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31.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
32.
Urodilatin: a new peptide with beneficial effects in the postoperative therapy of cardiac transplant recipients 总被引:1,自引:0,他引:1
M. Hummel M. Kuhn A. Bub H. Bittner D. Kleefeld P. Marxen B. Schneider R. Hetzer W. G. Forssmann 《Journal of molecular medicine (Berlin, Germany)》1992,70(8):674-682
Summary Renal failure after heart transplantation (HTx) still remains a serious problem, especially when cyclosporin A is used for immunosuppression in the early postoperative therapy. To preserve good renal function without reducing immunosuppressive cyclosporin A treatment, we administered urodilatin (CDD/ANP-95-126) in a long-term, low-dose infusion in addition to the usual medication after heart transplantation. From November 1990 to June 1991, 51 patients (46 male and 5 female; mean age 48 years) were treated with a 620 ng/kg bw·min infusion for 96 h after HTx. The renal function and hemodynamic parameters of these urodilatin-treated patients were compared in this sequential study with 40 patients (33 male and 7 female; mean age 49 years) who had undergone HTx previously from May to November, 1990, as controls. In this phase IIa study, both groups did not differ significantly with respect to age, sex, indication for HTx, and preoperative renal function. In comparison with controls patients treated with urodilatin had a significantly better renal function: a reduction in the peak plasma creatinine (PC values day 4 : 1.5 ± 0.11 vs. 2.19 ± 0.19 mg/dl; P = 0.002), a lower peak serum urea (SU values day 4 : 109 ± 8 vs. 154.7 ± 8.94 mg/dl ; P = 0.0036), and a lower incidence of hemodialysis (6% vs. 10%) were observed. Adequate diuresis was maintained in spite of the reduction of furosemide by more than 60% (P = 0.005) on each day of urodilatin infusion in comparison with controls. The mean central venous pressure was significantly lower by about 50% (P = 0.02) during the administration of urodilatin in spite of reduced vasodilator medication with nitroglycerin. From this phase IIa study, we may conclude that urodilatin could be an important drug in intensive care treatment. For patients undergoing HTx, this peptide seems to be indicated for the improvement of renal function and cardiovascular status, especially in postoperative therapy using high-dose cyclosporin A treatment.Abbreviations ACE
angiotensin converting enzyme
- ANP
atrial natriuretic polypeptide
- ATG
antithymocyte globulin
- bpm
beats per minute
- bw
body weight
- CDD
cardiodilatin
- CDD/ANP-99-126
circulating form of vasorelaxant cardiac peptide
- CHD
coronary heart disease
- CyA
cyclosporin A
- DCM
dilated cardiomyopathy
- GLM
general linear model
- hANP
human atrial natriuretic polypeptide
- HTx
heart transplantation
- NTG
nitroglycerine
- PC
plasma creatinine
- SU
serum urea
- SAS
statistical analysing system 相似文献
33.
The temporal development of autoantibodies was studied in 1,353 offspring of parents with type 1 diabetes. Islet cell antibodies (ICAs) and autoantibodies to insulin (IAAs), glutamic acid decarboxylase, and IA-2 were measured at birth, 9 months, 2 years, and 5 years of age. At birth, no offspring had islet autoimmunity other than maternally acquired antibodies, which were shown to influence antibody prevalence up to age 6 months. Antibodies detected thereafter were likely to represent a true de novo production, since prevalences were the same for offspring from mothers and fathers with diabetes, antibodies detected at 9 months were almost always confirmed in the 2-year sample and were associated with an increased likelihood of having or developing other antibodies. By 2 years of age, autoantibodies appeared in 11% of offspring, 3.5% having more than one autoantibody. IAAs were detected most frequently, and few had autoantibodies in the absence of IAAs. In 23 offspring with multiple islet autoantibodies, IAAs preceded other antibodies in 10 cases and were first detected concurrently with other antibodies in 12 and after detection of other antibodies in 1. Development of additional antibodies and changes in levels, including decline of IAAs at older age, was frequent. Nine children, all with IAAs and ICAs, developed diabetes. Overall cumulative risk for disease by 5 years of age was 1.8% (95% CI 0.2-3.4) and was 50% (95% CI 19-81) for offspring with more than one autoantibody in their 2-year sample. Autoimmunity associated with childhood diabetes is an early event and a dynamic process. Presence of IAAs is a consistent feature of this autoimmunity, and IAA detection can identify children at risk. 相似文献
34.
