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81.
Electrocorticography of the primary motor cortex (M1) is a promising tool for controlling a brain–computer interface (BCI). Electrocorticograms (ECoG) of the human M1 within the central sulcus (intrasulcal ECoG) have been rarely examined. In order to evaluate the usefulness of intrasulcal ECoG for BCI, we examined patients with subdural electrodes placed temporarily inside the central sulcus and over the sensorimotor cortex (gyral ECoG). Five patients were asked to perform or imagine two or three classes of simple upper limb movements. Univariate statistical analysis of the results revealed that the intrasulcal ECoG on M1 showed significant variability across movement classes. A support vector machine was used for classification of single-trial ECoG signals to infer movement class (neural decoding). The movement classes were predicted with 80–90% accuracy (chance level: 33% or 50%). To reveal the relative importance of anatomical areas for neural decoding, the decoding performance was compared between gyral and intrasulcal ECoGs. The intrasulcal ECoG on the motor bank showed higher performance than the equally-sized gyral ECoG or the intrasulcal ECoG on the sensory bank. Analysis using a short time window revealed that movement class could be decoded even before movement onset. These results suggest the usefulness of intrasulcal ECoG on M1 to infer upper limb movements and present a promising application for a practical BCI system.  相似文献   
82.
A 71-year-old Japanese male with myelodysplastic syndrome progressing to overt leukaemia and hepatocellular carcinoma developed dyspnea and urticaria immediately after infusion of platelet concentrate (PC). He exhibited an identical reaction following blood transfusion. Serum haptoglobin was undetectable. The patient was determined to be homozygous for Hp(del) by polymerase chain reaction (PCR). Antibody to haptoglobin was detected by enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. No antibodies against human leucocyte antigen (HLA) or platelet-specific antigens were detected. Washed PC and washed red blood cells were effective in preventing the transfusion-related anaphylactoid reactions.  相似文献   
83.
84.
The specificities and surface markers of murine autocytotoxic cells induced by in vitro culture with interleukin 2 (IL2) were studied. Culturing murine spleen cells with recombinant human IL2 resulted in the generation of cytotoxic cells which killed syngeneic lymphoblasts and syngeneic activated macrophages (M phi). Both lectins and protein antigens were capable of inducing lymphoblasts recognized by lymphokine-activated killer (LAK) cells. B-lymphoblasts as well as T-lymphoblasts were sensitive to lysis by these effector cells. In addition, peritoneal M phi activated in vivo with Bacille Calmette-Guérin (BCB), Corynebacterium parvum (C. parvum), thioglycollate (TG) or lipopolysaccharide (LPS) were shown to be susceptible to lysis by LAK cells. In contrast, neither unstimulated T cells nor resident peritoneal M phi were sensitive to lysis by LAK cells, suggesting that normal cells have to be activated in order to be sensitive to lysis by these effector cells. Surface marker analysis indicated that majority of effector cells which killed syngeneic lymphoblasts and activated M phi were Thy1+, asialo GM1+, L3T4-, Ly2-.  相似文献   
85.
A new clinical grading of subarachnoid hemorrhage (SAH) due to ruptured aneurysm, classified by the presence or absence of vomiting, and by the duration of initial unconciousness at the time of bleeding, is proposed. Grade I: headache without vomiting, Grade II: headache, vomiting, and/or loss of consciousness lasting less than one hour, Grade III: loss of consciouness for over one hour. Grade IV: permanent unconsciousness or cerebral herniation signs. Based on the clinical records, 142 cases of ruptured cerebral aneurysms directly operated on in phases varying from peracute phase (within 72 hours) to delayed phase (22 days or over) were retrospectively analyzed. They included 99 cases which were operated on under microscope. The Hunt & Hess grading was applied just before surgery. Outcome at the 6 month to 1 year follow-up was rated as good, fair, poor and dead. Correlations between the severity and the outcome were calculated using the chi-square test and the levels of significance were compared with those between the recent Hunt and Hess grading and the outcome. In the total of 142 cases, correlation between the clinical severity and the outcome was significant (P less than 0.0005), whereas correlation between the Hunt & Hess grading and the outcome was not significant. In the analysis of cases classified by the operative timing, the clinical severity showed good correlation in the peracute (within 72 hours after SAH) (P less than 0.05) alone, while Hunt & Hess grading showed correlation in delayed phase alone. Neither of the gradings was significant in the acute phase or subacute phase.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
86.
Four mixed oligodendrogliomas and astrocytomas were investigated by electron microscopy and immunohistochemistry (GFAP, NSE and MBP). GFAP-positive oligodendroglioma cells and their transitional cells to GFAP-negative oligodendroglioma cells were present, suggesting successive morphological changes of astrocytic tumor cells. NSE-positive cells, suggestive of residual neurons, also exhibited round nuclei and perinuclear halos. On electron microscopy, oligodendroglioma cells that showed glial filaments, vascular end-feet and zonulae adherentes were occasionally present. The tumor cells with or without astrocytic characteristics showed common features of cytoplasmic organelles. These findings suggest that most oligodendroglioma cells in mixed gliomas are of an astrocytic nature and that characteristic microscopic features of oligodendroglioma are of a common cellular form that can be taken by various types of cells under certain circumstances.  相似文献   
87.
