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71.
The uptake of NM394, a new quinolone, by and its subsequent elution from human polymorphonuclear leukocytes were studied and compared with those of ofloxacin and ciprofloxacin. The kinetics of the uptake of NM394 was similar to that of ciprofloxacin. The maximum intracellular-to-extracellular concentration ratio was 12.3, compared with 8.6 for ciprofloxacin and 4.9 for ofloxacin at the extracellular concentration of 20 micrograms/ml. The elution of NM394 from human polymorphonuclear leukocytes occurs relatively slowly; 5 min after the removal of extracellular NM394, nearly 100% still remained in polymorphonuclear leukocytes, compared with ofloxacin, which was so rapidly eluted that only 12% remained. The uptake of NM394 was significantly decreased at 4 degrees C and by the presence of NaCN but was not affected by the presence of L-glycine, L-leucine, L-serine, adenosine, or NaF. NM394 showed intracellular activity at a concentration of 0.1 microgram/ml that significantly reduced the number of phagocytosed Pseudomonas aeruginosa cells with 2 h of incubation. These results suggest that uptake of NM394 by human polymorphonuclear leukocytes occurs via an active transport system differing from that of ofloxacin, whose uptake is affected by the presence of L-glycine and L-leucine, and that once accumulated, NM394 remains intracellularly active and participates in protection against bacterial infection.  相似文献   
72.
The m.3302A>G mutation in the mitochondrial tRNALeu(UUR) gene has been identified in only 12 patients from 6 families, all manifesting adult-onset slowly progressive myopathy with minor central nervous system involvement. An 11-year-old boy presented with progressive proximal-dominant muscle weakness from age 7 years. At age 10, he developed recurrent stroke-like episodes. Mitochondrial myopathy, encephalopathy, lactic acidosis, plus stroke-like episodes (MELAS) was diagnosed by clinical symptoms and muscle biopsy findings. Mitochondrial gene analysis revealed a heteroplasmic m.3302A>G mutation. Histological examination showed strongly SDH reactive blood vessels (SSVs), not present in previous cases with myopathies due to the m.3302A>G mutation. These findings broaden the phenotypic spectrum of this mutation.  相似文献   
73.
In the major pathway of homologous DNA recombination in prokaryotic cells, the Holliday junction intermediate is processed through its association with RuvA, RuvB, and RuvC proteins. Specific binding of the RuvA tetramer to the Holliday junction is required for the RuvB motor protein to be loaded onto the junction DNA, and the RuvAB complex drives the ATP-dependent branch migration. We solved the crystal structure of the Holliday junction bound to a single Escherichia coli RuvA tetramer at 3.1-A resolution. In this complex, one side of DNA is accessible for cleavage by RuvC resolvase at the junction center. The refined junction DNA structure revealed an open concave architecture with a four-fold symmetry. Each arm, with B-form DNA, in the Holliday junction is predominantly recognized in the minor groove through hydrogen bonds with two repeated helix-hairpin-helix motifs of each RuvA subunit. The local conformation near the crossover point, where two base pairs are disrupted, suggests a possible scheme for successive base pair rearrangements, which may account for smooth Holliday junction movement without segmental unwinding.  相似文献   
74.
We determined the MICs of ampicillin, methicillin, cefaclor, cefixime, cefteram, ofloxacin and ciprofloxacin against a total of 1,448 strains from 11 species: 464 strains of Staphylococcus aureus, 306 strains of Streptococcus pneumoniae, 114 strains of Streptococcus pyogenes, 37 strains of Branhamella catarrhalis, 329 strains of Haemophilus influenzae, 32 strains of Escherichia coli, 66 strains of Klebsiella pneumoniae, 26 strains of Enterobacter cloacae, 20 strains of Serratia marcescens, 12 strains of Pseudomonas aeruginosa and 42 strains of Acinetobacter calcoaceticus, isolated from the throat swab and the sputum of 2,539 patients with respiratory infections who visited 21 private clinics in Tohoku district of Japan during the period from January to April in 1989. Ciprofloxacin and ofloxacin were more active against S. aureus, B. catarrhalis, P. aeruginosa and A. calcoaceticus than other antibiotics. Ampicillin and cefteram were more active against S. pneumoniae and S. pyogenes than other antibiotics. New-quinolones and cephems of new-generation were active against H. influenzae, E. coli, K. pneumoniae, E. cloacae and S. marcescens. Of 30 strains of S. aureus which were resistant (MIC greater than or equal to 12.5 micrograms/ml) to ampicillin, only one strain was resistant (MIC greater than or equal to 12.5 micrograms/ml) to methicillin. Twenty strains (6.5%) of S. pneumoniae and 49 strains (14.9%) of H. influenzae were resistant (MIC greater than or equal to 1.56 micrograms/ml) to ampicillin. Of 101 strains of H. influenzae of which their beta-lactamase activity was determined by Nitrocephin-method, 27 (26.7%) were beta-lactamase-positive strains. The above results indicated that MRSA is only rarely found in primary care clinics but the incidence of ampicillin-resistant H. influenzae in primary care clinics is almost the same as that of the intensive care clinic, i.e. medical school-affiliated hospitals. Therefore caution should be exercised as regards antibiotic resistance of the causative organism even in primary care clinics.  相似文献   
