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991.
Analysis of VH genes used by neoplastic B cells in endemic Burkitt's lymphoma shows somatic hypermutation and intraclonal heterogeneity 总被引:6,自引:2,他引:4
Tumor cell lines from six typical cases of endemic Epstein-Barr virus (EBV) genome-positive Burkitt's lymphoma (BL) have been investigated for usage and mutational pattern of Ig VH genes. The neoplastic cells all had a t(8;14) (q24;q32) translocation involving the c-myc protooncogene. The VH genes were derived from VH1, VH3 and VH4, and both the IgM-positive (four cases) and IgG-positive (two cases) were extensively mutated from germline sequence. In two cases, early and late passage tumor cells were available, and the VH nucleotide sequences were identical, indicating that mutations had not accumulated in vitro. In a further case, there was evidence of sequence heterogeneity, which appeared to have been generated in vivo, indicating that the tumor cell VH gene was able to undergo posttranslocation somatic hypermutation. Analysis of the relatively nonpolymorphic VH4 genes for the pattern of replacement or silent mutations did not show a role for antigen selection in the expressed sequences. 相似文献
992.
J. Mattern M. Kaufmann M. Volm U. Schütze K. Wayss Kl. Goerttler C. Tasca 《Journal of molecular medicine (Berlin, Germany)》1972,50(4):196-198
Zusammenfassung Mit einer früher beschriebenen Methode zur Sensibilitätstestung (3H-Thymidineinbau, Flüssigkeitsscintillationsmessung) haben wir 30 menschliche Adenocarcinome (10 Rectum-Sigma-Carcinome, 10 Magen-Carcinome, 30 Mamma-Carcinome) gegenüber Trenimon®, Methotrexat® und Natulan® getestet und statistisch ausgewertet. Die in unserer früheren Untersuchung vermutete Individualität der Tumoren konnte bestätigt werden.Stipendiat der Alexander von Humboldt-Stiftung. 相似文献
993.
Abnormalities of taste and smell in Sjogren's syndrome 总被引:1,自引:0,他引:1
994.
995.
Longitudinal study of rotavirus infection in child-care centres 总被引:1,自引:0,他引:1
MJ FERSON S STRINGFELLOW K McPHIE CJ McIVER A SIMOS 《Journal of paediatrics and child health》1997,33(2):157-160
To describe the epidemiology of symptomatic and asymptomatic rotavirus infection among young children attending Sydney child-care centres during the 1994 rotavirus season.
Children aged 0–36 months in 11 child-care centres participated in the study. A weekly stool specimen was collected from each subject and tested for rotavirus antigen by commercial enzyme immunoassay.
One hundred and seventy-eight children (76 girls and 102 boys) with a mean age of 18.2 ± 6.5 (SD) months were enrolled for a total of 2249 child-weeks. Of 1653 weekly faecal specimens, 59 (3.6%) were positive for rotavirus antigen. Positivity for rotavirus antigen peaked at 8.0% and 7.4% of specimens in weeks 6 and 7, respectively. The 59 positive specimens were obtained from 44 children in eight of the 11 study centres. One child appeared to suffer a second episode. Eighty-two per cent of episodes were associated with symptoms of gastroenteritis. Overall, 32% of the children in the eight affected centres were infected; 52% of those <12 months were infected compared to 26% of older children. Secondary spread to household contacts was also documented.
Rotavirus infection poses a significant health problem in under-3-year-old children attending child-care centres in Sydney. We believe that these results are applicable to all Australian children of this age attending group child care. 相似文献
Methods:
Children aged 0–36 months in 11 child-care centres participated in the study. A weekly stool specimen was collected from each subject and tested for rotavirus antigen by commercial enzyme immunoassay.
Results:
One hundred and seventy-eight children (76 girls and 102 boys) with a mean age of 18.2 ± 6.5 (SD) months were enrolled for a total of 2249 child-weeks. Of 1653 weekly faecal specimens, 59 (3.6%) were positive for rotavirus antigen. Positivity for rotavirus antigen peaked at 8.0% and 7.4% of specimens in weeks 6 and 7, respectively. The 59 positive specimens were obtained from 44 children in eight of the 11 study centres. One child appeared to suffer a second episode. Eighty-two per cent of episodes were associated with symptoms of gastroenteritis. Overall, 32% of the children in the eight affected centres were infected; 52% of those <12 months were infected compared to 26% of older children. Secondary spread to household contacts was also documented.
Conclusions:
Rotavirus infection poses a significant health problem in under-3-year-old children attending child-care centres in Sydney. We believe that these results are applicable to all Australian children of this age attending group child care. 相似文献
996.
