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891.
Changing patterns of c-fos induction in spinal neurons following thermal cutaneous stimulation in the rat 总被引:4,自引:0,他引:4
Patterns of neuronal activity in the lumbar spinal cord of the anaesthetized rat were mapped by immunocytochemical localization of the c-fos gene product, Fos protein, at different timepoints following brief noxious stimulation of one hindpaw (20 s immersion in water at 52 degrees C). After 2 h, Fos-immunoreactive neurons were seen mainly in the superficial laminae of the ipsilateral dorsal horn, with maximum somatotopic organization in lamina II. Subcutaneous injection of dilute formalin produced a similar pattern of immunostaining at 2 h, with a greater proportion of Fos-positive neurons in laminae III-VIII than with heat. With a survival time of 8 h following formalin injection, Fos immunoreactivity was virtually absent from the spinal cord. Eight hours after heat stimulation, however, the superficial pattern had given way to the appearance of a population of immunoreactive cells in the deeper laminae. The pattern of this "second wave" of heat-induced Fos-positive cells had a marked contralateral component, and was still present after 24 h, having become even more diffuse and symmetrical. The number of Fos-positive cells seen at 8 h was increased by local anaesthetic blockade of the peripheral nerve after stimulation, and reduced by continuous barbiturate anaesthesia. These findings suggest that the early stages of thermal injury trigger a complex pattern of molecular events within the spinal cord, which are initially monosynaptic and closely related to primary afferent terminal depolarization, and in the longer term the result of an induced pattern of synaptic activity set up within the spinal cord. 相似文献
892.
A case of nonvenereal acquisition of syphilis in a 2.5 year old male Indian child is discussed. The child had condylomata lata around the anal and prepuce, with enlarged nontender inguinal lymph nodes. Treponema pallidum was found in material from both lesions, and both the VDRL and FTA-Abs tests were positive. There were not other significant findings. The patient was treated with 1.2 million units of benzathine penicillin im, and the lesions resolved in 7 days. This boy had been raised by his grandparents since the age of 6 months. They did not report a primary syphilitic lesion, but the grandmother did admit to kissing the child's genitals, a custom of affection toward babies in the area. Sexual abuse was denied. The grandmother had a buccal lesion, which showed a Treponema on darkfield microscopy, and she had positive syphilis serology. both grandparents were also treated. 相似文献
893.
Non-linearity of neoplastic conversion induced in rat liver by low exposures to diethylnitrosamine 总被引:5,自引:0,他引:5
Neoplastic conversion induced in rat liver by diethylnitrosamine(DEN) was quantified by measuring preneoplastic and neoplasticlesions over a 34 week period in the beginning of which thecarcinogen was given at three dose levels and two dose ratesfor the first 10 weeks, after which animals were maintainedfor 24 weeks with either no further exposure or were fed phenobarbital(PB) to promote neoplastic development of cells converted byDEN. DEN was injected s.c. inmale F344 rats at weekly or biweeklyintervals for total doses of 1, 2 or 4 mmol/kg body wt and thenthe rats were maintained on basal diet alone or diet containing0.05% PB. At the end of exposure, DEN had produced a dose-relateddecrease in centrilobular glutamine synthetase-expressing (GS+)hepatocytes which is indicative of mild cytotoxicity. All dosesinduced foci that were 相似文献
894.
We present 2 cases of polymicrobial catheter sepsis in patients with long term central venous catheters who were receiving home parenteral nutrition. Both patients were generally unwell with haemodynamic instability. Attempts at catheter salvage by combined antibiotic and fibrinolytic administration through the central line were unsuccessful and resulted in patient deterioration. Catheters were removed in both patients. We conclude that catheter salvage should be considered very carefully in patients with polymicrobial catheter sepsis and there should be a low threshold for catheter removal in these cases. 相似文献
895.
