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排序方式: 共有6525条查询结果,搜索用时 984 毫秒
51.
52.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
53.
Immune reactions associated with silicone-based ventriculo-peritoneal shunt malfunctions in children
VandeVord PJ Gupta N Wilson RB Vinuya RZ Schaefer CJ Canady AI Wooley PH 《Biomaterials》2004,25(17):3853-3860
The implantation of ventriculo-peritoneal (VP) shunting systems is the most commonly performed neurological procedure in children with hydrocephalus. Although the overall complication risk is low, the cumulative risk of shunt failure is high and unfortunately results in a high prevalence of revision surgeries. In this study, we explored the concept that some pediatric patients may develop an immune response to either the proteins attached to the silicone implant surface or to the biomaterial itself, and that this reaction may contribute to VP shunt failure in some individuals. The data displays that the sterile shunt malfunction group had a higher rate of protein deposition and increased levels of autoantibodies to the extracted surface proteins as compared to individuals with functioning shunting systems. The precise nature of the shunt-bound proteins that serve as antigens in this experiment have not yet been determined. The data also indicated that some individuals develop antibodies to polymeric substances that cross-react with partially polymerized acrylamide. The detection of significant amounts of shunt-bound protein, antibody responses to these proteins and to polymeric substances suggest that an immunological response to these proteins may play a role in the mechanism behind sterile shunt malfunctions. 相似文献
54.
Localization of a gene for otosclerosis to chromosome 15q25-q26 总被引:5,自引:0,他引:5
Tomek MS; Brown MR; Mani SR; Ramesh A; Srisailapathy CR; Coucke P; Zbar RI; Bell AM; McGuirt WT; Fukushima K; Willems PJ; Van Camp G; Smith RJ 《Human molecular genetics》1998,7(2):285-290
Among white adults otosclerosis is the single most common cause of hearing
impairment. Although the genetics of this disease are controversial, the
majority of studies indicate autosomal dominant inheritance with reduced
penetrance. We studied a large multi- generational family in which
otosclerosis has been inherited in an autosomal dominant pattern. Five of16
affected persons have surgically confirmed otosclerosis; the remaining nine
have a conductive hearing loss but have not undergone corrective surgery.
To locate the disease- causing gene we completed genetic linkage analysis
using short tandem repeat polymorphisms (STRPs) distributed over the entire
genome. Multipoint linkage analysis showed that only one genomic region, on
chromosome 15q, generated a lod score >2.0. Additional STRPs were typed
in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and
D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis
gene.
相似文献
55.
56.
Settmacher B Rheinheimer C Hamacher H Ames RS Wise A Jenkinson L Bock D Schaefer M Köhl J Klos A 《European journal of immunology》2003,33(4):920-927
The anaphylatoxic peptide C3a is a pro-inflammatory mediator generated during complement activation, whose specific G protein coupled receptor is expressed on granulocytes, monocytes, mast cells, activated lymphocytes, and in the nervous tissue. We have generated RBL-2H3 cell clones stably expressing mutants of the human C3a-receptor (C3aR) with combined alanine (Ala) substitutions of ten C-terminal serine (Ser) or threonine (Thr) residues, which may represent putative phosphorylation sites to characterize their role in ligand-induced C3aR internalization and signaling. Ser475/479 and Thr480/481 as well as Ser449 seemed not to be involved in ligand-induced receptor internalization. Either directly or by a conformational change they even "inhibit" C3aR internalization. In contrast, mutants with Ala substitutions at Ser465/470 and Thr463/466 were poorly internalized, and Thr463 seemed to be the most important C-terminal Thr or Ser residue directly effecting receptor internalization. However, it is likely that other C3aR regions additionally participate in this negative feed-back mechanism since even mutants with multiple Ala substitutions still internalized to a limited degree. Interestingly, in a mutant with a single exchange of Ser449 to Ala, the signal transduction assessed by a Ca(2+) assay and [(35)S]GTP gamma S-binding on HEK cells transiently co-transfected with G-alpha 16 or G-alpha O, respectively, was severely impaired, indicating that this residue of C3aR is involved in G protein coupling. 相似文献
57.
