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81.
BACKGROUND: The importance of the size of the primary tumor in lymphomas and its size after treatment is still uncertain. Assuming a prognostic relevance, an assessment of tumor volume before and after induction of chemotherapy has been performed in the pediatric Hodgkin's disease study (HD-90). Since an exact CT-scan-based volumetric tumor assessment is time-consuming and in some centers not possible, the tumor volume is often estimated based on simple geometric approximations. Aim of this study was the development of an easy to apply and nearly exact model of volume estimation compared to CT-scan-based tumor volume measurements. MATERIAL AND METHODS: Thirty computed tomographies (CT) of mediastinal Hodgkin lymphomas of children aged 5 to 16 years have been examined. The CT scans were digitalized using a CCD camera combined with a frame grabber. Applying the Global Lab image software, the true tumor volume was determined excluding local organs, which did not belong to the lymphoma. Subsequently, volumes were assessed using simple geometric models (block, ellipsoid, octaeder) by using the maximum diameters of the tumor. The differences between the volume of the geometric models and the true volume, based on the CT scan evaluation, were compared. RESULTS: The maximum diameters of a tumor can be used to calculate its volume based on simple geometric models. The model "block" overestimates the volume by 89 to 268%. The model "ellipsoid" overestimates the volume on average by 29%. The model "octaeder" underestimates the volume on average by 18%. A division of the block volume by 2.3 approximated the geometric closest to the true volume: the average volume was overestimated by 2% in tumors with a volume larger than 20 ml. No model was sufficient to approximate tumors with a volume of less than 20 ml. CONCLUSIONS: For the estimation of tumor volumes in mediastinal Hodgkin lymphomas exceeding 20 ml, the formula "block/2.3" results in the closest approximation compared to the true volume. In the course of clinical studies it might be helpful to apply this formula to determine the prognostic relevance of the tumor size and its development under therapy.  相似文献   
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A case report of embryonal rhabdomyosarcoma originating from the cervix in a 3-year-old girl is presented and a brief review of the literature on this topic given. The histopathology of the tumor is discussed and the effectiveness of a less aggressive surgical approach and chemotherapy is demonstrated in this particular case.  相似文献   
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Allospecific T lymphocyte clones with different functions were generated from spleen cells of C 57/Bl6 mice following sensitization in vitro by a one-way mixed lymphocyte culture (MLC) with irradiated DBA/2 spleen cells. The clones were propagated in vitro in the presence of interleukin 2 (IL 2) and restimulation with stimulator cells. In these clones Cyclosporin A (CSA) was tested for its suppressive effect on different T lymphocyte functions. The antigen-dependent proliferation of a helper clone (HTL) was totally inhibited by 50 ng/ml CSA. Proliferation induced by simultaneous administration of antigen and IL 2 was partially suppressed in all helper and cytotoxic clones (CTL). The IL 2-driven proliferation in the absence of antigen was also suppressed between 25-70% by the immunosuppressive drug. Secretion of macrophage activating factor (MAF) and interferon (IFN) by HTL and CTL in response to antigen or mitogen was reduced dose dependently by CSA. Concentrations of 50 ng/ml CSA diminished lymphokine secretion to approximately 10% of controls, also when excess IL 2 was present. Cytotoxicity, previously described to be insensitive to the drug, could be suppressed by 50 ng/ml CSA to a various extent, from 40-70%, in different cytotoxic clones when the effector cells were preincubated with CSA for 1 h or more. Conclusively, the data suggest that CSA interferes generally with the activation of T lymphocyte clones.  相似文献   
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The purpose of this review is to analyse nature, degree and consequences of attentional biases in patients with borderline personality disorder based on existing literature. The clinical importance of these phenomena in patients with borderline personality disorder is strengthened and the link between theoretical models, empirical findings and therapeutic interventions is elaborated. This link between selective attention and borderline personality disorder is demonstrated on the basis of studies, which indicate a context between borderline pathology, affective disorders, anxiety disorders, and attention-deficit/hyperactivity disorders and also give evidence to neuropsychological deficits in patients with borderline personality disorder. The present article comparatively describes three theoretical models of borderline personality disorder and their possible links to attentional biases. The dialectical behavior approach postulates a pronounced attentional narrowing to emotional stimuli in connection with deficits regarding affect regulation. The cognitive approach assumes that rigid dysfunctional schemata initiate a cognitive-emotional circuit, which leads to a reinforcement of the symptomatology as a result of a biased perception and memory. Additionally the present article specifies the trauma approach which emphasizes the relation between borderline pathology and childhood trauma with recourse to theories of attentional biases in patients with traumatic experiences. Preliminary empiricial findings suggest that patients with borderline personality disorder demonstrate a general attentional bias for any emotional negative stimuli and not a selective attentional bias to borderline-specific stimuli. Further studies should clarify, whether therapeutical interventions with the aim to influence attentional processes represent a useful complement to established therapies in patients with borderline personality disorder.  相似文献   
88.