The two cell lines, TTK-1 (E) and TTK-1 (F), were established from normal human decidual tissue of early gestation. The primary culture was initiated by a fragment culture technique in July, 1979 and the cultures were passaged about once every two months. Meanwhile two kinds of the cultures, the epithelial-like cell dominant one and the fibroblast-like cell dominant one, had appeared. The former has been subcultivated and maintained at a constant growth rate and designated as the TTK-1 (E) cell line. The latter showed a gradual decline in growth rate and finally growth ceased at 3 years after the initiation of the culture. The sudden onset of growth and colony formation occurred after 4 months of senescence and the fibroblast-like cell culture has been maintained at a constant growth rate and designated as TTK-1 (F) cell line. Morphological studies revealed that the TTK-1 (E) cell line had epithelial-like characteristics and TTK-1 (F) cell line had fibroblast-like features. Both cell lines showed heteroploid karyotypes and tumorigenicity in nude mice transplantation. The two cell lines appeared to be established by spontaneous neoplastic transformations and should be useful cellular models for the study of malignant endometrial tumors.  相似文献   
88.
Parapapillary choledochoduodenal fistula is a rare disorder. We herein report a case of parapapillary choledochoduodenal fistula associated with cholangiocarcinoma. A 61‐year‐old woman was admitted to our hospital for further examination of a liver tumor. She had no clinical symptoms, but computed tomography scans showed an irregularly contoured liver tumor which was histologically confirmed to be adenocarcinoma, by a needle biopsy examination. Duodenal fiberscopy revealed a fistula orifice 1.0 cm proximal to the orifice of the papilla of Vater, and endoscopic retrograde cholangiography through the fistula showed a communication to the common bile duct. Hypotonic duodenography demonstrated reflux of contrast material into the choledochoduodenal fistula. The bile sample collected from the common bile duct showed extremely high levels of pancreatic enzymes, including amylase, phospholipase‐A2, and elastase‐I. Furthermore, Helicobacter DNA was detected in bile by polymerase chain reaction (PCR) analysis. This experience suggests to us that parapapillary choledochoduodenal fistula may be a risk factor for biliary tract carcinoma, and surgical management is the treatment of choice for this rare condition, even when the patient has no significant clinical symptoms.  相似文献   
89.
Synthesis and activity of the enzymatic equivalent of the sodium pump, Na,K-ATPase, are regulated by thyroid hormone in responsive tissues. The purpose of this study was to determine whether triiodothyronine (T3) regulates the level of the messenger RNA (mRNA) coding for Na,K-ATPase alpha- and beta-subunits in the heart. The expression of Na,K-ATPase mRNAs in in vitro myocardial cells was directly assayed by Northern and slot blot hybridization using Na,K-ATPase alpha- and beta-isoform-specific cDNA probes. Exposure of cultured neonatal rat cardiocytes to 10(-8) M T3 resulted in 1) threefold to fourfold increase in alpha 1- and beta 1-mRNA accumulation, with a maximum elevation at 48 hours, 2) sevenfold increase in alpha 2-mRNA accumulation with a peak elevation at 72 hours, and 3) transient threefold increase in alpha 3-mRNA within the first 24 hours followed by a deinduction thereafter. The increase in alpha 1-mRNA accumulation by T3 occurred over the physiological T3 concentration range with an EC50 of 5 x 10(-10) M. This was associated with a twofold increase in alpha 1-subunit protein accumulation and an increase in Na,K-ATPase transport activity. The half-life of alpha 1-mRNA analyzed by actinomycin D chase was less than 3 hours and was not affected by T3. Transfection experiments with the luciferase reporter gene revealed that thyroid hormone response sequences are located within the 5'-flanking regions of each alpha-isoform gene.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
90.
Revision surgery for lumbar disc herniation   总被引:1,自引:0,他引:1  
Summary We reviewed 45 patients who had undergone repeated open operations for lumbar disc herniation. There were 26 men and 19 women with a mean follow up of 4.3 years. Twenty-four patients had had one previous discectomy, 12 had 2, and 9 had 3 or more; 11 needed a fusion without instrumentation. Residual or re-extruded disc hernias, either sub- or transligamentous, were frequently found at revision. Good to excellent results were obtained in 64%. Those who had a first-time revision had earlier improvement and better results. Complete removal and a thorough search for herniated disc material is essential when carrying out the initial operation for extruded or sequestrated herniation. At revision, removal of as much as possible of the remaining nucleus and annulus, but with minimal invasion of the posterior elements, is crucial for improving the outcome.
Résumé Notre étude porte sur 45 patients ayant subi à plusieurs reprises une discectomie lombaire. Ce groupe était composé de 26 hommes et de 19 femmes suivis pendant 4,3 ans en moyenne (de 1 à 8 ans). Vingt-quatre patients avaient déjà été opérés une fois, 12 deux fois et 9 trois fois ou plus. Une arthrodèse était indiquée dans 11 cas. Les réinterventions ont montré que des hernies résiduelles ou ré-expulsées, sous-ligamentaires ou trans-ligamentaires, étaient souvent retrouvées. 64% (29/45) des patients ont eu de bons ou d'excellents résultats. Les patients n'ayant subi qu'une seule réintervention se sont rétablis plus rapidement et ont présenté de meilleurs résultats. Nous tenons à souligner qu'il est essentiel de procéder à l'ablation complète et à la recherche méticuleuse de tous les matériaux discaux herniés lors de la première intervention, en particulier pour les hernies expulsées ou séquestrées. En cas de réintervention il convient d'enlever autant d'anneau et de noyau résiduel que possible, quoique plus modérément en arrière, pour obtenir les meilleurs résultats.
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