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1.
The effect of electric charge on the hepatic disposition of macromolecules was studied in the rat. Charged derivatives of dextran (T-70) and bovine serum albumin (BSA), mitomycin C–dextran conjugates (MMC-D), and lactosaminated BSA (Lac-BSA) were employed as model macromolecules. After intravenous injection, cationic macromolecules were rapidly eliminated from plasma because of their extensive hepatic uptake, while anionic and neutral macromolecules were slowly eliminated. Cationic macromolecules were recovered from parenchymal and nonparenchymal hepatic cells at a cellular uptake (per unit cell number) ratio of 1.4–3.2, while that of Lac-BSA was 14. During liver perfusion using a single-pass constant infusion mode, cationic macromolecules were continuously extracted by the liver, with extraction ratios at steady-state (E ss) ranging between 0.03 and 0.54, whereas anionic and neutral macromolecules were almost completely recovered in the outflow at steady state. The E ss for cationized BSA (Cat-BSA) and cationic MMC-Dcat were concentration dependent and decreased at low temperatures and in the presence of colchicine and cytochalasin B. The possible participation of the internalization process in the uptake of cationic macromolecules by hepatocytes was suggested.  相似文献   
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Transurethral resection of urinary bladder tumor was performed under spinal anesthesia which has been considered to be rather contraindicated in a patient with idiopathic hypertrophic cardiomyopathy. Caution was exercised not to compromise myocardial oxygen supply demand ratio. Central venous pressure (CVP) was continuously monitored and crystalloid solution was infused to maintain CVP in pre-anesthetic level, thereby preventing the reduction in arterial pressure. The patient was hemodynamically stable throughout the operation. This case indicates that if adequate preload could be preserved and hypotension avoided, spinal anesthesia may not be precluded in patients with idiopathic hypertrophic cardiomyopathy.  相似文献   
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Combined small cell and non-small cell carcinoma is relatively rare in the lung. Examination of the clonal relationship of different components in this type of tumor may give a clue to the rarity. We retrieved 6 such tumors; all 6 had small cell carcinoma and adenocarcinoma components, and 3 had an additional squamous cell carcinoma component. We examined the point mutations in the p53 gene and allelic loss (ie, the loss of heterozygosity [LOH] pattern) of chromosome 3p in each component. p53 mutations were detected in the small cell carcinoma component of 5 tumors and in the non-small cell carcinoma components of 2 tumors. In 1 case, the squamous cell carcinoma component had a p53 mutation locus identical to that in the small cell carcinoma component, but in the other case, the adenocarcinoma component had a different mutation than that in the small cell carcinoma component. Chromosome 3p LOH loci in the squamous cell carcinoma component were present in the small cell carcinoma component in all 3 cases, but some LOH loci were not identical in the small cell carcinoma and adenocarcinoma components in 3 cases. These results suggest that the small cell and squamous cell carcinoma components of combined small cell lung carcinomas have an intimate clonal relationship. On the other hand, the adenocarcinoma component often may be derived from a separate clone or, more likely, undergo a progressive process separate from the squamous cell-small cell carcinoma beginning in a very early stage, that is, before the appearance of p53 and chromosome 3p abnormalities. This tumorigenesis process may explain the relative rarity of combined small cell and non-small cell carcinoma, which occurs primarily in the peripheral lung, an infrequent site of squamous cell carcinoma.  相似文献   
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Prefixation treatment of cultured human bone marrow cells with a DNA intercalating agent, ethidium bromide (EBr), induced a dose- and time-related elongation of chromosomes. When compared with EBr-free cultures, a 2.9-fold increase in the yield of early mitotic cells with more than 400 bands per haploid set of chromosomes was achieved by simply adding 10 micrograms/ml of EBr during the last 2 hours of culture. The proportion of early mitotic cells was equal to that obtained in methotrexate synchronized cultures. Fluorescence banding methods using base composition specific agents actinomycin D/DAPI for AT base pairs and chromomycin A3/distamycin A for GC suggested that EBr does not have base specificity, because EBr did not alter the banding patterns of chromosomes obtained with these staining procedures.  相似文献   
7.
Glutathione metabolism in red cell aging   总被引:2,自引:0,他引:2  
Normal human red cells were centrifugally separated according to age by discontinuous density gradient of Percoll. Reduced glutathione (GSH), GSH stability and glucose-6-phosphate dehydrogenase (G6PD) activity in fractionated red cells decreased with age, while oxidized glutathione (GSSG) and methemoglobin (MetHb) increased with age.  相似文献   
8.

Background  

Nonalcoholic steatohepatitis (NASH) is a feature of metabolic syndrome. Advanced glycation end-products (AGEs) are formed by the Maillard reaction, which contributes to aging and to certain pathological complications of diabetes. A recent study has suggested that glyceraldehyde-derived AGEs (Glycer-AGEs) are elevated in the sera of patients with NASH. Furthermore, immunohistochemistry of Glycer-AGEs showed intense staining in the livers of patients with NASH. The present study aimed to examine the effect of intracellular Glycer-AGEs on hepatocellular carcinoma (Hep3B) cells.  相似文献   
9.
The effect of cianidanol on the HBeAg/anti-HBe system in 338 patients with HBeAg-positive chronic hepatitis was studied in a double-blind, randomised, placebo-controlled, multicentre clinical trial. 174 patients received cianidanol in a daily dose of 1.5 g for 2 weeks, followed by 2.25 g for a further 14 weeks. 164 patients received a placebo for the same period: patients were followed up for a further 8 weeks. HBeAg and anti-HBe antibody titers were measured by R.I.A. at 4-week intervals and the results were expressed as a "cut-off index" and "inhibition percent", respectively. Liver function tests were also monitored at the same intervals. The HBeAg titer decreased by at least 50% in 44 of 144 cases treated with cianidanol (21 of 140 cases treated with placebo). The difference was significant (p less than 0.01). The HBeAg disappeared in 16 of the cianidanol cases and four of the placebo (p less than 0.05) and a seroconversion was observed in six cianidanol patients and three placebo patients. The mean HBeAg titer in the cianidanol group was significantly lower than that in the placebo group at the end of the 16 weeks of therapy (p less than 0.05). The patients whose HBeAg titer was lowered were largely those with chronic active hepatitis and had higher initial values of SGPT, SGOT and gamma-globulin than the patients whose HBeAg titers remained unchanged. The mean values for these liver function tests also fell significantly in the former sub-group. The drug was well tolerated, the only notable side effect being a transient febrile reaction in 13 patients. It is concluded that cianidanol is a useful and well-tolerated drug for improving the HBeAg/anti-HBe system in patients with HBeAg-positive chronic active hepatitis.  相似文献   
10.
To evaluate the role of the Ala45Thr variant of BETA2/NEUROD1 in the development of type 1 or type 2 diabetes, we studied a Japanese population consisting of 383 control subjects, 234 type 1 diabetes patients and 160 type 2 diabetes patients. Both genotypewise and allelewise, there was no significant association of the variant with type 1 diabetes or type 2 diabetes in Japanese. Also, there were no significant differences in clinical characteristics with and without the variant. Our present results do not support a recent report which described an association of the Ala45Thr variant with type 1 diabetes in Japanese.  相似文献   
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