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排序方式: 共有835条查询结果,搜索用时 31 毫秒
1.
A two-part closed-end survey similar to a survey done in 1980 was given to 25 family physicians at an academic family medical center to assess physician knowledge about five insurance programs covering most of the patients seeking care in the center, and to assess physician attitudes about the capitated insurance plan with which the clinic was affiliated. Results did not differ significantly from those obtained in a similar survey four years earlier at the same center. Physicians correctly identified benefits offered by insurance programs only about one half of the time and many did not ascertain patient insurance coverage at all. Physicians considered the most important advantages of capitated health care to be the patient protection from fees for services obtained, the coverage for health care maintenance, and the potential for controlling health care costs. Physician-perceived disadvantages included difficulties controlling costs generated by other specialists, dealing with after-the-fact authorization requests, controlling access to services, and obtaining information about costs within the capitated system. 相似文献
2.
Mulkerrin EC; Clark BA; Epstein FH 《QJM : monthly journal of the Association of Physicians》1997,90(6):411-415
We studied blood pressure and natriuretic responses to acute salt loading,
and the effect of non-steroidal anti-inflammatory agents on these
responses, in five healthy normotensive women aged 65 to 71 years. Five
women aged 25 to 31 years acted as controls. Intravenous saline loading,
with and without prior ingestion of ibuprofen, was 15 ml/kg/h for 3 h.
Baseline blood pressures were higher in the elderly. Saline infusion
without ibuprofen raised systolic blood pressure (SBP) by about 25 mmHg in
the older group only. Ibuprofen increased baseline SBP in the elderly (129
+/- 6 vs. 116 +/- 5 mmHg, p < 0.05). Saline loading after ibuprofen
again raised blood pressure by about 25 mmHg in the elderly only. The
elderly group showed markedly increased sodium excretion during saline
loading, but this was reduced by ibuprofen. Ibuprofen had no effect on SBP
or sodium excretion in controls. Ageing appears to increase susceptibility
to salt retention and hypertension from non-steroidal anti-inflammatory
agents.
相似文献
3.
Acute thoracic aortic dissection has a high mortality if untreated, so the diagnosis must be rapidly made if mortality is to be lowered significantly. Multiple imaging techniques are often used. This retrospective study from 1988 to 1993 assesses the usefulness in diagnosis of chest X-rays, computed tomography (CT) scanning, aortography, magnetic resonance imaging (MRI), trans-thoracic (TTE) and trans-oesophageal (TOE) echocardiography. Forty-two patients with a final clinical diagnosis of dissection were studied. The diagnosis was confirmed in 16 (13 at surgery and three at autopsy). Three died with dissection given as the only cause for death. Chest X-ray abnormalities were seen in all 19 patients with surgery or death from dissection, with a widened mediastinum and/or dilated aorta being present in 17. In the group of 16 patients with surgery or autopsy proof, CT scans found dissections in 9 of 12 patients studied and correctly classified the type in only five. Aortography was performed in five, with accurate depiction of dissection and type in all. TTE found dissections in three of eight patients imaged by this method. MRI and TOE were performed each on two patients, with accurate depiction of dissection and type in each. Because of the relatively low sensitivity of CT scanning in defining aortic dissections Westmead Hospital is currently assessing the use of TOE as the prime imaging modality prior to surgical intervention. 相似文献
4.
Schneeweiss B Druml W Graninger W Grimm G Kleinberger G Lenz K Laggner A 《Clinical nutrition (Edinburgh, Scotland)》1989,8(2):89-93
Oxygen consumption was measured simultaneously by the reverse Fick-principle (V02FICK) and by indirect calorimetry ("Metabolic Measurement Cart Horizon") (V02MMC) in 31 critically ill patients; 24 men and 7 women. Seventeen patients were breathing spontaneously, 14 patients were on mechanical ventilation. The fractional inspiratory oxygen concentration (FI02) in ventilated patients ranged from 0.21 to 0.4 (mean 0.302). Total oxygen consumption as measured by indirect calorimetry was 286.7 +/- 59.7 ml/min (mean +/- SD), and measured by reverse Fick-principle 258.9 +/- 52.2 ml/min (mean +/- SD). The coefficient of correlation between the two methods was r = 0.873. The absolute difference of oxygen consumption between reverse Fick-method and indirect calorimetry was 11.3%. Regression analysis according to Theil revealed a similar regression between spontaneously breathing and mechanically ventilated patients for the studied FI02 values below 0.4. It is concluded that indirect calorimetry is a reliable method for measuring oxygen consumption in spontaneously breathing as well as mechanically ventilated critically ill patients. 相似文献
5.
