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1.
Boyanov MA  Shinkov AD 《Maturitas》2005,51(4):363-369
Objective: We investigated the effects of 1-year tibolone treatment on body weight, body composition and indices of android obesity in postmenopausal women.

Methods: Forty-four postmenopausal women participated in this open-label controlled study; mean age was 51.8 ± 2.21 years and all women were menopausal for 3.8 ± 1.40 years. Twenty-two of them started taking 2.5 mg tibolone (TIB) daily for 1 year, whereas the remaining 22 served as age-matched controls. All subjects underwent a structured interview, physical examination, body composition measurements performed by dual-energy X-ray absorptiometry (DXA) — Hologic QDR 4500 A, as well as bioelectrical body impedance analysis (BI) — Tanita TBF-215, Japan.

Results: The TIB group did not significantly increase their weight (+0.4 kg), while the non-treated controls increased their mean weight by 1.4 kg (p = 0.046). In the TIB group, DXA showed a non-significant body fat decrease by a mean of 0.5 kg and a non-significant lean mass increase by 0.8 kg, while in the control group, fat mass increased by 1.7 kg (p = 0.032) and lean mass did not change. BI revealed that the TIB group had lost some fat (≈0.6 kg, n.s.) and put some free-fat mass (≈1.0 kg, p = 0.048) without changes in total body water. The control group put on some fat (≈1.1 kg, p = 0.042) and lost some body water (≈0.4 kg, n.s.).

Conclusion: Results from both methods of measuring body composition show a similar trend: a decrease in fat mass and an increase in lean mass in TIB treated subjects. From the body composition perspective, tibolone may be regarded as a preferential alternative to conventional hormonal therapy (HT) in postmenopausal women.  相似文献   

