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The junctional zone (Jz) of the mouse placenta consists of two main trophoblast populations, spongiotrophoblasts and glycogen cells (GCs), but the development and function of both cell types are unknown. We conducted a quantitative analysis of GC size, number, and invasion of cells into the decidua across gestation. Furthermore, we identified markers of GC function to investigate their possible roles in the placenta. While the spongiotrophoblast cell volume doubles, and cell number increases steadily from E12.5 to E16.5, there is a remarkable 80-fold increase in GC numbers. This finding is followed by a notable decrease by E18.5. Surprisingly, the accumulation of GCs in the decidua did not fully account for the decrease in GC number in the Jz, suggesting loss of GCs from the placenta. Glucagons were detected on GCs, suggesting a steady glucose release throughout gestation. Connexin31 staining was shown to be specific for GCs. GC migration and invasion may be facilitated by temporally regulated expression of matrix metalloproteinase 9 and the imprinted gene product, Decorin. Expression of the clearance receptor for type II insulin-like growth factor (IGF-II), IGF2R, in a short developmental window before E16.5 may be associated with regulating the growth effects of IGF-II from glycogen cells and/or labyrinthine trophoblast on the expansion of the Jz. Thus stereology and immunohistochemistry have provided useful insights into Jz development and function of the glycogen cells. 相似文献
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As more patients survive cancer, and as more sophisticated multidrug antineoplastic protocols are developed, the chances of an anesthesiologist's coming into contact with patients who have been treated with such protocols are increasing. The anesthesiologist who must administer anesthesia to a patient who has had chemotherapy must be cognizant of the particular antineoplastic agents that have the potential for producing occult pulmonary dysfunction. Anesthetic management of these cases must be carefully planned and titrated to prevent further lung injury. 相似文献
5.
S. G. George J. Wright J. Conroy 《Archives of environmental contamination and toxicology》1995,29(4):530-534
Activities of the petroleum-inducible mixed function oxygenase CYP1A (EROD) were measured in livers of inshore demersal fish species at various sites around the coast of Shetland to determine the sub-lethal impact of oil spilled after the wreck of the tanker M.V. Braer in January 1993. Visible coastal pollution by the oil was only apparent for some two weeks after the incident and tissue PAH levels in muscle of gadoid fish such as rockling from these areas were not elevated 3 months afterwards, while hepatic EROD activities were elevated some 7-to 9-fold. A 6.5-fold elevation was still observed 5 months afterwards; however, the levels had returned to those of fish from non-polluted environments 7 months after the incident and remained at baseline levels after the following winter's storm action. These data demonstrate the usefulness of enzymatic analysis as a sensitive method for assessing the temporal and spatial impact of an oil spill. 相似文献
6.
Fatal occupational injuries in the United States, 1980 through 1985 总被引:12,自引:0,他引:12
The National Traumatic Occupational Fatality surveillance project was designed to gather demographic, employment, and injury information from death certificates for all deaths due to injuries at work in the United States. Approximately 7000 workers have died each year during the 6-year period from 1980 through 1985: 94% were men, and 6% were women. Unintentional injuries caused the deaths of 83% of the men and 50% of the women. Eleven percent of the men and 39% of the women died from homicide. While the greatest number of deaths occurred in the group aged 20 through 34 years, fatality rates were highest among those aged 70 years and older. Expressed as deaths per 100,000 workers, annual fatality rates for black workers (7.7) were slightly higher than for white workers (6.5). The four industrial groups with the highest fatality rates were mining (31.9); transportation, communication, and public utilities (25.4); construction (24.0); and agriculture, forestry, and fishing (20.7). From 1980 through 1985 the annual traumatic occupational fatality rate fell 23%. 相似文献
7.
M. O’Mahony R. Conroy E. Shelley N. Hickey A. Radic 《Irish journal of medical science》1991,160(9):17-21
A myocardial infarction and stroke register was established in January 1987 as part of the evaluation of the Kilkenny Health
Project This is a community programme which aims to reduce risk factors for coronary heart disease. The register records acute
myocardial infarction and stroke in residents of County Kilkenny and of the reference county. This will provide accurate estimates
of the incidence of these diseases and of trends over time.