Barak Gaster John N Unterborn Richard B Scott Ronald Schneeweiss 《Academic medicine》2007,82(10):934-938
With thousands of complementary and alternative medicine (CAM) treatments currently being used in the United States today, it is challenging to design a concise body of CAM content which will fit into already overly full curricula for health care students. The purpose of this article is to outline key principles which 15 National Center for Complementary and Alternative Medicine-funded education programs found useful when developing CAM course-work and selecting CAM content. Three key guiding principles are discussed: teach foundational CAM competencies to give students a framework for learning about CAM; choose specific content on the basis of evidence, demographics and condition (what conditions are most appropriate for CAM therapies?); and finally, provide students with skills for future learning, including where to find reliable information about CAM and how to search the scientific literature and assess the results of CAM research. Most of the programs developed evidence-based guides to help students find reliable CAM resources. The cumulative experiences of the 15 programs have been compiled, and an annotated table outlining the most highly recommended resources about CAM is presented. 相似文献
6.
Castillo S Reyes G Tejedor D Mozas P Suarez Y Lasuncion MA Cenarro A Civeira F Alonso R Mata P Pocovi M;Spanish Group of FH 《Human mutation》2002,20(6):477
Familial hypercholesterolemia is a genetic disorder caused by mutations in the LDL receptor gene. During a survey of mutations of LDL receptor gene in Spanish FH patients we found two mutations in the same allele: a missense N543H mutation in exon 11 and a 9bp inframe deletion (2393del9) located in exon 17. This double mutant allele was founded in 10 out of 458 unrelated patients: one homozygous FH [N543H+2393del9] + [N543H+2393del9], one compound heterozygote [N543H+2393del9] + [W-18X+E256K] and 8 heterozygotes. Flow cytometric analysis showed a defective LDL binding (20% of normal value) and internalization (23%) in lymphocytes from the homozygous patient; furthermore, studies of mitogen-stimulated lymphocytes demonstrated that the ability of LDL to support cell proliferation was impaired. Unexpectedly, not all carriers of the double mutant allele develop hypercholesterolemia and, furthermore, cholesterol-lowering treatment of the homozygous patient resulted in a 58% LDL cholesterol reduction. In conclusion, the phenotypic expression in the homozygous and heterozygous patients presented here, as well as the LDL-receptor residual activity, allowed the classification of this mutation as mild extending the group of mild mutations found at homozygosity. 相似文献
7.
Victor S Sierpina Ronald Schneeweiss Moshe A Frenkel Robert Bulik Jack Maypole 《Academic medicine》2007,82(10):946-950
Fifteen U.S. academic programs were the recipients of a National Center for Complementary and Alternative Medicine R25 Education Grant Program to introduce curricular changes in complementary and alternative medicine (CAM) in their institutions. The authors describe the lessons learned during the implementation of these CAM education initiatives. Principal investigators identified these lessons along with discovered barriers and strategies, both those traditionally related to medical and nursing education and those unique to CAM education. Many lessons, barriers, and strategies were common across multiple institutions. Most significant among the barriers were issues such as the resistance by faculty; the curriculum being perceived as too full; presenting CAM content in an evidence-based and even-handed way; providing useful, reliable resources; and developing teaching and assessment tools. Strategies included integration into existing curriculum; creating increased visibility of the curriculum; placing efforts into faculty development; cultivating and nurturing leadership at all levels in the organization, including among students, faculty, and administration; providing access to CAM-related databases through libraries; and fostering efforts to maintain sustainability of newly established CAM curricular elements through institutionalization and embedment into overall educational activities. These lessons, along with some detail on barriers and strategies, are reported and summarized here with the goal that they will be of practical use to other institutions embarking on new CAM education initiatives. 相似文献
8.
