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11.
Jean-Marie Boeynaems Anne De Leener Barbara Dessars Hector Rodriguez Villa-Lobos Jean-Claude Aubry Frédéric Cotton Philippe Thiry 《Clinical chemistry and laboratory medicine》2004,42(1):67-71
Polyethylene terephthalate (PET) tubes have several advantages over glass tubes: they are unbreakable, lighter and more easily disposed of. Despite a steady increase in their use and an expansion of the range of available tubes, few studies validating their use have been published in the literature. This paper describes the various studies that have been performed to compare VENOJECT glass, VENOSAFE PET and VENOSAFE PET/heparin tubes for the assay of a panel of analytes in routine clinical chemistry, immunochemistry, hormone and tumor marker analysis and trace metal determination. These studies demonstrate that VENOSAFE PET tubes are a suitable alternative to glass tubes. 相似文献
12.
Laurence J Kirmayer Morton Weinfeld Giovani Burgos Guillaume Galbaud du Fort Jean-Claude Lasry Allan Young 《Revue canadienne de psychiatrie》2007,52(5):295-304
OBJECTIVE: Research in the United States tends to attribute low rates of use of mental health services by immigrants to economic barriers. The purpose of our study was to examine this issue in the context of Canada's universal health care system. METHODS: A survey of the catchment area of a comprehensive clinic in Montreal interviewed random samples of 924 Canadian-born individuals and 776 immigrants born in the Caribbean (n = 264), Vietnam (n = 234), or the Philippines (n = 278) to assess their health care use for somatic symptoms, psychological distress, and recent life events. RESULTS: Overall rates of use of medical services in the past year were similar in immigrant (78.5%) and nonimmigrant (76.5%) groups. Rates of use of health care services for psychological distress were significantly lower among immigrants (5.5% compared with 14.7%, P < 0.001). This difference was attributable both to a lower rate of use of specialty mental health services by immigrants (2.5% compared with 11.7%, P < 0.001) and to differential use of medical services for psychological distress (3.5% compared with 5.8%, P = 0.02). When level of psychological distress was controlled, Vietnamese and Filipino immigrants were one-third as likely as Canadian-born residents to make use of mental health services. The lower rate of use by immigrants could not be explained by differences in sociodemographics, somatic or psychological symptoms, length of stay in Canada, or use of alternative sources of help. CONCLUSION: Immigrant status is associated with lower rates of use of mental health services, even with universal health insurance. This lower rate of use likely reflects cultural and linguistic barriers to care. 相似文献
13.
The efficacy of hydroxyzine and buspirone, controlled by placebo, was investigated in a double-blind, parallel group, multicentre
study conducted in France and the UK. A total of 244 patients with generalised anxiety disorder in primary care was allocated
randomly to treatments with hydroxyzine (12.5 mg morning and mid-day, 25 mg evening), buspirone (5 mg morning and mid-day,
10 mg evening) or placebo (three capsules/day) for 4 weeks, preceded by a 1-week single-blind placebo run-in and followed
by 1-week single-blind placebo administration. Rating scales were applied on days -7,0,7,14,12,28 and 35. Seventy percent
of the patients were female; the average age was 41 ± 11 years, and the mean Hamilton Anxiety Score at day 0 was 26.5 ± 4.2.
Only 31 of the 244 patients dropped out, but equally in the three groups. Intention-to-treat LOCF analyses on the primary
variable showed a significant difference only between hydroxyzine and placebo with respect to improvement on the Hamilton
Anxiety Scale (10.75 versus 7.23 points, respectively). Secondary variables such as CGI and self-ratings (HAD scale) showed
both hydroxyzine and buspirone to be more efficacious than placebo. Thus, hydroxyzine is a useful treatment for GAD.
Received: 26 January 1998/Final version: 15 May 1998 相似文献
14.
