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141.
Lodewijk Cobben Ingrid Groot Lucas Kingma Emile Coerkamp Julien Puylaert Johan Blickman 《European radiology》2009,19(5):1175-1183
To establish the value of breathhold magnetic resonance imaging (MRI) in the diagnosis of acute appendicitis. Over a 14-month
period, 138 patients clinically suspected of having appendicitis were evaluated prospectively with MRI and comprised the study
group. Fast turbo spin-echo breathhold T1, T2 and T2 fat suppression sequences were used in coronal and axial planes. The
imaging results were recorded separately and subsequently correlated with clinical, radiological and histopathological follow-up.
The effect of imaging strategies in patients suspected of appendicitis on hospital resources was calculated. Sixty-two of
the 138 patients had a histopathologically proven appendicitis. MRI determined appendicitis in 63 patients, with one examination
being false positive. The resulting sensitivity and specificity were 100% and 99%, respectively. MRI showed an alternative
diagnosis in 41 of the 75 remaining patients. In 22 of the remaining 34 patients, a normal appendix was depicted with MRI.
In two patients, where MRI showed no appendicitis, an alternative diagnosis or normal appendix, an unnecessary appendectomy
was performed. The overall effect of using MRI in patients suspected of appendicitis on the use of hospital resources could
have been a net saving between € 55,746 and € 72,534. MRI has a high accuracy in detecting and excluding appendicitis, an
alternative diagnosis or showing the normal appendix, and can be a valuable and cost-effective tool in the workup of patients
clinically suspected of having appendicitis. 相似文献
142.
Structural degeneration of pulmonary homografts used as aortic valve substitute underlines early graft failure. 总被引:1,自引:0,他引:1
Dave R Koolbergen Mark G Hazekamp Emile de Heer Frans van Hoorn Hans A Huysmans Jan A Bruijn Robert A E Dion 《European journal of cardio-thoracic surgery》2002,22(5):802-807
OBJECTIVES: The limited availability of donor valves and experimental evidence that pulmonary valves can withstand systemic pressure made us use cryopreserved pulmonary homografts as aortic valve substitutes. We observed a high incidence of early reoperation because of severe graft insufficiency due to cuspal tears. The mid-term results are evaluated in this study and histological analysis of explanted homografts is performed to investigate the cause of graft failure. METHODS: From December 1991 to April 1994, 16 patients (13 male; mean age 37.3 years, range 21-59 years) underwent aortic valve replacement with a cryopreserved pulmonary homograft. The indication was endocarditis (n = 4), bioprosthesis degeneration (n = 3) or congenital aortic valve disease (n = 9). All homografts were implanted freehand in the subcoronary position. All patients were contacted for follow-up and recent echo-Doppler studies were reviewed. Six explanted homografts were examined microscopically using routine histological techniques to analyze changes in cell population, collagen and elastic fiber structure. RESULTS: Follow-up was complete in all patients. Reoperation was required in ten patients because of severe graft incompetence (mean implantation time 5.9 years, range 2.8-8.0 years). In two patients, recurrent endocarditis was the cause of graft failure. In the other eight patients the leaflets looked pliable and thin with gross tearing in one or more cusps. The histopathologic changes observed were remarkably similar in all examined grafts: the cusp tissue was almost non-cellular and the collagen fiber structure had mostly disappeared. At the site of rupture, the tissue had become thin with strongly degenerated collagen and elastic fiber structure. In the six patients with a homograft remaining in situ, echo-Doppler showed trivial to mild insufficiency in five cases and moderate to severe in one case, whereas no significant gradients were observed. CONCLUSIONS: We concluded that structural reduction of cell number and degenerative alterations in the molecular composition of the extracellular matrix in valve tissue is the main cause of early graft failure in this series. The use of cryopreserved pulmonary homografts in the systemic circulation is therefore not advised. 相似文献
143.
12 cases of polyneuropathy with IgM monoclonal gammapathy are reported. An analysis of the clinical, electrophysiological, histological and immunological features of these cases and of those reported in the literature allows to distinguish 2 groups. In the first group (8./12 cases), the neuropathy showed clinical and electrophysiological features of a mainly demyelinating mechanism involving large fibers. Electromicroscopy disclosed a widening of the spaces between the lamellae of the myelin in half of these cases. A monoclonal deposit of IgM was demonstrated by direct immunofluorescence, on the remaining myelinated fibers in most cases. In this first group, the M-component always reacted with the myelin sheaths of a monkey's peripheral nerve. The results of indirect immunofluorescence were closely correlated with those of immunoblotting, which revealed an anti-M.A.G. (Myelin Associated Glycoprotein) activity. The second group is more heterogeneous: there was an predominantly motor neuropathy (1 case), an asymmetrical and painful neuropathy with an endoneural deposit of IgM (1 case). In 2 other cases which in no other ways differed from those of the first group, the M-component seemed devoid of antimyelinic activity. Nevertheless, the presence of IgM on the myelin sheaths of these 2 cases suggested a relationship between the neuropathy and the gammapathy. In both groups, results from the association of apheresis and chlorambucil were difficult to assess and vary greatly. Therapy appeared beneficent in half of the cases, but only one patient was markedly improved. 相似文献
144.