Distribution of mutations in the PEX gene in families with X-linked hypophosphataemic rickets (HYP) 总被引:8,自引:0,他引:8
Rowe PS; Oudet CL; Francis F; Sinding C; Pannetier S; Econs MJ; Strom TM; Meitinger T; Garabedian M; David A; Macher MA; Questiaux E; Popowska E; Pronicka E; Read AP; Mokrzycki A; Glorieux FH; Drezner MK; Hanauer A; Lehrach H; Goulding JN; O'Riordan JL 《Human molecular genetics》1997,6(4):539-549
Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with
homologies to endopeptidases, on the X-chromosome), are responsible for
X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family
of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has
raised important questions regarding PEX function at the molecular level.
The aim of this study was to analyse 99 HYP families for PEX gene
mutations, and to correlate predicted changes in the protein structure with
Zn2+ metallopeptidase gene function. Primers flanking 22 characterised
exons were used to amplify DNA by PCR, and SSCP was then used to screen for
mutations. Deletions, insertions, nonsense mutations, stop codons and
splice mutations occurred in 83% of families screened for in all 22 exons,
and 51% of a separate set of families screened in 17 PEX gene exons.
Missense mutations in four regions of the gene were informative regarding
function, with one mutation in the Zn2+-binding site predicted to alter
substrate enzyme interaction and catalysis. Computer analysis of the
remaining mutations predicted changes in secondary structure,
N-glycosylation, protein phosphorylation and catalytic site molecular
structure. The wide range of mutations that align with regions required for
protease activity in NEP suggests that PEX also functions as a protease,
and may act by processing factor(s) involved in bone mineral metabolism.
相似文献
9.
Diana Lüftner Andreas D. Hartkopf Michael P. Lux Friedrich Overkamp Hans Tesch Adriana Titzmann Patrik Pschke Markus Wallwiener Volkmar Müller Matthias W. Beckmann Erik Belleville Wolfgang Janni Tanja N. Fehm Hans-Christian Kolberg Johannes Ettl Diethelm Wallwiener Andreas Schneeweiss Sara Y. Brucker Peter A. Fasching 《Breast care (Basel, Switzerland)》2021,16(2):108
BackgroundThe therapeutic armamentarium for patients with metastatic breast cancer is becoming more and more specific. Recommendations from clinical trials are not available for all treatment situations and patient subgroups, and it is therefore important to collect real-world data.SummaryTo develop recommendations for up-to-date treatments and participation in clinical trials for patients with metastatic breast cancer, the Prospective Academic Translational Research PRAEGNANT Network was established to optimize the quality of oncological care in the advanced therapeutic setting. The main aim of PRAEGNANT is to systematically record medical care for patients with metastatic breast cancer in the real-life setting, including the outcome and side effects of different treatment strategies, to monitor quality-of-life changes during therapy, to identify patients eligible for participation in clinical studies, and to allow targeted therapies based on the molecular structures of breast carcinomas.Key MessagesThis article describes the PRAEGNANT network and sheds light on the question of whether the various end points from clinical trials can be transferred to the real-world treatment situation. 相似文献
10.
L M Baldwin R A Rosenblatt R Schneeweiss D M Lishner L G Hart 《The Journal of rural health》1999,15(2):240-251
Rural and urban areas have significant differences in the availability of medical technology, medical practice structures and patient populations. This study uses 1994 Medicare claims data to examine whether these differences are associated with variation in the content of practice between physicians practicing in rural and urban areas. This study compared the number of patients, outpatient visits, and inpatient visits per physician in the different specialties, diagnosis clusters, patient age and sex, and procedure frequency and type for board-certified rural and urban physicians in 12 ambulatory medical specialties. Overall, 14.4 percent of physicians in the 12 specialties practiced exclusively in rural Washington, with great variation by specialty. Rural physicians were older and less likely to be female than urban physicians. Rural physicians saw larger numbers of elderly patients and had higher volumes of outpatient visits than their urban counterparts. For all specialty groups except general surgeons and obstetrician-gynecologists, the diagnostic scope of practice was specialty-specific and similar for rural and urban physicians. Rural general surgeons had more visits for gastrointestinal disorders, while rural obstetrician-gynecologists had more visits out of their specialty domain (e.g., hypertension, diabetes) than their urban counterparts. The scope of procedures for rural and urban physicians in most specialties showed more similarities than differences. While the fund of knowledge and outpatient procedural training needed by most rural and urban practitioners to care for the elderly is similar, rural general surgeons and obstetrician-gynecologists need training outside their traditional specialty areas to optimally care for their patients. 相似文献