Bioconversion of chitin to chitosan: purification and characterization of chitin deacetylase from Mucor rouxii. 总被引:6,自引:1,他引:5 下载免费PDF全文
D Kafetzopoulos A Martinou V Bouriotis 《Proceedings of the National Academy of Sciences of the United States of America》1993,90(7):2564-2568
Chitin deacetylase, the enzyme that catalyzes the hydrolysis of acetamido groups of N-acetylglucosamine in chitin, has been purified to homogeneity from mycelial extracts of the fungus Mucor rouxii and further characterized. The enzyme exhibits a low pI (approximately 3). Its apparent molecular mass was determined to be approximately 75 kDa by sodium dodecyl sulfate/polyacrylamide gel electrophoresis and approximately 80 kDa by size-exclusion chromatography, suggesting that the enzyme exists as a monomer. Carbohydrate analysis of purified chitin deacetylase revealed that the enzyme is a high-mannose glycoprotein and that its carbohydrate content is approximately 30% by weight. Chitin deacetylase is active on several chitinous substrates and chitin derivatives. The enzyme requires at least four N-acetylglucosamine residues (chitotetraose) for catalysis, and it is inhibited by carboxylic acids, particularly acetic acid. When glycol chitin (a water-soluble chitin derivative) was used as substrate, the optimum temperature for enzyme activity was determined to be approximately 50 degrees C and the optimum pH was approximately 4.5. 相似文献
15.
Cranial sutures and craniometric points detected on MRI 总被引:2,自引:0,他引:2
Cotton F Rozzi FR Vallee B Pachai C Hermier M Guihard-Costa AM Froment JC 《Surgical and radiologic anatomy : SRA》2005,27(1):64-70
The main goal of the study was to determine on MRI the cranial sutures, the craniometric points and craniometric measurements, and to correlate these results with classical anthropometric measurements. For this purpose, we reviewed 150 cerebral MRI examinations considered as normal (Caucasian population aged 2049 years). For each examination we individualized 11 craniometric landmarks (Glabella, Bregma, Lambda, Opisthocranion, Opisthion, Basion, Inion, Porion, Infra-orbital, Eurion) and three measurements. Measurements were also calculated independently on 498 dry crania (Microscribe 3-DX digitizer). To validate the MRI procedure, we measured four dry crania by MRI and with compass or digital caliper gauges. Cranial sutures always appeared without signal (black), whatever the MRI sequence used, and they are better visualized with a 5 mm slice thickness (compact bone overlapping). Slice dynamic analysis and multiplanar reformatting allowed the detection of all craniometric points, some of these being more difficult to detect than others (Porion, Infra-orbital). The measurements determined by these points were as follows: VertexBasion height=135.66±6.56 mm; EurionEurion width=141.17±5.19 mm; GlabellaOpisthocranion length=181.94±6.40 mm. On the midline T1-weighted sagittal image, all median craniometric landmarks can be individualized and the GlabellaOpisthocranion length, VertexBasion height and parenchyma indices can be calculated. Craniometric points and measurements between these points can be estimated with a standard cerebral MRI examination, with results that are similar to anthropometric data. 相似文献
16.
Etienne O Gasnier C Taddei C Voegel JC Aunis D Schaaf P Metz-Boutigue MH Bolcato-Bellemin AL Egles C 《Biomaterials》2005,26(33):6704-6712
The surface of medical devices is a common site of bacterial and fungal adhesion, first step to the constitution of a resistant biofilm leading frequently to chronic infections. In order to prevent such complications, several physical and chemical modifications of the device surface have been proposed. Here, we experiment a new type of topical antifungal coating using the layer-by-layer technique. The nanometric multilayer film obtained by this technique is functionalized by the insertion of a chromogranin A-derived antifungal peptide (CGA 47-66, chromofungin). We show that the embedded peptide keeps its antifungal activity by interacting with the fungal membrane and penetrating into the cell. In vitro studies demonstrate that such an antifungal coating is able to inhibit the growth of yeast Candida albicans by 65% and completely stop the proliferation of filamentous fungus Neurospora crassa. The cytotoxicity of such a coating was also assessed by growing human gingival fibroblasts at its surface. Finally, the antifungal coating of poly(methylmethacrylate), a widely used material for biomedical devices, is successfully tested in an in vivo oral candidiasis rat model. Taken together, these results assessed the functionalized multilayer films containing a new potent antifungal non-toxic peptide, as a novel and promising technique for local antifungal protection. 相似文献
17.
18.
