 1 woman with a mean age of 42.4 years (range: 34-54 years). Nine patients (75%) were alcoholic and 8 patients had chronic pancreatitis. The diagnosis of CDHP was performed in 8 patients (66.6%) after the preoperative workup. Seven patient had a medical treatment with octreotid and endoscopic cystic ponction (N=3) or cystic fenestration (N=1). Recurrence of pain was noted after a mean period of 5 months. Three patients had recurrent acute pancreatitis. Duodenopancreatectomy was performed in all cases. The mortality and morbidity rate were respectively 8.3% (N=1) and 25% (N=3). Mean follow-up was 64 months (ranges: 6 - 158 months). One patient was seen 70 months later with epigastric pain and features of acute pancreatitis of the pancreatic stump due to anastomotic stenosis. The other patients were asymptomatic. CONCLUSIONS: Diagnosis of CDHP is difficult. After failure of medical treatment, duodenopancreatectomy can be proposed.  相似文献   
995.
BACKGROUND & AIMS: The nervous system, through the vagus nerve, controls inflammation by decreasing the release of tumor necrosis factor-alpha from endotoxin stimulated macrophages. This anti-inflammatory effect is mediated by an interaction of acetylcholine, the principal neurotransmitter of the vagus nerve, with macrophage cholinergic nicotinic receptors expressing the alpha7 subunit. METHODS: To determine the role of this "nicotinic anti-inflammatory pathway" in experimental pancreatitis, we induced pancreatitis in mice by 12 hourly intraperitoneal injections of cerulein. Pancreatitis was preceded by unilateral left cervical vagotomy or pretreatment with the nicotinic receptor antagonist mecamylamine or by pretreatment with the selective alpha7 nicotinic receptor agonist 3-(2,4-dimethoxybenzylidene) anabaseine (GTS-21). RESULTS: Vagotomy or pretreatment with mecamylamine resulted in an enhanced severity of pancreatitis, as reflected by histology, edema, plasma hydrolases, and interleukin-6 levels. Furthermore, the number of neutrophils migrated to the pancreas was increased in these mice, as shown by myeloperoxidase content and intrapancreatic staining of neutrophils. Conversely, GTS-21 pretreatment strongly decreased the severity of pancreatitis. Pancreatitis-associated pulmonary inflammation was independent of the integrity of the vagus nerve and nicotinic receptors. CONCLUSIONS: This study provides the first evidence for a therapeutic potential of the vagus nerve and the "nicotinic anti-inflammatory pathway" in attenuating inflammation and injury during experimental pancreatitis.  相似文献   
996.
OBJECTIVE: Chronic administration of moderate amounts of red wine has been associated with a protective effect on the cardiovascular system. This study examined whether red wine polyphenols prevent the angiotensin II (Ang II)-induced hypertension and endothelial dysfunction in rats, and, if so, to elucidate the underlying mechanism. METHODS: Hypertensive rats were obtained by a 14-day infusion of Ang II. Red wine polyphenols were administered in the drinking water one week before and during the Ang II infusion. Arterial pressure was measured in conscious rats. Ex vivo vascular relaxation was assessed in organ chambers, vascular superoxide anion production by dihydroethidine and vascular NADPH oxidase expression by immunohistochemistry. RESULTS: Ang II-induced hypertension was associated with decreased relaxation to acetylcholine but not to red wine polyphenols. The Ang II treatment also increased vascular superoxide anion production and expression of nox1 and p22phox NADPH oxidase subunits. Intake of red wine polyphenols prevented the Ang II-induced hypertension and endothelial dysfunction and normalized vascular superoxide anion production and NADPH oxidase subunit expression. Red wine polyphenol treatment alone did not affect blood pressure. CONCLUSION: Intake of red wine polyphenols prevents Ang II-induced hypertension and endothelial dysfunction. Prevention of vascular NADPH oxidase induction and preservation of arterial nitric oxide availability during Ang II administration likely contribute to this effect.  相似文献   
997.
OBJECTIVE: Coinfection of rhesus macaques with human/simian immunodeficiency virus chimeras harbouring the minimal core-promoter/enhancer elements from HIV-1 clade B, C and E viral prototypes (STR-B, STR-C and STR-E) revealed a remarkable dichotomy in terms of spatio-temporal viral replication. The clade C chimera (STR-C) predominated in primary infection. The present study was aimed at identifying the origin of STR-C plasma viraemia at this infection phase. DESIGN: By competing isogenic viruses differing only in their promoters, it was possible to identify subtle phenotypical differences in viral replication kinetics and compartmentalization in vivo. METHODS: Two rhesus macaques were coinfected by the three STR chimeras and the relative colonization of different compartments, particularly blood and stool, was determined for each chimera. Moreover, growth competition experiments in thymic histocultures enriched in interleukin (IL)-7 were performed and relative percentages of chimeras were estimated in supernatants and thymocytes lysates at different time points. RESULTS: It is demonstrated here that at the peak of primary infection, preferential replication of STR-C was supported by the gut-associated lymphoid tissue (GALT), an IL-7 rich microenvironment. This was shown by the correlation of the RNA viral genotype in blood and stools, compartments directly draining virions from the GALT. Thymic histocultures confirmed that replication of STR-C is particularly susceptible to this cytokine, compared to its STR-B and STR-E counterparts. CONCLUSIONS: These data show that the GALT cytokine network may well favour HIV-1 clade C replication during primary infection. This could result in enhanced transmission.  相似文献   
998.
