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991.
López Sánchez E Francés Muñoz E Mondéjar García JJ España Gregori E Menezo JL 《Archivos de la Sociedad Espa?ola de Oftalmología》2000,75(6):421-424
PURPOSE/METHODS: We present the case of a 69 year-old male patient who developed an anterior pole ischemia syndrome in his right eye. He did not have any personal history of diabetes or previous ocular pathology. Indirect ophthalmoscopy did not show any pathological finding. RESULTS/CONCLUSIONS: Carotid Duplex scanning and Nuclear Magnetic Resonance detected a severe carotid stenosis on the same side, which explained the case. We reviewed different forms of presentation of venous stasis syndrome in carotid stenosis and present this uncommon case of anterior segment ischemia syndrome without posterior segment findings. 相似文献
992.
993.
Schollen E; Pardon E; Heykants L; Renard J; Doggett NA; Callen DF; Cassiman JJ; Matthijs G 《Human molecular genetics》1998,7(2):157-164
The search for the carbohydrate-deficient glycoprotein syndrome type I
(CDG1) gene has revealed the existence of a family of phosphomannomutase
(PMM) genes in humans. Two expressed PMM genes, PMM1 and PMM2 , are located
on chromosome bands 22q13 and 16p13, respectively, and a processed
pseudogene PMM2 psi is located on chromosome 18p. Mutations in PMM2 are the
cause of CDG type IA whereas no disorder has been associated with defects
in PMM1 as yet. Here, we describe the genomic organization of these
paralogous genes. There is a 65% identity of the coding sequence, and all
intron/exon boundaries have been conserved. The processed pseudogene is
more closely related to PMM2 . Remarkably, several base substitutions in
PMM2 that are associated with disease are also present at the corresponding
positions in the pseudogene. Thus, mutations that occur at a slow rate in
the active gene in the population have also accumulated in the pseudogene.
相似文献
994.
Prognostic factors for an unsatisfactory primary methotrexate treatment of cervical pregnancy: a quantitative review 总被引:17,自引:0,他引:17
Hung TH; Shau WY; Hsieh TT; Hsu JJ; Soong YK; Jeng CJ 《Human reproduction (Oxford, England)》1998,13(9):2636-2642
To determine the risks when the primary methotrexate (MTX) treatment of
cervical pregnancy has an unsatisfactory outcome, we conducted a Medline
search on relevant literature published from January 1983 to June 1997. The
search yielded 28 publications of 48 cases of cervical pregnancy. These and
four new cases from our institutions were used in our study. A cervical
pregnancy that presented with a serum beta-human chorionic gonadotrophin
concentration of > or = 10,000 mIU/ml [odds ratio (OR) 10.82, 95%
confidence interval (CI) 2.59, 45.14], gestational age at > or = 9 weeks
(OR 6.44, 95% CI 1.46, 28.52), embryonic cardiac activity (OR 14.29, 95% CI
2.95, 76.92), and crown- rump length of >10 mm (OR 13.33, 95% CI 1.46,
120.48) was considered to be associated with a higher unsatisfactory rate
of primary MTX treatment. A concomitant feticide was found to enhance the
therapeutic effect of MTX treatment if embryonic cardiac activity was
evident (OR 0.13, 95% CI 0.02, 0.68). Administration of a high dose of MTX
did not seem to be more effective than a lower one. Our findings supported
some previous observations and, more importantly, provided useful clinical
information in selecting appropriate candidates for MTX treatment in cases
of cervical pregnancy.
相似文献
995.
Molecular defects in Sanfilippo syndrome type A 总被引:2,自引:2,他引:2
Sanfilippo A syndrome (mucopolysaccharidosis type IIIA, MPS-IIIA) is an
autosomal recessive neurodegenerative disorder due to an enzymatic defect
of the lysosomal enzyme sulphamidase (EC 3.10.1.1) required for the
degradation of heparan sulphate. In this study, molecular defects in the
sulphamidase gene of MPS-IIIA patients were investigated in a group of 10
patients of Australian and American origin. The entire coding region of the
sulphamidase gene was RT-PCR amplified and one polymorphism (R456H), four
novel mutations (S66W, R245H, E447K, 1307 del 9) and one previously
described mutation (1284 del 11) were identified by direct PCR sequencing.
R245H was present in six patients including one severely affected
homozygote. In three of the other patients with R245H, second mutant
alleles were identified as S66W, 1284 del 11 and E447K, respectively. S66W
was also detected in another patient where the other mutant allele remains
undefined. In addition, 1307 del 9 was also detected in a patient with the
other mutant allele remaining undefined. Allele specific oligonucleotide
hybridisation was used to determine the incidence of these in a population
of 26 MPS-IIIA patients (Australian and American) and 60 normal controls
(Australian). R245H represented 27% (14/52 alleles) in this total patient
population, while the other three changes ranged from 1.9 to 9.6% (1-5 of
52 alleles). The sequence variant, R456H, was shown to be polymorphic as it
was present in 55% of normal and 38% of patient alleles. The total combined
incidence of these five is 46% of alleles. This is the first study of the
molecular defects in MPS-IIIA patients and will greatly assist the
development of molecular analysis for MPS-IIIA patients and studies
concerned with genotype to phenotype relationships.
