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11.
Our inability to associate distant regulatory elements with the genes they regulate has largely precluded their examination for sequence alterations contributing to human disease. One major obstacle is the large genomic space surrounding targeted genes in which such elements could potentially reside. In order to delineate gene regulatory boundaries, we used whole-genome human-mouse-chicken (HMC) and human-mouse-frog (HMF) multiple alignments to compile conserved blocks of synteny (CBSs), under the hypothesis that these blocks have been kept intact throughout evolution at least in part by the requirement of regulatory elements to stay linked to the genes they regulate. A total of 2116 and 1942 CBSs >200 kb were assembled for HMC and HMF, respectively, encompassing 1.53 and 0.86 Gb of human sequence. To support the existence of complex long-range regulatory domains within these CBSs, we analyzed the prevalence and distribution of chromosomal aberrations leading to position effects (disruption of a gene's regulatory environment), observing a clear bias not only for mapping onto CBS but also for longer CBS size. Our results provide an extensive data set characterizing the regulatory domains of genes and the conserved regulatory elements within them. 相似文献
12.
Effects of novel manufacturing technology on blood and dialysate flow distribution in a new low flux "alpha Polysulfone" hemodialyzer 总被引:1,自引:0,他引:1
Gastaldon F Brendolan A Crepaldi C Frisone P Zamboni S d'Intini V Poulin S Hector R Granziero A Martins K Gellert R Inguaggiato P Ronco C 《The International journal of artificial organs》2003,26(2):105-112
The main target for low flux hemodialyzers is an efficient low molecular weight solutes clearance. Such efficiency is largely dependent on the optimization of diffusion between blood and dialysis solution. The diffusion process can be impaired if there is a mismatch between blood and dialysate flow distribution in the dialyzer. Thus optimized flow distribution both in the blood and dialysate compartment becomes quintessential for the maximal efficiency of the diffusion process within the hemodialyzer. The present paper describes the distribution of the blood and dialysate flows in a new low flux polysulfone hollow fiber hemodialyzer characterized by a specific undulation of the fibers and a new cutting technology of the fibers for an improved micro-flow condition in the blood compartment headers. Twelve Diacap alpha Polysulfone LO PS 15 (1.5 sqm) (B.Braun Medizintechnologie, Melsungen Germany) were employed for the study. Six were analyzed in vitro and six were studied in vivo. Blood flow distribution was studied in vitro by dye injection in the blood compartment during experimental extracorporeal circulation utilizing human blood with hematocrit adjusted at 33%. Sequential images were obtained with a helical scanner in a fixed longitudinal section of the dialyzer 1 cm thick. Average and regional blood flow velocities were measured utilizing the reconstructed imaging sequence. The method allowed the calculation of single fiber blood flow (SF Qb) and the mass transfer zone (MTR) definition in digitally subtracted images. The patterns 20-10 and 40-30 were utilized. The same technology was used to evaluate flow distribution in the dialysate compartment after dye injection in the Hansen's connector. Regional dialysate flow was calculated in central and peripheral sample areas of 1 cm2. Six in vivo hemodialysis treatments on patients with end stage renal disease were performed at three different blood flow rates (250-350 and 450 ml/min) in order to measure urea, creatinine and phosphate clearance. Macroscopic and densitometrical analysis revealed that flow distribution was homogeneous in the blood compartment while in the dialysate compartment a slight difference between the peripheral and central regions in terms of flow velocity was observed. This however was not generating channeling phenomena. Urea creatinine and phosphate clearances were remarkably high and so were the Kt/V observed in all sessions, especially in relation to the studied blood flows. In conclusion, a significant blood to dialysate flow match with optimized countercurrent flow condition was observed in the studied hollow fiber hemodialyzers. Such optimization might be due both to the improved dialyzer design at the level of the blood header and to the specific fiber undulation that prevents dialysate channeling. 相似文献
13.
M Marty P Pouillart S Scholl J P Droz M Azab N Brion E Pujade-Lauraine B Paule D Paes J Bons 《The New England journal of medicine》1990,322(12):816-821
To compare ondansetron (GR 38032F), a 5-hydroxytryptamine3-receptor antagonist, with metoclopramide in the prophylaxis of acute cisplatin-induced emesis, we conducted a double-blind crossover study in 97 patients scheduled to receive cisplatin (80 to 100 mg per square meter of body-surface area) for treatment of cancer. None had received chemotherapy before this trial. Among the 76 patients who satisfactorily completed both parts of the study, complete or nearly complete control of emesis (i.e., no episodes of emesis occurred, or only one or two) was achieved in 57 of 76 treatments (75 percent) with ondansetron and in 32 of 76 treatments (42 percent) with metoclopramide (P less than 0.001). Ondansetron was also more effective in controlling acute nausea, as assessed with a visual-analogue scale (P = 0.019) or a graded scale (P = 0.024). There was a significant preference among patients for ondansetron (55 vs. 26 percent; P = 0.006). Dystonic reactions were observed during three treatments with metoclopramide; both agents were otherwise well tolerated. We conclude that ondansetron is more effective than metoclopramide in the control of cisplatin-induced nausea and vomiting, and that this suggests that serotonin is an important mediator of this side effect. 相似文献
14.
