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31.
Two patients with adenosquamous cell carcinoma of the colon,who presented severe hypercalcemia, are reported. Adenosquamouscell carcinoma of the colon is relatively rare, and there wereonly two cases among 1,053 patients who were hospitalized withmalignancy in the large intestine at the National Cancer CenterHospital during the past 18 years. Both of these cases presentedlethal hypercalcemia in the absence of osseous metastasis, andthere were no other patients who had malignant tumors of thelarge intestine and presented hypercalcemia. These observationssuggest that there is a close relationship between the squamouscell component and the occurrence of hypercalcemia, as is observedin the case of lung cancer. Radioimmunoactive parathyroid hormonewas undetectable in the plasma and the tumor tissue in thesetwo cases.  相似文献   
32.
Diagnosis of Small Pancreatic Carcinoma   总被引:1,自引:0,他引:1  
A retrospective analysis was performed to evaluate the clinicalsymptoms and abnormal test findings in small pancreatic carcinoma.Five hundred and thirty-six cases of pancreatic carcinoma withthe histology of duct cell carcinoma were collected from 14medical centers in Japan. In 440 of the cases, tumor size wasmeasured at the time of laparotomy or from the resected specimen.Three hundred and seventy-seven patients (86%) had a carcinomalarger than 3.0 cm; only 30% of these were resectable. Sixty-threepatients (14%) had a carcinoma of 3.0 cm or less, with resectabilityof 97%. Detecting a tumor of "3 cm or less" with a high probabilityof resectability is the objective of early diagnosis with theresulting possibility of a cure. In most cases these small carcinomaswere found easily when obstructive jaundice was present (73%).However, the estimated occurrence of obstructive jaundice associatedwith carcinomas of 3 cm or less was only 10% among the totalcases of pancreatic carcinoma studied. Therefore, it is necessaryfor early diagnosis to detect carcinomas of 3 cm or less presentingwithout jaundice. The symptoms of small carcinoma without jaundiceare weight loss, anorexia, upper abdominal pain, back pain anda palpable abdominal mass. Among the various available examinations,endoscopic retrograde cholangiopancreatography, computerizedtomography and ultrasonography were valuable in diagnosing thesesmall carcinomas.  相似文献   
33.
In order to clarlfy the cell kinetics of colorectal villous tumors (VT), 21 villous adenomatous areas and 12 carcinomatous areas within villous adenomas were investigated for proliferative activity and apoptosis and compared with a series of 41 tubular tumors (TT), demonstrating elements of intramucosal carcinomas as well as tubular adenomas (so-called carcinoma in tubular adenoma). Proliferation was estimated in terms of KI-67 labeling indices and mitotic indices, and apoptosis was assessed by DNA nick-end labeling to give apoptotic Indices. Apoptotic indices of villous adenomatous and carcinomatous regions were significantly lower than the values for their tubular counterparts. Kl-67 labeling indices were also significantly lower for adenoma components. Apoptotic indices, Ki-67 labeling indices and mitotic Indices increased with atypia raised in tubular adenoma components. Correlations of mitotic indices with apoptotic indices, Ki-67 labeling Indices with apoptotic indices and mitotic Indices with Ki-67 labeling indices were found for each villous tumor group and tubular tumor group, and the apoptosis and proliferation ratios for villous tumors were relatively low, suggesting a tendency for greater growth due to less cell deletion. Although this is only one of the biological features of villous tumor groups, it might play a major role in generation of malignancy.  相似文献   
34.
While the stimulating effect of concentrated salts on ryanodine receptor (RyR) is widely accepted in Ca2+-induced Ca2+ release (CICR) and [3H]ryanodine binding, the effect of non-ionic solutes on RyR is controversial. We investigated the effects of polyols on [3H]ryanodine binding to α- and β-RyR purified from bullfrog skeletal muscle, and on CICR from sarcoplasmic reticulum (SR) in a skinned frog skeletal muscle fibre. Addition of polyols (glucose, sucrose, sorbitol, glycerol and ethylene glycol) in submolar to molar concentrations to an isotonic salt medium increased dose-dependently Ca2+-activated [3H]ryanodine binding to α- and β-RyR of a similar magnitude. The increase is due to the rise in both apparent affinity (1/KD) and maximal numbers of binding sites (Bmax) for ryanodine. In addition to this stimulating effect, glucose sensitized both isoforms to Ca2+ in the Ca2+-activated reaction, which is distinct in mechanism(s) from caffeine. These stimulating effects of polyols were not observed unless some NaCl was present, which might explain the discrepancy among reported results. Consistent with these findings, polyols reversibly enhanced the rate of CICR from SR in skinned fibres with an increase in the Ca2+ sensitivity. The enhanced CICR was still sensitive to well-known modulators for CICR (Ca2+, Mg2+, adenine nucleotides and procaine), as with [3H]ryanodine binding. The results of this study reveal that polyols stimulate α- and β-RyR in frog skeletal muscle, bringing about increased CICR activity. The finding that the specific activity of polyols in stimulation of [3H]ryanodine binding was approximately proportional to their molecular weights leads us to discuss the possible modification of protein surface--water molecule interaction as an underlying mechanismThis revised version was published online in July 2005 with corrections to the Cover Date.  相似文献   
35.
