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101.
Natali A Vichi S Landi P Toschi E Severi S L'abbate A Ferrannini E 《Journal of internal medicine》2000,247(2):219-230
OBJECTIVES: To evaluate how the presence of arterial hypertension affects coronary atherosclerosis and prognosis in patients with, or at high risk of, ischaemic heart disease. DESIGN: Retrospective analysis of clinical records and follow-up data. SETTINGS: Single referral centre for ischaemic heart disease. SUBJECTS: All consecutive patients (n = 1700, 38% with hypertension) undergoing coronary angiography for the evaluation of ischaemic heart disease during 1983-92. RESULTS: On angiography, the likelihood of having three-vessel disease was higher amongst hypertensives (odds ratio = 1.41; 95% confidence interval [CI] = 1.08-1.85) after adjustment for age, sex, and angina symptoms. The sum of all visible stenoses (an index of overall atherosclerotic involvement) was 19% higher in hypertensives (262 +/- 204 vs. 220 +/- 194 units, P < 0.005). By multivariate analysis, the presence of hypertension made a modest (+ 28 units), albeit statistically significant, independent contribution to the total atherosclerosis score. On follow-up (median = 96 months), cardiovascular mortality was slightly higher in the hypertensive patients than in the normotensive group (P < 0.05 in a Kaplan-Meier analysis), but a proportional hazard analysis adjusting for age and gender showed no significant independent contribution of hypertension. Hypertensive patients, however, remained at higher risk of non-fatal myocardial infarction following discharge (adjusted odds ratio = 1.21, 95% CI = 1.03-1.46; P < 0.05). CONCLUSIONS: In this referral population, hypertension is a risk factor for presence of three-vessel disease. Distribution, severity and extension of coronary stenosis are similar to those of normotensive patients, and prognosis is only marginally affected. 相似文献
102.
Brennan FM; Browne KA; Green PA; Jaspar JM; Maini RN; Feldmann M 《Rheumatology (Oxford, England)》1997,36(6):643-650
Matrix metalloproteinase (MMP)-1 and MMP-3 levels were measured in serum
samples from rheumatoid arthritis (RA) patients undergoing a double-blinded
placebo-controlled trial with the chimaeric anti-tumour necrosis factor
(TNF)-alpha antibody cA2. Both MMP-1 (P < 0.015), but to a larger extent
MMP-3 (P < 0.001) levels were elevated in all RA patients prior to the
commencement of the trial compared with normal control sera. Following cA2
therapy, MMP-1 and MMP-3 levels were assessed in the placebo, and 1 and 10
mg/kg cA2-treated groups at 7, 14, 21 and 28 days. In both the 1 and the 10
mg/kg cA2-treated groups, a significant decrease in serum MMP-3 levels at
all time points was observed, reducing maximally to 41% of pre-infusion
values at day 7. MMP-1 levels were also reduced, but less dramatically than
MMP-3, to 85% of pre-infusion values after 14 days in the 10 mg/kg cA2
treated group. In a separate non-placebo-controlled study, we also
evaluated the tissue inhibitor of metalloproteinase (TIMP)-1 levels in
plasma following cA2 infusion. Pre-infusion TIMP-1 levels were above the
normal control range, but were significantly reduced (P < 0.035) 14 days
after infusion to 72% of pre-infusion values. This study confirms previous
reports that MMP-3 levels are elevated and correlate with measures of
inflammation in RA, and furthermore demonstrate that serum MMP-3 and MMP-1
levels are downmodulated following anti-TNF-alpha antibody therapy. Whilst
serum MMP-3 levels correlated with C-reactive protein (CRP) both prior to
and following anti-TNF-alpha antibody therapy, it remains to be
demonstrated that serum MMP-3 and/or MMP-1 levels reflect the cartilage and
bone resorptive processes which are evident in this disease.
相似文献
103.
