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901.
Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. A prospective investigation 总被引:36,自引:0,他引:36
S D Boden D O Davis T S Dina N J Patronas S W Wiesel 《The Journal of bone and joint surgery. American volume》1990,72(3):403-408
We performed magnetic resonance imaging on sixty-seven individuals who had never had low-back pain, sciatica, or neurogenic claudication. The scans were interpreted independently by three neuro-radiologists who had no knowledge about the presence or absence of clinical symptoms in the subjects. About one-third of the subjects were found to have a substantial abnormality. Of those who were less than sixty years old, 20 per cent had a herniated nucleus pulposus and one had spinal stenosis. In the group that was sixty years old or older, the findings were abnormal on about 57 per cent of the scans: 36 per cent of the subjects had a herniated nucleus pulposus and 21 per cent had spinal stenosis. There was degeneration or bulging of a disc at at least one lumbar level in 35 per cent of the subjects between twenty and thirty-nine years old and in all but one of the sixty to eighty-year-old subjects. In view of these findings in asymptomatic subjects, we concluded that abnormalities on magnetic resonance images must be strictly correlated with age and any clinical signs and symptoms before operative treatment is contemplated. 相似文献
902.
Studies were undertaken to determine if computed tomography (CT) could reliably assist physical examination in the initial assessment of blunt abdominal trauma, and also to examine how various abdominal injuries were managed with the guidance of CT. A total of 255 patients underwent emergency abdominal CT following blunt abdominal trauma over a period of seven years. One hundred and fifty two patients had abnormal CT scans, including 58 hepatic, 36 renal, 25 splenic and 9 pancreatic injuries as well as 67 patients with intra-abdominal hemorrhage and 21 patients with free abdominal air. A comparative study on the detection of pneumoperitoneum revealed CT to be far superior to plain radiography. One hundred and three patients had normal CT scans, all of whom were managed nonoperatively, except for three false-negative cases and two nontherapeutic cases. The patients with injury to the parenchymal organs were given nonoperative treatment if they had stable vital signs and no evidence of associated injuries demanding immediate surgery and the majority of these patients were managed well nonoperatively. CT was thus found to be a useful adjunct in the management of victims of blunt abdominal trauma, since in a rapid and noninvasive fashion, CT accurately defined the extent of parenchymal organ injury and also disclosed any other abdominal injuries. 相似文献
903.
A Kubota A Okada K Imura H Kawahara R Nezu S Kamata Y Takagi 《Journal of pediatric surgery》1990,25(6):618-621
The effect of metronidazole (MNZ) on hepatic dysfunction associated with total parenteral nutrition (TPN) in neonates was investigated. Neonates receiving TPN for more than 2 weeks were divided into three groups. In group 1, TPN was given alone, in group 2, 25 mg/kg/d of MNZ was administered intravenously for the first 2 weeks of TPN, and in group 3, 50 mg/kg/d of MNZ was given for the first 3 weeks of TPN. Several parameters of liver function tests (LFTs) during the first 4 weeks of TPN were compared among these three groups. There was no significant difference of these parameters between group 1 and group 2. Although there was no significant difference of alkaline phosphatase, gamma-glutamyl transpeptidase, direct bilirubin, and total bile acid between groups 1 and 3, transaminase (glutamic oxaloacetic, glutamic pyruvic) of group 3 remained significantly lower than those of group 1. In conclusion, the administration of MNZ 50 mg/kg/d for 3 weeks, at least, prevented the elevation of transaminase during TPN in neonates, suggesting the possible involvement of intestinal anaerobic flora in the pathogenesis of TPN-associated liver dysfunction. 相似文献
904.
Since 1987, 80 hydroxyapatite-coated (HA) cementless total hip prostheses have been implanted. Thirty patients were examined 21 months postoperatively and the results compared with data for uncoated prosthesis. Earlier mobilization and freedom from pain, together with evidence of bone ingrowth without connective tissue membrane formation, confirmed the benefits of HA-coated prostheses. 相似文献
905.
