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101.
C. Brandimarte C. Santini M. Venditti P. Baiocchi P. Serra P. Gallo G. d'Amati L. Rizzo F. Speziale P. Fiorani 《European journal of epidemiology》1989,5(4):521-525
To investigate the clinical significance of intraoperative cultures in elective abdominal aortic aneurysmectomy, we cultured the aneuryrymml wall and contents in 90 patients undergoing vascular graft surgery. Prosthetic graft infection was documented in 1 out of 62 patients with negative cultures and in none of 28 patients with positive cultures (x2 = 0.4, p > 0.1). Bacterial growth was seen in neither of 2 inflammatory aneurysms, 3 of 14 atherosclerotic aneurysms and 2 of 5 aneurysms without specific features. A retrospective analysis of patients' charts aimed at finding possible risk factors failed to identify any correlation between results of cultures and length of hospitalization before surgery, time interval between angiography and surgery, route of angiography procedure or minutes of surgery before sample collection. We conclude that positive cultures may not imply clinical infection at the time of surgery and that prolonged post-operative organism-specific antibiotic therapy does not appear necessary to prevent graft contamination in patients undergoing elective abdominal aortic aneurysmectomy. 相似文献
102.
Autoimmune hepatitis type 1 and primary biliary cirrhosis have distinct bone marrow cytokine production 总被引:3,自引:0,他引:3
Zachou K Rigopoulou EI Tsikrikoni A Alexandrakis MG Passam F Kyriakou DS Stathakis NE Dalekos GN 《Journal of autoimmunity》2005,25(4):389-288
We have recently reported differences in the hematopoiesis between autoimmune hepatitis type 1 (AIH-1) and primary biliary cirrhosis (PBC). In view of the notion that cytokines are regulators of hematopoiesis, we investigated in our tertiary center the cytokine production in the bone marrow (BM) of the same consecutive cohort of patients (13 AIH-1, 13 PBC, 10 healthy and 7 patients with cirrhosis due to chronic hepatitis B). Interferon-gamma (IFN-gamma), interleukin-4 (IL-4), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta) were determined in the supernatants of long-term BM cultures by ELISAs. IL-4, TNF-alpha and TGF-beta were found significantly increased in the BM of PBC patients compared to AIH-1 and both control groups. AIH-1 patients had significantly higher BM IL-10 compared to PBC patients and higher IL-10, IL-4 and TNF-alpha compared to controls. BM IFN-gamma was significantly higher in PBC and AIH-1 patients compared to controls. In AIH-1 patients, IL-10 was positively correlated with CD34+, CD34+/CD38- and CD34+/CD38+ cell proportions. In conclusion, the BM cytokine microenvironment of PBC and AIH-1 patients differs significantly compared to that of healthy individuals and cirrhotic patients of non-autoimmune etiology. Differences were also found between patients with PBC and AH-1. The implication of BM in the pathogenesis of autoimmune liver diseases is possible and needs further investigation. 相似文献
103.
Bound immunoglobulins of classes M,A, and G studied in the thymus of patients with myasthenia gravis
É. V. Gnezditskaya L. V. Beletskaya I. Kh. Ippolitov D. I. Shagal 《Bulletin of experimental biology and medicine》1978,85(6):776-779
Deposits of granular material containing immunoglobulins (Ig) of the M, A, and G classes, were found by direct immunofluorescence in the thymus of patients with myasthenia. Treatment of sections of the thymus of myasthenic patients with unlabeled preparations against individual classes of human Ig inhibits the reaction of the granular material with homologous labeled preparations. Disappearance of fluorescence of the deposits also was observed in sections treated with glycine-HCl buffer, pH 2.8. These results suggest that the granular material consists of immune complexes in which IgM, IgA, and IgG act as antibodies and components of the thymus tissues as the antigen. The presence of bound Ig in the thymus is evidence that in myasthenia an autoimmune process directed against the tissues of this organ is involved.Laboratory of Streptococcal Infections, N. F. Gamaleya Institute of Epidemiology and Microbiology. Professorial Surgical Department, I. M. Sechenov First Moscow Medical Institute. Laboratory of Clinical Pathophysiology, Institute of General and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR M. I. Kuzin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 6, pp. 709–712, June, 1978. 相似文献
104.
甲状腺疾病患者血清可溶性白细胞介素2受体测定的临床意义 总被引:2,自引:0,他引:2
某些甲状腺疾病时血清可溶性白细胞介素2受体(sIL-2R)水平及其与游离甲状腺素(FT_4)、游离三碘甲腺原氨酸(FT_3)和促甲状腺素(TSH)水平的相关性比较。结果发现甲状腺机能亢进症(甲亢)未治疗组(A)及甲亢未治疗伴突眼组(D)血清sIL-2R明显升高;甲状腺机能减退症(甲减)经治疗甲状腺功能灭常组(G)sIL-2R明显高于甲减未治疗组(F);10例毒性弥漫性甲状腺肿(Graves病)患者经抗甲状腺药物治疗后sIL-2R明显降低;Graves病及甲减患者血清sIL-2R均与FT_3呈正相关。提示除自身免疫外,甲状腺素水平也是甲状腺疾病患者血清sIL-2R水平的重要调节因素。 相似文献
105.
A new one-step computational procedure is presented for estimating the parameters of the nonlinear three-element windkessel
model of the arterial system incorporating a pressure-dependent compliance. The data required are pulsatile aortic pressure
and flow. The basic assumptions are a steadystate periodic regime and a purely elastic compliant element. By stating two conditions,
zero mean flow and zero mean power in the compliant element, peripheral and characteristic resistances are determined through
simple closed form formulas as functions of mean values of the square of aortic pressure, the square of aortic flow, and the
product of aortic pressure with aortic flow. The pressure across as well as the flow through the compliant element can be
then obtained so allowing the calculation of volume variation and compliance as functions of pressure. The feasibility of
this method is studied by applying it to both simulated and experimental data relative to different circulatory conditions
and comparing the results with those obtained by an iterative parameter optimization algorithm and with the actual values
when available. The conclusion is that the proposed method appears to be effective in identifying the three-element windkessel
even in the case of nonlinear compliance. 相似文献
106.
