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81.
We conducted a placebo–controlled, randomized, and double–blinded study to evaluate the efficacy of manidipine given orally in attenuating the cardiovascular responses to laryngoscopy and tracheal intubation. Thirty normotensive patients (ASA physical status 1) undergoing elective surgery were allocated to one of three groups (n= 10 for each); placebo, 5 mg manidipine, and 10 mg manidipine groups. These tablets were orally administered 3 h before induction of anaesthesia. Anaesthesia was induced with thiopentone 5 mg kg-1 iv , and tracheal intubation was facilitated with vecuronium 0.2 mg–kg-1. Laryngoscopy lasting 30 sec was attempted 2 min after induction of anaesthesia. Patients receiving placebo showed a significant increase in systolic and diastolic blood pressure associated with tracheal intubation. These increases following tracheal intubation were significantly reduced in patients receiving manidipine 10 mg compared with patients receiving placebo or manidipine 5 mg ( P < 0.05). Oral administration of manidipine 10 mg before induction of anaesthesia is a simple and effective method for attenuating pressor response to laryngoscopy and tracheal intubation. We stressed that the potential beneficial effect of a reduced haemodynamic reaction to intubation might be obtained at the expense of hypotension later on.  相似文献   
82.
83.
Six primary adenocarcinomas were found among 1,346 cases ofesophageal carcinoma, an incidence of 0.45%. Three of the adenocarcinomaswere the "type ordinaire" of Lortat-Jacob, two were adenoidcystic carcinoma, and one was mucoepidermoid carcinoma. Theinitial symptom was dysphagia in all six cases. All six lesionswere located in the middle and/or lower third of the esophagus.Esophagograms showed tumorous-type lesions in four cases andspiral-type in two cases. Although endoscopical examinationwas performed in five cases, the biopsied specimen showed adenocarcinomasin only two. Four patients were operated and on two receivedradiation therapy. Four patients died within one year, and twoare still alive more than 21 months after surgery.  相似文献   
84.
To examine the expression of p53 protein and gene alterations in oral epithelial lesions including epithelial dysplasias and primary squamous cell carcinomas, immunohistochemical and temperature gradient gel electrophoresis (TGGE) methods were applied to formalin-fixed and paraffin-embedded tissues. Morphologically normal mucosal epithelium stained negatively for p53 protein. Three out of 11 (27·3 per cent) epithelial dysplasias and 19 out of 57 (33·3 per cent) primary squamous cell carcinomas stained positively for p53 protein. Although more than half of the cases were positive for p53 protein in stage I, the positive cancer cases were found at other stages with variable frequency. Immunoreactive products were localized in the nucleus, especially in the basal and suprabasal layers. The analysis by TGGE revealed gene alterations in exons 5–8 in 3 out of 3 epithelial dysplasias and 17 out of 19 (89·5 per cent) primary squamous cell carcinomas which were immunohistochemically positive for p53 protein. These results suggest that p53 gene mutation may be involved in carcinogenesis in the oral squamous epithelium even in the early stage of the dysplasia–carcinoma sequence.  相似文献   
85.
Hodgkin and Reed-Sternberg (H & RS) cells are generally considered to be the neoplastic cells of Hodgkin's disease (HD), however such cells are only found in a minority of the lesions. Recently in a few studies on HD, the clonality of H & RS cells was examined, using a single-cell polymerase chain reaction (PCR) examination. To clarify the lineage and clonality of H & RS cells, we performed single cell PCR and in situ hybridization (ISH), and nine cases of classical HD were thus studied. By ISH, the immunoglobulin J chain, and the |gk and |gl light chain were rarely expressed in the H & RS cells, however, no T-cell markers could be detected. The expression of the recombination activating genes (RAG-1, 2) could be determined in the H & RS cells. We isolated CD30+ H & RS cells, CD3+ T cells and CD20+ B cells from suspended materials using a mechanical sorter. We performed single cell PCR in a sorted individual cell, to amplify the complementarity determining region of the Ig heavy chain (IgH) gene and T-cell receptor γ chain (TCR γ) gene. In all cases, TCR γ could be frequently amplified in the T cells, but was only rarely amplified in the H & RS and B cells. In contrast, the IgH was frequently amplified in the H & RS and B cells, but not in the T cells. In addition, the PCR production of the H & RS cells all showed different lengths. The results therefore support the polyclonal nature and immature B lymphoid cell origin of H & RS cells.  相似文献   
86.
A simulation model was developed to better understand the mechanisms of brain injuries in sports. A three-dimensional model comprising approximately 1.22 million elements was constructed from cranial computed tomography images of adult male volunteers by the voxel method. To simulate contact sports that permit actions such as tackling, a sinusoidal wave with duration of 10 ms and maximum acceleration of 2000 m/s2 was applied to the lowest point of the model to apply rotational acceleration to the head from different directions. The von Mises stress was then observed at five points in the coronal plane of the brain: cingulate gyrus (CG), corpus callosum (CC), brain stem (BS), lateral temporal lobe (LT), and medial temporal lobe (MT). LS-DYNA universal finite element analysis software with explicit time integration was used for the analysis. Concentrations of stress started to appear in the CC and BS at 10 ms post-impact, after which they also became evident in the CG and MT. The maximum changes in stress at each location occurred 10–15 ms post-impact. The von Mises stress was 9–14 kPa in the CG, 8–24 kPa in the CC, 12–24 kPa in the BS, 7–12 kPa in the LT, and 12–18 kPa in the MT. The highest stress in every part of the brain occurred after lateral impact, followed by oblique impact and sagittal impact. Such simulations may help elucidate the mechanisms of brain injuries in sports and help develop measures to prevent chronic traumatic encephalopathy.  相似文献   
87.
