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51.
Effect of cyclosporin A and analogues on cytosolic calcium and vasoconstriction: possible lack of relationship to immunosuppressive activity. 总被引:1,自引:1,他引:0
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A. Lo Russo A. C. Passaquin P. Andr M. Skutella U. T. Rüegg 《British journal of pharmacology》1996,118(4):885-892
1. The full therapeutic potential of the main immunosuppressive drug, cyclosporin A (CsA), is limited because of its side effects, namely nephrotoxicity and hypertension. Several lines of evidence suggest that the origin of both side effects could be CsA-induced vasoconstriction. However, the underlying molecular mechanisms are not well understood. 2. Diameter measurements of rat isolated mesenteric arteries showed an increase in noradrenaline- and [Arg]8vasopressin-induced vasoconstriction when arteries were pretreated with CsA. 3. Measurements in cultured vascular smooth muscle cells (VSMC) of either cytosolic calcium concentration or of 45Ca2+ efflux showed that CsA potentiated the calcium influx to several vasoconstrictor hormones: [Arg]8vasopressin, angiotensin II, endothelin-1 and 5-hydroxytryptamine. On the other hand, 45Ca2+ efflux in response to thapsigargin, which depletes calcium from intracellular pools, was not potentiated by CsA. 45Ca2+ uptake was not altered by CsA or by any of the analogues tested. 4. Time-course studies in cultured VSMC showed that maximal CsA-induced Ca2+ potentiation occurred after ca. 20 h and this effect was reversed over approximately the next 20 h. 5. To investigate the possible role played by the known intracellular targets of CsA, namely cyclophilin and calcineurin, CsA derivatives with variable potencies with respect to their immunosuppressive activity, were tested on the calcium influx to [Arg]8vasopressin. Derivatives devoid of immunosuppressive activity (cyclosporin H, PSC-833) potentiated calcium signalling, while the potent immunosuppressant, FK520, a close derivative of FK506, and MeVal4CsA, an antagonist of the immunosuppressive effect of CsA did not. The latter compound was unable to reverse the calcium potentiating effect of CsA. 6. Our results show that CsA increases the calcium influx to vasoconstrictor hormones in smooth muscle cells, which presumably increases vasoconstriction. Loading of the intracellular calcium pools appears not to be involved. Experiments with derivatives of CsA and FK520 suggest that interactions with cyclophilins and calcineurin are not the mechanism involved. This indicates, for the first time, that the immunosuppressive activity can be dissociated from the calcium potentiating effect of CsA in vascular smooth muscle. 相似文献
52.
53.
Functional decline in frail community-dwelling stroke patients 总被引:1,自引:0,他引:1
F. Landi G. Onder M. Cesari V. Zamboni A. Russo C. Barillaro R. Bernabei 《European journal of neurology》2006,13(1):17-23
Patients who suffer a stroke event are at high risk of functional decline after the post-acute rehabilitation period. The aim of the present study was the evaluation of factors associated with functional decline in a large sample of older patients with stroke living in the community. The study population consisted of all patients admitted to home care programs after a post-acute rehabilitation program--with at least 1 year of follow-up--in twenty-two Italian Home Health Agencies from 2000 to 2002 (n=1338). For the present study we selected 355 (26%) patients with diagnosis of stroke. After 1 year of in-home care program, 149 out of 355 stroke survivors (42%) had presented a worsening in the activities of daily living (ADL) scale score. In the final adjusted model, patients with cognitive impairment (OR 2.59, 95% CI, 1.45-4.64), pressure ulcer (OR 2.74, 95% CI, 1.45-5.18), urinary incontinence (OR 1.64, 95% CI, 1.01-3.29), or hearing impairment (OR 1.83, 95% CI, 1.02-3.29) were more likely to significantly decline in physical functioning after a period of 1 year in-home care program. Our study documents that functional decline of stroke patients was largely dependent on specific subjects' clinical characteristics. Three of four concomitant disabling conditions associated in our sample with functional decline--pressure ulcer, urinary incontinence, hearing--can be prevented and eventually treated or modified. Appropriate post-acute rehabilitation programs and adequate home care interventions focused on the prevention and treatment of these conditions might be correlated to better outcomes in older post-stroke patients. 相似文献
54.
