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181.
Buschard K Bock T Pedersen CR Hansen SV Aaen K Jørgensen M Hansen MW Kjaer TW Hageman I Josefsen K 《International journal of experimental diabetes research》2000,1(1):1-8
The aim of the study was to investigate whether various beta-cell stimulatory drugs, given neonatally, influence the incidence of diabetes in BB rats. Newborn BB rats were treated twice daily for 6 days and diabetes development was observed during the following 200-day study period. Compared to a diabetes incidence of 63.8% in 163 control BB rats which received saline or were untreated, the percentage of experimental BB rats that developed diabetes was as follows in the different subgroups: arginine-glucose: 47% (n = 73, p < 0.02); glucagon: 37% (n = 93, p < 0.0001); tolbutamide-glucose: 36% (n = 58, p < 0.0005); and theophylline-glucose: 39% (n = 41, p < 0.005). A long-term arginine-glucose treatment was not superior to the shorter neonatal treatment. Histological examination revealed a higher degree of insulitis in diabetic than in non-diabetic animals but no difference according to the kind of treatment was observed. Finally, we found that the diabetes incidence in BB rats was higher in the first litter compared to subsequent litters (p = 0.04). Thus, neonatal treatment with various beta-cell stimulatory agents reduces diabetes incidence in BB rats. The theory behind the study, that the treatment accelerates beta-cell maturation leading to increased immunological tolerance towards beta cells, is discussed. 相似文献
182.
Dr. F. Schmidt H. Nietsch K. Krieger H. Frimmel C. Bock C. Kunze U. Preiß 《Monatsschrift für Kinderheilkunde》2007,155(11):1015-1016
Ohne Zusammenfassung 相似文献
183.
Moormann AM Sullivan AD Rochford RA Chensue SW Bock PJ Nyirenda T Meshnick SR 《The Journal of infectious diseases》1999,180(6):1987-1993
Malaria infections during pregnancy can lead to the delivery of low-birth-weight infants. In this study, cytokine mRNA was measured in placentas from 23 malaria-infected and 21 uninfected primigravid women who had delivered in Mangochi, Malawi, a region with a high rate of transmission of falciparum malaria. Significantly increased expression of interleukin (IL)-1beta, IL-8, and tumor necrosis factor (TNF)-alpha and decreased expression of IL-6 and transforming growth factor-beta1 were found in malaria-infected compared with uninfected placentas. TNF-alpha and IL-8 were produced by maternally derived hemozoin-laden placental macrophages. Increased TNF-alpha expression was associated with increased placental hemozoin concentrations. Increased TNF-alpha or IL-8 expression in the placenta was associated with intrauterine growth retardation but not with preterm delivery. The results suggest that malaria infections induce a potentially harmful proinflammatory response in the placenta. 相似文献
184.
Pinto BM Borrelli B King TK Bock BC Clark MM Roberts M Marcus BH 《Addictive behaviors》1999,24(1):75-86
This study examined characteristics associated with weight control smoking among 281 sedentary women enrolled in a smoking cessation trial. A series of regression models were developed to identify predictors of weight control smoking as measured by the Smoking Situations Questionnaire. Predictor variables included demographic variables, dietary intake, weight gain following previous quit attempts, dietary restraint, self-efficacy for weight management, smoking behavior, exercise behavior, negative affect and psychological constructs relevant to smoking cessation, and exercise adoption. In the final predictor model, anticipation of weight gain in the current quit attempt, higher dietary restraint, younger age, greater Fagerstrom scores, greater number of pounds gained in previous quit attempts, and lower levels of self-efficacy to manage weight in negative affect situations were associated with smoking for weight control. Treatment implications for women who smoke for weight control reasons are discussed. 相似文献
185.
Rybicki BA Maliarik MJ Bock CH Elston RC Baughman RP Kimani AP Sheffer RG Chen KM Major M Popovich J Iannuzzi MC 《Sarcoidosis, vasculitis, and diffuse lung diseases : official journal of WASOG / World Association of Sarcoidosis and Other Granulomatous Disorders》1999,16(2):203-208
BACKGROUND: A genetic predisposition to sarcoidosis has long been postulated, although no specific susceptibility genes are known. Candidate genes for the two granulomatous inflammatory disorders with clinical similarities to sarcoidosis, Blau syndrome and Crohn's disease, have been localized to a 40 centimorgan region spanning the chromosome 16 centromere. PATIENTS AND METHODS: Using a sample of 35 African-American sibling pairs, who both had clinically confirmed sarcoidosis, we tested for genetic linkage between the 16p12-q21 interval (the likely location of the Blau syndrome gene) and sarcoidosis. RESULTS: We found no evidence for linkage to any of the eight markers we tested in the 16p12-q21 interval. Ninety percent of the 16p12-q21 region had a LOD score < -2 for a dominant gene conferring a relative risk of 3 or greater for sarcoidosis. One hundred percent of the region had a LOD score < -2 for a dominant gene with a relative risk of 3.5 or greater or recessive gene with relative risk of 2.5 or greater. Based on simulation results we could not exclude a dominant gene with relative risk < 5 at the 0.05 significance level, nor a recessive gene with relative risk < 3, over the entire 16p12-q21 interval. CONCLUSIONS: While the clinical similarities between Blau Syndrome and sarcoidosis suggest genetic homogeneity between the disorders, we found no evidence for linkage of sarcoidosis to the Blau syndrome locus. Our exclusion results suggest that the Blau Syndrome gene does not have a major effect on sarcoidosis susceptibility. 相似文献
186.
