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991.
Refining the genetic location of the gene for X linked hydrocephalus within Xq28. 总被引:3,自引:4,他引:3
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M Jouet E Feldman J Yates D Donnai J Paterson D Siggers S Kenwrick 《Journal of medical genetics》1993,30(3):214-217
The most common inherited form of hydrocephalus, X linked hydrocephalus (HSAS), is characterised by mental retardation, adducted thumbs, and spastic paraplegia. Genetic analysis has mapped the locus for HSAS to subchromosomal band Xq28 within a region of approximately 2 megabases of DNA. In order to refine the location of the disease gene we have conducted genetic linkage analysis with Xq28 marker loci in four additional HSAS families. A lod score of 4.26 with polymorphic marker DXS52 (St14) confirms the linkage of HSAS to Xq28. Identification of a recombination event between the HSAS gene and Xq28 loci F8C and DXS605 (2-19) reduces the size of the interval likely to contain the disease locus to about 1.5 megabases, the distance between DXS605 and DXS52. The locus for neural cell adhesion molecule, L1CAM, maps within this interval and therefore represents a candidate gene for HSAS. 相似文献
992.
A human dispermic chimaera first suspected from analyses of the blood group gene-specified glycosyltransferases 总被引:1,自引:0,他引:1
W M Watkins A D Yates P Greenwell G W Bird M Gibson T C Roy J Wingham W Loeb 《Journal of immunogenetics》1981,8(2):113-128
The red cells of a normal male blood donor, K.S., were first grouped as B but he was found to lack anti-A in his serum. Closer investigation revealed that his red cells had very weak A activity, demonstrable only by absorption and elution of anti-A. He is a non-secretor of ABH and a secretor of Lea. Blood group A-, B and H-gene specified glycosyltransferases were detected in his serum. In contrast to the finding of a B antigen of normal strength on his red cells, the B transferase in his serum was only about 30% of the normal level and, despite the very weak A activity of K.S's red cells, the A transferase level was about 50% of that found in the serum of group A individuals with normal strength of A antigen. Moreover, the A transferase on the basis of its pH optimum, Km values for donor and acceptor substrates, activation by divalent cations, isoelectric focusing profile and capacity to convert O to A-active cells, was characterized as the product of an A1 gene. A family study showed that K.S's wife is group A2 and that they have two sons, one group A2 and the other group B. The group B son is assumed to have inherited a B gene from the propositus but the level of B transferase in the son's serum is three times as high as that in his father's serum. The wife of the propositus and his group A2 son have normal A2 transferases in keeping with their A2 red cell status. The A2 son therefore appears to have inherited an A2 gene from his mother but neither the A1 nor the B gene shown to be carried by his father. The distribution of transferase activities in K.S's red cells differs from that in his serum. A level of B transferase within the normal range was found in his red cell membranes but a very low level of A transferase was detected. The discrepancies between the serum transferases and ABO red cell group, together with the pattern of inheritance within the family, led to a suspicion of chimaerism. This was confirmed by the finding of fibroblasts with the female 46XX karyotype in cultures of the propositus' skin. These results suggest that K.S. is a dispermic chimaera with two different cell lines of the genotypes BO and A1O or A1A1. The group A2 son is assumed to have inherited an O gene from his father. It seems probable that K.S.'s bone marrow and reproductive organs are comprised predominantly of the XY cell line which carried the blood group BO genotype whereas his skin and other tissues which contribute the A1 transferase to his plasma, are partly made up of the XX cell line which carries the blood group A1O or A1A1 genotype. 相似文献
993.
Evaluation of a rapid PCR-based epidemiological typing method for routine studies of Mycobacterium tuberculosis 总被引:2,自引:0,他引:2
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Restriction fragment length polymorphism (RFLP) based on the insertion sequence IS6110 is used to investigate episodes of suspected transmission of infection of tuberculosis but usually takes a number of weeks from receipt of request to obtain a result. Often investigations would benefit from a more rapid method, possibly one containing an amplification step. The method employed uses a simple DNA extraction followed by a PCR step involving a single primer. Restriction enzyme analysis was performed when the patterns obtained from the PCR products were indistinguishable, especially when only single similar-size bands were obtained. The isolates used were strains of Mycobacterium tuberculosis submitted for epidemiological investigations as part of (i) possible contact-outbreak (22 episodes involving between 2 and 20 patients), (ii) possible incidents of laboratory cross-contamination (21 episodes), and (iii) possible change in drug resistance pattern or a case of reinfection (1 patient). The PCR products giving similar patterns were then subjected to restriction enzyme analysis. In conclusion it has been shown that this method is rapid, with results within 1 to 2 days of the request being received; is reproducible; and gives the same results as does RFLP. The restriction enzyme analysis stage has improved the efficiency of the technique. 相似文献
994.
