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11.
A 59 year old man with cirrhosis presented with encephalopathy and hyper-ammonaemia. T1 weighted magnetic resonance imaging demonstrated a large void tubular structure connecting the right posterior portal vein branch and the inferior vena cava through the right hepatic lobe inferiorly, and cine-mode imaging showed a flow within this channel. Clearly in this patient a significant portion of the portal venous blood was being shunted into the inferior vena cava, causing encephalopathy. The exact origin of this channel is not known, but several possibilities are discussed. It is also predicted that similar previously unknown large intrahepatic shunts will be discovered increasingly with the availability of modern imaging techniques.  相似文献   
12.
This study, aimed at elucidating the epidemiological features of primary liver carcinoma developing in non-cirrhotic livers, was based on 25,103 autopsies performed between 1975 and 1984 in Trieste, Italy. These autopsies correspond to approximately 70% of all deaths that occurred in this area. Various factors allegedly related to carcinomas were analysed in reference to our previous study on cirrhotic livers and in comparison with 5,603 autopsies in Kurume, Japan. There were 28 cases of hepatocellular carcinoma (HCC), 16 of cholangiocellular carcinoma (CCC) not associated with cirrhosis in Trieste, and 48 HCC and 19 CCC in Kurume. On the basis of our findings, it was concluded that cirrhosis, regardless of its cause, is the main pathogenetic factor in HCC; it is responsible for a much higher frequency (14.2:1) than in non-cirrhotic livers, as well as for early occurrence of tumours (an average of 6 years earlier in cirrhotic liver) in Trieste. Patients in Trieste were older than those in Japan, and the frequency of HCC among all autopsies was much greater in the latter. By contrast, the influence of cirrhosis on cholangiocellular carcinoma (CCC) was negligible, as such association appeared purely coincidental or absent. The incidence of CCC among autopsies was greater in Japan. Our data on CCC were not sufficient to demonstrate any clear aetiopathogenetic association between this tumour and alcohol abuse and hepatitis B virus (HBV) infection, except for a possible aetiological role of gallstones. The frequency of CCC relative to HCC was greater in Trieste than in Japan; the incidence of HCC was much less in Trieste, whereas CCC was more frequent in Japan.  相似文献   
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14.
Proliferating cell nuclear antigen (PCNA), also known as cyclin, is an auxiliary protein of DNA polymerase-δ and is found only in the nuclei of proliferating cells in the late G1 and S phases. The proliferation of hepatocellular carcinoma (HCC) by immunohistochemical staining for PCNA using paraffin sections of 20 surgically resected HCC specimens was analysed. The mean percentage of PCNA-positive nuclei in the HCC tissue was 10.3% in grade I of Edmondson and Steiner's classification, 25.5% in grade II, 28.4% in grade III and 41.5% in grade IV. In early HCC, we observed only a few PCNA-positive tumour cells. However, PCNA-positive nuclei were numerous in the tumour thrombi found in portal vein branches, in regions of extracapsular tumour growth, and in the inner nodules of tumours with a nodule-in-nodule formation. Proliferating cell nuclear antigen positivity was correlated with an increase of the nucleocytoplasmic ratio of tumour cells as determined by image analysis. Our findings showed that PCNA positivity was correlated with the histological grade and invasiveness of HCC, suggesting that this antigen may be used as an indicator to predict tumour invasion in patients with HCC.  相似文献   
15.
Summary: Mesangial cell growth stimulation by endothelin (ET) and arginine vasopressin (AVP) has been reported, but only in studies using late (3 times) pasaged cells. In the present study, we examined the effects of ET, AVP and platelet activating factor (PAF) on the proliferation of early (<3 times) passaged cultured rat mesangial cells which maintained their original characteristics. Cell growth was estimated by [3H]-thymidine incorporation into DNA and by counting cell nuclei. After 48 h preincubation in minimal essential medium containing 0.5% fetal calf serum, ET-1 (1-100 nmol/L), AVP (100 pmol/L-1 μmol/L) or PAF (1–100 nmol/L) was added to the incubation medium. In contrast to studies using late passaged cells, ET-1 attenuated and AVP did not increase thymidine uptake (ET-1: 18.4% inhibition at 10 nmol/L) or cell counts in early passaged cells, while the growth stimulatory effects of these agents were reproduced in late passaged cells. Platelet activating factor showed definite stimulation of cell growth in both early and late passaged cells in a dose-dependent manner. These data strongly suggest that ET-1 attenuates, and AVP does not stimulate, the cell growth of original mesangial cells. the PAF-induced cell growth seems to be the constant feature of mesangial cells in vivo.  相似文献   
16.
