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121.
Quantitative measurement of hepatitis C virus (HCV) RNA is useful in patients with chronic hepatitis C, especially with interferon treatment. We examined the clinical usefulness of the AMPLICOR monitor assay, a newly developed assay for quantitative measurement, by comparing it with two other assays with different principles. A total of 48 patients with chronic hepatitis C who were treated with interferon-α (IFN-α) were studied: 19 were complete responders and 29 were non-responders. Hepatitis C virus RNA was measured quantitatively by AMPLICOR, branched DNA (bDNA) probe, and competitive polymerase chain reaction (C-PCR) assays. An internal quantification standard was used in the AMPLICOR assay. A cDNA competitor with a deletion of 15 base pairs in the middle portion was used in the C-PCR method. The concentration of HCV RNA was significantly correlated between the three assays adopted in this study. Sensitivity of assays was 100% by C-PCR, 90% by AMPLICOR and 69% by bDNA assays. The active quantitative range was best with the C-PCR assay and worst with the bDNA assay. The bDNA assay had a tendency to exhibit lower values for patients with serotype 2 than did the other two assays. The predictive rate of the long-term response to IFN-α therapy, before its initiation, was over 75% in all three assays. The predictive rate just after completing IFN-α therapy was as high as 80% by C-PCR and the AMPLICOR assays, but was low (58%) with the bDNA assay. The handling of the bDNA and AMPLICOR assays was much easier than the C-PCR assay, which required time and skill. These results indicate that the AMPLICOR assay is a simple and reliable method for measuring the serum concentrations of HCV RNA, and thus is suitable for clinical application.  相似文献   
122.
In the present study, we examined the effects of interleukin-3 (IL-3) on the proliferation of leukaemic progenitor cells from 11 Japanese patients with acute myeloblastic leukaemia (AML), including the effect of its combination with granulocyte/macrophage colony-stimulating factor (GM-CSF) or granulocyte colony-stimulating factor (G-CSF). The results showed that IL-3 sufficiently stimulated the proliferation of AML progenitor cells in almost all the cases examined, and that the stimulation pattern of IL-3 was similar to that of GM-CSF, although different from that of G-CSF. Furthermore, IL-3 worked synergistically with G-CSF, whereas IL-3 and GM-CSF together were less actively synergistic (P < 0.05). These findings suggest the possibility of IL-3/G-CSF/cytosine arabinoside (Ara-C) combination therapy, which may be able to enhance the cytotoxic effect of Ara-C on AML progenitor cells powerfully in a wider range of patients including cases refractory for IL-3/Ara-C combination therapy.  相似文献   
123.
Abstract To study the influence of transcatheter arterial embolization therapy (TAE) on the portal tracts, 32 cases of hepatocellular carcinoma (HCC) with a history of TAE were examined. Portal tract elements are said to be mainly supplied by hepatic arterial blood, as is HCC. The following changes were found: peribile duct fibrosis; biliary epithelial injuries; bile duct necrosis; fibrous thickening of the intima and adventitia of arteries; thrombosis or stenosis of portal vein branches; and fibrosis of portal tract itself. We failed to correlate these histopathologic changes with the frequency of TAE or the interval between TAE therapy and surgery or autopsy. Semi-quantitative assessment disclosed that vessels of the peribiliary vascular plexus (PVP) which are known to be derived from hepatic arterial branches, were considerably decreased. There was little correlation between the degree of reduction of PVP and the observed histopathologic changes of portal tracts. It is suggested that TAE causes adverse effects on the elements of portal tracts and a reduction in the PVP in the vicinity of HCC, but the relationship between them is unclear.  相似文献   
124.
Abstract The aim of this study was to assess the effects of nicotine on the gastric epithelial restoration using primary cultured rabbit gastric mucosal cell model.
Confluent monolayer mucosal cell sheets consisting of mainly mucous cells were wounded using a rotating silicon tip. The process of restoration was monitored, and the size of wound was measured and analysed quantitatively.
Artificial wounds recovered in 36 h in controls. The nicotine treatment (10−5, 10−4 and 10−3 mol/L) did not cause any effects on the process of wound repair. Bromodeoxyuridine (BrdU) positive cells appeared around the wound 24-36 h after injury and then disappeared after the complete repair in controls and also in nicotine-treated groups. However, in the morphological observation, numerous vacuoles were detected in parietal cells of nicotine-treated groups. This effect of nicotine was reversible by removing nicotine from the medium. Present data suggest that nicotine has no direct effects on the mucosal restoration but might have an effect on the structure and function of parietal cells.  相似文献   
125.
We used endoscopic color Doppler ultrasonography to detect hemorrhagic gastric ulcer, and to determine whether this modality could show blood vessels present deep to ulcers and whether these vessels influenced clinical course. Subjects were 20 patients with hemorrhagic gastric ulcers which had visible vessels on the ulcer base endoscopically. In 11 of 20 patients (group P) color signals indicating blood flow were observed, in which a weak pulsatile wave was detected in five cases. In two operated cases the signals were confirmed as blood vessels histologically. The diameters of these vessels were over 0.35 mm. It was thought that in cases undetectable on endoscopic color Doppler ultrasonography (group N) the diameter of vessels was too narrow or the velocity of blood too slow. There were no differences in the clinical background of group P and group N. However, ulcer bleeding was more severe in group P cases (P<0.05). Many patients in whom blood flow was detected experienced repeated ulcer bleeding as well as ulcer recurrences. Patients with hemorrhagic ulcers and in whom ultrasonic imaging demonstrates blood flow should be managed with great care. (Dig Endosc 1999; 11: 231–235)  相似文献   
126.
A new test using N-benzoyl-L-tyrosyl-p-aminobenzoic acid (N-BT-PABA) for an evaluation of exocrine pancreatic function was compared with a pancreozymin-secretin test in 38 subjects. Urinary recovery of PABA, which is absorbed from the intestine and conjugated in the liver after an oral administration of N-BT-PABA, depends mainly on chymotrypsin activity. The recovery rate of PABA in urine decreases in chronic pancreatitis, in which chymotrypsin activity in the duodenal juice is disturbed. The recovery rate of PABA in calcifying chronic pancreatitis was 40.2 +/- 15% and significantly less than 81.2 +/- 7.4% in normal subjects (P less than 0.01). The amount of PABA in urine during eight hours was correlated with parameters of volume output- bicarbonate concentration and amylase output stimulated by injections of pancreozymin and secretin (P-S test). The new test using N-BT-PABA is useful for the evaluation of exocrine pancreatic function in general practice.  相似文献   
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Patients with Vitamin D-resistant rickets have abnormal tooth morphology such as thinglobular dentin and enlarged pulp horns that extend into the dentino-enamel junction.Invasion of the pulp by microorganisms and toxins is inevitable. The increasedfibrotic content of the pulp, together with a reduced number of odontoblasts,decreases the response to pulp infection. The most important oral findings arecharacterized by spontaneous gingival and dental abscesses occuring without historyof trauma or caries. Radiographic examinations revealed large pulp chambers, shortroots, poorly defined lamina dura and hypoplastic alveolar ridge. These dentalabscesses are common and therefore the extraction and pulpectomy are the treatment ofchoice. The purpose of this article is to report a case of Vitamin D-resistantrickets in a 5 year-old boy, describing the dental findings and the treatment to beperformed in these cases.  相似文献   
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