2.
D P Eskinazi  R Mihail  W G Dichtel 《Cancer》1985,56(3):490-494
The authors present the case of a 40-year-old white man with an obstructing laryngeal mass. Despite considerable tumor size, results of repeated biopsies revealed widespread carcinoma in situ with chronic inflammation within the subcutaneous tissues, and only after extensive endoscopic "debulking" of the mass was a small focus of invasive carcinoma identified. Just as surprising was the patient's unusual degree of immune competence as estimated to be at least in the upper normal range and definitely much higher than that observed in the other patients with head and neck cancer routinely examined in our department. The immune responsiveness of the patient was evaluated by total lymphocyte count, in vivo skin testing, in vitro blastogenesis, interleukin-2 and interferon-gamma production. The authors postulate that these observations may constitute a rare demonstration of the ability of the immune surveillance system to contain malignancy under physiologic conditions.  相似文献   
3.
The effects of two kinds of induction speed of sevoflurane anesthesia on the EEG pattern were compared in the same individual using medical student volunteers: a first exposure of 4% was given, followed after full recovery, by incremental doses of 1, 2 and 4% successively, each being administered for 10min. The arterial blood level of the anesthetic was measured using gaschromatograph. The changes of EEG pattern during fast induction with 4% were not represented by the abbreviation of those observed during the slow induction with the incremental doses. The administration of 4% induced a sudden appearance of high voltage, rhythmic slow waves of 2–3Hz at 1–3min when the arterial blood anesthetic level increased maximally, which was then followed by a pattern of faster activities of 10–14Hz mixed with 5–8Hz slow waves. In contrast, the administration of incremental doses induced an increase in frequency and amplitude of EEG activities in the light plane, followed by their decreases in deeper planes. The final EEG patterns were identical for both these methods of induction. These findings confirmed our previous hypothesis that not only the arterial blood level of anesthetics but the rate of its increase are important factors determining the EEG pattern of anesthesia.(Avramov MN et al.: Effects of different speeds of induction with sevoflurane on the EEG in man. J Anesth 1: 1–7, 1987)  相似文献   
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5.
Cardiovascular Drugs and Therapy - Cardiac implantable electronic devices (CIEDs) are essential for the management of a variety of cardiac conditions, including tachyarrhythmias, bradyarrhythmias,...  相似文献   
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Transient receptor potential melastatin 2 (TRPM2) is a Ca2+-permeable cation channel expressed in immune cells of phagocytic lineage, pancreatic β cells, and brain neurons and is activated under oxidative stress. TRPM2 activity is required for immune cell activation and insulin secretion and is responsible for postischemic neuronal cell death. TRPM2 is opened by binding of ADP ribose (ADPR) to its C-terminal cytosolic nudix-type motif 9 (NUDT9)-homology (NUDT9-H) domain, which, when expressed in isolation, cleaves ADPR into AMP and ribose-5-phosphate. A suggested coupling of this enzymatic activity to channel gating implied a potentially irreversible gating cycle, which is a unique feature of a small group of channel enzymes known to date. The significance of such a coupling lies in the conceptually distinct pharmacologic strategies for modulating the open probability of channels obeying equilibrium versus nonequilibrium gating mechanisms. Here we examine the potential coupling of TRPM2 enzymatic activity to pore gating. Mutation of several residues proposed to enhance or eliminate NUDT9-H catalytic activity all failed to affect channel gating kinetics. An ADPR analog, α-β-methylene-ADPR (AMPCPR), was shown to be entirely resistant to hydrolysis by NUDT9, but nevertheless supported TRPM2 channel gating, albeit with reduced apparent affinity. The rate of channel deactivation was not slowed but, rather, accelerated in AMPCPR. These findings, as well as detailed analyses of steady-state gating kinetics of single channels recorded in the presence of a range of concentrations of ADPR or AMPCPR, identify TRPM2 as a simple ligand-gated channel that obeys an equilibrium gating mechanism uncoupled from its enzymatic activity.Transient receptor potential melastatin 2 (TRPM2) belongs to the TRP protein family and is abundantly expressed in brain neurons, bone marrow, phagocytes, pancreatic β cells, and cardiomyocytes, where it forms Ca2+-permeable nonselective cation channels that open under oxidative stress. On contact with pathogens, phagocytic cells produce reactive oxygen species (ROS); the resulting activation of TRPM2 provides the Ca2+ influx necessary for cell migration and chemokine production (1). In pancreatic β cells, TRPM2 activity contributes to glucose-evoked insulin secretion; TRPM2 knock-out mice show higher resting blood glucose levels and impaired glucose tolerance (2).TRPM2 activity is also linked to several pathologic conditions that lead to apoptosis (3). Reperfusion after ischemia results in ROS generation; consequent Ca2+ influx through TRPM2 causes Ca2+ dysregulation and cell death. Certain neurodegenerative diseases, such as Alzheimer’s disease, also involve oxidative stress and TRPM2 activation. In contrast, a loss-of-function TRPM2 mutation identified in patients with amyotrophic lateral sclerosis and Parkinson''s disease dementia (4), as well as two TRPM2 mutations associated with bipolar disorder (5), suggest loss of TRPM2 activity can also cause disease.Similar to most TRP family ion channels, the TRPM2 channel is a homotetramer, and its transmembrane (TM) architecture resembles that of voltage-gated cation channels (6, 7). In addition to the TM domain and an N-terminal cytosolic domain of unknown function, TRPM2 contains an ∼270-residue C-terminal cytosolic nudix-type motif 9 (NUDT9)-homology (NUDT9-H) domain. The latter shows high (∼50%) sequence homology to the soluble mitochondrial enzyme NUDT9, an active ADP ribose (ADPR) pyrophosphatase (ADPRase) from the Nudix hydrolase family, which splits ADPR into AMP and ribose-5-phosphate (8). TRPM2 channels are coactivated by ADPR binding to NUDT9-H (9) and by Ca2+ binding to unidentified intracellular binding sites (10). ADPR is the key that links TRPM2 activation to oxidative stress; in living cells exposed to ROS, ADPR is released from mitochondria (9). In the past, studying TRPM2 channel gating at steady state has been limited by rapid deactivation of TRPM2 currents in cell-free patches (10). This rundown was recently shown to involve a conformational change of the ion selectivity filter, which could be completely prevented by a pore-loop substitution. This “T5L” TRPM2 variant, which shows no rundown but preserves intact regulation of gating by Ca2+ and ADPR (11), provides an unprecedented opportunity to study TRPM2 gating at steady state.Early studies reported slow (∼0.1 s−1) but detectable ADPRase activity of isolated purified NUDT9-H (8, 12), classifying TRPM2 into the special group of channel-enzymes (“chanzymes”) that includes TRPM6 and TRPM7 (3) and the CFTR cystic fibrosis transmembrane conductance regulator (CFTR) chloride ion channel (13). TRPM2 pore opening/closure happens on the timescale of the reported ADPRase activity (11), which is consistent with coupling between gating and catalytic activity, as demonstrated for CFTR in which pore gating follows an irreversible cycle tightly linked to ATP binding and hydrolysis at conserved cytosolic domains (14).The involvement of TRPM2 in multiple diseases has made it an emerging therapeutic target. Depending on the disease, both inhibition (e.g., stroke, myocardial infarction, Alzheimer’s disease, chronic inflammation, hyperinsulinism) and stimulation (e.g., diabetes, amyotrophic lateral sclerosis, Parkinson''s disease dementia, bipolar disorder) of TRPM2 activity might be useful therapeutically. Because TRP family channels are involved in diverse processes (3), any useful TRPM2 agonists/antagonists will need to be highly selective. This singles out the NUDT9-H domain, the component unique to TRPM2, as the most attractive drug target. The significance of understanding whether ADPRase activity and gating are coupled is that optimal strategies for modulating fractional occupancy of a particular conformational state are profoundly different for equilibrium systems than for nonequilibrium systems. For most ion channels, pore gating is an equilibrium process, and open probability is modulated simply by energetic stabilization of either open (activators) or closed (inhibitors) channel ground states. In contrast, channels that gate by a nonequilibrium cycle are most efficiently accumulated in either open or closed states by manipulating the stability of transition states for rate-limiting irreversible steps (15). The aim of this study was to examine the tightness of coupling between the ADPRase cycle and specific gating transitions in TRPM2.  相似文献   
8.
We describe a novel neuroinformatic platform, the BAMS2 Workspace ( http://brancusi1.usc.edu ), designed for storing and processing information on gray matter region axonal connections. This de novo constructed module allows registered users to collate their data directly by using a simple and versatile visual interface. It also allows construction and analysis of sets of connections associated with gray matter region nomenclatures from any designated species. The Workspace includes a set of tools allowing the display of data in matrix and networks formats and the uploading of processed information in visual, PDF, CSV, and Excel formats. Finally, the Workspace can be accessed anonymously by third‐party systems to create individualized connectivity networks. All features of the BAMS2 Workspace are described in detail and are demonstrated with connectivity reports collated in BAMS and associated with the rat sensory‐motor cortex, medial frontal cortex, and amygdalar regions. J. Comp. Neurol. 522:3160–3176, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
9.

