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91.
This paper uses a full-information maximum likelihood estimation procedure, the Discrete Factor Method, to estimate the relationship between birthweight and prenatal care. This technique controls for the potential biases surrounding both the sample selection of the pregnancy-resolution decision and the endogeneity of prenatal care. In addition, we use the actual number of prenatal care visits; other studies have normally measured prenatal care as the month care is initiated. We estimate a birthweight production function using 1993 data from the US state of Texas. The results underscore the importance of correcting for estimation problems. Specifically, a model that does not control for sample selection and endogeneity overestimates the benefit of an additional visit for women who have relatively few visits. This overestimation may indicate 'positive fetal selection,' i.e., women who did not abort may have healthier babies. Also, a model that does not control for self-selection and endogenity predicts that past 17 visits, an additional visit leads to lower birthweight, while a model that corrects for these estimation problems predicts a positive effect for additional visits. This result shows the effect of mothers with less healthy fetuses making more prenatal care visits, known as 'adverse selection' in prenatal care. 相似文献
92.
Newton-Bishop JA Nolan C Turner F McCabe M Boxer C Thomas JM Coombes G A'Hern RP Barrett JH 《The journal of investigative dermatology. Symposium proceedings / the Society for Investigative Dermatology, Inc. [and] European Society for Dermatological Research》2004,9(2):152-159
A quality-of-life study was carried out to test the hypothesis that melanoma patients treated with a 3-cm margin of excision suffer greater impairment of their quality of life than those treated with a 1-cm margin. The secondary aim was to determine the predictors of a poor patient perception of their excision scar. A postal questionnaire study was carried out using Hospital Anxiety and Depression (HAD), Psychosocial Adjustment of Illness Scale-Self-Report (PAIS-SR), Medical Outcomes Survey-Short Form 36 (MOS-SF36), and the Cassileth Scar questionnaires. Data were collected from 426 of the 537 patients who were mailed the questionnaires (response rate 79%). Fourteen percent had clinically significant anxiety and 5% had significant depression. A poor attitude toward quality of health care was associated with youth. Patients treated with a 3-cm margin excision had significantly poorer mental and physical function 1 mo after surgery, which disappeared within 6 mo. The greater difficulties experienced by the 3-cm margin group were particularly in their domestic, sexual, and social roles. Women, younger patients, those with poor physical and mental function after surgery, and those treated by a 3-cm margin were more likely to report a poorer perception of their scar. The poorer scar perception of patients in the 3-cm group persisted throughout the study period. Use of a 3-cm margin of excision for melanoma is associated with significantly more morbidity than use of a 1-cm margin, but this effect disappears in 6 mo. Patients treated by 3-cm excision were more likely, however, to have a persistent poor view of their scar. Youth and being female were also predictors of poor perception of the scar. 相似文献
93.
HPLC-based activity profiling of Salvia miltiorrhiza for MAO A and iNOS inhibitory activities 总被引:2,自引:0,他引:2
In the course of a screening of plant extracts for potential CNS and anti-inflammatory activities, a dichloromethane extract of Salvia miltiorrhiza showed a pronounced inhibitory effect on recombinant monoamine oxidase A (MAO A) and on inducible NO synthase (iNOS) induction in Raw 267.4 cells. With the aid of HPLC-based profiling techniques, activities could be linked, to a significant extent, to peaks of tanshinone-type diterpenoids, four of which were subsequently isolated. The IC50 of the most active compound, 15,16-dihydrotanshinone I, on human recombinant MAO A was at 23 microM, and 2.4 microM on lipopolysaccharide-mediated iNOS induction in Raw 267.4 cells. 相似文献
94.
Newcomb E. W. Bhalla Sandhya K. Parrish Clarissa L. Hayes Roberta L. Cohen Henry Miller Douglas C. 《Acta neuropathologica》1997,94(4):369-375
bcl-2 protein expression was characterized in a series of 58 astrocytomas from 21 pediatric and 37 adult patients. As part
of a continuing attempt to define relevant prognostic factors which may predict clinical outcome, we have determined the impact
of bcl-2 accumulation in malignant astrocytes on the length of patient survival. Aberrant overexpression of bcl-2 protein
in tumor cells was detected in 57% (12 of 21) of pediatric and 73% (27 of 37) of the adult cases. Among pediatric patients,
the median survival in months showed no relationship with the incidence of bcl-2-positive tumors. Among the adult patients,
a favorable prognostic indicator was low-tumor grade (P = 0.05). bcl-2-positive tumors occurred with similar frequencies in WHO grades III and IV of malignancy. When bcl-2 expression
in tumor cells was tested as a variable to predict for patient survival, the 6 patients without bcl-2 expression among 23
adult patients with grade IV tumors had a shorter median survival. The same 58 tumors had been previously analyzed for alterations of p53: 4 pediatric and 16 adult tumors had p53 gene mutations. There was no significant difference in median survival related to p53 gene status. There was no relationship between bcl-2 expression and p53 gene status: approximately equal numbers of tumors with either wild-type or mutant p53 were bcl-2 negative or bcl-2 positive.
bcl-2 expression is high (40–100%) among other tumors of the central nervous system which also show low malignant potential.
Up-regulation of bcl-2 in malignant astrocytes or constitutive expression in some tumor types may be a factor leading to a
more favorable clinical outcome.
