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11.
Specific pathogen-free lambs were exposed to an aerosol of ovine adenovirus type 4 (OA4). The virus replicated both in the respiratory and the alimentary tracts, and was recovered from one lamb 80 days after inoculation. Although infection with OA4 did not produce clinical disease, it appeared to be associated with the development of pulmonary oedema in approximately half of the infected lambs. The oedema was mainly perivascular, but in severe cases was present in alveoli and bronchioles. Small accumulations of mononuclear cells were present around bronchioles and small blood vessels, but inclusion bodies were not detected. 相似文献
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Osteosarcomatosis 总被引:10,自引:0,他引:10
Hopper KD; Moser RP Jr; Haseman DB; Sweet DE; Madewell JE; Kransdorf MJ 《Radiology》1990,175(1):233-239
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized. 相似文献
14.
It has been shown previously that the antero-inferior cortex is subjected to maximal tensile stress during a fall onto the
greater trochanter. We have recently shown that in cases of femoral neck fracture, cortical thinning and porosity is greatest
in the anterior and antero-inferior region of the femoral neck. To investigate whether this is due to increased remodeling,
we have quantified surface-based parameters associated with Haversian remodeling in femoral neck biopsies from women with
intracapsular hip fracture and post-mortem controls. Cryostat sections of chilled biopsies were reacted for either tartrate-resistant
acid phosphatase (TRAP) or alkaline phosphatase (ALP) activity. Proportions of active canals were determined in each quadrant
(inferior, anterior, superior, posterior) of the femoral neck. The biopsies were then embedded in methacrylate to permit histomorphometry
using Goldner’s and Solochrome sections. In the cases there was no significant increase in the proportion of canals undergoing
remodeling in the cortex as a whole (p = 0.846), but the regional distribution of remodeling was markedly different from that in the controls. In the anterior cortex,
the proportion of canals undergoing remodeling was increased by 56% (p = 0.0087); in contrast there was a relative decrease of 35% in the superior region (p = 0.0047). In the anterior cortex of cases there were 76% and 42% increases in the proportions of eroded (p = 0.019) and osteoid-bearing (p = 0.041) canals, respectively. In the superior region, the decrease in the proportion of remodeling sites was due to a marked
decrease in canals with an osteoid surface (51%; p = 0.0031). Covariance analysis with cortical porosity as the dependent variable showed that porosity was significantly dependent
on the regional distribution of eroded (p = 0.033) but not on the distribution of forming (p = 0.153) canals (R
2adj = 0.51). Cellular levels of TRAP and ALP were significantly elevated in the anterior region of cases compared with the
controls (TRAP 55%, p = 0.006; ALP 36%, p = 0.003). For the posterior and inferior regions there were no marked differences in cellular TRAP and ALP levels compared
with control values. These data show that the increased cortical thinning and increased porosity we have previously observed
in the anterior cortex in cases of hip fracture are associated with increased indices of Haversian remodeling. These findings
are consistent with the hypothesis that, in cases of hip fracture, remodeling imbalance in the anterior cortex is a continuing
process up to the time of fracture and is due to increased osteoclastic cellular activity associated with an osteoblastic
response that is inadequate to prevent bone loss.
Received: 16 November 1998 / Accepted: 17 February 1999 相似文献
15.
Two social workers attached to a health centre organised a group for single and separated parents with problems, as an addition to medication and individual treatment available. This paper covers the selection, aims and structure of the group and examines the content of the meetings. It concludes that this is a viable method for alleviating the social isolation and anxiety of lone parents beyond their participation in groups. 相似文献
16.
Influence of inhaled corticosteroids on growth: a pediatric endocrinologist''s perspective 总被引:7,自引:0,他引:7
DB Allen 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(2):123-129
Given the increasing advocacy for the use of inhaled corticosteroids as a treatment of choice for persistent asthma, growing numbers of children are being exposed to the possible growth-suppressing effects of glucocorticoids. Recent evidence strongly suggests that, when consistently administered at moderate doses, inhaled corticosteroids (IC) are capable of slowing growth in children. Whether such growth suppression would persist and ultimately affect final adult height remains unknown. Therapeutic goals which aim for uninterrupted inflammatory disease control rather than periodic symptom control may increase the occurrence of growth failure in children treated with IC. In this article, current information about the mechanisms of growth suppression by glucocorticoids and the effects of IC on growth is reviewed, and recommendations for designing studies to investigate the effects of drugs on growth are presented. 相似文献
17.
van Kranen HJ; van Iersel PW; Rijnkels JM; Beems DB; Alink GM; van Kreijl CF 《Carcinogenesis》1998,19(9):1597-1601
The variation in colorectal cancer (CRC) incidence worldwide strongly
suggests a role for dietary influences. Based on epidemiological data,
protective effects of vegetables and fruit intake on CRC are widely
claimed, while other data indicate a possible increased CRC risk from
(higher) dietary fat intake. Therefore, we have investigated single and
interactive effects of dietary fat and a vegetable-fruit mixture (VFM) in
the ApcMin mouse, a mouse model for multiple intestinal neoplasia. In this
study, four different diets (A-D) were compared, which were either low in
fat (20% energy diets A/B) or high in fat (40% energy diets C/D). In
addition, 19.5% (wt/wt) of the carbohydrates in diets B and D were replaced
by a freeze-dried VFM. The diets were balanced so that they only differed
among each other in fat/carbohydrate content and the presence of specific
plant-constituents. Because the initiation of intestinal tumors in ApcMin
mice occurs relatively early in life, exposure to the diets was started in
utero. Without the addition of VFM, mice maintained at a high-fat diet did
not develop significantly higher numbers of small or large intestinal
adenomas than mice maintained at a low-fat diet. VFM added to a low-fat
diet significantly lowered multiplicity of small intestinal polyps (from
16.2 to 10.2/mouse, 15 animals/group), but not of colon tumors in male
ApcMin mice only. Strikingly, addition of VFM to female mice maintained on
a low-fat diet and to both sexes maintained on a high-fat diet
significantly enhanced intestinal polyp multiplicity (from 16.5 to 26.7
polyps/mouse). In conclusion, our results indicate that neither a lower fat
intake nor consumption of VFM included in a high-fat diet decreases the
development of polyps in mice genetically predisposed to intestinal tumor
development.
相似文献
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