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41.
PURPOSE: To evaluate C-arm computed tomography (CT) and assess its potential impact on hepatic arterial interventions. MATERIALS AND METHODS: Between May 2005 and March 2006, all hepatic arterial interventions for hepatic malignancies were retrospectively reviewed. C-arm CT acquisitions were performed as an adjunct to conventional digital subtraction angiography (DSA). The number of procedures with C-arm CT, the acquisitions per intervention, and the procedure time for all interventions were recorded. The added information provided by C-arm CT was scored as category 1 (no additional information); category 2 (added information without impact on procedure management); or category 3 (added information with impact on procedure management). Intervention types included infusions, radioembolization, embolization, and chemoembolization. A two-sided, two-sample t test was used to compare interventions with and without C-arm CT, and P values less than .05 were considered significant. RESULTS: C-arm CT was used in 86 of 240 interventions (36%) in 135 patients. The mean number of acquisitions per study was 1.9 (range, 1-4). Thirty-five interventions (40.7%) were scored as category 2 and 16 interventions (18.6%) were scored as category 3. Chemoembolization was associated with the highest percentage of C-arm CT investigations classified as category 2 and 3 assessed per intervention. The mean procedure time was significantly longer (18 minutes) when C-arm CT was used (P<.001). CONCLUSIONS: C-arm CT provides additional imaging information beyond DSA during hepatic arterial interventions (approximately 60%), and this information impacted procedure management in 19% of cases. C-arm CT offers the greatest opportunity for additional information during chemoembolization procedures and is responsible for a significant but acceptable increase in procedure time for this type of hepatic intervention.  相似文献   
42.
Diets rich in fruits and vegetables have been associated with reduced risks for many types of cancers. Avocado (Persea americana Mill.) is a widely consumed fruit containing many cancer preventing nutrients, vitamins and phytochemicals. Studies have shown that phytochemicals extracted from the avocado fruit selectively induce cell cycle arrest, inhibit growth, and induce apoptosis in precancerous and cancer cell lines. Our recent studies indicate that phytochemicals extracted with 50% Methanol from avocado fruits help in proliferation of human lymphocyte cells and decrease chromosomal aberrations induced by cyclophosphamide. Among three concentrations (100 mg, 150 mg and 200 mg per Kg Body Weight), the most effective conc. of extract was 200 mg/Kg Body Wt. It decreased significant level of numerical and structural aberrations (breaks, premature centromeric division etc. up to 88%, p < 0.0001)), and accrocentric associtation within D & G group (up to 78%, p = 0.0008). These studies suggest that phytochemicals from the avocado fruit can be utilized for making active chemoprotective ingredient for lowering the side effect of chemotherapy like cyclophosphamide in cancer therapy.  相似文献   
43.
Coping with intermittent social stress is an essential aspect of living in complex social environments. Coping tends to counteract the deleterious effects of stress and is thought to induce neuroadaptations in corticolimbic brain systems. Here we test this hypothesis in adult squirrel monkey males exposed to intermittent social separations and new pair formations. These manipulations simulate conditions that typically occur in male social associations because of competition for limited access to residency in mixed-sex groups. As evidence of coping, we previously confirmed that cortisol levels initially increase and then are restored to prestress levels within several days of each separation and new pair formation. Follow-up studies with exogenous cortisol further established that feedback regulation of the hypothalamic-pituitary-adrenal axis is not impaired. Now we report that exposure to intermittent social separations and new pair formations increased hippocampal neurogenesis in squirrel monkey males. Hippocampal neurogenesis in rodents contributes to spatial learning performance, and in monkeys we found that spatial learning was enhanced in conditions that increased hippocampal neurogenesis. Corresponding changes were discerned in the expression of genes involved in survival and integration of adult-born granule cells into hippocampal neural circuits. These findings support recent indications that stress coping stimulates hippocampal neurogenesis in adult rodents. Psychotherapies designed to promote stress coping potentially have similar effects in humans with major depression.  相似文献   
44.
An efficient and simple three‐component domino synthesis of some new dihydropyrimidines (DHPMs) from aromatic aldehydes, 1,3‐dicarbonyl compounds and N‐(3‐chloro‐4‐fluorophenyl)urea using molecular iodine as catalyst is described. The 1‐substituted dihydropyrimidines were isolated in good to excellent yields (78‐90%) within a short reaction time (4‐6 h) at ambient temperature. The biological evaluation revealed that the newly synthesized compounds ( 4a ‐ i and 5a ‐ i ) exhibited moderate antimycobacterial activity against Mycobacterium tuberculosis H37 RV.  相似文献   
45.
Cytosolic phospholipase A2 alpha (cPLA2 alpha) is the rate-limiting enzyme for release of arachidonic acid, which is converted primarily to prostaglandins via the cyclooxygenase (COX) 1/2 pathways, and leukotrienes via the 5-lipoxygenase (LO) pathway. We utilized inhibitors of cPLA2 alpha, COX-1/2 and 5-LO to determine the potential roles of these enzymes in development of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Blocking cPLA2 alpha prevented EAE development and greatly reduced antigen-induced production of Th1-type cytokines and IL-17. Blocking COX-1/2 delayed onset and reduced severity of EAE, and reduced production of Th1-type cytokines, but not IL-17. Blocking 5-LO delayed onset and reduced cumulative severity of EAE, but did not reduce production of Th1-type cytokines or IL-17. Finally, blockade of cPLA2 alpha from the onset of clinical EAE reduced duration of EAE relapses. Therefore, cPLA2 alpha represents a potential therapeutic target for treatment of MS.  相似文献   
46.
