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61.
The health industry may be the prototype for changing gender roles among managers. Already women dominate mid‐level management positions. Meager data exist on senior health executives. In this exploratory study we examine the professional experiences of nationally prominent women leaders in Washington, D.C., who have recently been at the forefront of changing national health policy. Their career development, management styles, and influence in national health policy are discussed and analyzed. The leadership style of these women differs from the traditional male style, and they experienced role conflicts in their rise to power. The women in this study may be foreshadowing the roles of new leaders in the health industry in the 1990s. 相似文献
62.
63.
Neuronavigation by intraoperative three-dimensional ultrasound: initial experience during brain tumor resection 总被引:28,自引:0,他引:28
Unsgaard G Ommedal S Muller T Gronningsaeter A Nagelhus Hernes TA 《Neurosurgery》2002,50(4):804-12; discussion 812
OBJECTIVE: Three-dimensional (3-D) ultrasound is an intraoperative imaging modality used in neuronavigation as an alternative to magnetic resonance imaging (MRI). This article summarizes 4 years of clinical experience in the use of intraoperative 3-D ultrasound integrated into neuronavigation for guidance in brain tumor resection. METHODS: Patients were selected for inclusion in the study on the basis of the size and location of their lesion. Preoperative 3-D MRI data were registered and used for planning as in other conventional neuronavigation systems. Intraoperative 3-D ultrasound images were acquired three to six times, and tumor resection was guided on the basis of these updated 3-D images. RESULTS: Intraoperative 3-D ultrasound represents a good solution to the problem of brain shift in neuronavigation because it easily provides an updated, and hence more accurate, map of the patient's true anatomy in all phases of the operation. Ultrasound makes it possible to follow the progression of the operation, and it improves the radicality of tumor resection by detecting tumor tissue that would remain if the imaging technology had not been used (in 53% of the cases). Integration of 3-D ultrasound with navigation technology solves the orientation problem experienced previously with two-dimensional ultrasound in neurosurgery. The technology makes it possible to directly compare intraoperative ultrasound and MRI data regarding visualization of the lesion. Ultrasound image quality is useful for guiding surgical procedures. CONCLUSION: Intraoperative 3-D ultrasound seems to provide a time- and cost-effective way to update high-quality 3-D maps used in neuronavigation. 相似文献
64.
Glutamate receptor changes associated with transient anoxia/hypoglycaemia in hippocampal slice cultures 总被引:2,自引:0,他引:2
Transient anoxia/hypoglycaemia in organotypic hippocampal slice cultures, a model of transient brain ischaemia, ultimately results in delayed cell death. Although the mechanisms underlying this delayed death remain unknown, an increase in excitatory drive has been postulated. We report here that transient anoxia/hypoglycaemia in rat hippocampal slice cultures resulted in a 70-80% enhancement of evoked, alpha-amino-3-hydroxy-5-methyl-4-isoxazolpropionic acid (AMPA) receptor-mediated, excitatory responses lasting over 60 min. This effect was prevented by blockade of N-methyl-d-aspartate (NMDA) receptors, did not involve changes of paired-pulse facilitation ratio, but was associated with a 50% increase in amplitude, but not frequency, of spontaneous miniature excitatory postsynaptic currents (mEPSCs). Consistent with this, paired recordings revealed the appearance of AMPA receptor-mediated EPSCs at previously silent synapses and occlusion by prior induction of long-term potentiation (LTP). Transient anoxia/hypoglycaemia further resulted in a 63% potentiation of evoked NMDA receptor-dependent synaptic responses, accounting for the 20% increase in ratio of AMPA to NMDA responses. No change in rectification properties of AMPA receptor-mediated currents could be detected within the first hour following anoxia/hypoglycaemia-induced potentiation. Western blot analyses of slice cultures exposed to either control conditions or a short anoxia/hypoglycaemia revealed a marked, 50-70% increase of GluR1, GluR2/3 and NR1 subunits 1 h, but not 15 min, after the anoxic/hypoglycaemic episode. This increase was blocked by an inhibitor of protein synthesis. Together these results indicate that a transient anoxia/hypoglycaemia is associated with a marked enhancement of excitatory transmission sharing similarities with the mechanisms underlying LTP, and is correlated with an increased synthesis of excitatory receptor subunits. 相似文献
65.