ABSTRACT: A sperm antigen has been isolated front radiolabeled human sperm cell membrane by detergent solubilization, lectin affinity chromatography, gel filtration, and indirect immune precipitation using sperm-immobilizing antisera from patients with unexplained infertility. Isolated material was characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Among 20 infertile women's sera with sperm-immobilizing antibodies, two were found to react predominantly with a sperm membrane polypeptide having the approximate molecular weight of 15,000 daltons. No significant binding to this molecule was observed in any sera from pregnant women, unmarried women, and normal men. By the absorption with spermatozoa, the antisera lost their binding activity to the molecule, while the sera absorbed with seminal plasma did not lose the activity. The results indicated that the molecule is a genuine sperm antigen and not a sperm-coating seminal plasma antigen. By the indirect immunofluorescence of washed ejaculated spermatozoa with the antisera, strong fluorescence was localized only in an equatorial segment of the acrosome, while no specific staining was observed in the controls. The antigen is relatively unstable against acid, alkali, and heat treatment. Treatment with proteolytic enzymes such as pronase and trypsin inactivated the antigen activity, indicating that the antigen epitope could be a peptide portion of the glycoprotein.  相似文献   
88.
Currant histopathoiogical evidence suggests that gall-bladder cancer has two main morphological pathways for Its development: de novo ( ab Inltlo ) origin and adenoma-carcinoma sequence. In order to investigate the genetic difference between them, APC mutations were examined by RNase protection analysis, K-ras mutations by nested porymerase chain reaction-restriction fragment length polymorphism analysis, and p53 gene overexpression by immunoriisto-chemical analysis in both tumors and benign lesions of the gall-bladder. Overexpression of the p53 gene was detected in 105 of 164 (64%) de novo carcinomas regardless of size and depth of Invasion, but not in 16 tumors of carcinoma-ln-pyloric-gland-type adenoma, or In 51 adenomas (47 pyloric gland-type and 4 Intestinal-type). K-ras codon 12 mutation was detected in 4 of 40 (10%) de novo carcinomas, ail four being associated with p53 gene overexpression, but not in 12 tumors of carcinoma in adenoma or 16 adenomas (14 pyloric gland-type and 2 intestinal-type). APC mutation was not found in 16 de novo carcinomas or the one pyloric gland-type adenoma examined. These results suggest that there are two distinct genetic pathways in gall-bladder carcinogenesis; that is, de novo carcinoma develops from a predominant p53 alteration with low K-ras mutation, and carclnoma-in-pylortc-gland-type adenoma develops from p53 -, K-ras -, and APC -gene-unrelated, as yet unknown, alteration.  相似文献   
89.
Background: The aim of this study was to clarify the clinical significance of reddish markings appearing on the surface of the liver. Methods: Subjects were patients with Hepatitis B virus‐related (n = 232) or Hepatitis C‐related (n = 246) chronic liver disease. Reddish lesions were obtained from this population using punch biopsy (n = 30) or wedge biopsy (n = 4), then studied histopathologically. In addition, the incidence and macroscopic forms of reddish markings in each laparoscopic stage for the 478 subjects were examined to determine when reddish markings appeared. Results: Reddish markings on the liver surface appeared only after the appearance of hepatic parenchymal destruction subjacent to the liver capsule, rather than with the appearance of piecemeal necrosis in the portal area. Moreover, following expansion of necrotic hepatic parenchyma subjacent to the liver capsule and distortion of hepatic lobular architecture in this lesion, net‐like or hemorrhagic fleck‐like reddish markings appeared. Therefore, this was recognized as changes at the liver capsule, such as capillary proliferation and dilatation, and blood flow changes in both the capsule and hepatic parenchymal lesions subjacent to the liver capsule. With regards to timing, reddish markings were most frequently observed in the transition to liver cirrhosis. After the appearance of reddish markings on the liver surface, chronic hepatitis rapidly progressed to liver cirrhosis. Conclusion: Reddish markings correspond to hepatic parenchymal destruction subjacent to the liver capsule, and not to piecemeal necrosis. Reddish markings appear in the transition to liver cirrhosis and might offer a useful marker of the progression to liver cirrhosis.  相似文献   
90.
A 79‐year‐old man who had received radiotherapy for portal vein thrombosis due to hepatocellular carcinoma (HCC) 5 months earlier, showed progressive anemia and melena. Endoscopy on admission revealed diffuse bleeding from multiple telangiectasias on the anterior wall of the antrum and bulbus. We treated this patient with a new non‐contact hemostatic method: the argon plasma coagulator (APC). The melena stopped after the first session and the hemoglobin level remained stable for 7 months. No delayed complications have been observed. Gastrointestinal bleeding from chronic radiation gastroduodenitis is rarely reported compared with radiation proctitis. This case demonstrates that APC is effective for hemostasis of diffuse bleeding from radiation gastroduodenitis, just as for radiation proctitis.  相似文献   
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