M. Riva A. Salmaggi E. Marchioni A. Silvani G. Tomei L. Lorusso R. Merli F. Imbesi A. Russo 《Neurological sciences》2006,27(5):345-351
Abstract Epilepsy in high-grade glioma patients is a major concern, mainly as regards indications to treatment and best choice; toxicities,
and pharmocokinetic and pharmacodynamic interactions of drugs. All these generally unsolved problems complicate patients’
quality of life and interfere with the evaluation of response criteria in clinical trials. A prospective, multicentre data
collection on 132 adult newly diagnosed, histologically proven glioblastomas from 9 Lombardy hospitals collected in the same
database during a one-year period was recently published. From this database we report epidemiological and clinical characteristics
in epilepsy-symptomatic (31%) glioblastoma patients vs. the group with other presenting symptoms (69%). We analyse demographic
and clinico-radiological features, timing of onset and the course of seizures, and modalities of treatment in the two groups
of patients. No statistically significant differences were observed between the two groups as regards age, site of lesion(s),
extent of surgery and survival in relation to anticonvulsant treatment status or pharmacokinetic properties of drugs. 相似文献
55.
56.
Mutated c-Ha-ras oncogene alters cytokeratin expression in the human breast epithelial cell line MCF-10A.
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T. M. Paine G. Fontanini F. Basolo I. Geronimo J. W. Elliott J. Russo 《The American journal of pathology》1992,140(6):1483-1488
MCF-10A, a spontaneously immortalized human breast epithelial cell line, has been transformed by transfection with the mutated c-Ha-ras oncogene obtained from T24 carcinoma cells. The pattern of cytokeratin expression was studied in MCF-10A cells in comparison with plasmid transfected or MCF-10Aneo cells, normal ras proto oncogene transfected or MCF-10AneoN cells, and transformed or MCF-10AneoT cells. Cytokeratin expression was studied by western immunoblot of total cellular proteins separated by two-dimensional gel electrophoresis. Blots with cytokeratin specific AE1 and AE3 antibodies showed identical molecular weight species of cytokeratins in MCF-10A, MCF-10Aneo, MCF-10AneoN, and MCF-10AneoT cells; however, in MCF-10AneoT cells, the intensity of immunostaining and the number of immunoreactive phosphorylated polypeptides keratins 7, 8, 15, and 16 was decreased. It was concluded that c-Ha-ras oncogene-induced transformation alters quantitatively the cytokeratin pattern of human breast epithelial cells and that these changes could explain some of the morphologic alterations observed in c-Ha-ras transformed cells. 相似文献
57.
58.
T. Stroffolini G. Manzillo R. De Sena E. Manzillo P. Pagliano M. Zaccarelli M. Russo M. Soscia G. Giusti 《European journal of epidemiology》1992,8(4):539-542
Typhoid fever is endemic in the Neapolitan area, where its yearly incidence rate largely exceeds the corresponding national figure. During the period from January to June, 1990, a matched case-control study was carried out in order to identify risk factors of the disease in this area; 51 subjects (mean age 27.2 years) with typhoid fever were compared with 102 controls matched with respect to age, sex and educational level. Consumption of raw shellfish was reported by 76.5% of the cases, as opposed to 19.6% of the controls (P < 0.01). Subjects who had eaten this food item had a 13.3-fold risk (C.I. 95% = 5.5 - 32.8) of contracting typhoid fever. In contrast, no risk was found to be associated with consumption of cooked shellfish, raw vegetables, ice-cream, non-potable water, or unpasteurized milk.The risk factor identified in this study shows that hazardous dietary habits and inadequate sewage treatment facilities, combined with lack of sanitation in the harvesting and marketing of shellfish, play a major role in the endemicity of typhoid fever in the Neapolitan area.Corresponding author. 相似文献
59.
The Authors briefly summarise their experience of using various types of mechanical staplers in abdominal and thoracic surgery with excellent results both in general and in terms of reducing operating times. 相似文献
60.
E. S. Dellon J. A. Galanko R. K. Medapalli M. W. Russo 《American journal of transplantation》2006,6(9):2183-2190
Because creatinine is heavily weighed in the MELD (model for end-stage liver disease) score, we sought to determine the impact of MELD-based organ allocation on outcomes after transplantation in the pre- and post-MELD eras, focusing on recipients over age 65 on dialysis prior to transplant. A total of 20 196 patients from the UNOS database were analyzed. Comparing the pre-MELD to MELD era, there was a 41% increase in patients on dialysis (p<0.0001), and a 117% increase in combined liver/kidney transplants (p<0.0001). In the pre-MELD era, 1-year patient survival in recipients greater and less than age 65 on dialysis who received liver transplant alone was 56.8% and 76.4%, respectively (p=0.13). In the MELD era these rates were 50.7% and 77.8% (p=0.04). In the pre-MELD era, 1-year patient survival in recipients greater and less than age 65 on dialysis who underwent combined liver/kidney transplantation was 25.0% and 83.2%, respectively (p=0.0002). In the MELD era, these rates were 67.0% and 82.5% (p=0.18). In conclusion, a greater proportion of patients in the MELD era are on dialysis prior to transplant, and more receive combined liver/kidney transplants compared with the pre-MELD era. Candidates over age 65 who are on dialysis at the time of transplant have decreased survival after isolated liver transplantation. 相似文献