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71.
Relationship of polymorphisms in the renin-angiotensin system and in E-selectin of patients with early severe coronary heart disease 总被引:8,自引:0,他引:8
K. Wenzel A. Blackburn M. Ernst M. Affeldt R. Hanke G. Baumann S. B. Felix F. X. Kleber K. Rohde C. Gläser A. Speer 《Journal of molecular medicine (Berlin, Germany)》1997,75(1):57-61
Previous association studies between angiotensin-converting enzyme (ACE) and angiotensinogen (AGT) polymorphisms and several
cardiovascular diseases have reported variable results. Therefore we examined the association of the DNA variants of ACE and
AGT with early, severe coronary heart disease (CHD). In addition, we compared the genotypes of both polymorphisms and the
recently discovered polymorphism in the E-selectin gene in both patients and an unselected population. This study included
113 patients with severe CHD (50 years old or less) and up to 197 control subjects. The frequencies of the ACE I/D variants
were 48% I and 52% D in the controls and 46% I and 54% D in the patients. The frequencies of the AGT-M235T polymorphism were
60.8% M and 39.2% T in controls and 49.1% M and 50.9% T in the patients. The frequencies of the S128R polymorphism of the
E-selectin were 91.3% S and 8.7% R in controls and 84.5% S and 15.5% R in the patients. In our studies the DD genotype of
ACE was not associated with early severe CHD. We found a correlation between the M235T molecular variant of AGT and the S128R
variant of E-selectin to early severe CHD.
Received: 15 February 1996 / Accepted: 2 October 1996 相似文献
72.
C Vissinga L Nagelkerken J Zijlstra A Hertogh-Huijbregts W Boersma J Rozing 《Mechanisms of ageing and development》1990,53(2):127-139
The data presented in this paper show that the in vivo delayed-type-hypersensitivity (DTH) reaction to both H-2 and non-H-2 alloantigens declines with increasing age. It is also shown that cells generated in vitro are capable to transfer DTH to young naive syngeneic recipients. Using this in vitro system it could be demonstrated that cells from old CBA/Rij mice induced lower DTH responses than cells from young CBA/Rij mice. Depletion experiments with the effector T cell population showed that the DTH effector phase is mediated by CD4+ T cells. Lower responses in old mice were not due to increased CD8+ suppressor T cell activity, since after removal of the CD8+ T cells old CD4+ cells were still less effective in the generation of DTH effector T cells than young CD4+ cells. Addition of IL-2 containing supernatant to in vitro cultures did not improve the subsequent DTH response. From these data it can be concluded that the reduced DTH responses in old mice are not solely due to CD8+ suppressor cell activity and/or lack of IL-2, but that rather intrinsic defects of the CD4+ T cell population appear to play a major role in the impaired DTH reactivity during ageing. 相似文献
73.
74.
Recent experiments have shown that shortening and stretching of sarcomeres in single activated and unactivated myofibrils occur in stepwise fashion (Yang et al. (1998) Biophys J 74: 1473-1483; Blyakhman et al. (2001) Biophys J 81: 1093-1100; Yakovenko et al. (2002) Am J Physiol Cell Physiol 283: 735-742). Here, we carried out measurements on single myofibrils from rabbit psoas muscle to investigate steps in unactivated specimens in more detail. Activated and unactivated myofibrils were released and stretched in ramp-like fashion. The time course of length change in the single sarcomere was consistently stepwise. We found that in the unactivated myofibrils, step size depended on initial sarcomere length, diminishing progressively with increase of initial sarcomere length, whereas in the case of activated sarcomeres, step size was consistently 2.7 nm. 相似文献
75.
Hyperspectral and multispectral bioluminescence optical tomography for small animal imaging 总被引:4,自引:0,他引:4
Chaudhari AJ Darvas F Bading JR Moats RA Conti PS Smith DJ Cherry SR Leahy RM 《Physics in medicine and biology》2005,50(23):5421-5441
For bioluminescence imaging studies in small animals, it is important to be able to accurately localize the three-dimensional (3D) distribution of the underlying bioluminescent source. The spectrum of light produced by the source that escapes the subject varies with the depth of the emission source because of the wavelength-dependence of the optical properties of tissue. Consequently, multispectral or hyperspectral data acquisition should help in the 3D localization of deep sources. In this paper, we describe a framework for fully 3D bioluminescence tomographic image acquisition and reconstruction that exploits spectral information. We describe regularized tomographic reconstruction techniques that use semi-infinite slab or FEM-based diffusion approximations of photon transport through turbid media. Singular value decomposition analysis was used for data dimensionality reduction and to illustrate the advantage of using hyperspectral rather than achromatic data. Simulation studies in an atlas-mouse geometry indicated that sub-millimeter resolution may be attainable given accurate knowledge of the optical properties of the animal. A fixed arrangement of mirrors and a single CCD camera were used for simultaneous acquisition of multispectral imaging data over most of the surface of the animal. Phantom studies conducted using this system demonstrated our ability to accurately localize deep point-like sources and show that a resolution of 1.5 to 2.2 mm for depths up to 6 mm can be achieved. We also include an in vivo study of a mouse with a brain tumour expressing firefly luciferase. Co-registration of the reconstructed 3D bioluminescent image with magnetic resonance images indicated good anatomical localization of the tumour. 相似文献
76.
