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991.
Background: At the Istituto di Clinica Medica Generale e Cardiologia (Florence, Italy), the widespread use of percutaneous coronary intervention (PCI) has markedly changed the hospital course of patients with acute myocardial infarction (AMI). These patients are typically transferred to the coronary care unit (CCU) only after primary PCI, whereas during the thrombolytic era, patients were first admitted to CCU before reperfusion. Objectives and Methods: The incidence, timing and setting of complications from symptom onset to hospital discharge in 689 consecutive AMI patients undergoing PCI were evaluated. Results: Ventricular fibrillation occurred in 11% of patients, and most episodes (94.7%) occurred before or during PCI. Of all patients, 6.3% developed complete atrioventricular block (CAVB), and in 86.3% of these cases, the CAVB occurred before or during PCI; in 94.5%, a CAVB resolution occurred in the catheterization laboratory (CL). Thirty-one patients (4.5%) had impending shock on admission to the CL. Cardiogenic shock developed in 2 9 patients (4.2%), mostly in the prehospital phase or in the CL. Only four patients (less than 1%) developed cardiogenic shock later during their hospital course. Similarly, circulatory and ventilatory support, as well as temporary pacing and cardiac defibrillation, were used mostly in the prehospital phase or in the CL. During the CCU stay, 45 patients (6.5%) had hemorrhagic or vascular complications, and the incidence of post-PCI ischemia and early reocclusion of the culprit vessel were low (2.1% and 0.6%, respectively). Thus, cardiac complications usually associated with AMI were observed mainly before hospital admission or in the CL during the reopening of the target vessel. These complications were rarely observed after a successful PCI. Conclusions: For AMI patients, the CL is not only the site of PCI, it is also where most life-threatening cardiac complications are observed and treated.  相似文献   
992.
OBJECTIVES: Pre-eclampsia is associated with vascular endothelial dysfunction, adverse pregnancy outcome and cardiovascular disease in later life. An inadequate nitric oxide availability related to polymorphisms in the endothelial nitric oxide synthase gene (eNOS) might predispose to the disease. METHODS: We investigated the role of eNOS T-786C, G894T and 4a4b polymorphisms in predisposing to both pre-eclampsia and the recurrence of negative pregnancy events, per se and in the presence of angiotensin-converting enzyme (ACE) DD genotype, and investigated their influence on maternal-fetal flow in 106 non-thrombophilic women with a history of pre-eclampsia, compared with 106 women with a history of normal pregnancy. RESULTS: No association between eNOS polymorphisms and predisposition to pre-eclampsia was found; nevertheless, the contemporary presence of eNOS 894TT and -786CC genotypes represented a susceptibility factor to the disease. In 48 out of 106 women, documented complications (pre-eclampsia and fetal growth restriction) were present in the current pregnancy. The eNOS 894TT genotype influenced the risk of recurrence of negative events (odds ratio = 5.45), particularly in contemporary women homozygous for both eNOS 894TT and ACE DD genotypes (odds ratio = 11.4). Throughout the pregnancy, a progressive alteration of maternal-fetal flow indices was found in women carrying the eNOS 894TT genotype, and this effect was strengthened in women with the contemporary presence of the ACE DD genotype. CONCLUSIONS: An original finding is the increased risk of pre-eclampsia and recurrence of pregnancy negative events, probably by modulating the maternal-fetal flow, in women homozygous for the eNOS 894T allele previously analyzed for the ACE I/D polymorphism.  相似文献   
993.
BACKGROUND: C-reactive protein (CRP) predicts cardiovascular outcome. Oxidative stress is considered to be involved in endothelial alteration. We hypothesized that in essential hypertension (EH), oxidative stress, as measured by 8-iso-prostaglandin-F(2alpha) (8-iso-PGF(2alpha)), should be associated with increased CRP and endothelial activation, as evaluated by soluble intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1) plasma levels. METHODS: In 83 subjects with mild EH and in 50 healthy control subjects we measured, in basal conditions, plasma levels of hs-CRP, 8-iso-PGF(2alpha), ICAM-1 and VCAM-1, and tumor necrosis factor-alpha (TNF-alpha). RESULTS: Subjects with EH had higher levels of 8-iso-PGF(2alpha) (P < .0001), CRP (P < .001), ICAM-1 and VCAM-1 (P < .001), and TNF-alpha (P < .001) than did control subjects. We divided successively EH according to CRP values (<1, 1-3, >3 mg/L), and we observed increasing and significantly different levels of the endothelial parameters and of TNF-alpha along with increasing CRP. Linear analysis of correlation pointed out significant correlation of CRP with 8-iso-PGF(2alpha) (r = 0.730, P < .001), ICAM-1 and VCAM-1 (r = 0.642 and 0.468, P < .001 respectively), and TNF-alpha (r = 0.609, P < .001). Multiple regression analysis using CRP as a dependent variable confirmed the relationship of CRP with systolic blood pressure (beta 0.216, P = 0.039) and with 8-iso-PGF(2alpha) (beta 0.602, P = .0001). CONCLUSIONS: Our data demonstrate that in EH, inflammatory molecules such as CRP and TNF-alpha are increased and related to both oxidative stress and endothelial activation.  相似文献   
994.