Received: 27 January 1997 / Revised: 21 March 1997 / Accepted: 28 March 1997 相似文献
95.
Fred Frankel Robert Myatt Catherine Sugar Cynthia Whitham Clarissa M. Gorospe Elizabeth Laugeson 《Journal of autism and developmental disorders》2010,40(7):827-842
This study evaluated Children’s Friendship Training (CFT), a manualized parent-assisted intervention to improve social skills
among second to fifth grade children with autism spectrum disorders. Comparison was made with a delayed treatment control
group (DTC). Targeted skills included conversational skills, peer entry skills, developing friendship networks, good sportsmanship,
good host behavior during play dates, and handling teasing. At post-testing, the CFT group was superior to the DTC group on
parent measures of social skill and play date behavior, and child measures of popularity and loneliness, At 3-month follow-up,
parent measures showed significant improvement from baseline. Post-hoc analysis indicated more than 87% of children receiving
CFT showed reliable change on at least one measure at post-test and 66.7% after 3 months follow-up. 相似文献
96.
The fatty acid-binding protein-2 A54T polymorphism is associated with renal disease in patients with type 2 diabetes 总被引:1,自引:0,他引:1
Canani LH Capp C Ng DP Choo SG Maia AL Nabinger GB Santos K Crispim D Roisemberg I Krolewski AS Gross JL 《Diabetes》2005,54(11):3326-3330
The intestinal fatty-acid binding protein-2 (FABP2) gene codes a protein responsible for the absorption of long-chain fatty acids. To test whether FABP2 is a candidate gene for renal disease in patients with type 2 diabetes, a functional A54T polymorphism was genotyped in 1,042 Brazilians with type 2 diabetes. Patients were classified as having normoalbuminuria (urinary albumin excretion [UAE] <20 microg/min; n = 529), microalbuminuria (UAE 20-199 microg/min; n = 217), or proteinuria (UAE >199 microg/min; n = 160). Patients with end-stage renal disease (ESRD) (n = 136) were also included. The prevalence of the TT genotype was higher in patients with renal involvement compared with those with normoalbuminuria (odds ratio [95% CI] 2.4 [1.1-5.4]) following adjustment for type 2 diabetes duration, BMI, hypertension, A1C, and cholesterol levels. The risk was similar considering different stages of renal involvement. In a second independent patient sample (483 type 2 diabetic Caucasians residing in Massachusetts), a significant association was also observed between the TT genotype and proteinuria or ESRD (2.7 [1.0-7.3]; P = 0.048). This study thus provides evidence that FABP2 confers susceptibility to renal disease in type 2 diabetic patients. 相似文献
97.
Ceramide induces mitochondrial activation and apoptosis via a Bax-dependent pathway in human carcinoma cells 总被引:8,自引:0,他引:8
von Haefen C Wieder T Gillissen B Stärck L Graupner V Dörken B Daniel PT 《Oncogene》2002,21(25):4009-4019
The intracellular pathways leading to mitochondrial activation and subsequent cell death in the ceramide-mediated stress response have been intensively studied in recent years. Experimental evidence has been provided that ceramide-induced apoptosis is inhibited by overexpression of antiapoptotic proteins of the Bcl-2 family. However, the direct effect of proapoptotic gene products, e.g. Bax, on ceramide-induced death signalling has not yet been studied in detail. In the present work, we show by measurement of mitochondrial permeability transition, cytochrome c release, activation of caspase-3 and DNA fragmentation that ceramide-induced apoptosis is marginal in Bax-negative DU 145 cells. Reconstitution of Bax by generation of DU 145 cells stably expressing this proapoptotic factor, clearly enhanced ceramide-induced apoptosis at all levels of the mitochondrial signalling cascade. Using the broad-range caspase inhibitor zVAD-fmk and zDEVD-fmk, an inhibitor of caspase-3-like activities, we demonstrate that the ceramide-induced mitochondrial activation in Bax-transfected DU 145 cells is caspase-independent. On the other hand, apoptotic events located downstream of the mitochondria, e.g. DNA fragmentation, were shown to be caspase-dependent. This influence of Bax on ceramide-induced apoptosis was confirmed in another cellular system: whereas Bax-positive HCT116 wild type cells were very sensitive towards induction of cell death by C(2)-ceramide, sensitivity of Bax knock-out HCT116 cells was significantly reduced. Thus, we conclude that Bax is a key activator of ceramide-mediated death pathways. 相似文献
98.
99.
100.
Peyton Rous 《The Journal of experimental medicine》1925,41(6):739-759
In continuation of the observations on vital staining by means of phthalein indicators, reported in a previous paper, some members of the group with acid ranges have been employed. The results accord closely with those already obtained, in pointing to the existence of characteristic differences in the reaction within the organs. Roughly speaking, these latter fall into two groups. Within the members of the one a noteworthy acidity would appear to prevail, whereas in those of the other acidity seems slight at most, and in a few instances signs of a faint alkalinity are to be met. In general the "acid" organs are such as have a great metabolic activity whereas the "neutral" group manifest but an inconsiderable one. All of the tissues examined seem to be relatively acid compared with the blood plasma. The findings with the phthaleins as a group are discussed. 相似文献