The intracellular distribution of adenosine 5'-triphosphate (ATP) and 2,3-diphosphoglycerate (2,3-DPG) was studied in the red cells of a patient with a "high-ATP syndrome" by using 31P nuclear magnetic resonance. In this patient, red cell ATP was increased 2.5-fold, whereas 2,3-DPG was decreased fourfold due to the presence of a hyperactive pyruvate kinase. In oxygenated red cells, these abnormal concentrations were reflected to the same extent in all complexes in which ATP and 2,3-DPG take part. The diminished amount of 2,3-DPG bound to hemoglobin was almost completely replaced by ATP-hemoglobin complexes. Therefore, free hemoglobin was only slightly increased. In deoxygenated cells, the relative distribution of ATP and 2,3-DPG complexes was significantly disturbed. The main difference was a shift in the ratio of magnesium ATP (MgATP) over the ATP-hemoglobin complex; 74% of total ATP was complexed to hemoglobin (45% in normal cells), whereas the concentration of MgATP was only slightly increased with respect to normal. The shortage in 2,3-DPG bound to hemoglobin could partially be replenished by an increase in hemoglobin (Mg) ATP complexes. Therefore, the amount of uncomplexed hemoglobin raised from 15% in normal cells to 38% in the patient's cells. As a result, the oxygen-dissociation curve was only moderately shifted to the left. It is concluded that the regulatory role of 2,3-DPG in oxygen transport is taken over in part by (Mg) ATP in this patient. In both aerobic and anaerobic cells, the increase in magnesium bound to ATP, either free or bound to hemoglobin, exceeds the decrease in 2,3-DPG Mg complex. In spite of this, the amount of intracellular free Mg++ was normal or slightly lowered. This suggests the presence of a compensatory mechanism by which the amount of total cellular magnesium could be increased. 相似文献
997.
Ninety-four human non-small cell lung carcinomas (NSCLC) of previously untreated patients were analyzed for the presence of metallothionein (MT) expression by means of immunohistochemistry. Of the tumors investigated, expression of MT was detected in 63%. The expression of MT was correlated with the results of doxorubicin resistance of the tumors in vitro. A significant relationship between MT expression and doxorubicin resistance was found (p=0.01). Significant correlations also exist between MT and P-glycoprotein or glutathione-S-transferase-pi expression respectively (p<0.005). 相似文献
998.
Only hydrosalpinges visible on ultrasound are associated with reduced implantation and pregnancy rates after in-vitro fertilization 总被引:3,自引:10,他引:3
de Wit W; Gowrising CJ; Kuik DJ; Lens JW; Schats R 《Human reproduction (Oxford, England)》1998,13(6):1696-1701
A retrospective analysis of clinical and laboratory data was made of all
in-vitro fertilization (IVF) patients with tubal pathology who had their
first ever embryo transfer cycle between January 1st, 1992 and September
1st, 1996. The aim of the study was to determine the effect of the presence
of a hydrosalpinx, whether or not visible by ultrasound, on pregnancy,
multiple pregnancy and implantation rates in our patient population. The
IVF success rate was also analysed by calculating cumulative ongoing
pregnancy rates of the same patient group using the lifetime table
approach. In the presence of an ultrasound-visible hydrosalpinx, rates of
pregnancy and multiple pregnancy appeared reduced, but the differences were
not significant. The rates of implantation, clinical implantation and
ongoing implantation were significantly lower in the presence of an
ultrasound- visible hydrosalpinx (odds ratios 0.33-0.46, C.I. 0.21-0.96).
The cumulative chance of achieving an ongoing pregnancy after one or more
IVF cycles was significantly reduced in the presence of an ultrasound-
visible hydrosalpinx (relative hazard 0.36, C.I. 0.22-0.59). In the
presence of a hydrosalpinx not visible by ultrasound the IVF outcome was
not reduced. This retrospective study confirms that patients with
hydrosalpinges have an impaired IVF outcome. Unique to this study and
previously unobserved is the finding that there is a subgroup of patients
with hydrosalpinges, those with ultrasound-visible hydrosalpinges, which is
exclusively responsible for this impaired outcome.
相似文献
999.
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
1000.
Warnich L; Kotze MJ; Groenewald IM; Groenewald JZ; van Brakel MG; van Heerden CJ; de Villiers JN; van de Ven WJ; Schoenmakers EF; Taketani S; Retief AE 《Human molecular genetics》1996,5(7):981-984
Mutation analysis of genomic DNA samples obtained from 17 unrelated South
African patients with variegate porphyria (VP) revealed three novel
missense mutations in the protoporphyrinogen oxidase (PPOX) gene. A common
C to T transition at nucleotide position 452 (R59W) was identified in 15 of
the patients analysed, while base changes at positions 336 (H20P) and 779
(R168C) were identified in the remaining two patients. Using protein
analysis software we were able to predict that all three mutations have a
similar biophysical effect on the protein, being the disturbance of
amphiphatic regions within the protein, which might result in misfolding of
the protein. Mutation R59W, identified in the majority of South African VP
families, was shown to create a Styl restriction site, while mutation R168C
would abolish a Dsal restriction site in genomic DNA of affected
individuals. As 100% of the index patients analysed were molecularly
characterized, the combined use of restriction enzyme and single-strand
conformation polymorphism (SSCP) analysis now allows a rapid and accurate
diagnosis of VP in South Africa. Mutation R59W was furthermore shown to be
in association with one of four potential haplotypes defined by two newly
described polymorphisms in exon 1 of the PPOX gene. Our molecular data thus
strongly support the founder hypothesis for VP in South Africa.
相似文献