Approximately 3%–6% of all newborn infants require some form of resuscitation at birth, making neonatal resuscitation one of the commonest medical interventions. An internationally agreed consensus statement and various guidelines advise how newborn infants should be resuscitated and suggest equipment to use. The aim of this study was to compare the current standard of neonatal resuscitation in Austria with the neonatal resuscitation guidelines published in 2005. A questionnaire was sent to Austrian neonatal units with delivery rooms. The questionnaire evaluated the use of positive pressure ventilation devices, pulse oximetry, laryngeal mask, oral (Guedel) airway, oxygen blenders, use of supplementary oxygen in term infants, CO2 detectors and polyethylene wrapping for infants ≤ 28 weeks. All 20 neonatal units contacted answered the questionnaire. The initial oxygen concentration during resuscitation of term infants ranged between 21% and 100%. A total of 17 (85%) departments used oxygen blenders, the others a flow meter. Pulse oximetry was used in 20 (100%) departments, nine (45%) used a self-inflating-bag and a T-piece device. Two departments used either the self-inflating or the T-piece device and none used the flow-inflating bag. An oral airway (Guedel) was used in 10 (50%) and a laryngeal mask in eight (40%) departments. CO2 detectors were in use in six (30%) and polyethylene wrapping in 11 (55%) departments. This survey shows that, in line with the international trend, a wide-ranging variety of equipment is used also in Austria, reflecting the lack of data on neonatal resuscitation.  相似文献   
89.
PURPOSE: The purpose of the study was to examine the corneal inflammatory reaction and Langerhans cells with confocal microscopy after metal foreign body removal. METHODS: Corneal metal foreign body was removed from 9 eyes of 9 consecutive patients 12.1+/-13.6 (4 to 72) hours after superficial angle grinder injury. Both eyes were examined with the Heidelberg Retina Tomograph II (HRT II) Rostock Cornea Module. Morphology and density of epithelium, nerves, metal deposits, keratocytes, endothelium, and Langerhans cells were compared to the uninjured fellow eyes (controls). RESULTS: Irregularity and partially missing superficial epithelium was found in all cases. Around the area of injury prolonged basal and wing epithelial cells were found in all eyes. The basal epithelium density is lower than in the control eye (p=0.043). Density of Langerhans cells (68.1+/-24.2/mm2) was increased in the epithelium, compared to controls (35.2+/-21.8/mm2, p=0.012). Keratocyte and endothelium densities were not different from that of controls. Some keratocytes showed signs of activation and the inhomogeneous background reflectivity revealed extracellular matrix alterations. Inflammatory reaction was observed up to260 micronm depth. The metal foreign body particles had high reflectivity and irregular edge. CONCLUSIONS: In vivo confocal microscopy provided additional information to biomicroscopic signs such as epithelial damage and inflammation. It showed the effects of metal foreign bodies in the cornea: nerve damage and Langerhans cell density increase. Langerhans cells seem to play an important role in the inflammatory response after corneal foreign body injuries.  相似文献   
90.
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