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1.
BackgroundWe sought to identify treatment disparities existing prior to publication of the 2015 American Thyroid Association Management Guidelines in order to identify patients with papillary thyroid cancer (PTC) at risk for receiving inadequate treatment.MethodsPatients diagnosed with PTC from 2011 to 2013 were identified using Surveillance, Epidemiology and End Results database. High-risk disease was defined as T4, N1, or M1. Chi-square tests compared characteristics of patients with and without high-risk disease and characteristics of high-risk patients who did and did not receive radioactive iodine ablation (RAI). Likelihoods of having high-risk disease, of receiving RAI, and of cause-specific death were calculated using regression analyses.ResultsSample included 32,229 individuals; 7894 (24.5%) had high-risk disease. Mean age was 50.0 years, 24,815 (77.0%) were female, and 21,318 (66.2%) were white. Odds of high-risk disease were greater among males (OR:2.04; 95% CI:1.92–2.16), Hispanics (OR:1.67; 95% CI:1.56–1.79) and Asians (OR:1.49; 95% CI:1.37–1.62), and uninsured (OR:1.24; 95% CI:1.07–1.43), and lower among patients ages 45–64 (OR:0.57; 95% CI:0.53–0.60), and ≥65 years (OR:0.54; 95% CI:0.50–0.59), and Blacks (OR:0.46; 95% CI:0.40–0.53). Most (69.3%) high-risk patients received RAI. Odds of receiving RAI were lower among patients age ≥65 years (OR:0.67; 95% CI:0.58–0.77), uninsured (OR:0.52; 95% CI:0.41–0.67), or with Medicaid (OR:0.58; 95% CI:0.50–0.69). RAI use reduced the risk of cause-specific mortality (HR:0.29; 95% CI:0.18–0.47).ConclusionKnowledge of these treatment disparities will allow recognition of groups at risk for high-risk disease and receiving inadequate treatment.  相似文献   
2.
汕头卫生检疫局空港处对汕头航空口岸—宗入境二级货包的监测过程及对有关运输工作人员作了放射知识问卷调查。从中发现。运输单位货物存放设施落后。有关工作人员放射卫生知识欠缺,对放射污染可能造成的危害缺乏正确的认识。为此,笔者提出了自己的看法,以期对放射监测工作的进一步完善提供参考。  相似文献   
3.
4,7,13,16,21,24-Hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane (Kryptofix® 2.2.2) is used in the routine preparation of [18F]-labeled tracers employed in positron emission tomography (PET) imaging. Confirming the absence of Kryptofix® in radiopharmaceuticals is a quality control criterion required before they can be released for human use. Analysis of Kryptofix® levels using the iodoplatinate spot-test can be complicated by false-positive results due to nitrogen containing tracers and/or false-negative results caused by added stabilizers. To overcome this issue, we have developed a universal TLC method for the rapid and reliable determination of Kryptofix® levels in the wide range of fluorine-18 radiopharmaceuticals we prepare, including complex multi-component formulations.  相似文献   
4.
The position of the motornuclei projecting through the median (Mn) and ulnar (Ul) nerves to the cat distal forelimb has been investigated. Horseradish peroxidase (HRP) and fluorescent (Fl) compounds have been used as retrograde tracers. They were either injected into forelimb muscles or applied to the proximal end of transected forelimb nerves. Limb muscles that were not investigated were carefully denervated. The position and the architecture of the individual motornuclei were traced with HRP. The topographical relations between the nuclei were established with application of up to three different Fl compounds in the same animal. The Mn motoneurones had a bimodal distribution in the brachial spinal cord. The motoneurones to the pronator teres and flexor carpi radialis muscles were located in C7 and the other Mn motoneurones were located in C8 and Th1. In C7 the Mn motoneurones occupied a single representation area, which is located some distance medially of the lateral funiculus. In C8 and Th1 two Mn representation areas were found: A dorsal one that contacts the lateral funiculus and is located at the level of the central canal; a ventral one that is located ventrally in the ventral horn. The dorsal area is occupied by the motornuclei projecting to the intrinsic hand muscles and the ventral one by the nuclei projecting to the limb. The Ul motoneurones extend with an unimodal distribution from the caudal C7 to the caudal Th1 segments. They occupy a single, broad representation area. The dorsal part, which contacts the lateral funiculus, is located at the level of the central canal and harbours the nuclei to the intrinsic hand muscles. The other Ul nuclei are located ventromedially deep in the ventral horn. These results, together with those from the companion paper on the location of the deep radial motornuclei, provide important anatomical information for the investigation of the cat brachial enlargement.  相似文献   
5.