Usefulness of immunohistochemistry in delineating renal spindle cell tumours. A retrospective study of 31 cases 总被引:3,自引:0,他引:3
Wang J Weiss LM Hu B Chu P Zuppan C Felix D Rausei-Mills V Chase DR 《Histopathology》2004,44(5):462-471
AIMS: To assess the usefulness of immunohistochemistry in delineating tumour diagnoses on a series of morphologically diagnosed renal spindle cell tumours (RSCTs). METHODS AND RESULTS: Formalin-fixed paraffin-embedded tissues from 31 morphologically diagnosed tumours were reinterpreted in light of newly obtained immunohistochemical information. By morphology, six had originally been classified as sarcomatoid carcinoma, five as spindle cell tumour (NOS), four as sarcoma (NOS), three as leiomyoma, three as leiomyosarcoma, and one each as fibrous polyp, hamartoma, neurilemmoma, mesoblastic nephroma, medullary fibroma, angiomyolipoma, haemangiopericytoma, malignant rhabdoid tumour, malignant Triton tumour, and carcinosarcoma. The application of immunohistochemistry verified the original diagnosis in 18 cases (18/31, 58%), confirming the diagnosis of sarcomatoid renal carcinoma (4/6), leiomyoma (2/3), leiomyosarcoma (3/3), sarcoma (NOS) (2/4), carcinosarcoma (1/1), malignant rhabdoid tumour (1/1), malignant Triton tumour (1/1), fibrous polyp (1/1), mesoblastic nephroma (1/1), hamartoma (1/1), and angiomyolipoma (1/1). Different tumour designations were suggested in 13 cases (13/31, 42%), including carcinosarcoma, sarcoma (NOS), leiomyosarcoma, solitary fibrous tumour, monomorphic/biphasic angiomyolipoma, endometrial stromal tumour, and congenital mesoblastic nephroma. CONCLUSIONS: Our data indicate that although morphology is most important in formulating the initial differential diagnosis, the addition of immunohistochemistry is vital in arriving at the correct classification of RSCTs. 相似文献
77.
J. Zweens Henny Frankena A. Reicher W. G. Zijlstra 《Pflügers Archiv : European journal of physiology》1980,385(1):71-77
The determination of D2O in biological fluids by means of infrared spectrometry was reinvestigated. When the temperature of a solution, containing D2O in the range from natural abundance to 5 ml·1–1 increases, its absorbance decreases and the wavenumber of maximum absorption shifts to a higher value. Both changes are linearly related to the change in temperature. Storage for 17 d in either glass or polyethylene tubes does not affect the D2O concentration. Purification of biological fluids by vacuum-sublimation removes all substances which also absorb at the O-D vibration band and the recovery of D2O from plasma and urine is complete. The partition ratio of D2O between plasma water and red cell water equals unity, and the same holds for plasma water and urine water over a wide range of urine flows and osmolalities. The arterial and urinary disappearance curves of D2O, measured over several days, both permit the calculation of the total amount of body water (V
bw), the daily water turn-over (F) and the half-time of water in the body (t
1/2), but the data derived from arterial disappearance curves are more precise. In 16 male mongrel dogs (25–32 kg body mass) the following results were obtained:V
bw=626±28 ml·kg–1,F=12.0±3.2% andt
1/2=6.21±1.78 d. 相似文献
78.
Ren A Tio Jasper S Wijpkema Eng S Tan Folkert W Asselbergs Geke A P Hospers Gillian A J Jessurun Felix Zijlstra 《Endothelium》2005,12(3):103-106
Vascular endothelial growth factor (VEGF) is a potent angiogenic factor. VEGF gene therapy improves perfusion of ischemic myocardium in experimental models and possibly in patients with end-stage coronary artery disease. In addition to its proliferative and migratory effect on endothelial cells, it also activates and up-regulates endothelial nitric oxide synthase (eNOS). Therefore, the authors investigated coronary endothelium-dependent vasodilatation in patients before and after VEGF gene therapy. The effect of intracoronary acetylcholine infusion on coronary diameter was assessed at baseline and after 3 months follow-up in patients with end-stage coronary artery disease treated with VEGF gene and in controls scheduled for elective percutaneous transluminal coronary angioplasty (PTCA) (acetylcholine test at diagnostic angiography and before a subsequently scheduled PTCA). Five out of six VEGF patients experienced a reduction in anginal complaints. Angiographic evidence for improved collateral filling was evident in two out of six patients. The vasoconstrictive response to acetylcholine was partly converted into dilatation. In contrast, the acetylcholine response in control patients remained vasoconstrictive. In conclusion, VEGF gene therapy has an important beneficial effect on the functional characteristics of the myocardial vascular network. Therefore, this therapy can potentially play an important role in all stages of the atherosclerotic process. 相似文献
79.
Y. L. Hoogeveen J. P. Zock P. Rispens W. G. Zijlstra 《Pflügers Archiv : European journal of physiology》1987,410(3):257-262
While maintaining the arterial CO2 tension constant near the normal level of the dog (4.3 kPa), we studied the influence of decreasing cardiac output on both the arterial and mixed-venous blood acid-base status in anaesthetized, artificially ventilated dogs. Cardiac output was manipulated by applying positive end-expiratory pressure (PEEP), and by -adrenergic blockade to suppress a compensatory heart rate response. The systemic vascular response was attenuated by -adrenergic blockade. Metabolic rate remained virtually unchanged when cardiac output decreased. Under these conditions a fall in cardiac output led to a shift of the arterial acid-base status in the direction of a metabolic acidosis. The changes occurring in the mixed-venous blood resembled those of an in-vivo CO2 bufferline, with the shift being such as if a respiratory acidosis was developing. 相似文献
80.
Timo D Müller Anke Hinney André Scherag Thuy T Nguyen Felix Schreiner Helmut Schäfer Johannes Hebebrand Christian L Roth Thomas Reinehr 《BMC medical genetics》2008,9(1):85