Absence of HIV antigens in renal tissue from patients with HIV-associated nephropathy 总被引:3,自引:0,他引:3
G Barbiano di Belgiojoso A Genderini L Vago C Parravicini S Bertoli N Landriani 《Nephrology, dialysis, transplantation》1990,5(7):489-492
HIV-associated nephropathy (HIV-N) is considered a distinctive disease, the pathogenesis of which is still undefined. Direct virus-induced renal cell damage has been postulated. The numerous cytolytic ultrastructural changes and a few studies by immunoperoxidase support this hypothesis, but there has been no demonstration of virus by electron-microscopy (EM) or by tissue culture. In seven out of 12 cases with histological characteristics of HIV nephropathy, with proteinuria (five cases) or with nephrotic syndrome (two cases), we tested renal tissue for HIV antigens: core p18 and p25; envelope gp45 and gp110, by means of immunoperoxidase avidin-biotin complex monoclonal antibodies (MoAbs). Light-microscopy (LM) showed in five patients a focal and segmental glomerular sclerosis, and in two a mesangial hyperplasia with vacuolisation of visceral epithelium and protein inclusions. Electron-microscopy, performed in five of seven patients, showed several protein inclusions in podocyte cytoplasm, tubuloreticular inclusions in endothelial cell cytoplasm in all cases, nuclear degranulation of tubular cells in four cases and nuclear bodies in two. HIV antigens by MoAbs on renal tissue were negative in all cases, in both glomeruli and tubules. These results do not confirm the presence of HIV proteins in renal tissue of patients with HIV nephropathy. A possible explanation, apart from no direct HIV in the disease, may be the low viral load in tissues, because of the early phases of renal damage in most cases. 相似文献
906.
Uptake of Adriamycin in tumour and surrounding brain tissue in patients with malignant gliomas 总被引:1,自引:0,他引:1
H. von Holst E. Knochenhauer H. Blomgren V. P. Collins L. Ehn M. Lindquist G. Norén C. Peterson 《Acta neurochirurgica》1990,104(1-2):13-16
Summary Eight patients with malignant gliomas verified on CT scan, received an intravenous injection of 50 mg of Adriamycin R, 24 hours prior to surgical removal of the tumour. Peroperatively, both tumour and surrounding tissue specimens were obtained for determination of the tissue concentrations of Adriamycin and its reduced metabolite Adriamycinol. It was found that Adriamycin could be detected in tumour tissue from all patients. The concentration varied between 0,9 and 4,6 nmol/g tissue. In contrast, Adriamycin could only be detected in surrounding brain tissue from one patient.In anin vitro study a human malignant glioma cell line (U-251 MG) was exposed to various concentrations of Adriamycin for 24 hours. It was found that an intracellular drug concentration above 30 nmol/g cells caused a concentration dependent inhibition of cell growth. Thus, it is likely that the poor effect of Adriamycin on patients with malignant gliomas is due to an ineffective drug accumulation in the tumour tissue. 相似文献
907.
Long-term follow-up of patients with adolescent idiopathic scoliosis treated conservatively: an analysis of the clinical value of progression 总被引:1,自引:0,他引:1
In a retrospective study, 217 patients with conservatively treated adolescent idiopathic scoliosis (AIS) were investigated. Forty-nine cases were operated and 168 were treated only conservatively and had been out of the brace for at least 4 years at the time of the investigation. The progression between cessation of brace treatment and follow-up (a mean of 6.9 years later) was 5.1 degrees. Almost all progression (4.5 degrees) occurred within 2 years of the end of weaning, however. The incidence of failure with regard to the length of follow-up was also studied. A follow-up of 2 years was sufficient to predict with great accuracy (97%) all incidences of failure. 相似文献
908.