Methods used comply with the protocol in use by the WHO MONICA Project. This will allow comparison of the incidence of coronary
heart disease and stroke in this register with that in other MONICA locations, including that in Belfast, Northern Ireland. 相似文献
8.
Katharina Domschke Karen Sheehan Naomi Lowe Aiveen Kirley Celine Mullins Roderick O'sullivan Christine Freitag Tim Becker Judith Conroy Michael Fitzgerald Michael Gill Ziarih Hawi 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2005,(1):110-114
Pharmacological and genetic studies suggest the importance of the dopaminergic, serotonergic, and noradrenergic systems in the pathogenesis of attention deficit hyperactivity disorder (ADHD). Monoamine oxidases A and B (MAO-A and MAO-B) degrade biogenic amines such as dopamine and serotonin and thereby control the levels of these neurotransmitters in the central nervous system. We examined four polymorphisms in the MAO-A gene (30 bp promoter VNTR, CA microsatellite in intron 2, 941G/T SNP in exon 8, and A/G SNP in intron 12) as well as two markers in the MAO-B gene (CA microsatellite in intron 2 and T/C SNP in intron 13) for association with ADHD in an Irish sample of 179 nuclear families. TDT analysis of the examined MAO-A markers revealed a significant association of the more active MAO-A 941G allele with the disorder (chi2 = 5.1, P = 0.03, OR = 1.7). In addition, haplotype analysis revealed a significantly increased transmission of a haplotype consisting of the shorter allele of the promoter VNTR (allele 1), the 6-repeat allele of the CA microsatellite and the G-allele of the 941G/T SNP (famhap global statistic 34.54, P = 0.01) to ADHD cases. No significant distortion in the number of transmitted alleles was observed between the two examined MAO-B polymorphisms and ADHD. These findings suggest the importance of the 941G/T MAO-A polymorphism in the development of ADHD at least in the Irish population. 相似文献
9.
Bacterial growth and killing in chronic ambulatory peritoneal dialysis fluids. 总被引:10,自引:3,他引:10 下载免费PDF全文
We determined the ability of Staphylococcus epidermidis, Staphylococcus aureus, and Escherichia coli to survive and grow in peritoneal dialysis fluids from patients undergoing chronic ambulatory peritoneal dialysis. Staphylococci did not survive in commercially available dialysis solutions but grew readily in peritoneal effluents obtained from patients after the dialysis dwell time. The number of CFU doubled 6 and 13 times in 24 h for S. epidermidis and S. aureus, respectively. E. coli grew well in both the pre- and postdialysis peritoneal fluid. Peritoneal macrophages as well as peripheral blood leukocytes inhibited bacterial growth in peritoneal dialysis fluid. However, 10(6) phagocytes per ml were minimally required to obtain a bacteriostatic effect. The addition of serum to peritoneal dialysis fluid increased the antibacterial activity of macrophages and blood leukocytes. The capacity of the aminoglycoside antibiotic tobramycin to reduce bacterial CFU in peritoneal dialysis fluid was only 10% of its bactericidal capacity in standard Mueller-Hinton brush. Peritoneal dialysis fluid had no effect on the antibacterial activity of imipenem. 相似文献
10.
Paul K. Hildebrandt James D. Conroy Adam E. McKee M. B. A. Nyindo David L. Huxsoll 《Infection and immunity》1973,7(2):265-271
The ultrastructure of Ehrlichia canis was examined in both pulmonary mononuclear cells and in monocytes cultured from an infected dog. The cytoplasmic inclusions, or morulae, of E. canis consisted of a membrane-lined vacuole-containing elementary bodies which varied in size and number. The elementary bodies were bound by two trilamellar membranes. The organism shared morphological properties of both the genus Rickettsia and genus Chlamydia. 相似文献