To assess the significance of diffuse cardiac activity (DCA) seen on In-111 labeled leukocyte scans, we reviewed 87 studies performed over the last 4 years. Inflammatory cardiac conditions were seen as frequently in patients with DCA (15%) as those without (7%, P=0.3). There was a higher ratio of RBC:WBC in the final WBC preparation in the false-positive DCA group than the true positive DCA and no DCA groups. False-positive studies showing DCA are most likely due to residual blood pool activity.Presented in part, 70th annual meeting, Radiological Society of North America, Washington D.C., 25 November 1984  相似文献   
6.
Summary An earlier retrograde double-labeling study in cat showed that up to 30% of the corticospinal neurons in the medial and anterior parts of the precruciate motor area represent branching neurons which project to both the spinal cord and the reticular formation of the lower brain stem. These neurons were found to be concentrated in the rostral portion of the motor cortex, from where axial and proximal limb movements can be elicited. In the present study the findings in the macaque monkey are reported. The fluorescent retrograde tracer DY was injected unilaterally in the spinal cord at C2 and the fluorescent tracer FB was injected ipsilaterally in the medial tegmentum of the medulla oblongata. In the contralateral hemisphere large numbers of single DY-labeled corticospinal neurons and single FBlabeled corticobulbar neurons were present. A substantial number of DY-FB double-labeled corticospinal neurons were also found, which must represent branching neurons projecting to both the spinal cord and the bulbar reticular formation. These neurons were present in: 1. The anterior portion of the cingulate corticospinal area in the lower bank of the cingulate sulcus; 2. The supplementary motor area (SMA); 3. The rostral part of precentral corticospinal area; 4. The upper portion of the precentral face representation area; 5. The caudal bank of the inferior limb of the arcuate sulcus; 6. The posterior part of the insula. In these areas 10% to 30% of the labeled neurons were double-labeled. The functional implications of the presence of branching corticospinal neurons in these areas is discussed.Abbreviations A nucleus ambiguus - AS arcuate sulcus - C cuneate nucleus - Cing. S. cingulate sulcus - corp. call. corpus callosum - CS central sulcus - Cx external cuneate nucleus - DCN dorsal column nuclei - dl dorsolateral intermediate zone - IO inferior olive - IP intraparietal sulcus - Lat. Fis. lateral fissure - LR lateral reticular nucleus - LS lunate sulcus - ML medial lemniscus - MLF medial longitudinal fascicle - mn motoneuronal pool - MRF medial reticular formation - Occ. occipital pole - P pyramid - PG pontine grey - PS principle sulcus - RB restiforme body - RF reticular formation - S solitary nucleus - SPV spinal trigeminal complex - STS superior temporal sulcus - Sup. Col. superior colliculus - TB trapezoid body - VC vestibular complex - vm ventromedial intermediate zone - III nucleus oculomotorius - VI nucleus abducens - VII nucleus, n. facialis - X motor nucleus n. vagus - XII nucleus hypoglossus Supported in part by grant 13-46-96 of FUNGO/ZWO (Dutch organisation for fundamental research in medicine)  相似文献   
7.
The present study was aimed at the anatomical identification in the rat of neurons of the lower brainstem reticular formation which give off axonal branches ascending bilaterally to more rostral structures and descending unilaterally to the spinal cord. Three fluorescent tracers were injected in one and the same animal. Fast Blue was injected in the midbrain tegmentum, in the termination areas and fiber bundles of the ascending reticular efferents; Evans blue was injected in the midbrain tegmentum on the other side; either Nuclear Yellow or Diamidino Yellow was injected in the white and gray matter of the upper cervical cord. All three populations of single-labeled cells, as well as double labeled either from the midbrain injections or from the ipsilateral injections in the mesencephalon and spinal cord, were intermingled in the medial reticular formation. Very few cells double labeled from the contralateral mesencephalon and ipsilateral spinal cord were also seen. However, the main finding of the present study was the visualization of triple-labeled cells. The latter were mainly located ipsilaterally to the injections in the spinal cord. The present results indicate that reticular cells give off divergent multiple branches descending to the ipsilateral spinal cord and ascending bilaterally to rostral centers.  相似文献   
8.