S. Thomas E. Aldlyami S. Gupta M. R. Reed S. D. Muller P. F. Partington 《Archives of orthopaedic and trauma surgery》2011,131(4):455-458
Introduction
Any increase in perforations in surgical gloves is a concern. We conducted a prospective study to find a clinically acceptable brand of latex-free gloves suitable for orthopaedic surgery. 相似文献66.
Saleh AS Najjar SS Muller DC Shetty V Ferrucci L Gelber AC Ling SM 《Osteoarthritis and cartilage / OARS, Osteoarthritis Research Society》2007,15(3):357-361
OBJECTIVE: Osteoarthritis (OA) and vascular stiffening may share elements of common pathogenesis, but their potential relatedness has been the focus of little prior inquiry. We tested the hypothesis that these two aging-associated conditions are related to each other. METHOD: We analyzed cross-sectional data from 256 participants of the Baltimore Longitudinal Study of Aging (BLSA), a study of normative aging. All underwent measurement of arterial pulse wave velocity (PWV), an index of vascular stiffness, as well as hand radiographs that were graded for evidence of OA. Twenty total joints across three joint groups (distal interphalangeal [DIP], proximal interphalangeal [PIP], carpal-metacarpal [CMC]) were each assigned a Kellgren-Lawrence grade (K-L) of 0 (normal) through 4 (severe), with K-L grades >or=2 considered evidence of definite OA. Radiographic hand OA was defined as definite OA changes in at least two of the three anatomic hand sites (DIP, PIP, CMC). OA burden was represented by the total number of affected OA joints, and a cumulative K-L grade was aggregated across all hand joint groups. The relationship of PWV with these three measures of hand OA was assessed by linear regression. RESULTS: Upon univariate analysis, the presence of radiographic hand OA (beta=218.1, P<0.01), the total number of OA joints (beta=32.9, P<0.01), and the cumulative K-L grade across all joint groups (beta=12.2, P<0.01) were each associated with increased PWV. These associations, however, were no longer significant in age-adjusted models. CONCLUSION: Although significant individual relationships between PWV and several measures of hand OA were observed, these associations were largely attributable to the confounding effect of age. 相似文献
67.
Adenosine instead of supranormal potassium in cardioplegic solution improves cardioprotection. 总被引:1,自引:0,他引:1
?yvind Jakobsen Stig Muller Erling Aarsaether Tor Steensrud Dag G S?rlie 《European journal of cardio-thoracic surgery》2007,32(3):493-500
OBJECTIVE: To determine whether adenosine instead of supranormal potassium in cold crystalloid cardioplegia gives satisfactory cardiac arrest and improved cardioprotection. Cold crystalloid cardioplegia with adenosine, procaine and magnesium (A) was compared with standard cold crystalloid hyperkalemic cardioplegia (K). METHODS: Sixteen pigs were randomized to receive either cold K (n=8) or A (n=8), where hyperkalemia was substituted with 1.2 mM adenosine. The cold (6 degrees C) cardioplegia was given intermittently and antegradely, with an aortic cross-clamp time of 1 h. Hemodynamic data was continuously measured and pressure-volume conductance catheters were used to determine global left ventricular systolic and diastolic function. Coronary flow and O2 content differences allowed determination of left ventricular energetics. Blood samples, and left ventricular microdialysis were used to measure parameters of ischemia. Measurements were done at 1 and 2 h after cross-clamp release. RESULTS: Mean arterial pressure was reduced with 55 mmHg (standard deviation, SD: 19) in the K group versus 30 mmHg (SD: 14) in the A group 2 h after cross-clamp release (p=0.030). Left ventricular contractility expressed as slope of the preload recruitable stroke work index (Mw) was reduced to 53% (SD: 14) in the K group versus 78% (SD: 23) in the A group 2h after cross-clamp release (p=0.046). Reduction of maximum of first derivate of pressure with respect to time (dP/dtmax) was 804 mmHg/s (SD: 189) in the K group versus 538 mmHg/s (SD: 184) in the A group (p=0.033). The slope of the myocardial oxygen consumption-pressure volume area was at 2 h reperfusion increased from 1.37 (SD: 0.64) to 2.86 (SD: 1.27) in the K group, whereas no shift was detected in the A group (p=0.019). Cardiac troponin T measured in the coronary sinus 1 h after cross-clamp release was 1.25 microg/l (SD: 0.64) in the K group versus 0.73 microg/l (SD: 0.31) in the A group (p=0.046). CONCLUSION: Adenosine instead of supranormal potassium in cold crystalloid cardioplegia gives satisfactory cardiac arrest, improves post cardioplegic left ventricular systolic function and efficiency, and attenuates myocardial cell damage. 相似文献
68.