Panzuto F Severi C Cannizzaro R Falconi M Angeletti S Pasquali A Corleto VD Annibale B Buonadonna A Pederzoli P Delle Fave G 《Journal of endocrinological investigation》2004,27(1):6-11
BACKGROUND: Chromogranin A (CgA) is considered the most accurate marker in the diagnosis of gastro-entero-pancreatic (GEP) endocrine tumors. Pancreatic polypeptide (PP) has also been proposed to play this role, but then not used due to its low sensitivity. The aim of the present study was to determine whether the assessment of PP would improve the diagnostic reliability of CgA in patients with GEP tumors. PATIENTS AND METHODS: Both markers were assessed in 68 patients [28 functioning (F), 40 non functioning (NF)]. Twenty-seven patients disease-free (DF) after surgery, and 24 with non-endocrine tumors (non-ETs) were used as control groups. RESULTS: CgA sensitivity was: 96% in F, 75% in NF, 74% in pancreatic, and 91% in gastrointestinal (GI) tumors. Specificity was 89% vs DF, and 63% vs non-ETs. PP sensitivity was: 54% in F, 57% in NF, 63% in pancreatic, and 53% in GI tumors. Specificity was 81% vs DF, and 67% vs non-ETs. By combining the two markers a significant gain in sensitivity vs CgA alone was obtained: overall in GEP tumors (96% vs 84%, p = 0.04), in NF (95% vs 75%, p = 0.02), and in pancreatic (94% vs 74%, p = 0.04). More specifically, a 25% gain of sensitivity was obtained in the subgroup of NF pancreatic tumors (93% vs 68%, p = 0.04). CONCLUSION: The combined assessment of PP and CgA leads to a significant increase in sensitivity in the diagnosis of GEP tumors, particularly in pancreatic NF. 相似文献
104.
105.
Michele Pier Luca Guarino Rosa Sessa Annamaria Altomare Silvia Cocca Marisa Di Pietro Simone Carotti Giovanna Schiavoni Rossana Alloni Sara Emerenziani Sergio Morini Carola Severi Michele Cicala 《Digestive and liver disease》2013,45(12):1011-1016
Background
Impairment of gastrointestinal motility is frequently observed in patients with severe infection.Aim
To assess whether exposure of human colonic mucosa to pathogenic lipopolysaccharide affects smooth muscle contractility.Methods
Human colonic mucosa and submucosa were sealed between two chambers, with the luminal side facing upwards and covered with Krebs solution, with or without lipopolysaccharide from a pathogenic strain of Escherichia coli (O111:B4; 1000 ng/mL), and with the submucosal side facing downwards into Krebs. The solution on the submucosal side was collected following 30-min mucosal exposure to Krebs without (N-undernatant) or with lipopolysaccharide (lipopolysaccharide undernatant). Undernatants were tested for lipopolysaccharide and hydrogen peroxide levels and for their effects on smooth muscle cells in the presence of catalase, indomethacin or MG132.Results
Smooth muscle cells incubated with N-undernatant had a maximal contraction of 32 ± 5% that was reduced by 62.9 ± 12% when exposed to lipopolysaccharide undernatant. Inhibition of contraction was reversed by catalase, indomethacin and MG132. Lipopolysaccharide levels were higher in the lipopolysaccharide undernatant (2.7 ± 0.7 ng/mL) than in N-undernatant (0.45 ± 0.06 ng/mL) as well as hydrogen peroxide levels (133.75 ± 15.9 vs 82 ± 7.5 nM respectively).Conclusions
Acute exposure of colonic mucosa to pathogenic lipopolysaccharide impairs muscle cell contractility owing to both lipopolysaccharide mucosal translocation and production of free radicals. 相似文献106.
运用Ca2+指示剂Fura-2作为细胞内钙离子的荧光探针,利用AR—CM—MIC阳离子测定系统,检测了分离的神经细胞内游离钙及其变化,并观测了DGAVP和Org2766对蛋白质合成抑制剂茴香霉素(ANI)引起细胞内钙离子浓度([Ca2+]i)变化的影响。结果表明茴香霉素可使[Ca2+]i显著升高,且有量效关系;DGAVP本身并不引起[Ca2+]i发生显著变化,但适当剂量的DGAVP可显著对抗一定剂量范围内ANI升高[Ca2+]i的作用,提示DGAVP对抗ANI的蛋白质合成抑制效应可能是通过拮抗ANI升高[Ca2+]i这一途径实现的,另一神经肽Org2766则可能不是通过这一机制发生作用。从细胞内Ca2+的角度看,这两种肽的作用机理显然是不同的。 相似文献
107.
Robertson RT; Gallardo KA; Claytor KJ; Ha DH; Ku KH; Yu BP; Lauterborn JC; Wiley RG; Yu J; Gall CM; Leslie FM 《Cerebral cortex (New York, N.Y. : 1991)》1998,8(2):142-155
The role of basal forebrain-derived cholinergic afferents in the
development of neocortex was studied in postnatal rats. Newborn rat pups
received intraventricular injections of 192 IgG-saporin. Following survival
periods ranging from 2 days to 6 months, the brains were processed to
document the cholinergic lesion and to examine morphological consequences.
