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61.
Summary Parasternal two-dimensional and Doppler echocardiography were compared with angiographic, surgical, and postmortem data in 213 patients with various forms of congenital heart disease for its accuracy in determining patency and anatomy of the ductus arteriosus (DA). The age range of the examined patients was from 1 day to 4 years (mean, 7.4 months). Echocardiography was always performed before any invasive procedure. An adequate window for imaging the DA was obtained by parasternal, two-dimensional echocardiography in 209 patients (98%). A persistent ductus arteriosus (PDA) was detected by invasive methods in 79 of 209 patients (38%), and by two-dimensional and Doppler echocardiography in 76 (sensitivity, 96%; specificity, 100%). The echocardiographic and angiographic findings agreed closely as to the duct's morphology. Our technique permits an accurate visualization of the duct in neonates, infants, and small children with various forms of congenital heart disease.  相似文献   
62.
Simultaneous evaluation of acellular pertussis vaccines from three manufacturers (Takeda, Biken, and Chiba) was performed. After receiving two doses of acellular pertussis vaccine in the form of DPT (diphtheria pertussis tetanus), both infants and children showed high serum anti-PT (pertussis toxin) and anti-FHA (fdamentous hemagglutinin) antibody levels. These levels were equivalent to those observed in children in the convalescent stage of natural pertussis infection. Children who received 2 doses of Biken vaccine showed higher anti-PT and anti-FHA antibody levels than those who received Takeda or Chiba vaccine. Elevation of agglutinin titers was observed in children who received either Takeda or Chiba vaccine. ( Acta Paediatr Jpn 1989; 31: 120–126)  相似文献   
63.
Sodium d -glucaro-δ-lactam (ND2001) inhibited spontaneous pulmonary metastases of the highly metastatic B16 melanoma variant with a maximal inhibition rate of 99.5%, and 6 of 7 animals remained metastasis-free. Likewise, ND2001 inhibited the spontaneous pulmonary metastases of both Lewis lung carcinoma (3LL) with a rate of 98.0% (3 of 5 animals remaining metastasis-free) and rat KDH-8 liver carcinoma with a rate of 82.5% (3 of 7 animals remaining metastasis-free), although it was unable to inhibit the metastases of mouse BMT-11 fibrosarcoma and rat SST-2 breast carcinoma. Pretreatment with ND2001 in vitro inhibited the pulmonary metastases of the B16 variant and 3LL cells, which indicates direct action upon the cancer cells. When the invasive activity of cancer cells was measured by the Boyden chamber method, the number of invading B16 variant or 3LL cells was reduced with maximal inhibition rates of 93.0% or 89.9%, respectively, but pretreatment with ND2001 failed to reduce the invasive activity of BMT-11 or SST-2 cells. ND2001 showed neither cytocidal nor antitumor activity. These results suggest that ND2001 inhibited pulmonary metastases at the invasive step into the basement membrane by directly changing some property of the tumor cells.  相似文献   
64.
To clarify the mechanism of in vivo proliferation of adult T cell leukemia (ATL) cells, we examined the organ distribution of ATL-43T cell line cells derived from original leukemic cells in severe combined immunodeficiency (SCID) mice using radiometric techniques. First, we injected 111In-oxine-labeled ATL-43T cells into SCID and CB17 mice. On day 6, significant accumulation of radioactivity was found in the spleen and thymus of SCID mice (33.3±9.4 and 10.0±3.6 % injected dose/g of tissue [%ID/g], respectively) in comparison with that in CB17 mice (19.1±2.5 and 3.7±0.9 %ID/g, respectively). Next, we injected radiolabeled anti-Tac monoclonal antibody (MoAb) recognizing human interleukin-2 receptor (IL-2R) α chain or isotype-matched control MoAb RPC5 in SCID mice bearing ATL-43T cells 4 weeks after cell inoculation. The amounts of radioactivity found in the spleen and thymus of SCID mice injected with 125I-labeled anti-Tac MoAb (22.5±6.9 and 22.8±9.6 %ID/g, respectively) were significantly higher than those in the corresponding organs of SCID mice injected with 125I-labeled RPC5 MoAb (12.0±5.1 and 7.5±4.6 %ID/g, respectively). Similar results were obtained with 111In-labeled anti-Tac MoAb. These results were consistent with the histological findings of SCID mice bearing ATL-43T cells, indicating that ATL-43T cells infiltrated preferentially into the lymphoid organs, such as the spleen and thymus, and proliferated there. Thus, the radiometric techniques employed in this study were very useful to evaluate the proliferation sites of ATL-43T cells in SCID mice. Furthermore, this murine model could give us an opportunity to test the feasibility of therapeutic application of radiolabeled anti-Tac MoAb.  相似文献   
65.
1. The aim of the present study was to determine whether the vasorelaxant effect of atrial natriuretic peptide (ANP) is, in part, endothelium dependent in humans. 2. We used veno-occlusive plethysmography to measure forearm blood flow (FBF) during intra-arterial infusions of ANP (4, 8, 16, 32 pmol/min per dL forearm tissue volume) before and after the inhibition of nitric oxide (NO) synthesis by N(G)-monomethyl-L-arginine (L-NMMA; 100 micromol) in seven normal healthy subjects. 3. Atrial natriuretic peptide caused a dose-dependent increase in FBF both before and after L-NMMA and significantly reduced the plasma concentration of angiotensin (Ang) II. Administration of L-NMMA significantly diminished the increase in FBF in response to ANP infusion (P < 0.05). 4. These results suggest that the forearm vasodilative response to ANP is modulated, in part, by an endothelium-derived NO-mediated mechanism associated with a decrease in AngII caused by ANP.  相似文献   
66.