Koffron A Varghese T Hummel M Yan S Kaufman D Fryer J Leventhal J Stuart F Abecassis M 《Transplantation proceedings》1999,31(1-2):1395-1396
We have shown, for the first time, that TNF induces expression of MCMV IE RNA in the lungs of latently infected mice in the absence of immunosuppression. These initial data suggest that TNF may play an important role in the reactivation of latent MCMV, in the absence of immunosuppression, and provide a provocative insight into the mechanisms of CMV reactivation. Studies are in progress to determine whether genes associated with later stages of the viral life cycle are induced by TNF and whether infectious virus is produced. 相似文献
35.
SCHOLZ J.; ROEWER N.; RUM U.; SCHMITZ W.; SCHOLZ H.; SCHULTE AM ESCH J. 《British journal of anaesthesia》1991,66(6):692-696
-Adrenoceptor stimulation may induce malignant hyperthermia(MH) in vivo. Consequently, we have investigated the effectsof the -adrenoceptor agonist phenylephrine and, for comparison,the effects of the ß-adrenoceptor agonist isoproterenolon inositol-lipid metabolism of malignant hyperthermia susceptible(MHS) and healthy control (MHN) swine. The experiments wereperformed on electrically stimulated (frequency 0.2 Hz) trabeculaeisolated from the right ventricles of the hearts of MHS andMHN animals. After labelling with [3H] inositol for 6 h, differentinositol phosphates were measured by high pressure liquid chromatography,including inositol 1 - phosphate, inositol 1,4-bisphosphate,inositol 1,3,4-trisphosphate, inositol 1,4,5-trisphosphate (1,4,5-IP3)and inositol 1,3,4,5 - tetrakisphosphate. After stimulationwith isoproterenol, the inositol phosphate content did not increaseor vary between muscle from MHS and MHN animals. In contrast,all inositol phosphates increased after stimulation with phenylephrinein both muscle types, the effects being greater in MHS thanin MHN, especially as regards 1,4,5-IP3 content. As 1,4,5-IP3,a presumed second messenger, has been shown to mobilize intracellularcalcium, it is concluded that an enhanced -adrenergic responseis involved in the development of MH.
*Address for correspondence: Abteilung für Anästhesiologie,Universitäts-Krankenhaus Eppendorf, Martinistrasse52, D-2000Hamburg 20, Germany.
Presented in part at the 1989 Meeting of the European Academyof Anaesthesiology in Bonn. 相似文献
36.
SK Roy AM Tomkins SM Akramuzzaman RH Behrens R Haider D Mahalanabis G Fuchs 《Archives of disease in childhood》1997,77(3):196-200
OBJECTIVE: To evaluate the impact of zinc supplementation on the clinical course, stool weight, duration of diarrhoea, changes in serum zinc, and body weight gain of children with acute diarrhoea. DESIGN: Randomised double blind controlled trial. Children were assigned to receive zinc (20 mg elemental zinc per day) containing multivitamins or control group (zinc-free multivitamins) daily in three divided doses for two weeks. SETTING: A diarrhoeal disease hospital in Dhaka, Bangladesh. PATIENTS: 111 children, 3 to 24 months old, below 76% median weight for age of the National Center for Health Statistics standard with acute diarrhoea. Children with severe infection and/or oedema were excluded. MAIN OUTCOME MEASURES: Total diarrhoeal stool output, duration of diarrhoea, rate of weight gain, and changes in serum zinc levels after supplementation. RESULTS: Stool output was 28% less and duration 14% shorter in the zinc supplemented group than placebo (p = 0.06). There were reductions in median total diarrhoeal stool output among zinc supplemented subjects who were shorter (less than 95% height for age), 239 v 326 g/kg (p < 0.04), and who had a lower initial serum zinc (< 14 mmol/l), 279 v 329 g/kg (p < 0.05); a shortening of mean time to recovery occurred (4.7 v 6.2 days, p < 0.04) in those with lower serum zinc. There was an increase in mean serum zinc in the zinc supplemented group (+2.4 v -0.3 mumol/l, p < 0.001) during two weeks of supplementation, and better mean weight gain (120 v 30 g, p < 0.03) at the time of discharge from hospital. CONCLUSIONS: Zinc supplementation is a simple, acceptable, and affordable strategy which should be considered in the management of acute diarrhoea and in prevention of growth faltering in children specially those who are malnourished. 相似文献
37.