Insulin has a free fatty acid (FFA)-suppressive effect, vascular endothelial growth factor (VEGF)- and matrix metalloproteinase (MMP)-lowering effect, and a potential myocardial-protective effect. Whether low-dose insulin exerts these effects in patients with acute myocardial infarction (MI) was investigated. Thirty-two patients administered thrombolytics and heparin were randomly assigned to a modified glucose-insulin-potassium (GIK) regimen (insulin 2.5 U/hour, dextrose and potassium titrated to prevent hyperglycemia) or normal saline solution and potassium (controls) for 48 hours. Plasma FFA, serum VEGF, pro-MMP-1, and myoglobin were measured at baseline and sequentially for 48 hours. FFA concentrations were increased at baseline; increased further in the first 4 hours in controls (p相似文献   
47.
48.
IntroductionRecently, there has been much discussion in the literature about how to determine the meaningfulness of results generated from a patient-reported outcome measure. A number of reviews have shown that there are two main approaches: anchor- and distribution-based approaches for determining the minimum important difference (MID) for a new measure. There are issues with calculating an MID using each method: Will the two approaches give the same estimate? If the estimates differ, how do you decide on one estimate? Would asking patients directly be more beneficial?AimA case study was presented to address these issues based on a newly developed diary assessing number of satisfactory sexual events (SSEs) per week in women with hypoactive sexual desire disorder (HSDD).MethodsAnchor- and distribution-based estimates were generated from data gathered in two double-blind, placebo-controlled, parallel group trials for the treatment of HSDD (N = 788). A novel interview study was used to ask women directly about an MID for SSEs (N = 77).Main Outcome MeasuresDefining the MID for an SSE diary in women with HSDD.ResultsThe estimates varied, producing a range of mean MID estimates between 0.04 and 0.46 SSEs per week.ConclusionsWe recommend that rather than defining the MID, a range should be selected from the set of estimates formed by the limits of the 95% confidence intervals. Symonds T, Spino C, Sisson M, Soni P, Martin M, Gunter L, and Patrick DL. Methods to determine the minimum important difference for a sexual event diary used by postmenopausal women with hypoactive sexual desire disorder.  相似文献   
49.
OBJECTIVE: Periodic breathing (PB) is a common respiratory pattern in preterm infants. Our aim was to determine the influence of PB on the pattern of oxygenation in preterm infants with significant PB at discharge from hospital. STUDY DESIGN: Overnight 12-hour recordings of arterial O(2) saturation (SpO(2)), impedance breathing movement, nasal thermistor signals for airflow, and heart rate were performed in all preterm infants < or = 34 weeks' gestational age at birth, prior to hospital discharge. Infants had recovered from their neonatal complications and were not receiving methylxanthines or supplemental oxygen. Data from 28 infants who had significant PB (> or = 5% of quiet time artifact free) were further analyzed. Gestational age at birth was (median, range) 32 (27-34) weeks, and gestational age at recording was 35 (33-37) weeks. RESULTS: The baseline SpO(2) was 98% (92-100%). During PB, all infants had episodes when SpO(2) fell > or = 5%, and all except one had episodes when SpO(2) was < 90%. Sixty episodes of prolonged desaturation (SpO(2) < or = 80% for >/ or = 4 seconds) were recorded in 10 infants: 31 occurred during PB, 16 during hypopnea, 10 during apnea, and 3 occurred in the absence of these breathing patterns. During PB, nine infants (32%) had 1 to 13 episodes of prolonged desaturation, lasting 9 (4-76) seconds. CONCLUSION: We conclude that PB is a common cause of prolonged desaturation in preterm infants at discharge.  相似文献   
50.
BACKGROUND: Serious adverse events may occur from the use of disease modifying antirheumatic drugs (DMARDs) used to treat rheumatoid arthritis. We describe preliminary data from a regional surveillance scheme. Our aims were to identify a broad range of potential adverse events, to identify deficiencies in care and examine the management of common events in order to improve care. METHODS: Adverse events were sought by regular postcards to clinicians in the West Midlands region of the UK. Each reported case was carefully described and the opinions of at least three peer-reviewers were sought on cause-effect relationships, the potential for prevention and the appropriateness of management. RESULTS: Forty-four serious adverse events associated with DMARD use were reported between December 1999 and October 2001. Events included eight patients with malignancies, two with pancytopenia taking methotrexate, three with septic arthritis, and two with septicaemias. Fifteen cases have been peer-reviewed in detail, so far. At least two reviewers thought that eight events were related to DMARD use and that two were preventable. Agreement between pairs of reviewers was fair or moderate (weighted kappa 0.23-0.5). DISCUSSION: We have successfully implemented a regional system for identifying potential drug-related serious adverse events. A diverse range of potential drug-related events has been seen. Early analyses have highlighted the difficulties of determining cause-effect relationships between a drug and an event.  相似文献   
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