Immunocytochemistry for choline acetyltransferase (ChAT) and in situ
hybridization for ChAT mRNA demonstrate a loss of approximately 75% of the
cholinergic neurons in the medial septum and nucleus of the diagonal band
of Broca in the basal forebrain. In situ hybridization for glutamic acid
decarboxylase mRNA reveals no loss of basal forebrain GABAergic neurons.
Acetylcholinesterase histochemistry demonstrates a marked reduction of the
cholinergic axons in neocortex. Cholinergic axons are reduced throughout
the cortical layers; this reduction is more marked in medial than in
lateral cortical areas. The thickness of neocortex is reduced by
approximately 10%. Retrograde labeling of layer V cortico-collicular
pyramidal cells reveals a reduction in cell body size and also a reduction
in numbers of branches of apical dendrites. Spine densities on apical
dendrites are reduced by approximately 20-25% in 192 IgG- saporin-treated
cases; no change was detected in number of spines on basal dendrites. These
results indicate a developmental or maintenance role for cholinergic
afferents to cerebral cortical neurons.
相似文献
108.
Pietro Rubegni Paolo Sbano Marco Burroni Gabriele Cevenini Caterina Bocchi Filiberto Maria Severi Massimiliano Risulo Felice Petraglia Giordana Dell''Eva Michele Fimiani Lucio Andreassi 《Skin research and technology》2007,13(2):143-147
BACKGROUND: Very few studies have tried to clarify how pregnancy influences the morphology of pigmented skin lesions (PSL). Our purpose was to objectively determine, by digital dermoscopy analysis (DDA), any dermoscopic changes of acquired melanocitic nevi during pregnancy and after 1 year from delivery. METHODS: Thirty-five healthy pregnant women and 35 age-matched female controls were enrolled in the study. Nevi of pregnant women were analysed by DDA between 5 and 8 weeks of pregnancy, between 39 and 41 weeks of pregnancy and 12 months after delivery. Nevi of control women were analysed by DDA in a month of the year matching the period of recruitment of pregnant women and 21 months later. RESULTS: Multivariate analysis of variance (manova) for repeated measures revealed that dermoscopic variables SKIN-GREEN-AVERAGE, SKIN-BLUE-AVERAGE and CONTRAST changed during pregnancy but returned to non-significant values after a year from delivery. The variable ENTROPY showed significant differences between initial evaluation and 1 year after delivery. Finally, the variable VARIANCE OF BORDER GRADIENT showed a significant difference between the first and the last evaluations, in both pregnant and control subjects. CONCLUSIONS: The study showed that pregnancy leads to significant modifications in PSL, especially with regard to pigment network, globules and architectural order or disorder. 相似文献
109.
110.
Franco Locatelli Fulvio Porta Marco Zecca Paolo Pedrazzoli Rita Maccario Simona Giani Vito Vitale Myriam Martinetti Evelina Mazzolari Arnalda Lanfranchi Luigi Nespoli Andrea Bacigalupo Francesca Severi 《American journal of hematology》1993,42(3):328-333
Bone marrow transplantation (BMT) using HLA-partially matched family donors has produced disappointing results (25–30% of long-term survivors) in patients with severe aplastic anemia. We describe two children affected by severe aplastic anemia, not responsive to immunosuppressive therapy, who underwent allogeneic bone marrow transplantation using a HLA-partially matched family donor. Both cases presented 2 first class HLA-antigens (A and B) disparity between donor and recipient. The pretransplant conditioning regimen consisted of cyclophosphamide, thoracoabdominal irradiation, cytosine-arabinoside, and antilymphocyte globulin. As graft versus host disease (GVHD) prophylaxis, Cyclosporine-A was administered at usual dosages for 6 months. A full marrow engraftment was observed in both cases. Only grade I acute GVHD, promptly responsive to corticosteroid therapy, developed with no chronic GVHD. Five months after transplant, both children progressively developed hypertension, renal function impairment, thrombocytopenia, and severe normochromic anemia, with erythropoietin serum levels lower than expected for the haematocrit. After antihypertension treatment and supportive therapy, the clinical picture progressively improved, while treatment with recombinant human erythropoietin completely corrected the long-lasting anemia. The two children are alive and well 28 months after the transplant, with a Karnofsky score of 100% and a normal peripheral blood count. The authors suggest that, once immunosuppressive therapy has failed, BMT from donors other than HLA-identical sibling is a feasible approach in children affected by severe aplastic anemia, not having an HLA-identical donor. © 1993 Wiley-Liss, Inc. 相似文献