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91.
Identification of the central vestibular projections in man: a positron emission tomography activation study 总被引:4,自引:0,他引:4
Gabriella Bottini Roberto Sterzi Eraldo Paulesu Giuseppe Vallar Stefano F. Cappa Francesco Erminio Richard E. Passingham Chris D. Frith Richard S. J. Frackowiak 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,99(1):164-169
The cerebral representation of space depends on the integration of many different sensory inputs. The vestibular system provides one such input and its dysfunction can cause profound spatial disorientation. Using positron emission tomography (PET), we measured regional cerebral perfusion with various vestibular stimulations to map central vestibular projections and to investigate the cerebral basis of spatial disorientation. We showed that the temporoparietal cortex, the insula, the putamen, and the anterior cingulate cortex are the cerebral projections of the vestibular system in man and that the spatial disorientation caused by unilateral vestibular stimulation is associated with their asymmetric activation. 相似文献
92.
Giuseppe Caliendo Ferdinando Fiorino Paolo Grieco Elisa Perissutti Vincenzo Santagada Rosaria Meli Giuseppina Mattace Raso Angelina Zanesco Gilberto De Nucci 《European journal of medicinal chemistry》1999,34(12):1043
Two sets of benzotriazinone and benzoyltriazole derivatives were prepared and tested for local anaesthetic activity in comparison with lidocaine. Several of the prepared compounds exhibited a fairly good activity comparable or superior to that of lidocaine. The presence of a benzotriazinone or a benzoyltriazole moiety as an aromatic system was quite profitable for both the intensity and duration of activity. The acute toxicity in mice of the four most potent compounds of the series was also assessed. Compound 1b, which has an anaesthetic activity comparable to that of lidocaine, was also characterized by a more favourable therapeutic index. All compounds were tested in vitro to evaluate their negative chronotropic action in isolated rat right atria. 相似文献
93.
Paolo Bongioanni Francesco Lombardo Cristina Fioretti Giuseppe Meucci 《Journal of neurology》1996,243(8):605-610
Multiple sclerosis (MS) is a T-cell-mediated autoimmune demyelinating disease of the central nervous system (CNS), associated with an altered immunoregulation. Interferon (IFN)-, also known as immune IFN, is a cytokine with several effects on the immune system. Specific IFN- receptors have been found on human lymphocytes, as well as on other cell types (e.g. gliocytes), even in the CNS. The aim of the present study was to evaluate IFN- binding on peripheral blood T-lymphocytes from MS patients, compared with those from healthy subjects. Thirty-two patients were selected according to the classical criteria for definite MS; as controls, 21 healthy subjects were studied. We have found that T-lymphocytes from MS patients bear a significantly smaller amount of IFN- receptors than those from controls [B
max: 568, 18 vs 708, 14 (mean, SE) receptors/cell]. Such IFN- binding sites are of the same type in patients and healthy subjects [K
d: 1.0, 0.05 vs 0.9, 0.02 (mean, SE) nM]. These findings are discussed in terms of immunopathogenesis of MS, since it has been reported that activated T-lymphocytes have decreased amounts of IFN- receptors. 相似文献
94.
E Riva R Latini A Cremonesi F Zacà P Pagliarani 《Journal of cardiovascular pharmacology》1980,2(6):707-714
We studied the time course of three electrophysiologic effects of propranolol after intravenous and oral administration and their relationship with plasma levels within the same subjects. Ten patients who had undergone cardiac catheterization for diagnostic purposes received 0.1 mg/kg of propranolol intravenously. Blood was drawn at intervals for 12 hr and heart rate and the effective refractory periods of the atrium (ERPA) and the atrioventricular node (ERPAVN) were determined at the same time. Eight patients continued treatment with propranolol by the oral route for up to 4 days (40 mg every 12 hr). Blood was sampled after each morning dose. Plasma concentrations of propranolol were measured by gas chromatography. Maximal lengthening of ERPA after propranolol (15.1% i.v. and 9.4% oral) was much less marked than that of ERPAVN (23.2% i.v. and 19.4% oral). Heart rate decreased 23.5% (i.v.) and 13.1% (oral). Effects were seen much sooner after intravenous (5-8 min) than after oral administration (86-146 min), but they lasted about twice as long after oral as after intravenous treatment. 相似文献
95.
