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排序方式: 共有735条查询结果,搜索用时 15 毫秒
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Golli M; Van Nhieu JT; Mathieu D; Zafrani ES; Cherqui D; Dhumeaux D; Vasile N; Rahmouni A 《Radiology》1994,190(3):741
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Effects of race and socioeconomic status on survival of 1,332 black, hispanic, and white women with breast cancer 总被引:3,自引:0,他引:3
Dr. Luisa Franzini PhD Anna Fay Williams PhD Jack Franklin PhD S. Eva Singletary MD Richard L. Theriault DO 《Annals of surgical oncology》1997,4(2):111-118
Background: A survival disadvantage for black women with brest cancer, which persists after controlling for stage of the disease, has been reported. This study investigates the effects of race and socioeconomic status (SES) on breast cancer survival after controlling for age, stage, histology, and type of treatment.
Methods: Kaplan-Meier and Cox proportional hazards models were used to analyze the interaction between race and SES in predicting survival in a sample of 163 black, 205 Hispanic, and 964 white women with breast cancer treated at M. D. Anderson Cancer Center (1987–1991).
Results: The results of univariate and multivariate analyses indicate that race was not a significant predictor of survival after adjusting for SES and other confounding factors such as demographic and disease characteristics. SES remained a significant predictor of survival after all adjustments were made. There was no evidence of differences in type of treatment by race or SES if adjustments were made for stage.
Conclusions: These results suggest that institutional factors, such as access to treatment, do not explain survival differences by race or SES. Other factors associated with low SES, such as life-style and behavior, may affect survival. 相似文献
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A review was conducted of 264 consecutive patients who underwent surgical treatment for nodal metastases of the groin area from a primary melanoma of the lower extremity. We found no significant difference in survival or regional control created by the extent of node dissection performed, whether or not surgical treatment was a superficial femoral (n = 133) or an iliac and femoral node dissection (n = 131). We also determined that the age and sex of the patient, the location of the primary melanoma and the time that elapsed before the development of nodal metastases were not significant factors. However, the extent of tumor burden (the number of positive nodes and presence of extranodal disease) was useful in predicting patient survival and subsequent nodal basin relapse. Future improvement in survival rates will require effective systemic regimens rather than radical surgical treatment alone. 相似文献
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Inhibition of 2-nitropropane-induced rat liver DNA and RNA damage by benzyl selenocyanate 总被引:5,自引:2,他引:3
We observed that pretreatment of male F344 rats with benzyl selenocyanate,
a versatile organoselenium chemopreventive agent in several animal model
systems, decreases the levels of DNA and RNA modifications produced in the
liver by the hepatocarcinogen 2- nitropropane. To clarify the mechanisms
involved, we pretreated male F344 rats with either benzyl selenocyanate,
its sulfur analog benzyl thiocyanate, phenobarbital or cobalt
protoporphyrin IX; the latter is a depletor of P450. We then determined (1)
the ability of liver microsomes to denitrify 2-nitropropane, (2) effects on
2-nitropropane- induced liver DNA and RNA modifications and (3) amount of
nitrate excreted in rat urine following administration of the carcinogen.
Pretreatment with benzyl selenocyanate or phenobarbital increased the
denitrification activity of liver microsomes by 217 and 765%, respectively,
increased liver P4502B1 by 31- and 435-fold, respectively, decreased the
levels of 2-nitropropane-induced modifications in liver DNA (29-70% and
17-30%, respectively) and RNA (67-85% and 30-50%, respectively), and
increased the 24-h urinary excretion of nitrate by 157 and 209%,
respectively. Pretreatment with benzyl thiocyanate had no significant
effect on any of these parameters. Pretreatment with cobalt protoporphyrin
IX decreased liver P4502B 1 by 87%, decreased the denitrification activity
of liver microsomes by 76%, decreased the 24 h urinary excretion of nitrate
by 88.5%, but increased the extent of 2-nitropropane-induced liver nucleic
acid modifications by 17-67%. These results indicate that the metabolic
sequence from 2-nitropropane to the reactive species causing DNA and RNA
modifications does not involve the removal of the nitro group. Moreover,
they suggest that benzyl selenocyanate inhibits 2-NP-induced liver nucleic
acid modifications in part by increasing its detoxication through induction
of denitrification, although it is evident that other mechanisms must also
be involved.
相似文献
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In vitro thermo-chemosensitivity screening of spontaneous human tumors: significant potentiation for cisplatin but not adriamycin 总被引:2,自引:0,他引:2
A Calabro S E Singletary S Tucker A Boddie G Spitzer R Cavaliere 《International journal of cancer. Journal international du cancer》1989,43(3):385-390
The in vitro thermal enhancement of Adriamycin (ADR) and Cisplatin (CDDP) was investigated in 18 surgical biopsy specimens of human tumors cultured in the Adhesive Tumor Cell Culture System. Experimental conditions were adopted to simulate "therapeutic" trials: (a) temperature of 37.0 degrees C, 40.5 degrees C or 42.5 degrees C; (b) hyperthermic duration of 30, 60, or 120 min; and (c) 4-dose drug range normalized to human bone marrow toxicity. Drug concentrations that inhibited 90% of tumor growth (IC90) at 37.0 degrees C were compared to the IC90 at 40.5 degrees C and 42.5 degrees C, adjusted for the effect of heat alone. CDDP plus heat was a better combination than ADR plus heat, regardless of the temperature and the exposure duration: significant synergism (p less than 0.001) occurred in 37% of heat-CDDP combinations, as compared with 15% of heat-ADR combinations, and antagonism was significantly lower (p less than 0.001) for heat-CDDP than for heat-ADR (4.4% versus 21% of combinations, respectively). Within the CDDP group, higher temperature and longer heat exposure resulted in an increased incidence of chemosensitivity. No specific pattern of synergism was evident within the ADR group, but a trend toward a higher incidence of antagonistic effects with increasing hyperthermic duration was observed. 相似文献
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