Hydroxylation of chlorzoxazone as a specific probe for human liver cytochrome P-450IIE1 总被引:10,自引:0,他引:10
R Peter R B?cker P H Beaune M Iwasaki F P Guengerich C S Yang 《Chemical research in toxicology》1990,3(6):566-573
Human cytochrome P-450IIE1 has been implicated in the oxidation of a number of substrates, including protoxins and -carcinogens. To date, no drugs have been identified that are exclusive substrates for the protein and are applicable for use as noninvasive probes of the in vivo function of the enzyme in humans. Chlorzoxazone was found to be oxidized only to 6-hydroxychlorzoxazone in human liver microsomes. Results of steady-state kinetics are consistent with the view that only a single enzyme catalyzes the reaction. The microsomal reaction was strongly inhibited by rabbit anti-P-450IIE1 and, in a competitive manner, by known P-450IIE1 substrates. Rates of chlorzoxazone 6-hydroxylation in different human liver microsomal preparations were well correlated with levels of immunochemically measured P-450IIE1 and rates of (CH3)2NNO oxidation. Chlorzoxazone 6-hydroxylation was also found to be catalyzed by purified human liver P-450IIE1. These results provide strong evidence that P-450IIE1 is the primary catalyst of chlorzoxazone 6-hydroxylation in human liver. Rates of chlorzoxazone 6-hydroxylation vary considerably among human liver samples, and chlorzoxazone 6-hydroxylation may have potential use as a noninvasive probe in estimating the in vivo expression of human P-450IIE1 and its significance as a risk factor in the toxicity and carcinogenicity of a number of solvents, nitrosamines, and drugs. 相似文献
909.
910.
G M Pacifici A Viani M Franchi S Santerini A Temellini L Giuliani M Carrai 《British journal of clinical pharmacology》1990,30(3):427-435
1. The activities of microsomal glucuronyltransferase and thiomethyltransferase, and those of cytosolic sulphotransferase, acetyltransferase, glutathione transferase and thiomethyltransferase were measured in abnormal (cirrhosis and chronic hepatitis) and normal livers. 2. Glucuronyltransferase and sulphotransferase were investigated with 2-naphthol and ethinyloestradiol as substrates. p-Aminobenzoic acid, benzo(a)pyrene-4,5-epoxide and 2-mercaptoethanol were the substrates of acetyltransferase, glutathione transferase and thiomethyltransferase, respectively. 3. Enzyme activities are expressed as nmol min-1 incubation mg-1 protein and the averages (+/- s.d.) are given. With 2-naphthol as substrate, the glucuronyltransferase activity was 6.55 +/- 4.10 (abnormal liver, n = 33) and 7.81 +/- 4.02 (normal liver, n = 26) (NS); whereas sulphotransferase activity was 0.28 +/- 0.18 (abnormal liver, n = 35) and 0.68 +/- 0.43 (normal liver, n = 26) (P less than 0.01). Glucuronyltransferase activity towards ethinyloestradiol was 102.5 +/- 56.9 (abnormal liver, n = 30) and 107 +/- 59.9 (normal liver, n = 26) (NS), whereas sulphotransferase activity was 57.2 +/- 36.0 (abnormal liver, n = 35) and 122 +/- 67.6 (normal liver, n = 28) (P less than 0.01). Acetyltransferase activity was 0.84 +/- 0.83 (abnormal liver, n = 35) and 3.84 +/- 1.65 (normal liver, n = 26) (P less than 0.01). Glutathione transferase activity was 0.83 +/- 0.68 (abnormal liver, n = 35) and 2.90 +/- 1.59 (normal liver, n = 25) (P less than 0.01) and thiomethyltransferase activity was 1.00 +/- 0.69 (abnormal liver, n = 34) and 3.99 +/- 1.49 (normal liver, n = 25) (P less than 0.01). 4. Liver disease lowers the activities towards the substrates studied of sulphotransferase, acetyltransferase, glutathionetransferase and thiomethyltransferase but not that of glucuronyltransferase.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献