Iñigo Mujika Jean-Claude Chatard Sabino Padilla Charles Yannick Guezennec André Geyssant 《European journal of applied physiology》1996,74(4):361-366
During a winter training season, the effects of 12 weeks of intense training and 4 weeks of tapering off (taper) on plasma hormone concentrations and competition performance were investigated in a group of highly trained swimmers (n = 8). Blood samples were collected and the swimmers performed their speciality in competition at weeks 10 (mid-season), 22 (pre-taper) and 26 (post-taper). No statistically significant changes were observed in the concentrations of total testosterone (TT), non-sex hormone binding globulin-boundtestosterone (NSBT), cortisol (C), luteinising hormone, thyroid stimulating hormone, triiodothyronine, thyroxine plasma catecholamines, creatine kinase and ammonia during training and taper. Mid-season NSBT: C ratio and the amount of training were statistically related (r = 0.82,P < 0.05). Competition performance slightly declined during intense training [0.52 (SD 2.51) %, NS] and improved during taper [2.32 (SD 1.69)%,P < 0.01]. Changes in performance during training and taper correlated with changes in ratios TT: C (r = 0.86,P < 0.01andr = 0.81,P < 0.05, respectively) and NSBT: C (r = 0.77,P < 0.05 andr = 0.76,P < 0.05, respectively). In summary, these results showed that the monitored plasma hormones and metabolic indices were unaltered by 12 weeks of intense training and 4 weeks of taper. The TT: C and NSBT: C ratios, however, appeared to be effective markers of the swimmers' performance capacities throughout the training season. 相似文献
19.
Isabelle Dutriez Isabelle Lagny-Pourmir Jacques Epelbaum Jean-Claude Beauvillain 《Journal of chemical neuroanatomy》1996,12(2):85-104
Galanin is a 29-amino acid peptide widely distributed in the mammalian central nervous system. Galanin receptors in the guinea pig brain were visualized using [125I]galanin by in vitro receptor quantitative autoradiography. Scatchard analysis of [125I]galanin binding to slide-mounted sections revealed saturable binding to a single class of high affinity receptors with a KD of approximately 1 nM. Specific [125I]galanin binding sites were detected in a large number of brain areas (concentration range: from non detectable to 99.32 fmol/mg of tissular proteins). The anatomical mapping revealed high densities essentially in the telencephalon (e.g. lateral septal nuclei, amygdala, hippocampal dentate gyrus) and the diencephalon (e.g. the anterodorsal and medial habenular thalamic nuclei, the paraventricular, dorsomedian and median mammillary hypothalamic nuclei, the posterior lobe of the pituitary). Addition of Mg2+ and GTP increased binding in some areas such as the zona incerta, the median eminence and the arcuate nucleus, and decreased it in other areas such as the amygdala, the hippocampus and the mammillary nuclei. This regional heterogeneity in the effect of Mg2+ and GTP can be interpreted as: (1) different rates of galanin receptor occupancy by endogenous peptide; (2) a differential coupling of GTP binding proteins to galanin receptors in the brain structures; and (3) a different nature of receptors. At any rate, this study provides evidence for a specific GTP-sensitive galanin receptor in guinea pig brain with an extensive distribution suggesting various physiological implications. Comparison with studies performed in several mammals shows that the overall distribution of galanin receptors is well preserved among species. These data suggest that galanin may posses similar functional properties in the different species tested so far. Nevertheless, very distinct differences were found in some areas like the cortex, the hippocampus and the pituitary. 相似文献
20.
Absence of Correlation Between Delayed-Type Hypersensitivity and Protection in Experimental Systemic Candidiasis in Immunized Mice 总被引:2,自引:7,他引:2 下载免费PDF全文
We found that in mice which had been immunized intraperitoneally with 2 × 108 heat-killed Candida albicans cells there was a striking temporal relationship between resistance to systemic challenge with 106 living C. albicans cells and a number of measurable cellular parameters of the host response. These included the emergence of delayed-type hypersensitivity and the development of granulocytosis. Since it had been shown in previous work that granulocytosis was associated with an increase in resistance when nonspecific immunostimulation was used, we performed experiments to induce delayed-type hypersensitivity without any measurable modification of the granulocyte population. Adoptive transfer of delayed-type hypersensitivity with spleen cells from immune and resistant donor mice did not produce any increase in resistance in normal recipients. When separate groups of mice were immunized intraperitoneally or subcutaneously with varying doses of heat-killed C. albicans, we found that doses of less than 108 cells did induce significant delayed-type hypersensitivity without any increase in granulocytosis. In such mice, as well as in animals pretreated with immunomodulators before immunization with heat-killed C. albicans, the presence of cell-mediated immunity, as measured by the delayed-type hypersensitivity test, was not associated with an increase in resistance against systemic candidiasis. On the contrary, the results suggested that cell-mediated immunity was associated with an increase in the susceptibility of these mice. The same effect on candidiasis susceptibility was observed when animals were immunized with heat-killed filamentous C. albicans. 相似文献