Philippe Morel Yannick D. Muller Sophie Borot Lionel Badet Christian Toso Domenico Bosco Thierry Berney 《Transplant international》2014,27(9):949-955
Islet grafts isolated from young donors allow superior functional outcomes but are often associated with poor islet isolation yields. The objective of this study was to comparatively analyze the outcomes of islet isolation between young and older donors. We retrospectively analyzed 564 pancreas isolations performed at our institution. Isolation outcomes were compared between donors aged ≤20 years (n = 42, YD) and >20 years (n = 522, OD). Isolation procedure was identical in both groups. Prepurification percentage of embedded islets was higher in YD (44.3 ± 22.7% vs. 24.9 ± 20.9%, P < 0.001). This led to a lower recovery rate in YD (48% vs. 76%, P = 0.002) and hence lower postpurification IEQ/g pancreas in YD (2 412 ± 1 789 IEQ/g vs. 3 194 ± 1 892 IEQ/g, P = 0.01). Final yield was 180 982 ± 128 073 IEQ in YD and 244 167 ± 134 137 IEQ in OD, (P = 0.006). In vitro function was markedly, albeit nonsignificantly, higher in YD (SI: 4.5 ± 5.1 vs. 3.0 ± 5.7, P = 0.350). Proportion of transplanted preparations was similar in both groups, 38% (16/42) in YD vs. 43% (224/522) in OD, P = 0.628. In spite of isolation and purification difficulties, pancreases from young donors allowed similar islet transplantation rates as older donors. Efforts should be directed at improving islet extraction in these donors to realize their full potential for islet transplantation. 相似文献
69.
Carlos de Paula Eduardo Ana Cecilia Corrêa Aranha Alyne Simões Marina Stella Bello-Silva Karen Muller Ramalho Marcella Esteves-Oliveira Patrícia Moreira de Freitas Juliana Marotti Jan Tunér 《Lasers in medical science》2014,29(4):1517-1529
Recurrent herpes labialis is a worldwide life-long oral health problem that remains unsolved. It affects approximately one third of the world population and causes frequent pain and discomfort episodes, as well as social restriction due to its compromise of esthetic features. In addition, the available antiviral drugs have not been successful in completely eliminating the virus and its recurrence. Currently, different kinds of laser treatment and different protocols have been proposed for the management of recurrent herpes labialis. Therefore, the aim of the present article was to review the literature regarding the effects of laser irradiation on recurrent herpes labialis and to identify the indications and most successful clinical protocols. The literature was searched with the aim of identifying the effects on healing time, pain relief, duration of viral shedding, viral inactivation, and interval of recurrence. According to the literature, none of the laser treatment modalities is able to completely eliminate the virus and its recurrence. However, laser phototherapy appears to strongly decrease pain and the interval of recurrences without causing any side effects. Photodynamic therapy can be helpful in reducing viral titer in the vesicle phase, and high-power lasers may be useful to drain vesicles. The main advantages of the laser treatment appear to be the absence of side effects and drug interactions, which are especially helpful for older and immunocompromised patients. Although these results indicate a potential beneficial use for lasers in the management of recurrent herpes labialis, they are based on limited published clinical trials and case reports. The literature still lacks double-blind controlled clinical trials verifying these effects and such trials should be the focus of future research. 相似文献
70.
Ragnhild B. Wijma Marloes Emous Merel van den Broek Anke Laskewitz Anneke C. Muller Kobold André P. van Beek 《Surgery for obesity and related diseases》2019,15(1):73-81