Abstract A total of 184 cases of extrahepatic portal obstruction (EHPO), mostly demonstrated by intraoperative portography and studied at 17 institutes during the period 1957–1983, were compared with 469 cases of idiopathic portal hypertension (IPH) similarly studied. Of the cases of EHPO, there were 101 males and 83 females; 93 were under 20 years of age and the average age was 25.9 years (i.e. much younger than that of IPH cases). There were two age peaks, one before age 19 years and the other at age 40–49 years. One out of three adult cases had a history of abdominal surgery, but otherwise the aetiologic factor was difficult to elicit. Bleeding was the initial symptom in the majority, and splenectomy and haematological findings of hypersplenism were less pronounced compared with IPH. Liver function tests were almost always normal. The liver appeared normal macroscopically in 69% and histologically in 35%. The changes seen in the remainder were similar to those in IPH; they were less frequent in young patients than in cases above age 20 years. Compared with IPH, the wedged hepatic venous pressure in patients with EHPO was lower and the gradient from the portal venous pressure was greater. It is concluded that extrahepatic portal obstruction is less common compared with IPH in Japan, and that there are cases particularly among adults that present clinicopathological features very similar to those of IPH. It is unclear at present whether these two disorders represent two different disease entities, or whether they represent one disorder with differences in the site of involvement along the portal vein system.  相似文献   
17.
Abstract The influence of alcohol (ethanol) on sleep was investigated in 10 men. Polysomnography (PS) was recorded on a baseline night (BL-N) and an ethanol (0.8 g/kg) night (Et-N). On visual score rapid eye movement (REM) sleep was reduced, REM latency was prolonged on Et-N as compared to BL-N. Using the fast Fourier transformation method, electroencephalographic power density of REM sleep in δ frequencies band and in the 10–12 Hz range of non-REM sleep were enhanced. REM sleep and non-RJEM sleep changes were prominent in the second-half and first-half of the night, respectively.  相似文献   
18.
A single oral dose of 150 mg levamisole was administered to five healthy adults. Circulating Fc(IgG) receptor-bearing T cells (T gamma cells) increased for 5 days after levamisole intake, but total E rosette-forming cells showed no significant alterations. The generation of immunoglobulin-producing cells in the peripheral blood lymphocytes (PBL), which was induced in the in vitro pokeweed mitogen (PWM)-stimulated cultures, was significantly suppressed for 5 days after levamisole administration. Suppressor T-cell activity on B-cell differentiation, which was induced by levamisole intake, was evaluated by co-culturing with allogeneic untreated adult PBL in the PWM system in six other volunteers. A seemingly dose-dependent suppression on B-cell differentiation was exerted by T cells isolated on day 3 of levamisole treatment, but not by T cells differentiation was exerted by T cells isolated on day 3 of levamisole treatment, but not by T cells which were isolated before or on day 14 of the experiment. When T cells were fractionated into two subsets with regard to the presence or absence of Fc(IgG) receptors, suppressor T-cell activity appeared to be generated by levamisole largely in T cells lacking Fc(IgG) receptors, but not in T gamma cells.  相似文献   
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20.
Multiple gastric carcinoma was endoscopically diagnosed in 14 patients (13.6%) with 33 lesions (27.3%), out of 103 cases of early gastric carcinoma treated by endoscopic surgery. The sex ratio of these patients was 11 males to 3 females, and their mean age was 61.7 years old. In 79% of the patients the macroscopic type of the lesions was the same. Twelve of 33 lesions were metachronous lesions diagnosed by endoscopy using the dye contrast method. All of the metachronous lesions were evaluated as invading only as far as the mucosa. Almost all of the metachronous lesions were located at a height similar to that of the initial lesion or in a more oral direction. Eleven of 12 metachronous lesions were less than 2 cm in diameter, including 5 minute cancer lesions which were less than 5 mm in size. All these lesions were treated again endoscopically without gastrectomy. These results suggest that an annual endoscopy using the dye contrast method permits early detection of gastric carcinoma at a stage at which it can be treated endoscopically.  相似文献   
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