Background

OCT with its unique image resolution is the ideal method to detect culprit lesion characteristics in different clinical presentations. The identification of inflammatory markers related to plaque characteristics may be of clinical importance.

Methods

Thirty-two patients with acute coronary syndromes (ACS) and fourteen patients with stable angina pectoris (SAP) were enrolled in this study. Culprit lesion morphology was assessed by optical coherence tomography (OCT) in patients with ACS and SAP. The possible relations between serum levels of high sensitivity-C reactive protein (hs-CRP) and interleukin-18 (IL-18) with plaque characteristics were investigated in those patients.

Results

Plaque rupture and thin-cap fibroatheroma (TCFA) were detected more frequently in ACS patients compared with SAP patients, (78.6% vs. 14.3%, p < 0.001, 92.9% vs. 14.3%, p < 0.001, respectively). Higher levels of serum hs-CRP and IL-18 were found in patients with plaque rupture vs. those with no plaque rupture (median value: 19.2 mg/L vs. 1.6 mg/L, p < 0.001 and 219.5 pg/ml vs. 127.5 pg/ml, p = 0.001 respectively), and TCFA vs. those without TCFA (median value: 15.2 mg/L vs. 1.6 mg/L, p = 0.004 and 209.0 pg/ml vs.153.2 pg/ml, p = 0.03 respectively). Serum hs-CRP was the only independent predictor of plaque rupture (p = 0.02, odds ratio 1.1, 95% confidence interval 1.0 to 1.2). A cut-off value of hs-CRP > 4.5 mg/L could detect ruptured plaque with a sensitivity of 91.7% and a specificity of 77.8%.

Conclusions

OCT detected plaque rupture and TCFA more frequent in ACS patients compared with SAP. Elevated hs-CRP and IL-18 were positively related to plaque instability and rupture.  相似文献   
10.
The mental health profile of Bulgaria has been compiled and following analysis of both the factual findings and the process of data collection a report has been prepared. The subject of discussion in the paper concerns several major findings: the discrepancy between what the policy documents state and the actual situation in mental health; the organizational culture, which alienates; and the peculiarities of the process of change and how it is driven under political pressure from outside the country. Analysis extends to encompass the influence of the general health reform on the mental health sector, the deficits of the leadership and how they impact on the effectiveness of the system, and the interdependence between the country's economy and the health sector. A conclusion is made about the need to consolidate the public health approach using the lever of international collaboration in the field of mental health.  相似文献   
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