Tumor M2-Pyruvate Kinase, a New Metabolic Marker for Pancreatic Cancer   总被引:16,自引:0,他引:16  
An isoenzyme of pyruvate kinase (Tu M2-PK) is overexpressed by tumor cells and can be measured in blood by a specific immunoenzymatic assay. Our objective was to investigate the diagnostic value of Tu M2-PK in comparison with that of CA 19-9 in pancreatic cancer. We studied 265 subjects: 60 with histologically confirmed pancreatic cancer, 43 with benign pancreatic diseases (acute and chronic pancreatitis), 5 with benign cystic neoplasms of the pancreas, 9 with neuroendocrine tumors, 77 with other abdominal malignancies, 47 with benign digestive diseases, and 24 healthy controls. Levels of plasma Tu M2-PK and serum CA 19-9 were determined by commercially available specific immunoassays. The diagnostic sensitivity and specificity of Tu M2-PK for pancreatic cancer were 85 and 41%, respectively, while those of CA 19-9 were 75 and 81%. The combination of the two tests significantly increased sensitivity (97%) but lowered specificity (38%). In discriminating between pancreatic cancer and acute or chronic pancreatitis, Tu M2-PK turned out to be less accurate than CA 19-9. In patients without pancreatic tumor, cholestasis appeared not to affect the values of Tu M2-PK, while CA 19-9 was found to be significantly higher. Tu M2-PK was also abnormally high in the majority of patients with other digestive malignancies or neuroendocrine tumors. The results demonstrate that Tu M2-PK has a satisfactory sensitivity but a poor specificity in the diagnosis of pancreatic cancer. Used together with CA 19-9, the sensitivity increases considerably.  相似文献   
995.
OBJECTIVE: The diagnosis of growth hormone (GH) deficiency (GHD) in adults is based on a reduced peak GH response to provocative tests, such as the insulin tolerance test (ITT) and the GH-releasing hormone-arginine (GHRH-ARG) test. However, the cut-off limits of peak GH response in lean subjects are not reliable in obese patients; this is noteworthy since adult GHD is often associated with obesity. Aim of this study was to evaluate the diagnostic cut-off limits of peak GH response to the GHRH-ARG test in overweight and obese as well as in lean population. DESIGN AND METHODS: The GH responses to the GHRH-ARG test were studied in 322 patients with organic hypothalamic-pituitary disease and in 318 control subjects. Patients were subdivided into two groups on the basis of the number of pituitary hormone deficits, except for GH deficiency: (a) patients with total pituitary hormone deficit (TPHD) and (b) patients without or with no more than two pituitary hormone deficits (PHD). Both patients and control subjects were divided into three subgroups according to body mass index (BMI): lean (BMI <25 kg/m(2)), overweight (BMI > or = 25 and <30 kg/m(2)) and obese (BMI > or =30 kg/m(2)). TPHD patients were assumed to be GH deficient, whereas PHD patients may include subjects with either normal or impaired GH secretion. The statistical analysis was carried out by the Receiver-Operating Characteristic curve analysis (Medcalc 7.2). The diagnostic cut-off points were calculated for lean, overweight and obese subjects to provide optimal separation of GH-deficient patients and control subjects according to two criteria: (1) a balance between high sensitivity and high specificity; (2) to provide the highest pair of sensitivity/specificity values for GH deficiency. RESULTS: In the lean population the best pair of values, with highest sensitivity as 98.7% and highest specificity as 83.7%, was found using a peak GH cut-off point of 11.5 mug/l. In the overweight population the best pair of values, 96.7 and 75.5%, respectively, was found using a peak GH cut-off point of 8.0 mug/l. In the obese population the best pair of values, 93.5 and 78.3%, respectively, was found using a peak GH cut-off point of 4.2 mug/l. Applying the above mentioned cut-off points, among PHD patients we found that 80 subjects (72%) were GHD whereas 31 (28%) had normal GH secretion. CONCLUSIONS: In conclusion the GHRH-ARG test is a reliable tool for the diagnosis of adult GH deficiency in lean, overweight and obese patients, provided that specific BMI-related cut-off limits are assumed.  相似文献   
996.