This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background. 相似文献
38.
Amicarelli F; Bucciarelli T; Poma A; Aimola P; Di Ilio C; Ragnelli AM; Miranda M 《Carcinogenesis》1998,19(3):519-523
The effects of methylglyoxal on the growth of a line of human melanoma
cells are investigated. Methylglyoxal inhibits cell growth in a dose-
dependent manner and causes an increase in glyceraldehyde 3-phosphate
dehydrogenase, and glyoxalase 1 and glyoxalase 2 specific activities. The
cellular response to increasing concentrations of methylglyoxal in the
culture medium is also studied by measuring L-lactate production,
reduced-oxidized glutathione levels and apoptotic cell death. Methylglyoxal
seems to promote a change of cell population phenotypic repertoire toward a
more monomorphic phenotype. In conclusion, methylglyoxal seems to induce an
enzymatic cellular response that lowers methylglyoxal levels and selects
the most resistant cells.
相似文献
39.
Phenobarbital and clofibrate, two non-genotoxic carcinogens, have been
investigated regarding the relationship between reactive oxygen species,
antioxidant enzyme expression and apoptosis in primary cultures of rat
hepatocytes. Low toxicity concentrations, 200 and 100 microg/ml for
phenobarbital and clofibrate respectively, were used to examine their
effect on spontaneous or transforming growth factor beta1
(TGFbeta1)-induced apoptosis and on the expression of antioxidant defence
enzymes (superoxide dismutases and catalase). The increased incidence of
apoptotic nuclei was visualized in TGFbeta1-treated cultures with the
fluorescent dye Hoechst 33258 and was quantified under all experimental
conditions by measurement of the hypodiploid peak in DNA histograms
obtained by flow cytometry. Both substances, when added separately to
hepatocyte cultures and incubated for 24 and 48 h, significantly diminished
spontaneous apoptosis and exhibited a slight suppression of
TGFbeta1-induced apoptosis. Endogenous peroxide production by hepatocytes
increased with TGFbeta1, phenobarbital or clofibrate and the increase was
greater with phenobarbital and in the presence of TGFbeta1 with both drugs.
Gene expression of catalase and Mn- and Cu,Zn superoxide dismutases (SOD)
was evaluated by northern blot analysis of hepatocytes incubated in the
presence of phenobarbital or clofibrate with or without TGFbeta1 and the
following differences were detected: phenobarbital induced a significant
decrease in both dismutases (to 56%, P < 0.05, and 55%, P < 0.05, for
Mn- and Cu,Zn-SOD respectively) and a 2-fold increase (P < 0.01) in
catalase; clofibrate induced a slight decrease in both SODs and a 4-fold
increase (P < 0.05) in catalase; TGFbeta1 significantly decreased to 37%
(P < 0.05) expression of catalase while not significantly affecting
expression of both SODs. We conclude that inhibition of spontaneous
apoptosis induced by either phenobarbital or clofibrate is accompanied by
increases in the endogenous levels of peroxides and by significant
induction of catalase gene expression. Furthermore, the lack of effect of
both compounds on TGFbeta1-induced apoptosis could be a consequence of the
inability of these two compounds to counteract the depressing effect of
TGFbeta1 on expression of catalase.
相似文献
40.