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81.
82.
Franklin Patricia D. Zheng Hua Bond Christina Lavallee Danielle C. 《Quality of life research》2021,30(11):3171-3178
Quality of Life Research - New informatics tools can transform evidence-based information to individualized predictive reports to serve shared decisions in clinic. We developed a web-based system... 相似文献
83.
84.
Jaan Noolandi Mark C. Peterman Philip Huie Christina Lee Mark S. Blumenkranz Harvey A. Fishman 《Biomedical microdevices》2003,5(3):195-199
Electronic chips that provide a patterned stimulus to cells in the retina may provide a viable treatment for age-related macular degeneration. A surrogate MEMS device, in the form of a print-head from a desktop printer, has been used to eject a pattern of neurotransmitters (bradykinin) onto living rat pheochromocytoma (PC12) cells. Fluorescent calcium imaging was used to measure the patterned stimulation of individual cells. The chemical stimulation of cells by directed microfluidic delivery may have applications in retinal prosthetic devices, and in other prosthetic implants in the nervous system. 相似文献
85.
P53 overexpression as an indicator of overall survival and response to treatment in osteosarcomas 总被引:5,自引:0,他引:5
Pápai Z Féja CN Hanna EN Sztán M Oláh E Szendrôi M 《Pathology oncology research : POR》1997,3(1):15-19
The p53 gene located at chromosome 17pl3 is found to be altered (allelic loss or other mutation) in multiple human cancers,
including osteosarcomas. The mutated gene produces a protein with a prolonged half-life thus rendering it detectable by conventional
immunohistochemistry. We examined the correlation between p53 expression and clinical prognosis as well as response to therapy.
Twentyone patients with previously untreated and histologically verified highly malignant osteosarcoma were used for this
study. Biopsy material taken both prior to the start of COSS 91 protocol and at the time of surgery (ten weeks later) was
examined for alterations in p53 protein expression and drug resistance. Two patients who had strong (+++) p53 protein expression
and three others who became positive during the chemotherapy had significantly worse prognosis (all of them died within one
year) than those who showed no p53 expression both at biopsy and after chemotherapy (all 11 patients are alive, average follow-up
time: 3.5 years). All patients who showed any kind of positive p53 protein expression on initial biopsy were non-respon-ders
to chemotherapy. In contrast, 69% (9 out of 13) of those who exhibited no p53 expression on initial biopsy were responders
or intermediate responders to chemotherapy. We concluded that p53 expression may be a useful prognostic factor in osteosarcomas.
The direct correlation between p53 positive expression and resistance to therapy can help in identifying patients who are
in need of a more vigorous or different chemotherapeutical protocol. 相似文献
86.
There is controversy over whether isometric contraction of the forearm evokes vasoconstriction or vasodilatation in the muscles of the contralateral forearm. In the present study we have investigated in normal man, the effects of isometric contraction of one arm at 75, 50 and 25% maximum voluntary contraction (MVC) on arterial pressure, heart rate, blood flow and vascular resistance of the contralateral forearm and on electromyographic (EMG) activity recorded from that same arm with sensitive, surface electrodes.When EMG activity was not being recorded from the resting arm, isometric contraction of the contralateral arm for 2 min evoked increases in arterial pressure and heart rate whose magnitudes were graded with % MVC and an increase in forearm blood flow and a decrease in forearm vascular resistance at 75, 50 and 25% MVC, indicating vasodilatation. Further experiments in which EMG activity was recorded from the resting arm demonstrated that the decrease in forearm vascular resistance evoked by 75% MVC was associated with a substantial increase in EMG activity of the extensor and flexor muscles of that arm. By contrast, when forearm contraction was performed at 75% MVC whilst subjects viewed the EMG activity in the resting arm on an oscilloscope and kept EMG activity minimal, vascular resistance increased in that arm, indicating vasoconstriction. Further, when subjects performed contraction at 25% MVC whilst showing minimal EMG activity in the contralateral arm, vascular resistance in that same arm increased (from 78 ± 16 to 124 ± 29 mmHg/ml/min/100 ml tissue). These results are discussed in relation to those of previous studies. We propose, that in normal man, isometric contraction of the forearm evokes primary vasoconstriction in the muscles of the contralateral forearm, but that this response may be overcome by muscle vasodilatation occurring secondary to unintended muscle contraction or as part of the alerting response to acute stress. 相似文献
87.