75.
A patient with transpyloric prolapse of a pedunculated polypoid gastric carcinoma is reported. Only three previous cases have been reported in the international literatures. However, in Japan, 33 cases of prolapsed gastric carcinoma have been reported during the past 30 years. Prolapsed gastric carcinoma should be included in the differential diagnosis of localized intraluminal filling defects in the duodenal bulb. Endoscopy and biopsy are essential for correct diagnosis.  相似文献   
76.
Pearson marrow-pancreas syndrome, a fatal disease associated with mitochondrial DNA rearrangements, is characterized by refractory sideroblastic anaemia during infancy. Only a few neonates with Pearson syndrome have been reported with metabolic acidosis. A female neonate who exhibited severe metabolic acidosis and anaemia at birth is described here. Her condition progressively worsened, with pancytopenia and uncontrollable metabolic acidosis resulting in death at the age of 14 days. A 4988-base pair deletion of mtDNA was detected in the patient's leukocytes, liver and muscle. When a neonate exhibits severe metabolic acidosis of unknown cause, the possibility of Pearson syndrome should be considered.  相似文献   
77.
We have isolated and characterized two overlapping cDNA clones for Arabidopsis thaliana squalene synthase. Their nucleotide sequences contained an open reading frame for a 410-amino acid polypeptide (calculated molecular mass, 47 kDa). The deduced amino acid sequence of the Arabidopsis polypeptide was significantly homologous (42-44% identical) to the sequences of known squalene synthases of several species, from yeast to man, but it was much less homologous to that of tomato phytoene synthase. To express the Arabidopsis enzyme in Escherichia coli, the entire coding region was subcloned into an expression vector. A cell-free extract of E. coli transformed with the recombinant plasmid, in the presence of NADPH and Mg2+, efficiently converted [14C]farnesyl diphosphate into squalene. On the other hand, in the absence of NADPH and the presence of Mn2+, the cell-free extract formed dehydrosqualene as a secondary product. Another E. coli extract expressing mouse squalene synthase showed the same activity as the Arabidopsis enzyme. Therefore, both the structure and reaction mechanism of squalene synthases are markedly conserved in taxonomically remote eukaryotes.  相似文献   
78.
Zusammenfassung Die anaerobe Glykolyse bei Ehrlich-Ascitestumorzellen wurde durch GA und GAL (10–2 M) um etwa 45% bzw. 35% gehemmt. N-Acetyl-d-Glucosamin und NGAL-Zusatz hatte keine Wirkung. Durch Hefehexokinase wurden GA und GAL in einem geringeren Ausmaß phosphoriliert als Glucose. Die Phosphorilierung der Glucose wurde durch GA um 28%, durch GAL um 20% gehemmt.Die endogene Atmung von Tumorzellen des Ehrlich-Ascitestumors und des Asciteshepatoms (AH-130) wurde durch GA in etwa dem gleichen Ausmaß wie durch Glucose (um etwa 45%) gehemmt. Der Crabtree-Effekt wurde durch GA verstärkt, durch GAL dagegen etwas abgeschwächt. Die atmungshemmende Wirkung von Glucose und GA wurde durch IAA bzw. KF nur wenig verändert. Die hemmende Wirkung von GA wurde durch DNP fast völlig aufgehoben, die der Glucose nur in den ersten 30 min.Die Glutaminase-I Aktivität bei Ehrlich-Ascitestumorzellen war vier- bis fünfmal höher als in der Leber von krebstragenden und gesunden Mäusen. Die Fermentaktivität wurde durch Glucose um 45%, durch GA um 35%, durch GAL um 10% und durch Glutaminsäure fast völlig gehemmt. Bei Inkubation der Tumorzellen mit GA eine größere Menge Ammoniak freigesetzt.Die Überlebenszeit von Ehrlich-Ascitestumor tragenden Mäusen wurde durch eine intraperitoneale Behandlung der Tiere mit GA verlängert.
Summary Glucosamine and GAL inhibited the anaerobic glycolysis of Ehrlich ascites tumor cells by 45% and 35% respectively, but NGA and NGAL showed no effect. GA and GAL were phosphorylated less by yeast-hexokinase than was glucose. The phosphorylation of glucose was inhibited about 28% by GA and about 20% by GAL. The endogenous respiration of the cells of Ehrlich ascites tumor and of ascites hepatoma (AH-130) was inhibited by GA to about the same degree as by glucose (about 45%). The Crabtree effect of glucose control was increased by GA; in contrast, it was somewhat decreased by GAL. The respiratory inhibiting effect of glucose and GA were changed little with IAA or KF. The inhibiting effect of GA was almost completely abolished by DNP; that of glucose only in the first 30 min.The activity of glutaminase-I of Ehrlich ascites tumor cells was 4–5 times greater than that of the liver of tumor-bearing or healthy mice. The enzymatic activity was inhibited by glucose about 45%, by GA about 35%, by GAL about 10%, and by glutaminic acid completely. When the tumor cells were incubated with GA, NH3 was liberated in large amounts, probably as the result of enzymatic deamination.The mice with Ehrlich ascites tumors survived longer after intraperitoneal injection of GA than control animals.