R gis Maldiney Bernard Leroux Issam Sabbagh Bruno Sotta Lucienne Sossountzov Emile Miginiac 《Journal of immunological methods》1986,90(2):151-158
Avidin-biotin complexes have been used in an ELISA assay of three phytohormones: auxin (IAA), abscisic acid (ABA) and zeatin-riboside (ZR). Anti-hormone antibodies were elicited in rabbits immunized with hormone-bovine serum albumin conjugates. Microtitration plates coated with antigen protein were used in the ELISA method. The competition between plate-bound and free (standards or samples) antigen for a limiting amount of specific antibody results in a variable level of antibody adsorbed to the wells after washes. Such antibodies were labelled in two steps: first, incubation with biotinylated goat anti-rabbit IgG and, second, incubation with avidin-alkaline phosphatase conjugate. Bound ezyme activity was measured spectrophotometrically with p-nitrophenylphosphate and standard curves and ZR. The detection limit was 3–5 pg of plant hormone and the working range was between 10–1000 pg. This compares favourably with the best systems of analysis described in the literature. To avoid unwanted cross-reactions, a rapid and efficient HPLC purification step was included prior to measuring IAA, ABA and ZR in the same plant extract. About 100 mg fresh weight of a tomato sample could be analyzed by this technique. 相似文献
145.
Emile Cherbuliez Stefan Ansbacher 《Virchows Archiv : an international journal of pathology》1930,278(2):365-371
Ohne Zusammenfassung 相似文献
146.
147.
148.
STUDY OBJECTIVE: To examine transvaginal hydrolaparoscopy (THL) practices in French tertiary care centers. DESIGN: Prospective longitudinal study (Canadian Task Force classification III). SETTING: University hospital in France. PARTICIPANTS: Gynecology and obstetrics departments of all 48 French teaching hospitals. INTERVENTIONS: Practice of THL using a 8-item questionnaire. MEASUREMENTS AND MAIN RESULTS: Main outcome measure was practice, indications, and complications of THL in French tertiary care centers. Between October 2005 and March 2006, the departments were sent an 8-item questionnaire on the use of diagnostic and operative THL. In all, 38 (79%) hospitals completed the questionnaire. THL was or is still used in 20 (53%) departments. The main reason given by the 18 departments that never used THL was that it was "less informative than laparoscopy." Only 8 (40%) of 20 departments with experience of THL continued to use the procedure routinely. The main reason given for abandoning THL was its limited operative potential. Among the 8 departments that continued to use THL, 6 used operative THL (mainly for ovarian drilling). Among the 30 departments that answered the item on the likely future place of THL, only 6 (20%) considered that THL would continue to be performed. CONCLUSION: Few French teaching hospitals routinely use THL. Further data on THL, and especially its cost effectiveness, are needed to clarify its place to evaluate female fertility. 相似文献
149.
150.
C-reactive protein and features of the metabolic syndrome in a population-based sample of children and adolescents 总被引:6,自引:0,他引:6
Lambert M Delvin EE Paradis G O'Loughlin J Hanley JA Levy E 《Clinical chemistry》2004,50(10):1762-1768
BACKGROUND: C-Reactive protein (CRP) is a risk marker for type 2 diabetes and cardiovascular diseases. In youth, limited data are available on the distribution of high-sensitivity CRP as well as on its association with components of the metabolic syndrome. METHODS: In 1999, we conducted a school-based survey of a representative sample of youths 9, 13, and 16 years of age in the province of Quebec, Canada. Standardized clinical measurements and fasting plasma lipid, glucose, insulin, and CRP concentrations were available for 2224 individuals. RESULTS: The distribution of CRP was positively skewed. The median and 95th percentile values by age and sex ranged from < 0.2 to 0.56 mg/L and from 2.72 to 6.28 mg/L, respectively. A total of 7.7% of 9-year-olds, 5.5% of 13-year-olds, and 12.8% of 16-year-olds had CRP concentrations > 3.0 mg/L, the threshold defining the adult high-risk category. We observed a strong relationship between CRP concentrations and both body mass index (BMI) and fasting insulin values. The association between CRP and insulin concentration was markedly attenuated after adjustment for BMI, whereas that between CRP and BMI remained unchanged after adjustment for insulin: a 1 SD increase in BMI was associated with a 52% increase in CRP concentration. An increased CRP concentration was independently associated with a worsening of the lipid profile, whereas the association between increased CRP values and high systolic blood pressure was no longer statistically significant after adjustment for BMI. CONCLUSIONS: The metabolic correlates of excess weight, including a state of low-grade systemic inflammation, are detectable early in life. Their health impact in adults remains to be fully examined. 相似文献