187.
The positive evidence of the caloric test increases, when the time-course of the induced heat wave in the petrous bone was eliminated, which differs from man to man. This is possible by changing head position during calorisation, so that a nearly rectangular stimulus results. 相似文献
188.
189.
Fakkert IE Jansen L Meijer K Kok T Oosterwijk JC Mourits MJ de Bock GH 《Breast cancer research and treatment》2011,129(1):157-164
Breast cancer screening is offered to BRCA1 and BRCA2 mutation carriers from the age of 25 years because of their increased risk of breast cancer. As ovarian cancer screening
is not effective, risk-reducing salpingho-oophorectomy (RRSO) is offered after child bearing age. RRSO before menopause reduces
the breast cancer risk as well as breast density. It can be questioned whether after premenopausal RRSO, the intensive breast
cancer screening program needs modification. We evaluated the effectiveness of breast cancer screening by clinical breast
examination (CBE), mammography, and MRI in a population of 88 BRCA1 and 51 BRCA2 mutation carriers who had RRSO before the age of 52. Sensitivity, specificity, positive predictive value (PPV), and negative
predictive value (NPV) were calculated for each screening modality. During 422 women years, 14 breast cancers were diagnosed;
2 prevalent, 10 screen detected and 2 interval breast cancers (12 in BRCA1 and 2 in BRCA2 mutation carriers). Sensitivity, specificity, PPV, and NPV for the combined screening were 85.7%, 97.6%, 30.0%, and 99.8%,
respectively. No tumors were found with CBE, MRI had a sensitivity of 60.0% and mammography of 55.6%. Off all the tumors,
60% were node positive. Effectiveness of CBE and mammography was comparable to earlier findings. MRI screening seemed less
effective than earlier findings. After RRSO, the breast cancer risk in BRCA1 and BRCA2 mutation carriers is still high enough to justify intensive breast cancer screening with MRI and mammography. 相似文献
190.
D. Linnemann H. Gaardsvoll M. Olsen E. Bock 《International journal of developmental neuroscience》1993,11(1)
In aging brain, degenerative as well as compensatory regenerative processes are believed to occur. The neural cell adhesion molecule NCAM is involved in developmental and regenerative processes in the brain. However, the role of NCAM in aging brain has not been characterized. In this study, the expression of NCAM mRNAs and polypeptides was investigated in aging rat brain. The 7.4 and 6.7 kb NCAM mRNAs were selectively downregulated during postnatal development, and the 5.2 and 2.9 kb NCAM mRNAs were upregulated. However, from postnatal day 40 to old age no change in NCAM mRNA classes was observed. The fraction of NCAM mRNA containing the VASE exon increased postnatally but remained stable during adult life. VASE, which is believed to modulate the binding capacity, seemed to be relatively more abundant in the 7.4 and 6.7 kb NCAM mRNAs, encoding transmembrane NCAM forms, than in the 5.2 and 2.9 kb NCAM mRNAs, coding for glycosyl phosphatidylinositol (GPI) linked NCAM. Conversely, insertion of exons a and AAG between exons 12 and 13, a region containing two fibronectin type III repeats, seemed to be more pronounced in 5.2 and 2.9 kb NCAM mRNAs than in the 7.4 and 6.7 kb mRNAs. During postnatal development an increase in the fraction of 6.7 kb NCAM mRNA containing the exons a and AAG was observed. However, during aging the fraction of NCAM mRNAs containing this exon combination seemed constant. At the protein level, NCAM-A was downregulated both during development and aging. No changes were observed during aging in the composition of soluble NCAM forms in the brain, cerebrospinal fluid or blood plasma. The amount of NCAM in rat brain decreased during postnatal development, but remained at a constant level from postnatal day 40 to old age.To conclude, several changes in NCAM expression occur during early postnatal development emphasizing the important role of this molecule in the morphogenetic processes. During aging, a significant selective downregulation of NCAM-A was observed indicating that in general only minor regenerative processes occur in the brain. 相似文献