K. Schaefer H. -U. Koch A. Opitz D. von Herrath H. Knoop 《Journal of molecular medicine (Berlin, Germany)》1970,48(18):1129-1131
Zusammenfassung Es wurden Untersuchungen über den Langzeitmetabolismus von Vitamin D bei Normalpersonen und Patienten mit Niereninsuffizienz durchgeführt. Nach intravenöser Injektion von Vitamin D3-H3 zeigte sich in den untersuchten Serumproben weder für die Halbwertszeit noch für die Verteilung von Vitamin D und seinen verschiedenen Metaboliten ein Unterschied zwischen den beiden Gruppen. Diese Untersuchungsergebnisse machen es sehr unwahrscheinlich, daß eine Vitamin D-Stoffwechselstörung für die Entwicklung der azotämischen Osteopathie verantwortlich ist.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Summary Investigations have been performed in normal subjects and renal patients on the long term metabolism of vitamin D3. After an intravenous injection of tritiated vitamin D3 there was no difference between both groups: halflife and the distribution of vitamin D and its various metabolites in the serum were almost identical. Our results suggest that a disorder of vitamin D metabolism is not responsible for the development of the azotemic osteodystrophy.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
58.
Giardia lamblia cysts obtained from human symptomatic and asymptomatic donors were excysted in vitro. Excystation averaged 87% for cysts from symptomatic donors and 70% for cysts from asymptomatic donors. 相似文献
59.
Contraceptive potential of a mifepristone-nomegestrol acetate sequential regimen in women 总被引:1,自引:0,他引:1
Croxatto HB; Salvatierra AM; Fuentealba B; Massai R 《Human reproduction (Oxford, England)》1998,13(12):3297-3302
The effectiveness of a sequential regimen consisting of mifepristone, 10
mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for
the next 13 days, for inhibiting ovulation and maintaining regular bleeding
cycles was assessed in 10 surgically sterilized volunteers who were
followed for one pretreatment and three treated cycles. Hormonal
determinations in blood and urine, ovarian ultrasonography, bleeding
records in all cycles and an endometrial biopsy taken on day 22-25 of the
third treatment cycle were used to monitor the effects of treatment. During
treatment, 24 monophasic (no sustained progesterone rise above 12 nmol/l)
and six biphasic cycles were recorded. Nine follicular ruptures were
detected echographically in these 30 treated cycles, five of which occurred
in monophasic cycles. All follicular ruptures occurred on days 1-7 of NOMA
treatment. Echographic and endocrine features of ovulatory cycles were both
present in only four treated cycles (13.3%). Development of a secretory
endometrium was achieved in all cases, but it was always irregular. Regular
withdrawal bleeding occurred in all subjects and no adverse reactions were
recorded. The ovarian and endometrial effects of this regimen justify
testing its contraceptive effectiveness in phase 2 clinical trials.
相似文献
60.
A Srour AM El Tantawi N Khouja A Zouaoui J-P Lassau J Philippon Ph Cornu 《Surgical and radiologic anatomy : SRA》1994,16(1):117-119
Summary The anterior interhemispheric approach for aneurysms of the anterior communicating artery was studied in ten cadavers. This approach presents several advantages over the pterional approach widely used in neurosurgery. It allows direct access to the region of the anterior communicating artery complex with minimal retraction of the brain and preservatioin of the olfactory tract and the gyrus rectus.
Bases anatomiques de l'abord inter-hémisphérique antérieur lors de la chirurgie des anévrysmes de l'artère communicante antérieure
Résumé Ce travail concerne l'abord neurochirurgical des anévrysmes de l'artére communicante antérieure par voie frontale interhémisphérique. L'étude anatomique a été réalisée sur dix sujets. Cette exposition possède de nombreux avantages comparée à la voie ptérionale habituelle : voie d'abord reduite médiane permettant une visualisation directe et symétrique du complexe artériel de l'artére communicante antérieure ; avec le moindre manipulation et retraction du cerveau en respectant les voies olfactives et le gyrus rectus.相似文献