Over-representation of PPARgamma sequence variants in sporadic cases of glioblastoma multiforme: preliminary evidence for common low penetrance modifiers for brain tumour risk in the general population
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Zhou XP Smith WM Gimm O Mueller E Gao X Sarraf P Prior TW Plass C von Deimling A Black PM Yates AJ Eng C 《Journal of medical genetics》2000,37(6):410-414
PPARγ, the gamma isoform of a family of peroxisome proliferator activated receptors, plays a key role in adipocyte differentiation. Recently, its broad expression in multiple tissues and several epithelial cancers has been shown. Further, somatic loss of function mutations in PPARγ have been found in primary colorectal carcinomas. We sought to determine if somatic high penetrance mutations in this gene might also play a role in glioblastoma multiforme (GBM). We also examined this gene to determine if common low penetrance polymorphic alleles might lend low level susceptibility to GBM in the general population. No somatic high penetrance mutations were detected in 96 sporadic GBMs. However, polymorphic alleles at codons 12 and 449 were significantly over-represented among the 27 unrelated American patients with sporadic GBM compared to 80 race matched controls. While nine (33%) were heterozygous for the P12A variant, c.34C/G (cytosine to guanine change at nucleotide 34), 12 (15%) controls were heterozygous for P12A (p<0.05). Similarly, 13 of 26 (50%) glioblastoma patients compared to 10 of 80 (12%) normal controls were found to have the heterozygous H449H polymorphism (p<0.001). The over-representation of H449H in glioblastoma patients was confirmed with a second validation set of American patients. When both American series were combined, polymorphic H449H was over-represented among cases versus controls (p<0.001) and there was a similar trend (p=0.07) for P12A. The precise mechanism for this association is unknown but these PPARγ polymorphisms may be acting in a low penetrance predisposing manner. However, these associations were not found in a German population, possibly arguing that if these variants are in linkage disequilibrium with a third locus, then this effect is relatively new, after the settlement of the American colonies.
Keywords: peroxisome proliferator activated receptors; sequence variants; tumour suppressor 相似文献
Keywords: peroxisome proliferator activated receptors; sequence variants; tumour suppressor 相似文献
995.
J R Yates J P Warner J A Smith F Deymeer J P Azulay I Hausmanowa-Petrusewicz J Zaremba J Borkowska N A Affara M A Ferguson-Smith 《Journal of medical genetics》1993,30(2):108-111
Emery-Dreifuss muscular dystrophy (EMD) is characterised by (1) early contractures of the Achilles tendons, elbows, and postcervical muscles, (2) slowly progressive muscle wasting and weakness with a predominantly humeroperoneal distribution in the early stages, and (3) cardiomyopathy with conduction defects and risk of sudden death. Inheritance is usually X linked recessive but can be autosomal dominant. Family linkage studies have mapped X linked EMD to the distal long arm of the X chromosome but precise genetic localisation has been hampered by the rarity of this condition. We report three new families with X linked Emery-Dreifuss muscular dystrophy studied with DNA markers from Xq27-qter and three previously published families typed for additional markers. No recombination was observed with the red/green cone pigment locus, RGCP (lod score, Z = 2.46), the factor VIII coagulant gene locus, F8C (Z = 6.39), or with DXS115 (Z = 4.94). Two recombinants were observed which mapped EMD distal to DXS15 (DX13) and DXS52 (St14) respectively. Multipoint linkage analysis gave odds exceeding 200:1 for EMD being distal to these markers. A multipoint analysis incorporating published data gave the map cen-DXS304-9cM-DXS15-3cM-DXS52-2 cM-(RGCP,EMD)-3cM-F8C-2cM-DXS115 with odds of 120:1 in favour of a location for EMD between DXS52 and F8C as compared to the next best position distal to F8C. 相似文献
996.
J. R. Wright Jr A. J. Yates H. M. Sharma C. Shim R. L. Tigner P. Thibert 《The American journal of pathology》1982,108(1):72-79
Complete gross and microscopic postmortem examinations were performed on 100 BB Wistar diabetic rats, 27 BB Wistar nondiabetic siblings, and 41 Wistar rats, and the incidence of testicular lesions was tabulated. Testicular atrophy was the predominant finding in all three groups of rats, but atrophy occurred at a much younger age in the diabetic rats. There was a strong relationship between the duration of diabetes and the presence of atrophy, which was stronger than the relationship between age and atrophy. The testicular atrophy observed in the diabetic rats was morphologically similar to the senile testicular atrophy in the nondiabetic rats. Histologic findings that were associated with increasing severity of atrophy were multinucleated giant cells in the lumens of seminiferous tubules, increased interstitial connective tissue, Leydig cell hyperplasia, and thickening of the tunica albuginea. Testicular atrophy has also been reported in human diabetics. Therefore, the BB Wistar rat may be a useful model for investigating this aspect of diabetes mellitus. 相似文献
997.
