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Anaplastic thyroid carcinoma (ATC) is an aggressive thyroid malignancy with high mortality rate. This malignancy arises in thyroid follicular cells either denovo or with an associated differentiated thyroid carcinoma component. Clinically, it usually presents as a rapidly enlarging mass, pain and locally compressive symptoms. Histopathologic variability and heterogeneity often pose diagnostic challenges, especially in scant and paucicellular specimens. This article describes the clinical, histopathologic and molecular features of ATC and also addresses the associated diagnostic limitations and challenges.  相似文献   
3.
The human visual system is amenable to a number of adaptive processes; one such process, or collection of processes, is the adaptation to blur. Blur adaptation can be observed as an improvement in vision under degraded conditions, and these changes occur relatively rapidly following exposure to blur. The potential important future directions of this research area and the clinical implications of blur adaptation are discussed.  相似文献   
4.
The endovenous revolution has accelerated the development of new techniques and devices for the treatment of varicose veins. The ClariVein® mechanochemical ablation device offers tumescentless treatment with a rotating ablation tip that can theoretically become stuck in tissue. We present the first report of retrograde stripping of the small saphenous vein without anaesthesia following attempted use of the ClariVein® device, without adverse sequelae.  相似文献   
5.
GABAergic interneuron hypofunction is hypothesized to underlie hippocampal dysfunction in schizophrenia. Here, we use the cyclin D2 knockout (Ccnd2−/−) mouse model to test potential links between hippocampal interneuron deficits and psychosis-relevant neurobehavioral phenotypes. Ccnd2−/− mice show cortical PV+ interneuron reductions, prominently in hippocampus, associated with deficits in synaptic inhibition, increased in vivo spike activity of projection neurons, and increased in vivo basal metabolic activity (assessed with fMRI) in hippocampus. Ccnd2−/− mice show several neurophysiological and behavioral phenotypes that would be predicted to be produced by hippocampal disinhibition, including increased ventral tegmental area dopamine neuron population activity, behavioral hyperresponsiveness to amphetamine, and impairments in hippocampus-dependent cognition. Remarkably, transplantation of cells from the embryonic medial ganglionic eminence (the major origin of cerebral cortical interneurons) into the adult Ccnd2−/− caudoventral hippocampus reverses these psychosis-relevant phenotypes. Surviving neurons from these transplants are 97% GABAergic and widely distributed within the hippocampus. Up to 6 mo after the transplants, in vivo hippocampal metabolic activity is lowered, context-dependent learning and memory is improved, and dopamine neuron activity and the behavioral response to amphetamine are normalized. These findings establish functional links between hippocampal GABA interneuron deficits and psychosis-relevant dopaminergic and cognitive phenotypes, and support a rationale for targeting limbic cortical interneuron function in the prevention and treatment of schizophrenia.Precursors of most γ-aminobutyric acid (GABA)-releasing interneurons of the cerebral cortex and the hippocampus originate in the embryonic medial ganglionic eminence (MGE) (13). A subpopulation of MGE-derived cells differentiates into fast-spiking, parvalbumin-expressing (PV+) interneurons that tightly regulate the activity and synchronization of cortical projection neurons (2, 4). Structural and functional deficits in PV+ interneurons are hypothesized as a pathophysiological mechanism in schizophrenia and psychotic disorders (46).Although psychotic disorders are clearly heterogeneous in etiology, disinhibition within temporolimbic cortical circuits is postulated as a core pathophysiology underlying positive symptoms (e.g., delusions and hallucinations) and a subset of cognitive disturbances that manifest with psychosis (4, 5, 7). Postmortem studies of brains from individuals with psychotic disorders show reduced molecular markers of the number and/or function of PV+ interneurons in the hippocampus (6, 8). Consistent with these observations, basal metabolic activity in the hippocampus, as measured with functional magnetic resonance imaging (fMRI), is increased in schizophrenia, a phenotype that predicts psychosis and positive symptom severity (5, 7). This abnormal resting activity is postulated to underlie abnormal recruitment of hippocampal circuits during cognitive performance (5, 9). Striatal dopamine (DA) release capacity is also increased and correlated with positive symptoms in schizophrenia and its risk states (10, 11). Importantly, hippocampal hyperactivity may contribute to DA dysregulation (12), because rodent studies show that caudoventral hippocampal (in the primate, anterior hippocampal) efferents regulate the activity of DA neurons and medial striatal DA release (13, 14).Thus, converging evidence implicates hippocampal disinhibition in the abnormal striatal DA transmission and cognitive impairment in schizophrenia. However, the role of hippocampal inhibitory interneurons in psychosis-relevant circuitry remains to be established. To this end, we used the cyclin D2 (Ccnd2) knockout mouse model (15), which displays a relatively selective deficit in cortical PV+ interneurons, and transplantation of interneuron precursors from the MGE to elucidate relationships between reduced hippocampal GABA interneuron function and multiple psychosis-relevant phenotypes, and to explore a novel treatment strategy for psychosis.  相似文献   
6.
