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81.
Lipodermatosclerosis: review of cases evaluated at Mayo Clinic.   总被引:1,自引:0,他引:1  
BACKGROUND: Lipodermatosclerosis describes bound-down, sclerotic skin involving the lower extremities. OBJECTIVE: Our purpose was to describe the demographic and clinical features of patients with lipodermatosclerosis. METHODS: This was a retrospective study of patients presenting to Mayo Clinic between 1976 and 1998 with a diagnosis of lipodermatosclerosis. RESULTS: Of 97 patients, 84 (87%) were women. Mean age was 62 years (range, 25-88 years). Mean body mass index was 34.3 (range, 17.8-71.5). Clinical signs were bilateral involvement in 44 patients (45%), induration localized to a discrete plaque in 49 (51%), erythema in 69 (71%), hyperpigmentation in 57 (59%), ulceration in 13 (13%), concomitant edema in 69 (71%), and varicosities in 55 (57%). Vascular studies performed on 72 patients showed abnormalities in 49: deep venous incompetence in 33 (67%), calf muscle pump abnormality in 19 (39%), abnormal pulsatility in 10 (20%), and obstruction in 1 (2%). CONCLUSION: Lipodermatosclerosis was associated with female sex, middle age, high body mass index, and venous abnormalities.  相似文献   
82.
Deep inspiration preceding Valsalva maneuver and rapid expiration immediately following it (DIVE) enhance venous blood flow on color Doppler flow imaging (CDI). The effect of DIVE was assessed in 115 consecutive lower extremity examinations. Of these, 95 or 115 (83%) had negative CDI sonograms, and 20 of 115 (17%) had partially (six of 115) or completely (14 of 115) occluding deep vein thrombosis. DIVE enhanced venous blood flow in 68% of the negative cases, resulting in transient venous distention, and/or more complete color filling, and/or greater spectral flow velocities. The 14 cases with completely occluding thrombi showed no response to DIVE. Six cases with partially occluding thrombi showed moderate to mild response to DIVE, with improved color delineation of the residual patent lumen around the thrombus. The authors conclude that DIVE facilitates deep venous CDI, especially when compression cannot be used to augment venous flow.  相似文献   
83.
A pilot study was conducted of the biological characteristics of the leukemia cells of newly diagnosed patients with poor prognosis acute myelogenous leukemia (AML). This study included measurements of the pretherapy proliferative rate of the leukemia cells in vivo, assessment of differentiation in vivo during remission induction therapy, and the level of expression of the fms, myc, and IL1β genes in pretherapy leukemia cells. Short cell cycle times were characteristic of the best prognostic category and were associated with a rapid reduction in marrow leukemia cells in cytosine arabinoside (araC)-sensitive patients. Expression of c-fms was associated with rapid reduction in marrow leukemia cells during araC therapy and with a successful treatment outcome. Expression of the IL1β gene was associated with short remissions. These studies suggest that when compared to newly diagnosed standard prognosis AML, the leukemia of poor prognosis patients is more likely to exhibit long cell cycle times, low levels of fms expression, and is less likely to be associated with myeloid differentiation during remission induction therapy. © 1993 Wiley-Liss, Inc.  相似文献   
84.
85.
Natural killer (NK) cells eliminate target cells infected with intracellular pathogens and tumor cells by employing the granule exocytosis and death receptor pathways. They also mediate the acute rejection of incompatible bone marrow cell (BMC) grafts. However, the cytotoxic mechanisms employed during acute BMC graft rejection are obscure. Throughout these studies, BMC graft rejection was compared between two inbred strains of mice: 129 mice, which apparently use perforin- and Fas-dependent cytotoxicity, and C57BL/6 (B6) mice, which are able to exploit perforin- and/or Fas-independent mechanisms. Using perforin-knockout (PKO) mice, we have determined that the granule exocytosis pathway can play a major role in NK cell-mediated rejection of allogeneic and MHC class I-deficient BMC, depending upon the genetic background of the recipient and the environmental housing conditions. Although the granule exocytosis pathway seems to be the most potent cytolytic mechanism of NK cell-mediated rejection, alternative perforin-independent mechanisms, such as death receptor-induced apoptosis, also exist. By preventing both perforin- and Fas-mediated interactions concurrently, we observed that 129 mice were impaired in mediating MHC class I-deficient BMC rejection, while B6 mice maintained strong rejection capacities. The administration of neutralizing TNF antibodies to B6PKO mice before challenging with Fas and MHC class I double-deficient BMC still did not reverse rejection. Thus, our studies reveal the relative importance of perforin-, Fas-, and TNF-based cytotoxicity in NK cell-mediated rejection of incompatible BMC.  相似文献   
86.