Medullary thyroid carcinoma (MTC) is a rare tumor originating from thyroid parafollicular C cells, where, in the inherited form, constitutive activation of the RET protooncogene is responsible for unrestrained cell proliferation. We previously demonstrated that somatostatin (SRIF) reduces cell growth in the human MTC cell line TT, which expresses all SRIF receptor (SSTR) subtypes and responds differently to selective SSTR agonists. The antiproliferative mechanism of SRIF and its analogs in MTC is still unclear. Src homology-2-containing protein tyrosine phosphatase-1 (SHP-1), a cytoplasmic protein tyrosine phosphatase (PTP), is activated by somatotropin release-inhibiting factor and reduces mutated RET autophosphorylation in a heterologous system. In this study, we explore the role of PTP activation, in particular of SHP-1, in TT cells, where RET is constitutively activated. In TT cells, SRIF stimulated the PTP activity of SHP-1, which was associated with proliferation inhibition and with reduction in the MAPK pathway activation. Blockade of PTP activity with sodium orthovanadate induced cell proliferation and MAPK phosphorylation and blunted the inhibitory effects of SRIF. Moreover, SHP-1 associates with SSTR2 depending on its activation. By using a MAPK kinase inhibitor, we demonstrated that TT cell growth depends on MAPK pathway activation. Furthermore, in TT cells overexpressing SHP-1, cell proliferation and MAPK signaling were strongly down-regulated, whereas in TT cells transfected with a dominant negative form of SHP-1, cell proliferation and MAPK signaling were markedly induced. Our data demonstrate that SRIF inhibitory effects on TT cell proliferation are mediated, at least in part, by SHP-1, which acts through a MAPK-dependent mechanism.  相似文献   
997.
Ontogenesis of T cells in the thymus is a complex process whose molecular control is poorly understood. The present study investigated microRNAs involved in human thymocyte differentiation by comparing the microRNA expression profiles of thymocytes at the double-positive, single-positive CD4(+) and single-positive CD8(+) maturation stages. Microarray analysis showed that each thymocyte population displays a distinct microRNA expression profile that reflects their developmental relationships. Moreover, analysis of small-RNA libraries generated from human unsorted and double-positive thymocytes and from mature peripheral CD4(+) and CD8(+) T lymphocytes, together with the microarray data, indicated a trend toward up-regulation of microRNA expression during T-cell maturation after the double-positive stage and revealed a group of microRNAs regulated during normal T-cell development, including miR-150, which is strongly up-regulated as maturation progresses. We showed that miR-150 targets NOTCH3, a member of the Notch receptor family that plays important roles both in T-cell differentiation and leukemogenesis. Forced expression of miR-150 reduces NOTCH3 levels in T-cell lines and has adverse effects on their proliferation and survival. Overall, these findings suggest that control of the Notch pathway through miR-150 may have an important impact on T-cell development and physiology.  相似文献   
998.
To specify the incidence and risk factors for secondary autoimmune diseases (ADs) after HSCT for a primary AD, we retrospectively analyzed AD patients treated by HSCT reported to EBMT from 1995 to 2009 with at least 1 secondary AD (cases) and those without (controls). After autologous HSCT, 29 of 347 patients developed at least 1 secondary AD within 21.9 (0.6-49) months and after allogeneic HSCT, 3 of 16 patients. The observed secondary ADs included: autoimmune hemolytic anemia (n = 3), acquired hemophilia (n = 3), autoimmune thrombocytopenia (n = 3), antiphospholipid syndrome (n = 2), thyroiditis (n = 12), blocking thyroid-stimulating hormone receptor antibody (n = 1), Graves disease (n = 2), myasthenia gravis (n = 1), rheumatoid arthritis (n = 2), sarcoidosis (n = 2), vasculitis (n = 1), psoriasis (n = 1), and psoriatic arthritis (n = 1). After autologous HSCT for primary AD, the cumulative incidence of secondary AD was 9.8% ± 2% at 5 years. Lupus erythematosus as primary AD, and antithymocyte globulin use plus CD34(+) graft selection were important risk factors for secondary AD by multivariate analysis. With a median follow-up of 6.2 (0.54-11) years after autologous HSCT, 26 of 29 patients with secondary AD were alive, 2 died during their secondary AD (antiphospholipid syndrome, hemophilia), and 1 death was HSCT-related. This European multicenter study underlines the need for careful management and follow-up for secondary AD after HSCT.  相似文献   
999.
1000.
The iron need in pregnancy is significantly higher in comparison to that in the nonpregnant state. The iron absorbed during pregnancy is used for expansion of the maternal erythrocyte mass, to fulfill the fetus's iron needs, to create placenta, and to cope with blood loss at delivery. Term neonates have a total body store of about 1 g of iron, all derived from the mother. Despite the overall increase in nutritional requirements, biochemical, metabolic, and physiological adjustments of the maternal organism happen in order to meet the extra demands and to support the homeostasis of iron. In all healthy pregnant women with sufficient iron stores, the increased iron absorption is coupled with the mobilization of iron stores. Unfortunately, iron deficiency during pregnancy is alarmingly common. The function of placental transport determines the composition of umbilical cord blood providing nutrients and oxygen to the fetus to ensure appropriate fetal growth. Iron in the developing fetus is accumulated against a concentration gradient and, in the case of maternal iron deficiency, the placenta can protect the fetus significantly through the increased expression of placental transferrin receptor together with a rise in divalent metal transporter 1 (DMT1). Despite the resistance of the fetus to maternal deficiency, any stress that alters placental development or function may have consequences for the developing fetus. Despite its central importance in fetal development, little is known about the mechanism of iron transfer across the placenta. Consequently, it is crucial to understand the molecular basis of placental iron transport in order to optimize the iron intake recommendation, reducing adverse pregnancy outcomes for both the mother and her child.  相似文献   
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