Eakin EG Sassi-Dambron DE Ries AL Kaplan RM 《International journal of behavioral medicine》1995,2(2):118-134
Dyspnea, the clinical term for shortness of breath, is the primary symptom and an important outcome measure in evaluations of patients
with lung disease. It is a subjective symptom that has proved difficult to quantify. Many dyspnea measures are available,
yet it is difficult, based on the existing literature, to determine the most reliable and valid. In this study, we evaluated
6 measures of dyspnea for reliability and validity: (a) Baseline Dyspnea Index (BDI) and Transition Dyspnea Index, (b) UCSD Shortness of
Breath Questionnaire (SOBQ), (c) American Thoracic Society Dyspnea Scale, (d) Oxygen Cost Diagram, (e) Visual Analog Scale,
and (f) Borg Scale. Subjects were 143 patients (74 women and 69 men) with obstructive lung disease, ages 40 to 86, FEV., 0.36
to 3.53 L, FVC 1.07 to 5.74 L. Dyspnea measures were assessed for test-retest reliability, internal consistency, interrater
reliability, and construct validity (i.e.. correlations among dyspnea measures and correlations of dyspnea measures with exercise
tolerance, health-related quality of life, lung function, anxiety, and depression). Results suggest that the SOBQ and BDI
demonstrated the highest levels of reliability and validity among the dyspnea measures examined.
This research was supported by University of California Tobacco Related Disease Research Program Grant 2RT026S, National Heart.
Lung, and Blood Institute Grant HL 34732 to Robert M. Kaplan, and National Institutes of Health NHLBI Preventive Pulmonary
Academic Award No. HL02215 to Andrew L. Ries. 相似文献
107.
对84例周围血管病(脉管炎68例,静脉炎16例)和25例正常健康人进行了足甲襞微循环的对比观察。结果:患病组足甲襞微循环的血管形态、流态、管周状态均较正常健康组有明显差异(P<0.01)。提示:更接近病变部位的局部微循环观察更能代表病变的程度,对临床医生判断病情、选择用药和疗效观察都有很大帮助和参考价值。 相似文献
108.
109.
Mechanical properties of dilated human ascending aorta 总被引:3,自引:0,他引:3
Okamoto RJ Wagenseil JE DeLong WR Peterson SJ Kouchoukos NT Sundt TM 《Annals of biomedical engineering》2002,30(5):624-635
Dilation of the ascending aorta, associated with Marfan Syndrome, bicuspid aortic valve, or advanced age, may lead to aortic dissection and rupture. Mathematical models can be used to assess the relative importance of increased wall stresses and decreased strength in these mechanical failures. To obtain needed inputs for such models, mechanical properties of dilated human ascending aorta were measured in vitro. Specimens for opening angle, biaxial elastic, and uniaxial circumferential strength tests were cut from excised tissue obtained from 54 patients (age 18–81 years) undergoing elective aortic graft replacement surgery. Opening angle was significantly greater in patients older than 50 years (262°±76°, n=21) compared to younger patients (202°±70°, n=13 All biaxial elastic specimens n=40 exhibited nonlinear stress-strain behavior. Rapid increases in circumferential and axial stresses occurred at lower strains in the older patient group than in the younger. Mean strength was significantly lower in older patients (1.35±0.37 MPa, n=14) than younger (2.04 ± 0.46 MPa, n=11, age <50 years). These changes in mechanical properties suggest that age may influence the risk of aortic dissection or rupture of dilated ascending aorta. © 2002 Biomedical Engineering Society.
PAC2002: 8719Rr, 8719Hh 相似文献
110.
H. Mine H. Kawai K. Yokoi M. Akaike S. Saito 《Journal of molecular medicine (Berlin, Germany)》1996,74(8):471-477
To investigate the relationship between human T-lymphotropic virus (HTLV) types I and II and the pathogenesis of autoimmune thyroid diseases, we examined serum anti-thyroid antibodies in 1019 blood donors with or without serum anti-HTLV-I antibody as well as proviral DNA for HTLV-II in leukocyte DNA by the polymerase chain reaction in 395 blood donors with or without anti-thyroid antibodies. The frequency of donors with anti-HTLV-I antibody who also showed anti-thyroid antibodies (7.9%) tended to be higher than that (6.3%) among donors who did not have the anti-HTLV-I antibody. The frequency of anti-thyroid antibodies in 125 young male donors aged 16–39 years with anti-HTLV-I antibody (4.8%) was significantly higher (P<0.05) than that (0.6%) in 164 control donors without the antibody. In blood donors with anti-thyroid antibody, 25.0% of those with anti-HTLV-I antibody and 14.3% of those without the antibody had HTLV-II proviral DNA. In contrast, in donors without anti-thyroid antibody HTLV-II proviral DNA was detected in 2.3% of those with anti-HTLV-I antibody and in 0.6% of those without the anti body. Thus the detection rates in donors with anti-thyroid antibody were significantly higher (P<0.001) than those in donors without the antibody, regardless of HTLV-I infection. These results suggest that HTLV-I infection and the presence of HTLV-II proviral DNA may be independently related to the pathogenesis of autoimmune thyroid diseases.Abbreviations
HTLV
Human T-lymphotropic virus
-
PCR
Polymerase chain reaction 相似文献