The randomized response survey technique appears to be suitable for studies of sensitive sexual behaviors, particularly in AIDS-related research. However, existing methods provide only estimates of group statistics, not of individual information. Additionally, the popular "unrelated question" approach requires the knowledge of the parameters of the unrelated question. In this article, a variation of the unrelated-question method is suggested for use. Specifically, it is suggested that the unrelated question be one to which the response is known to be "yes." Through this "controlled" approach, the raw data become a direct linear transformation of the response to the sensitive question, and thus can be used directly in regression and other analyses at the individual score level. The estimation of the parameters for the unrelated question is not necessary and the hesitation to provide a "yes" response found in the "forced choice" method is minimized. 相似文献
896.
Uebelhart D Thonar EJ Pietryla DW Williams JM 《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》1993,1(3):185-192
To measure urinary levels of two pyridinium cross-links of collagens at various times, rabbits were injected in the left knee with 0.2 mg (N = 11) or 2.0 mg chymopapain (N = 11). Urinary levels of the bone-specific deoxy-pyridinoline cross-link and of the hydroxylysyl pyridinoline cross-link, found in large amounts in articular cartilage and bone, were measured by high performance liquid chromatography (HPLC). The urinary levels were correlated with histological evidence of progressive articular cartilage destruction in animals injected with 2.0 mg chymopapain and of successful repair in rabbits injected with the lower dose. Rabbits injected with 2.0 mg chymopapain showed a very large increase in urinary levels of deoxy-pyridinoline during the first 30 days after the injection. This rise was not seen in animals injected with the lower dose. A rise in urinary level of the hydroxylysyl pyridonline cross-link was observed in all rabbits but was more pronounced and lasted longer in animals receiving the higher dose. The failure of rabbits injected with 2.0 mg chymopapain to repair the damaged articular cartilage was strongly associated with a marked increase in the catabolism of the bone-specific deoxy-pyridinoline cross-link and to a lesser extent with the catabolism of the hydroxylysyl pyridinoline found in bone and in articular cartilage. 相似文献
897.
D. Gwyn Williams 《Pediatric nephrology (Berlin, Germany)》1993,7(3):303-311
Despite a prodigious amount of work on the physiology of IgA production in man, and many studies on the immunopathology of IgA nephropathy, ranging from the immunogenetics to the immune response to chemical characteristics of the IgA, we are hardly any nearer to defining the pathogenesis of this disease. One of the main changes in our understanding has been to recognise that the bone marrow, now known to produce normally one-third of the body's IgA, overproduces this immunoglobulin in IgA nephropathy. This alters the previous notion that IgA nephropathy was due simply to IgA production in the mucosa, although a mucosal component is not excluded. Certain characteristics of the IgA in the diseased kidney and the circulation have been defined: it is of subclass IgA1 and has a higher proportion of light chains and negative charge than in normal subjects. The specificities of the IgA, either in the kidney or in complexes, have not helped to clarify the pathogenesis. They have been found for a wide range of endogenous and exogenous antigens, suggesting that the antibody activity represents polyclonal B cell activation. These findings have not helped to confirm the prevailing theory that IgA nephropathy is an immune complex disease. Other theories put forward are that IgA nephropathy is an autoimmune disease, glomerular components or IgA itself being among the candidate antigens, or that there is primary dysregulation of the IgA immune system. At this stage of development in our understanding of this common nephropathy, it is important to guard against the assumption that idiopathic IgA nephropathy is one disease and is the result of a single pathogenetic mechanism. 相似文献
898.
899.
New "contingent" compensation programs tailored to the hospital work unit provide employees with incentive payments for outstanding performance that augment--or replace--the annual merit increase. 相似文献
900.
Warrick LH Christianson JB Williams FG Netting FE 《Hospital & health services administration》1990,35(4):505-524
This article contains the initial findings of an ongoing evaluation of a hospital-based coordinated care demonstration. The goal of the demonstration is to investigate the appropriateness and feasibility of providing hospital-based case management services for extended periods to elderly individuals living in the community. The rationale for the demonstration is reviewed, and the structure of each participating hospital's coordinated care program is described. Data are presented on the characteristics of clients served by the programs during the first six months of the demonstration. The factors that influenced implementation and early operations of these programs are analyzed, and their implications for hospital managers are discussed. 相似文献