相似文献
996.
mRNA差异显示法筛选和克隆胎肝中差异表达基因 总被引:1,自引:1,他引:0
0 引言 胎肝正处于生长发育阶段 ,其中表达的一些基因在成人肝脏中处于关闭状态 ,当成人肝脏部分切除或肝细胞广泛受损时 ,剩余肝细胞表现出很强的再生能力 ,再生成年肝脏和肝癌细胞中都出现有发育早期基因的表达 [1 ] .克隆这类胎肝中差异表达的基因 ,将有助于了解肝脏的发育过程 ,并为肝脏再生及肝脏相关疾病的研究提供线索 .1 材料和方法1.1 材料 胎肝和成人肝组织分别由西京医院妇产科和肝胆外科提供 .差示 PCR引物为 5′端 10碱基随机引物 I(RPI) :5′- AGCCACCATG- 3′ ;5′端 10碱基随机引物 II(RPII) :5′- TAGCAG… 相似文献
997.
Association of proliferating cell nuclear antigen with cyclin-dependent kinases and cyclins in normal and transformed human T lymphocytes 总被引:4,自引:0,他引:4
The proliferating cell nuclear antigen (PCNA) is an auxiliary protein of DNA polymerase delta and appears to be needed for both DNA synthesis and DNA repair. It is present in low amount in resting normal human T lymphocytes and, upon mitogenic stimulation with phorbol dibutyrate and ionomycin, begins to increase in mid-G1 phase, approximately 12 to 15 hours before entry into S phase. PCNA continues to increase in amount throughout the cell cycle and remains high in proliferating cultures. PCNA was extracted from activated normal T cells and from the transformed T-lymphoblastoid cell line Jurkat by a method that recovered approximately 98% of total cellular PCNA but yet retained its associations with other proteins. PCNA immunoprecipitates possessed H1 histone kinase activity, which increased in parallel with increasing cellular content of PCNA. Both the cdc2 and cdk2 kinases were found associated with PCNA in normal T cells, in amounts consistent with detected kinase activity. The results indicate that PCNA is not an inhibitory molecule of cdk/cyclin activity. Both normal and transformed T cells contained PCNA in association with cdk2, cdk4, cdk5, and cdk6, with the amount of PCNA associated with these molecules increasing in the order listed. Relatively high amounts of PCNA were also found associated with cyclins D2 and D3, the major cyclin partners of cdk6 in T cells. Though detected in normal cells, PCNA/cdc2 complexes were present in exceedingly low amount, if at all, in Jurkat cells. This cell line appeared to contain more of nearly all of the cdk and cyclin molecules analyzed, but there seemed to be little difference in the patterns of association of these molecules with PCNA in the cell line as compared with normal human T cells. 相似文献
998.
Saelman EU; Horton LF; Barnes MJ; Gralnick HR; Hese KM; Nieuwenhuis HK; de Groot PG; Sixma JJ 《Blood》1993,82(10):3029-3033
The aim of this investigation was to identify domains of collagen type I that can support platelet adhesion under flow conditions. Four cyanogen bromide (CB) fragments composing 87% of the collagen alpha 1(I)-chain were studied under static and flow conditions. Under static conditions, bovine and human collagen fragment alpha 1(I)CB3 induced aggregate formation, whereas alpha 1(I)CB7 and alpha 1(I)CB8 supported adhesion of dendritic and contact platelets. Bovine alpha 1(I)CB6 weakly supported platelet adhesion. At shear rate 300/s, collagen fragment alpha 1(I)CB3 strongly supported platelet adhesion, whereas lower platelet adhesion was observed to alpha 1(I)CB7 and alpha 1(I)CB8. The fragment alpha 1(I)CB6 did not support platelet adhesion under flow conditions. Adhesion to alpha 1(I)CB3 was completely inhibited by a low concentration (0.6 IgG microgram/mL) of anti-GPIa monoclonal antibody (MoAb), whereas this concentration of antibody partially inhibited adhesion to alpha 1(I)CB7 and alpha 1(I)CB8. At higher concentrations (3 micrograms/mL) the anti-glycoprotein Ia (GPIa) antibody completely inhibited adhesion to alpha 1(I)CB8 and further reduced adhesion to alpha 1(I)CB7. Platelet adhesion to alpha 1(I)CB3, alpha 1(I)CB7, and alpha 1(I)CB8 was strongly inhibited by an anti-GPIb MoAb. A MoAb against the GPIb-binding site of von Willebrand factor (vWF) strongly inhibited platelet adhesion to alpha 1(I)CB7 and alpha 1(I)CB8, whereas platelet adhesion to alpha 1(I)CB3 was not inhibited. We conclude that under flow conditions alpha 1(I)CB3, alpha 1(I)CB7, and alpha 1(I)CB8 support GPIa/IIa-dependent platelet adhesion. The GPIb-vWF interaction is important under flow conditions for adhesion to alpha 1(I)CB7 and alpha 1(I)CB8 and probably also to alpha 1(I)CB3. 相似文献
999.