J C Monboisse G Poulin P Braquet A Randoux C Ferradini J P Borel 《International journal of tissue reactions》1984,6(5):385-390
Fibrils of collagen reconstituted in vitro by dialysis against sodium formate are exposed to free oxy radicals generated by three different systems: (i) xanthine oxidase + hypoxanthine, (ii) gamma-rays originating from a cobalt bomb; (iii) pulse radiolysis in a particle accelerator. A degradation of the collagen fibres is demonstrated by determination of the amount of hydroxyproline-containing peptides in the supernatant after incubation. Types I and III collagen are sensitive to the effect, whereas type V collagen is not. The effect persists when collagen is specially delipidated. 相似文献
15.
16.
Farace F Prestoz L Badaoui S Guillier M Haond C Opolon P Thomas JL Zalc B Vainchenker W Turhan AG 《Stem cells and development》2004,13(1):83-92
Muscle tissue of adult mice has been shown to contain stem cells with hematopoietic repopulation ability in vivo. To determine the functional characteristics of stem cells giving rise to this hematopoietic activity, we have performed hematopoietic reconstitution experiments by the use of muscle versus marrow transplantation in lethally irradiated mice and followed the fate of transplanted cells by Y-chimerism using PCR and fluorescence in situ hybridization (FISH) analysis. We report here that transplantation of murine muscle generate a major hematopoietic chimerism at the level of CFU-C, CFU-S, and terminally-differentiated cells in three generations of lethally irradiated mice followed up to 1 year after transplantation. This potential is totally abolished when muscle grafts were performed by the use of muscle from previously irradiated mice. As compared to marrow transplantation, muscle transplants were able to generate similar potencies to give rise to myeloid, T, B, and natural killer (NK) cells. Interestingly, marrow stem cells that have been generated in primary and then in secondary recipients were able to contribute efficiently to myofibers in the muscle tissue of tertiary recipients. Altogether, our data demonstrate that muscle-derived stem cells present a major hematopoietic repopulating ability with evidence of self-replication in vivo. They are radiation-sensitive and similar to marrow-derived stem cells in terms of their ability to generate multilineage hematopoiesis. Finally, our data demonstrate that muscle-derived hematopoietic stem cells do not lose their ability to contribute to myofiber generation after at least two rounds of serial transplantation, suggesting a potential that is probably equivalent to that generated by marrow transplantation. 相似文献
17.
BACKGROUND: Several empirical studies have found temporal lobe impairments in many patients with schizophrenia. The strength and consistency of this evidence, however, has not been evaluated and synthesized quantitatively. Hence, we ask to what extent are temporal cortices really defective in schizophrenia? METHODS: Meta-analytical methods were used to determine the magnitude of evidence in support of structural and physiological temporal-hippocampal system deficits in schizophrenia. We report effect sizes from studies since 1980 that used structural (CT, MRI) and functional (SPECT, PET) neuroimaging methods. RESULTS: Both structural and functional imaging literatures are distinguished by heterogeneity whereby most patients show normative temporal function and structure, a minority shows diminished values and some patients demonstrate augmented function and structure rather than a deficit. CONCLUSIONS: The findings are hard to incorporate within single disease models that propose major involvement of the temporal system in schizophrenia, at least at the degree of resolution obtained with current imaging technology. 相似文献
18.
Rats lever pressed for food and learned new response sequences on three levers. At the beginning of each daily session, responses on only one of the levers produced food. After meeting criterion on one lever, the task was "incremented" so that sequential responses on two levers were required and so on up to five sequential responses. Each new required response was added in front of the previously performed sequence. Sequences of lever presses required to produce food changed each session. Following establishment of stable acquisition behavior, the acute effects of d-amphetamine (0.30-3.0 mg/kg), diazepam (0.125-4.0 mg/kg), morphine (0.30-10.0 mg/kg), pentobarbital (1.0-17.5 mg/kg), and chlorpromazine (0.10-3.0 mg/kg) were examined. All drugs decreased the number of response sequences completed in a dose-dependent fashion. Response rates generally decreased at or below those doses that caused an increase in errors. For d-amphetamine, the profound disruption of incremental repeated acquisition behavior was primarily due to drug-induced perserverative responding. Pentobarbital and chlorpromazine increased errors both when the sequence was incremented and within the sequence whereas diazepam only increased errors when the sequence was incremented. Morphine generally increased within sequence errors without affecting errors when the sequence was incremented. 相似文献
19.
A Quality Assurance Program (QAP) should both evaluate and improve the quality of a service. In order to train newly employed pharmacists and ensure provision of a consistently high level of clinical service, a pharmacist training program for an Aminoglycoside Monitoring Service (AMS) and a QAP involving pharmacist certification was established. The certification program consists of a pretest, a reading/information package, an "on the job" training requirement and a posttest which pharmacists work through at their own speed. Certification requires completion of 45 hours of supervised AMS activity and a score of 90 percent on the posttest. Yearly recertification is required. As an integral part of the QAP, the clinical coordinator reviews the AMS monitoring forms monthly for specific performance standard indicators. Problems are identified and dealt with on an individual basis. The program is not mandatory, however, all pharmacists have elected to complete certification. Seven pharmacists and three pharmacy residents have participated in the certification program. All seven pharmacists and one resident received certification. A questionnaire completed by the pharmacists indicated that all felt certification was necessary and contributed to standardization and consistency of the AMS. 相似文献
20.