To determine the factors that influenced doctors' prioritization and decisions on safe waiting time for coronary artery bypass surgery, 50 'paper patients', based on a random sample of cases who actually had surgery, were assessed by 33 clinicians. We used linear regression models to reflect the impact of clinical and non-clinical 'cues' on safe waiting time and priority decisions. The benefits of surgery tended to be over-estimated. For example, the average perceived gain in life expectancy for patients with left main-stem disease was 6.74 years. However, models incorporating only the perceptions of benefit as independent variables (i.e. the anticipated symptom reduction, MI risk reduction and life expectancy extension), had only modest explanatory power (mean R2 was 0.55 for safe waiting time, and 0.56 for priority decisions). Models which incorporated perceptions of benefit and the cases' clinical and non-clinical characteristics had generally much higher explanatory power (mean R2, 0.83 and 0.86, respectively). Lifestyle and demographic variables had much less impact on the doctors' judgements than the major clinical cues of angina severity and left main-stem stenosis. Demographic and lifestyle cues had different impacts on safe waiting time and priority for about 25% of doctors.   相似文献   
7.
The inactivation of HIV by gamma-radiation was studied in frozen and liquid plasma; a reduction of the virus titer of 5 to 6 logs was achieved at doses of 5 to 10 Mrad at -80 degrees C and 2.5 Mrad at 15 degrees C. The effect of irradiation on the biologic activity of a number of coagulation factors in plasma and in lyophilized concentrates of factor VIII (FVIII) and prothrombin complex was examined. A recovery of 85 percent of the biologic activity of therapeutic components present in frozen plasma and in lyophilized coagulation factor concentrates was reached at radiation doses as low as 1.5 and 0.5 Mrad, respectively. As derived from the first-order radiation inactivation curves, the radiosensitive target size of HIV was estimated to be 1 to 3 MDa; the target size of FVIII was estimated to be 130 to 160 kDa. Gamma radiation must be disregarded as a method for the sterilization of plasma and plasma-derived products, because of the low reduction of virus infectivity at radiation doses that still give acceptable recovery of biologic activity of plasma components.  相似文献   
8.
目的:跟踪测试优秀女子赛艇运动员比赛前后血乳酸、血尿素及血清肌酸激酶的变化,探讨女子赛艇运动员机体能量物质代谢和赛后疲劳恢复的特点。方法:选取2005-07/09湖北省水上运动中心优秀女子运动员14名,其中国家健将级运动员7名,国家一级运动员7名;平均年龄(22±4)岁,训练年限(4.1±1.4)年,身高(174.2±3.1)cm,体质量(68.6±4.7)kg。14名运动员分别于2000m划艇比赛当日晨空腹、赛前15min、赛后5min,1h及24h抽取指尖血60μL,进行血乳酸、血尿素、血清肌酸激酶检测。结果:14名运动员全部进入结果分析。①比赛前后运动员血乳酸水平的变化:运动员空腹血乳酸水平为(1.22±0.45)mmol/L,赛前15min为(2.89±0.49)mmol/L。赛后5min血乳酸浓度高达(11.51±1.72)mmol/L,与空腹水平比较差异有显著性意义(t=3.077,P<0.01)。赛后24h血乳酸浓度显著下降至(1.76±0.24)mmol/L,与空腹水平基本接近(t=0.027,P>0.05)。②比赛前后运动员血尿素水平的变化:与空腹血尿素水平比较,运动员赛后5min血尿素浓度明显升高[(5.45±0.47),(6.13±1.00)mmol/L;t=2.416,P<0.05]。赛后24h血尿素浓度下降至(5.94±0.85)mmol/L,仍高于空腹水平(t=2.682,P<0.05)。③比赛前后运动员血清肌酸激酶活性的变化:与赛前比较,运动员赛后5min血清肌酸激酶活性明显升高[(3.38±1.58),(6.13±3.25)nkat/L;t=4.968,P<0.01]。赛后1h血清肌酸激酶活性开始下降,至赛后24h与赛前基本相似(t=1.537,P>0.05)。结论:①赛后5min血乳酸、血尿素、血清肌酸激酶活性显著高于赛前,赛后1h血乳酸消除迅速,但仍未恢复到正常水平。提示赛艇是一种以糖酵解系统为主、无氧 有氧代谢混合型供能的运动项目。②赛艇比赛使酸性产物生成增多,血乳酸、血尿素、血清肌酸激酶可作为运动强度和机能恢复的指标。③赛艇比赛后至少24h内,机体处于蛋白质降解增强状态,建议恢复期增加饮食糖和蛋白质摄入量,以促进合成代谢,加快功能恢复过程。  相似文献   
9.
Alhagi, a plant genus from family Fabaceae, is widely distributed in many countries of Asia, Australia and Europe. Commonly known as camel thorn, Alhagi has many species famous for feed and folk medicinal uses. Different species of Alhagi such as Alhagi pseudalhagi, A. graecorum, A. sparsifolia, A. kirgisorum, A. maurorum, A. camelorum and A. persarum have been explored for their antioxidant potential and nutritive value along with various medicinal properties. A wide array of pharmacologically active secondary metabolites such as flavonoids, alkaloids (alhacidin and alhacin), steroids, pseudalhagin A, phospholipids and polysaccharides have been reported from different parts of Alhagi species. A broad range of biological activities such as antioxidant, cardiovascular, anti‐ulcer, hepatoprotective, antispasmodic, antidiarrheal, antinociceptive, antipyretic, anti‐inflammatory, anti‐rheumatic, antibacterial and antifungal have been ascribed to different parts of Alhagi. In addition, Alhagi plants are also valued as a rich source of digestible protein and important minerals. This review focuses on the medicinal applications and detailed profile of high‐value bioactive phytochemicals along with pharmacological attributes and therapeutic potential of these multi‐purpose plants. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
10.
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