1. Acute exposure to ozone is known to cause airway hyperresponsiveness, which, at least in part, seems to result from an increase in the permeability of the airway mucosa. Recently, we demonstrated that depletion of sensory neuropeptides inhibits the ozone-induced increase in the permeability of the tracheal mucosa in guinea-pigs. The aim of this study was to determine whether tachykinins mediate ozone-induced increase in the permeability of the tracheal mucosa in guinea-pigs. 2. Anaesthetized guinea-pigs were exposed to either 3 p.p.m. ozone or filtered air for 30 min. Immediately after exposure, a tracheal segment was isolated in vivo and administered with horseradish peroxidase (HRP). The permeability was assessed by monitoring the appearance of HRP in the blood. 3. A low dose of NKA increased the permeability of the tracheal mucosa, whereas a low dose of SP was without effect. Low and high doses of the selective NK(3) receptor agonist, senktide, were also without effect. The effect of a low dose of NKA was abolished by the NK(2) receptor antagonist, SR-48,968. A high dose of SP increased the permeability in a manner reversible by the NK(1) receptor antagonist, CP-96,345. 4. Pretreatment with SR-48,968 completely inhibited the ozone-induced increase in the permeability, whereas CP-96,345 had no effect. 5. It is thus concluded that endogenous tachykinins mediate the ozone-induced increase in the permeability of the tracheal mucosa in guinea-pigs mainly via NK(2) receptor activation.  相似文献   
67.
68.
A significant difference in blood-acetaldehyde concentration was observed between high alcohol-preference (HAP) rats and low alcohol-preference (LAP) rats, newly developed different alcohol preference lines. This difference of acetaldehyde accumulation may be due to cytosolic aldehyde dehydrogenase (ALDH1) polymorphism, which has been reported previously. As the doses of ethanol we employed are higher than that of voluntary drinking, there may be little direct relationship between acetaldehyde accumulation and alcohol preference. We suggest therefore that the ALDH1 polymorphism is associated with alcohol preference in HAP/LAP lines through some other unidentified mechanism.  相似文献   
69.
OBJECTIVES: Children with autism spectrum disorder (ASD) frequently reveal various gastrointestinal (GI) symptoms that may resolve with an elimination diet along with apparent improvement of some of the behavioral symptoms. Evidence suggests that ASD may be accompanied by aberrant (inflammatory) innate immune responses. This may predispose ASD children to sensitization to common dietary proteins (DP), leading to GI inflammation and aggravation of some behavioral symptoms. METHODS: We measured IFN-gamma, IL-5, and TNF-alpha production against representative DPs [gliadin, cow's milk protein (CMP), and soy] by peripheral blood mononuclear cells (PBMCs) from ASD and control children [those with DP intolerance (DPI), ASD siblings, and healthy unrelated children]. We evaluated the results in association with proinflammatory and counter-regulatory cytokine production with endotoxin (LPS), a microbial product of intestinal flora and a surrogate stimulant for innate immune responses. RESULTS: ASD PBMCs produced elevated IFN-gamma and TNF-alpha, but not IL-5 with common DPs at high frequency as observed in DPI PBMCs. ASD PBMCs revealed increased proinflammatory cytokine responses with LPS at high frequency with positive correlation between proinflammatory cytokine production with LPS and IFN-gamma and TNF-alpha production against DPs. Such correlation was less evident in DPI PBMCs. CONCLUSION: Immune reactivity to DPs may be associated with apparent DPI and GI inflammation in ASD children that may be partly associated with aberrant innate immune response against endotoxin, a product of the gut bacteria.  相似文献   
70.
PURPOSE: We studied the effects of the age and/or disease duration in diabetics on the progression of diabetic retinopathy (DR). METHODS: The population consisted of 3614 type 2 diabetes mellitus (DM) patients. The subjects were divided into three age groups (elderly, > or = 65 years old; middle-aged, 64-40 years old, and younger < 40 years old) for disease duration-adjusted comparison with and without DR and proliferative diabetic retinopathy (PDR). Then, in 503 patients with 8-year follow-up data available, the frequency of development/progression of DR and the rate of progression to PDR were compared among the three groups. Thirdly, in the elderly patients, DR prevalence and the frequency of the development/progression of DR were compared between two groups with different diabetes duration (> or = 6 years and < or = 5 years). RESULTS: The prevalence of DR increased significantly with age (P < 0.001). The prevalence of PDR decreased significantly with age (P < 0.001). The overall frequency of the development and/or progression of DR increased significantly with age (P = 0.002); however, age was not related to the frequency of progression to PDR. In the patients with diabetes duration of 6-15 years, the frequency of the development/progression of DR and of progression to PDR after an 8-year follow up tended to decrease with age. Elderly patients with a diabetes duration of > or = 6 years showed significantly higher rate of prevalence of DR and frequency of development/progression of DR in an 8-year period than those with diabetes of a shorter duration (P < 0.001 and P < 0.001, respectively). CONCLUSION: In elderly DM patients, the prevalence of DR was increased even in the short duration and development/progression rates of DR were increased, while the relative frequency of PDR was decreased. Older-onset DM patients appear to be at a lower risk for progression to PDR.  相似文献   
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