Although many workers have appreciated the striking cytologic and neurochemical similarities of neostriatum, accumbens and olfactory tubercle, a compelling case for regarding these areas as territories in a striatal complex awaited the arguments made by Heimer and his colleagues based on their investigations of connections. A number of recent papers support this viewpoint and extend it with the characterization of three accumbal subterritories: core, shell and rostral pole. The case for separate classifications of systems traversing the accumbens has become more compelling with each study that demonstrates connectional, cytoarchitectural and neurochemical specificity conforming to the boundaries separating the core and its downstream targets from the shell and its projection fields. Furthermore, its apparent composite of core-like and shell-like characteristics distinguishes the rostral pole as yet another unique subterritory. Differences in compartmental organization distinguish the accumbens and neostriatum. The available data are consistent with the periventricular and rostrolateral enkephalin-rich zones being ventralmost parts of the neostriatal patch and matrix compartments, respectively. The accumbal cell cluster compartment, on the other hand, appears to be a separate entity, with connectional and neurochemical features that are dissimilar to both patch and matrix of neostriatum. Boundaries between the accumbens and caudate-putamen remain elusive, and the point of view that such boundaries do not exist but, rather, are represented by "transition zones" must to a large degree reflect the reality. Likewise, it is important to acknowledge that the boundaries between accumbal subterritories are not necessarily distinct or observed faithfully by all of the afferent systems. "Transition zones" appear to be particularly significant organizational features in rostral and lateral parts of the accumbens. Interestingly, histochemically distinct cell clusters tend to be numerous in boundary regions between adjacent territories and subterritories. The predominant organizational pattern appears to be one in which the core, shell and rostral pole engage different forebrain systems that possibly subserve entirely different functions mediated by distantly related mechanisms. In this regard, it is of paramount interest that the processing of information conveyed to the accumbens by diverse cortical and subcortical inputs occurs within distinct and perhaps very different dopaminergic environments in the core, shell and rostral pole (e.g., see Refs 24, 34, 90, 110). 相似文献
88.
Antineoplastic effects of partially HLA-matched irradiated blood mononuclear cells in patients with renal cell carcinoma. 总被引:11,自引:0,他引:11
Roger K Strair Dale Schaar Daniel Medina Mary B Todd Joseph Aisner Robert S DiPaola Jacqueline Manago Beth Knox Amanda Jenkinson Rachelle Senzon Christina Baker Dudek Liesel Marie Ciardella Mercy Kuriyan Arnold Rubin Edmund C Lattime 《Journal of clinical oncology》2003,21(20):3785-3791
PURPOSE: Vaccines, cytokines, and other biologic-based therapies are being developed as antineoplastic agents. Many of these agents are designed to induce an autologous immune response directed against the malignancy. In contrast, hematopoietic stem-cell transplantation is being developed as a form of allogeneic immunotherapy. This study tests the tolerance and antineoplastic activity of sequential infusions of partially HLA-matched allogeneic blood mononuclear cells (obtained from relatives) when administered outside of the context of a hematopoietic stem-cell transplantation. The cells are irradiated to prevent graft-versus-host disease. PATIENTS AND METHODS: Fifteen patients with relapsed or refractory malignancies for which no standard therapy was available were enrolled onto a clinical trial designed to assess the tolerability and antineoplastic effects of irradiated partially HLA-matched blood mononuclear cells obtained from relatives. RESULTS: There was disease regression in three patients with metastatic renal cell carcinoma during treatment. There was disease progression in six patients with metastatic renal cell carcinoma and two patients with metastatic melanoma during treatment. There was no change in disease state in several other patients. CONCLUSION: Irradiated allogeneic blood mononuclear cells administered outside the context of hematopoietic stem-cell transplantation may induce disease responses in patients with relapsed or refractory malignancies. Transfusion of irradiated allogeneic blood mononuclear cells should be developed further as a novel therapeutic antineoplastic approach. 相似文献
89.
Rachael McEwing Christina Hayward Margaret Furness 《Journal of Medical Imaging and Radiation Oncology》2003,47(2):101-110
Foetal abdominal cysts are frequently found on routine antenatal ultrasound. Various sonographic features might help in their differential diagnosis. However, a definitive diagnosis is often not made until postnatal life, and detection of an intra‐abdominal cyst antenatally rarely alters obstetric management. A review of possible causes of a foetal abdominal cyst is presented. 相似文献
90.
Panos K. Prassopoulos Christina A. Giannakopoulou Eleni G. Apostolaki Nickolas Z. Charoulakis Nickolas C. Gourtsoyiannis 《Pediatric radiology》1998,28(8):605-607
Psoas abscess in children, and especially in neonates, is an uncommon condition which is difficult to diagnose clinically.
The US, CT and MR findings of a psoas abscess in a neonate, which extended to the thigh, are reported. Imaging was helpful
in revealing the abnormality, in demonstrating its extension and in determining its nature. The child was treated conservatively
and the abscess resolved, leaving atrophy of the psoas muscle.
Received: 24 June 1997 Accepted: 9 January 1998 相似文献