Abstract Behavior of event related potential (ERP) components in the drowsy state was examined in nine subjects using oddball paradigm. A component with peak latency of 300 msec, N300, was superimposed on ERP in the drowsy state. N300 appeared also in stage 1 of NREM sleep and closely resembled vertex sharp wave evoked by sound stimulation in both scalp distribution and peak latency. It was suggested that N300 recorded in the drowsy state and vertex sharp wave recorded in stage 1 of NREM sleep are generated by the identical synchronizing mechanism in the brain.  相似文献   
36.
Abstract N300 appearing in response to sound stimulus was used as an index to determine the occurrence of cortical activity characterizing REM sleep. In 5/10 subjects, marked reduction of N300 amplitude occurred even in the period of 0.5-2.5 min immediately preceding the appearance of muscle atonia characterizing REM sleep. Neither muscle atonia nor rapid eye movements appeared prior to the marked reduction of N300 amplitude in any subject. This suggests that the cortical activity characterizing REM sleep sometimes occurs a few minutes (or less) earlier than other physiological phenomena.  相似文献   
37.
Abstract Expression of c-fos immunoreactivity was investigated in rat brain after unilateral application of a weak anodal direct current (anodal polarization) to the sensorimotor cortex of rats. Increases in Fos-immunopositive neurons were observed transiently in the neocortex, cingulate cortex, piriform cortex, and hippocampal formation, which were ipsilateral to the polarization, as a function of the duration and intensity of the currrent applied. It is likely that anodal polarization enhances the neuronal activities in the cortex dependent on polarization paradigms.  相似文献   
38.
We report a 59 year old male with obstructive jaundice and a clinical diagnosis of carcinoma of the midportion of the common bile duct. Examination of the surgical specimen revealed a small tumour in the neck of the gall-bladder. Histologic examination revealed the tumour in the common bile duct was an adenosquamous carcinoma whereas that in the gall-bladder was an early papillary adenocarcinoma. Thus, this is a rare case of the simultaneous development of adenosquamous carcinoma and early papillary adenocarcinoma in the biliary tree.  相似文献   
39.
Background and objective: More than 50% of patients with childhood asthma enter clinical remission by puberty, although 40–50% of these people will probably develop asthma symptoms during early adulthood. The mechanism of relapsing asthma in early adulthood remains unclear. This study determined the characteristics of young adults whose asthma remitted either during or before adolescence. Methods: A comparative study was performed on 24 students whose childhood asthma had gone into clinical remission by puberty (remission group), 25 atopic students with no history of asthma (atopy group) and 19 non‐atopic students without allergic diseases (control group). Examinations included spirometry, levels of serum‐specific IgE‐antibodies, airway responsiveness to methacholine, exhaled nitric oxide (eNO) and evidence of airway inflammation in induced sputum. Results: Airway responsiveness (P < 0.01), eosinophil counts in sputum (P < 0.05) and the prevalence of sensitization to Dermatophagoides forinae (P < 0.01) were significantly higher, and FEF25–75% and FEF75% (P < 0.01) were significantly lower in the remission group than in the atopy and control groups. Furthermore, 50% and 33% of the remission group had airway hyper‐responsiveness (AHR) and sputum eosinophilia, respectively. The eNO levels in the remission (P < 0.01) and atopy (P < 0.05) groups were significantly higher than in controls. Remission group members with AHR had a significantly longer period of childhood asthma, a shorter period of remission and greater airway eosinophilic inflammation than those without AHR (P < 0.05). Conclusion: One half of young adults with childhood asthma that remitted either during or before adolescence continued to have evidence of AHR and airway eosinophilic inflammation, and might be at risk of future relapse.  相似文献   
40.
We studied potential indicators of severe acute pancreatitis by measuring the blood concentrations of various cytokines, polymorphonuclear leucocyte elastase (PMN-E), acute phase reactants, pancreatic amylase (P-AMY), pancreatic elastase-1 (E-1) and white blood cell (WBC) counts in patients with acute pancreatitis. In addition, the presence of multiple organ damage was assessed. Subjects consisted of 22 patients with acute pancreatitis including severe (n= 11), moderate (n= 4) and mild (n= 7) cases. A significant positive correlation was observed between the number of organs damaged and the peak concentrations of interleukin (IL)-6, PMN-E, C-reactive protein (CRP) and pancreatic secretory trypsin inhibitor (PSTI). Among these markers, blood concentrations of PMN-E and IL-6 rapidly increased and peaked at the early phase of acute pancreatitis whereas CRP and PSTI did not. The elevation of PMN-E and IL-6 was greater the more severe the symptoms. However, no significant correlation was observed between the number of organs damaged and the maximum serum concentrations of P-AMY and E-1, or the WBC count, which have been considered to be markers of pancreatitis. These results suggest that PMN-E and IL-6 concentrations are useful indicators of severity and prognosis and their determination facilitates the selection of appropriate treatment in the early stages of disease to prevent the aggressive progression of acute pancreatitis.  相似文献   
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