Plasma samples from patients with alcoholic cirrhosis were analysed for plasminogen activators and for inhibitors of the fibrinolytic system. Plasminogen activator activity was considerably increased in patients' plasma compared with normal. Immunochemical characterisation of these plasminogen activators showed that they included both tissue type and urokinase type plasminogen activator. The major inhibitor of plasmin, alpha 2-antiplasmin, was decreased in the patients, but no evidence for the generation of plasmin was found.  相似文献   
87.
Summary: Linear unsaturated nylons 6 u18 and 18 u18 have been made containing a double bond in the center of the diacid segment with potential for additional functionalization. Solution state NMR showed the presence of a small portion of cis amide units. Solid state NMR verified the presence of the double bond in the bulk, and that the polyamides were present in the α‐crystalline form. Thermal stability was comparable to linear saturated nylons, and the melting and crystallization temperatures of the unsaturated nylons were lower compared to the saturated analogs.

DSC heating and cooling thermograms for nylons 6 u18 and 18 u18.  相似文献   

88.
89.
A novel papillomavirus was cloned from hyperkeratotic cutaneous lesions of a Persian domestic cat. The Felis domesticus papillomavirus (FdPV-1) genome counts 8300 bp and has a typical genome structure with an early region (E1, E2, E4, E6, E7), a late region (L1, L2), and a noncoding upstream regulatory region (URR or NCR1) between the end of L1 and the beginning of E6. The FdPV-1 also shows an unusual second noncoding region (NCR2) of 1.3 kb, situated between the end of E2 and the beginning of L2. This NCR2 is uniquely related to a similar region in the canine oral papillomavirus (COPV). Phylogenetic analysis places FdPV-1 together with COPV, the cottontail rabbit papillomavirus, human papillomavirus type 1 (HPV-1), and HPV-63 in the group of the benign cutaneous papillomaviruses. The position of FdPV-1 in the phylogenetic tree allows us to hypothesize that already in an early phase of the papillomavirus molecular evolution, a split occurred into viruses with a dual tropism primarily for cutaneous epithelia but also secondarily for mucosal surfaces, and viruses with a specific monotropism for mucosal surfaces. The close relationship between FdPV-1 and COPV, and between their Canidae and Felidae hosts, supports the hypothesis that papillomaviruses have speciated and coevolved together with their hosts throughout vertebrate evolution. A papillomavirus mutation rate of 0.73 to 0.96 x 10(-8) nucleotide substitutions per base per year was calculated.  相似文献   
90.
The goal of this study was to identify chromosomal regions likely to contain susceptibility alleles for early-onset obsessive-compulsive disorder (OCD). A genome scan was done in 56 individuals from seven families ascertained through pediatric OCD probands; 27 of the 56 subjects had a lifetime diagnosis of definite OCD. Denser mapping of regions on chromosomes 2, 9, and 16 was subsequently done with those subjects and ten additional subjects from the largest family in the study. Direct interviews were completed with 65 of the 66 genotyped individuals. Relatives were interviewed blind to proband status. Of the 65 interviewed individuals, 32 had a lifetime diagnosis of definite OCD. Three of the seven probands had a history of Tourette disorder. Two of the 25 relatives with OCD had a tic history, whereas none of the 33 relatives without OCD had tics. The genome scan consisted of 349 microsatellite markers with an average between-marker distance of 11.3 centiMorgan (cM). Fine mapping was done with 24 additional markers at an average spacing of 1.6 cM. Parametric and nonparametric linkage analyses were conducted using GENEHUNTER(+). The maximum multipoint LOD score with a dominant model was 2.25 on 9p. However, with fine mapping and additional subjects, that LOD score decreased to 1.97. The maximum multipoint nonparametric LOD* score was 1.73 on 19q. The maximum multipoint LOD score with a recessive model was 1.40 on 6p. The results provide suggestive evidence for linkage on 9p and identify regions requiring further study with much larger samples.  相似文献   
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