Oral iloprost in Raynaud's phenomenon secondary to systemic sclerosis: a multicentre, placebo-controlled, dose-comparison study 总被引:3,自引:2,他引:3
Black CM; Halkier-Sorensen L; Belch JJ; Ullman S; Madhok R; Smit AJ; Banga JD; Watson HR 《Rheumatology (Oxford, England)》1998,37(9):952-960
OBJECTIVE: To identify the optimal dose of oral iloprost on the basis of
efficacy and tolerability in patients with Raynaud's phenomenon secondary
to systemic sclerosis. DESIGN: Multicentre, randomized, parallel-group
comparison of two different doses of oral iloprost and placebo. SETTING:
European university hospitals. PATIENTS: A total of 103 patients with
Raynaud's phenomenon secondary to systemic sclerosis. INTERVENTION:
Patients received one of three treatments for 6 weeks: placebo, oral
iloprost 50 microg or oral iloprost 100 microg. Each treatment was taken
twice daily, giving total daily doses of iloprost of 100 and 200 microg.
MEASUREMENTS: The frequency, total daily duration and severity of Raynaud's
attacks were recorded in a specially designed patient diary; physician's
global assessment and adverse events were recorded at visits to the clinic.
Analysis was performed on an intention-to-treat population. RESULTS: A
total of 103 patients were recruited, 89 completed the assessments
throughout the treatment period and 82 completed an additional 6 weeks of
follow-up after treatment. Thirty-five patients received placebo, 33
received iloprost 50 microg and 35 received iloprost 100 microg. The mean
percentage reductions in the frequency, total daily duration and severity
of Raynaud's attacks were numerically greater in the iloprost groups at the
end of treatment and at the end of follow-up. At the end of treatment (6
weeks), there were significant treatment differences in the total daily
duration of attacks (P = 0.03), but not in the severity (P = 0.07) or the
frequency of attacks (P = 0.37). At the end of follow-up (12 weeks), there
were significant treatment differences in the total daily duration of
attacks (P = 0.001) and in the severity of attacks (P = 0.007), but not in
the frequency of attacks (P = 0.07). Percentages of patients improved at
the end of treatment as assessed by the physician were 44% placebo, 57%
iloprost 50 microg and 64% iloprost 100 microg (not significant).
Side-effects were reported by 80% of patients on placebo, 85% on oral
iloprost 50 microg and 97% on oral iloprost 100 microg. Premature
discontinuations of treatment in each group were 9, 30 and 51%,
respectively, with 6, 27 and 51% being due to adverse events. CONCLUSION:
The results on the daily duration of Raynaud's attacks suggest that both 50
and 100 microg oral iloprost twice daily may be effective in the treatment
of Raynaud's phenomenon secondary to systemic sclerosis. The 50 microg
iloprost dose was better tolerated in this patient group.
相似文献
1000.
The gene located at chromosome 18 band q21 is rearranged in uncultured diffuse lymphomas as well as follicular lymphomas 总被引:6,自引:0,他引:6
Lee MS; Blick MB; Pathak S; Trujillo JM; Butler JJ; Katz RL; McLaughlin P; Hagemeister FB; Velasquez WS; Goodacre A 《Blood》1987,70(1):90-95
The karyotypic abnormality t(14;18)(q32;q21) is reported to occur in 75% of follicular lymphomas. This translocation results in the rearrangement of a putative oncogene bcl-2, which resides at chromosome 18 band q21 (the 18q21 gene). Using two human genomic DNA fragments cloned from the chromosome 18 band q21 as probes, we analyzed 65 uncultured human lymphoma samples by the Southern blot technique. The 18q21 gene was rearranged in 18 of 26 (69%) follicular lymphomas, 3 of 5 (60%) follicular lymphomas transformed to large cell lymphomas, 8 of 20 (40%) diffuse large cell lymphomas (DLCLs), and 2 of 7 (29%) small noncleaved cell lymphomas (SNCs). Our analysis detected rearrangement of the 18q21 gene in 10 of 13 (77%) cases in which the t(14;18)(q32;q21) translocation was found by cytogenetic techniques. Our analysis also proved helpful in difficult karyotyping situations: (a) identifying the donor chromosome fragment as chromosome 18 band q21 in 4 of 9 (44%) cases that cytogenetically displayed a 14q+ chromosome of unknown origin, and (b) identifying a rearrangement of chromosome 18 band q21 in 12 of 18 (67%) cases that cytogenetically yielded no cells in metaphase. We also demonstrated three cases of submicroscopic rearrangement of the 18q21 gene. In our studies, patients with DLCLs and rearrangement of the 18q21 gene had a significantly higher incidence of extranodal involvement when compared with patients with DLCLs and no 18q21 gene rearrangement (P = 0.03). 相似文献