The architecture and musculotopic organization of the facial motor nucleus in the Cebus apella monkey (a New World primate) were investigated using histological techniques and a multiple labelling strategy, in which horseradish peroxidase‐conjugated neuroanatomical tracers (CTB‐HRP and WGA‐HRP) and fluorescent tracers were injected into individual facial muscles. The facial motor nucleus was formed by multipolar motoneurons and had an ovoid shape, with its rostrocaudal axis measuring on average 1875 µm. We divided the nucleus into four different subnuclei: medial, intermediate, dorsal and lateral. Retrograde labelling patterns revealed that individual muscles were innervated by longitudinal functional columns of motoneurons. The columns of the orbicularis oculi, zygomaticus, orbicularis oris, auricularis superior, buccinator and platysma muscles were located in the dorsal, intermediate, lateral, medial, lateral and intermediate subnuclei, respectively. However, the motoneuron columns of the levator labii superioris alaeque nasi muscle and frontalis muscle could not be associated with a specific subnucleus. The present results confirm previous studies regarding the musculotopic organization of the facial motor nucleus. However, we observed some particularities in terms of the relative size of each column in C. apella, which might be related to the functional and behavioral importance of each muscle in the particular context of this primate.  相似文献   
9.
The possibility of a direct projection from the perirhinal cortex (PER) to areas CA1 and subiculum (SUB) in the hippocampus has been suggested on the basis of tracer studies, but this projection has not unequivocally been supported by physiological studies. The demonstration of such a functional pathway might be important to understand the functioning of the hippocampal memory system. Here we present physiological and further anatomical evidence for such a connection between PER and the hippocampus. Electrical stimulation of PER in vivo evoked field potentials (EFPs) at the border area of CA1/SUB, consisting of a short latency and a longer latency component. Current source density analysis revealed that the sink of the short latency component was situated in the molecular layer of area CA1/SUB, while the longer latency component had its sink in the outer molecular layer of the dentate gyrus (DG). Anterograde tracer injections in PER showed labelled fibres in the border area of CA1/SUB, but anatomical evidence for a projection of PER to DG was not found. When synaptic transmission in the entorhinal cortex was partly blocked, the amplitude of the longer latency component of the recorded EFPs in the hippocampus was decreased while the short latency component was not affected, which suggests that the indirect pathway originating in PER is mediated through a synaptic relay in the entorhinal cortex. From the present results we conclude that information originating in PER reaches area CA1/SUB by parallel, direct and indirect, routes. The existence of this parallel organization appears to form an essential feature for the proper function of the medial temporal lobe memory system.  相似文献   
10.
A new method for intraperitoneal tumour targetting in ovarian cancer using biotinylated monoclonal antibodies (MoAb) and radioactive streptavidin is described. Fifteen patients with histologically documented ovarian carcinoma were injected intraperitoneally with 2 mg of biotinylated MoAb MOv18, followed 3–5 days later by 100–150 g of indium-111 streptavidin, at the specific activity of 280–370 MBq/mg in 500 ml of normal saline. No toxicity was observed. Tumours were imaged from 2 to 48 h after radioactivity injection by recording both planar and single photon emission tomography (SPET) data. All patients underwent surgery 1–8 days later (mean 3 days) after scanning. The resected tumour and normal tissue radioactivity were measured. On the day of surgery, the tumour to normal tissue ratio was 9:1 (range 3:1–30:1) and 45:1 (range 12:1–120:1) for intra- and extraperitoneal samples, respectively. The mean tumor to blood ratio was 14:1 (range 4:1–30:1). The injected dose (i.d.) per gram of tumour was 0.112 (range 0.01–0.3) for recurrences and 0.05 for primary tumour (range 0.005–0.2). Over 24–48 h 14% i.d. (range 8–18% i.d.) was found in the urine, 14% i.d. (range 629% i.d.) in the blood and 63% i.d. (range 56–70% i.d.) was still in the peritoneal cavity. These preliminary clinical data suggest that this two-step strategy may be superior to the conventional approach (radiolabelled antibodies) for intraperitoneal radioimmunolocalization and radioimmunotherapy of ovarian cancer. Offprint requests to: G. Paganelli  相似文献   
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