Mit 4 Textabbildungen

Mitteilung 40 der pharmakologischen Untersuchungen über den Stoffwechsel von Geschwulstgewebe.

Diese Arbeit erfolgte mit der Unterstützung von U.S. Public Health Service Grant No. CY-5257.

Herren Dr. G. Hertting, Dr. E. Stocklasker, Dr. O. Hornykiewicz und Dr. H. Iwata danken wir heirmit für ihre Hilfe bei der Übersetzung dieser Abhandlung.  相似文献   
79.
The standard treatment for autoimmune pancreatitis (AIP) is steroid therapy, although some patients improve spontaneously. Indications for steroid therapy in AIP patients are symptoms such as obstructive jaundice, abdominal pain, back pain, and the presence of symptomatic extrapancreatic lesions. Prior to steroid therapy, obstructive jaundice should be managed by biliary drainage, and blood glucose levels should be controlled in patients with diabetes mellitus. The recommended initial oral prednisolone dose for induction of remission is 0.6 mg/kg/day, which is administered for 2–4 weeks. The dose is then tapered by 5 mg every 1–2 weeks, based on changes in clinical manifestations, biochemical blood tests (such as liver enzymes and IgG or IgG4 levels), and repeated imaging findings (US, CT, MRCP, ERCP, etc.). The dose is tapered to a maintenance dose (2.5–5 mg/day) over a period of 2–3 months. Cessation of steroid therapy should be based on the disease activity in each case. Termination of maintenance therapy should be planned within 3 years in cases with radiological and serological improvement. Re-administration or dose-up of steroid is effective for treating AIP relapse. Application of immunomodulatory drugs is considered for AIP patients who prove resistant to steroid therapy. The prognosis of AIP appears to be good over the short-term with steroid therapy. The long-term outcome is less clear, as there are many unknown factors, such as relapse, pancreatic exocrine or endocrine dysfunction, and associated malignancy.  相似文献   
80.

Background

In response to the proposal of the international consensus diagnostic criteria (ICDC) for autoimmune pancreatitis (AIP) and the Japanese diagnostic criteria in 2011, the 2009 Japanese consensus guidelines for managing AIP required revision.

Methods

Three committees [the professional committee for making clinical questions (CQs) and statements by Japanese specialists, the expert panelist committee for rating statements by the modified Delphi method, and the evaluating committee by moderators] were organized. Fifteen specialists for AIP extracted the specific clinical statements from 1,843 articles published between 1963 and 2012 (obtained from Pub Med and a secondary database, and developed the CQs and statements. The expert panel individually rated the clinical statements using a modified Delphi approach, in which a clinical statement receiving a median score greater than seven on a nine-point scale from the panel was regarded as valid.

Results

The professional committee created 13 CQs and statements for the current concept and diagnosis of AIP, 6 for extra-pancreatic lesions, 6 for differential diagnosis, and 11 for treatment.

Conclusion

After evaluation by the moderators, amendments to the Japanese consensus guidelines for AIP have been proposed for 2013.  相似文献   
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