Previous research suggests an association between partner violence and child behavior problems. However, methodological shortcomings have precluded the formation of directional conclusions. These limitations include failure to control for the effects of child physical abuse and general life stress, employment of nonrepresentative samples from battered women's shelters, and reliance on a single contemporaneous reporter, usually the mother, for information on both independent and dependent measures. This study used prospective, longitudinal data (N = 155) and multiple informants to examine the relation between maternal reports of partner violence in the homeand teacher- and youth-report ratings of concurrent and prospective child behavior problems. Hierarchical multiple regression analyses were used to control for the effects of child physical abuse, child physical neglect, socioeconomic status, child cognitive ability, and life stress. The contribution of partner violence to child behavior problems was confirmed for boys' (n = 81) externalizing problems and girls' (n = 74) internalizing problems. Child developmental status at the time of exposure further influenced these relations. For boys, behavior problems in middle childhood were most strongly related to contemporaneous partner violence, whereas behavior problems among both boys and girls at age 16 were most strongly related to partner violence exposure during the preschool years. 相似文献
998.
Yates JR; van Bakel I; Sepp T; Payne SJ; Webb DW; Nevin NC; Green AJ 《Human molecular genetics》1997,6(13):2265-2269
We have investigated a family in which three siblings with the autosomal
dominant disorder tuberous sclerosis had unaffected parents. The family
were typed for polymorphic markers spanning the two genes known to cause
tuberous sclerosis located at 9q34 (TSC1) and 16p13.3 (TSC2). TSC1 markers
showed different maternal and paternal haplotypes in affected children,
excluding a mutation in TSC1 as the cause of the disease. For the TSC2
markers all the affected children had the same maternal and paternal
haplotypes, as did three of their unaffected siblings. Mutation screening
by RT-PCR and direct sequencing of the TSC2 gene identified a 4 bp
insertion TACT following nucleotide 2077 in exon 18 which was present in
the three affected children but not in five unaffected siblings or the
parents. This mutation would cause a frameshift and premature termination
at codon 703. Absence of the mutation in lymphocyte DNA from the parents
was consistent with germline mosaicism and this was confirmed by our
finding of identical chromosome 16 haplotypes in affected and unaffected
siblings, providing unequivocal evidence of two different cell lines in the
gametes. Molecular analysis of the TSC2 alleles present in the affected
subjects showed that the mutation had been inherited from the mother. This
is the first case of germline mosaicism in tuberous sclerosis proven by
molecular genetic analysis and also the first example of female germline
mosaicism for a characterized autosomal dominant gene mutation apparently
not associated with somatic mosaicism.
相似文献
999.
Thirty-eight patients with palindromic rheumatism were reviewed. A questionnaire was compiled to elucidate prognostic factors in the pattern of disease. Over the period of follow-up 6 patients had developed rheumatoid arthritis, 25 remained palindromic, 3 were in remission of symptoms for over a year, 1 developed ankylosing spondylitis, 1 systemic lupus erythematosus and 2 a non-specific polyarthritis. The duration and interval between attacks was variable and did not differ significantly between the palindromic and rheumatoid groups. All patients who developed rheumatoid had a combination of morning stiffness and pain in several joints at once, whereas only 28% of the palindromics did so, (p <0.01). There was a tendency for episodes of joint pain to occur with increasing frequency and for the plasma viscosity to be persistently elevated in those who developed rheumatoid arthritis. Neither a family history of rheumatoid arthritis nor a positive serum rheumatoid factor test at presentation were of prognostic significance. Oral analgesics or symptomatic measures for the relief of joint pain were effective in the majority of patients.
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相似文献1000.
M Sabatini A J Yates I R Garrett J Chavez J F Dunn L Bonewald G R Mundy 《Laboratory investigation; a journal of technical methods and pathology》1990,63(5):676-682
The rat Leydig cell tumor is a well characterized model of the humoral hypercalcemia of malignancy. The studies reported here were provoked by the observation that tumor-bearing rats become extremely cachectic and develop hypertriglyceridemia as they become hypercalcemic. Since the bone resorbing cytokine tumor necrosis factor (TNF)/cachectin is associated with cachexia and hypertriglyceridemia, we examined hypercalcemic tumor-bearing rats for evidence of increased TNF production using a TNF radioimmunoassay. We found that immunoreactive TNF was increased in the plasma of tumor-bearing rats. The increase in plasma TNF was comparable to that previously shown in hypercalcemic nude mice bearing Chinese hamster ovarian cell tumors transfected with the human TNF gene. There was no detectable TNF activity in tumor culture media which suggested that the tumor itself was not the source of excess TNF production. However, we found that tumor cell conditioned media enhanced the production of TNF activity by normal macrophages in vitro, indicating that increased TNF production in vivo may result from a tumor factor(s) which stimulates TNF production by normal immune cells. When TNF was added together with tumor products to organ cultures of fetal rat long bones, osteoclastic bone resorption was potentiated. These data are consistent with the concept that in this model of the humoral hypercalcemia of malignancy, increased TNF production by normal immune cells is increased, has systemic effects as suggested by cachexia and hypertriglyceridemia, and may work in concert with factors produced directly by tumor cells to overwhelm normal calcium homeostasis. 相似文献