96.
Carlo Orzincolo M.D. Pier Nuccio Scutellari M.D. Giuseppe Castaldi M.D. 《Skeletal radiology》1992,21(1):39-44
In 12 patients affected by thalassemia major who received an intensive transfusion regimen combined with continuous iron chelation therapy (desferrioxamine 50–80 mg/kg daily), radiologic abnormalities of the long bones were observed similar to those observed in rickets and scurvy. These abnormalities were associated with a growth retardation. The pathogenesis of these lesions is uncertain, but probably the toxic effect of desferrioxamine plays an important role in their development. A relative deficiency of vitamins D and/or C cannot be entirely excluded. 相似文献
97.
Alessandro Filla Giuseppe De Michele Francesca Cavalcanti Filippo Santorelli Lucio Santoro Giuseppe Campanella 《Journal of neurology》1991,238(3):147-150
Summary Three families are described which include members with typical Friedreich's disease (FD) and others who are ataxic but do not satisfy all the diagnostic criteria for that disease. In family A two patients have an early-onset, rapidly progressive FD, while two others have a late-onset, more benign form. In families B and C one member has typical FD, and another has a similar ataxic syndrome, except for preservation of knee jerks. Laboratory evaluation is consistent with the diagnosis of FD in all cases. FD diagnosis appears justified in secondary cases with late onset or preserved tendon reflexes, provided that the index case fulfils all diagnostic criteria. Whether the diagnosis of FD is tenable in sporadic atypical cases remains to be seen. Echocardiographic and neurophysiological examination may be valuable in classifying such cases. 相似文献
98.
The Authors compare the results obtained between two groups of patients suffering from leg lipodystrophy, who were subjected
to a reducing lipoplasty. In the first group, surgeons made use of a new sort of cannula, deprived of the classical grip,
whereas in the second group, they employed the traditional probe. The best results, achieved with the first group, prove this
new operating system is really effective, particularly on legs, for the following reasons:
(1) Higher precision and better control of the instrument
(2) Swan-neck cannula abolition
(3) Opportunity to operate with both hands
(4) Halved operating time
(5) No tiredness after the operation. 相似文献
99.
Francesco Izzo Paolo Marra Gerardo Beneduce Giuseppe Castello Paolo Vallone Vincenzo De Rosa Franco Cremona C Mark Ensor Frederick W Holtsberg John S Bomalaski Mike A Clark Chaan Ng Steven A Curley 《Journal of clinical oncology》2004,22(10):1815-1822
PURPOSE: Recently, we reported that a large number of human hepatocellular cancer (HCC) cell lines were auxotrophic for arginine. Here we report the results obtained with the amino acid-degrading enzyme arginine deiminase (ADI) conjugated to polyethylene glycol (ADI-SS PEG 20,000 mw) as a means of lowering plasma arginine to treat HCC. The study was a cohort dose-escalation phase I/II study. PATIENTS AND METHODS: Pharmacodynamic studies indicated an ADI-SS PEG 20,000 mw dose level of 160 U/m(2) was sufficient to lower plasma arginine from a resting level of approximately 130 micromol/L to below the level of detection (< 2 micromol/L) for more than 7 days, a dose later defined as the optimal biologic dose. All patients were to receive three cycles at the optimum biologic dose. RESULTS: This therapy was well tolerated, even in patients who had no detectable plasma arginine for 3 continuous months of therapy. Of the 19 patients enrolled, two had a complete response, seven had a partial response, seven had stable disease, and three had progressive disease. The median survival for the 19 patients enrolled on this study was 410 days, with four patients still alive at present (> 680 days). CONCLUSION: Elimination of all detectable plasma arginine in patients with HCC was well tolerated and seemed to be effective in the treatment of some patients with HCC. Further testing of ADI-SS PEG 20,000 mw in a larger population of individuals with HCC as well as other human tumors auxotrophic for arginine is warranted. 相似文献