OBJECTIVE: To investigate the influence of genetic variability on the phenotypic expression of systemic sclerosis (SSc), by testing possible associations between single nucleotide polymorphisms (SNP) in IL13RA1 and IL13RA2 genes and SSc in a Caucasian population. METHODS: As IL13RA1 and IL13RA2 are located on the X chromosome and SSc occurs far more frequently in women than in men, only women were genotyped. The study group comprised 97 women with SSc, 36 with diffuse (dcSSc) and 61 with limited (lcSSc) cutaneous forms of disease, and 109 healthy controls. Patients and controls were Caucasian. We investigated 4 SNP in IL13RA1 and 3 in IL13RA2 by polymerase chain reaction amplifications and enzymatic digestion or primer extension reactions and denaturing high-performance liquid chromatography. RESULTS: We detected an association between IL13RA2 rs638376 and patients with SSc [p = 0.004, odds ratio (OR) = 1.85, confidence interval (CI) 1.22-2.74, p corr = 0.02], as well as with dcSSc in that subgroup of patients (p = 0.01, OR 2.22, 95% CI 1.27-3.89, p corr = 0.05). The IL13RA2 rs638376G allele frequency was higher in patients with SSc (51.6%) than in controls (36.4%, p = 0.003, OR 1.86, 95% CI 1.24-2.79, p corr = 0.015) and in the subgroup with dcSSc (57.6%) than in controls (36.4%, p = 0.003, OR 2.37, 95% CI 1.35-4.15, p corr = 0.015). One other IL13RA2 SNP was only associated with the dcSSc subgroup: the IL13RA2 rs5946040G allele was more common in patients with dcSSc (33.8%) than in controls (17%, p = 0.004, OR 2.5, 95% CI 1.36-4.60, p corr = 0.02). CONCLUSION: Our data suggest that IL13RA2 gene polymorphisms may be involved in susceptibility to SSc. Further studies are under way to show that they contribute to disease.  相似文献   
999.
OBJECTIVE: Idiopathic inflammatory myopathies (IIM) are a heterogeneous group of diseases characterized by chronic inflammation of muscles. We investigated the role of cellular adhesion molecules implicated in the cohesion of endothelial cells in IIM. METHODS: In 22 patients with IIM we investigated plasma concentrations of soluble junctional adhesion molecules [platelet-endothelial cell adhesion molecule (sPECAM-1) and sCD146] and cellular adhesion molecules [sP-selectin, sE-selectin, intercellular adhesion molecule (sICAM-1), and vascular cell adhesion molecule (sVCAM-1)] implicated in leukocyte/endothelial cell interactions. Results were compared to a control group. Muscle biopsy samples from 8 out of 22 IIM patients were studied by immunohistochemistry for tissue expression of these molecules and compared to normal muscle samples. PECAM-1 and CD146 expression was also studied using immunoblots from muscle biopsies from 5 patients and 2 controls. RESULTS: We observed distinct patterns of soluble levels and in situ expression between dermatomyositis (DM), polymyositis (PM), and sporadic inclusion body myositis (s-IBM). PM samples showed significantly increased levels of sCD146, sPECAM-1, and s-ICAM1 and increased expression of CD146, CD31, and ICAM-1 in endothelial cells, whereas CD146 and ICAM-1 were also recorded in some muscle fibers. In DM, sE-selectin, sP-selectin, and sPECAM-1 were significantly increased, with abnormal expression of ICAM-1 in endothelial cells and perifascicular muscle fibers. In the small group of s-IBM samples, results were similar to PM, but the only significant increase was the level of sPECAM-1. Immunoblots confirmed increased expression of PECAM-1 and CD146 in all IIM muscles in comparison to controls, with the highest expression in PM and IBM samples. CONCLUSION: We observed abnormal increases of soluble levels of adhesion molecules implicated in endothelial cell junctions in PM (sCD146, sPECAM-1) and to a lesser extent in DM and s-IBM (sPECAM-1). We conclude that the distinctly different profiles between PM/s-IBM and DM reflect differences in the pathophysiological background of these diseases.  相似文献   
1000.
17beta-Hydroxysteroid dehydrogenase type 1 (17beta-HSD1) catalyzes the transformation of estrone (E1) into the most potent estrogen, estradiol (E2), which stimulates cell proliferation and decreases apoptosis. 17beta-HSD1 is often strongly overexpressed in estrogen-dependent diseases (like breast cancer and endometriosis). Thus, this over expressed enzyme is a promising novel target for the development of selective inhibitors, which could be used as drugs for the treatment of these diseases. Using a structure- and ligand-based approach, a pharmacophore model was proposed and a new class of non-steroidal inhibitors of 17beta-HSD1 was designed. Enzyme inhibition was evaluated in vitro using the human enzyme. After identification of the 6-(3'-hydroxyphenyl)-2-naphthol scaffold 1, the potency of this class of inhibitors was further improved by substitution of the 1-position of the naphthalene ring by a phenyl group (compound 18, IC(50)=20nM). Compound 18 also showed a good selectivity toward 17beta-HSD2 and the estrogen receptors alpha and beta.  相似文献   
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