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81.
A 60-year-old woman was admitted to our hospital in February 1993 due to dizziness, dyspnea, abdominal pain, and high susceptibility to bleeding. Physical examination revealed livedo reticularis of the foot, but did not detect hepatosplenomegaly. Examination of the peripheral blood detected pancytopenia, leukoerythroblastosis, and tear-drop erythrocytes. Primary myelofibrosis (PMF) was diagnosed on the basis of bone marrow biopsy findings. Antiphospholipid syndrome (APS) was confirmed by positive response to anti-cardiolipin antibody and recurrent splenic infarction. Because of factor XIII deficiency, the patient experienced severe gingival bleeding after tooth extraction. Her condition was complicated by mesenteric arterial thromboembolism and she died of sepsis 5 years after onset. Although the incidence of immunopathy in PMF patients is high, few studies to date have focused on APS patients presenting with a variety of severe embolic symptoms. Our patient required careful monitoring due to bleeding tendency and thromboemboli.  相似文献   
82.
Dysregulation of apoptosis or programmed cell death is a hallmark of human cancers that contributes to tumor development and progression, and may confer treatment resistance and therapeutic failure. Apoptosis is governed by both a mitochondria-mediated and a death receptor (DR)-mediated pathway. Within human cancer cells, both apoptotic pathways are regulated by proapoptotic and prosurvival Bcl-2 family proteins. Loss of proapoptotic genes or, alternatively, upregulation of prosurvival genes may lead to tumorigenesis in preclinical models. Expression of Bcl-2 family proteins has been shown to provide prognostic information in certain malignancies, including colon cancers, and therefore may be useful in determining which patients are more likely to suffer recurrence and metastasis. Such markers may assist in selecting patients to receive adjuvant chemotherapy and represent potential targets for therapeutic intervention. In the therapeutic arena, small molecule Bcl-2/Bcl-xL antagonists and DR agonists have been developed that enhance chemosensitivity in preclinical models and currently are undergoing evaluation in cancer patients. This review focuses on the current status of apoptotic regulatory proteins as biomarkers in colorectal cancers and their potential clinical utility.  相似文献   
83.
Equine piroplasms in Greece were studied using the reverse line blot hybridization (RLB) assay. Three genotypes consisting of two Theileria (T. equi and T. equi-like) and one Babesia (B. caballi-like) were identified. Of 787 samples tested, 371 (47.14%) hybridised to catchall probe (probe specifically designed to capture any piroplasm species present in a sample), 346 (43.96%) to T. equi probe, 364 (46.25%) to T. equi-like probe, 0 (0%) to B. caballi probe and 3 (0.38%) to B. caballi-like probe. Seven samples gave faint signals with the catchall probe only, indicating the presence of known or unknown piroplasm species, or a novel genotype or a known genotype occurring at a very low level of parasitemia. A partial sequence (509 bp) of the V4 region of the 18S rRNA gene of a T. equi-like isolate showed only 99% similarity with the reference T. equi-like isolates from Northern Spain from which the detecting probe used in the present study was designed but showed 100% similarity with the T. equi-like variants from Southern Spain. This indicated a noticeable degree of polymorphism within the population of T. equi-like. No unusual parasites previously reported in horses, such as B. canis canis and B. bovis were detected in this study. The values of the bioclimatic variables were very similar between the geographic locations for T. equi and T. equi-like genotypes, suggesting the two are not yet different species as hypothesized by some authors but are possibly undergoing a speciation process within Theileria genotypes. Both T. equi and T. equi-like were found in predominantly forest type land cover.  相似文献   
84.
The contribution of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a death ligand expressed by cells of the innate immune system, to cholestatic liver injury has not been explored. Our aim was to ascertain if TRAIL contributes to liver injury in the bile duct-ligated (BDL) mouse. C57/BL6 wild-type (wt), TRAIL heterozygote (TRAIL(+/-)), and TRAIL knockout (TRAIL(-/-)) mice were used for these studies. Liver injury and fibrosis were examined 7 and 14 days after BDL, respectively. Hepatic TRAIL messenger RNA (mRNA) was 6-fold greater in BDL animals versus sham-operated wt animals (P < 0.01). The increased hepatic TRAIL expression was accompanied by an increase in liver accumulation of natural killer 1.1 (NK 1.1)-positive NK and natural killer T (NKT) cells, the predominant cell types expressing TRAIL. Depletion of NK 1.1-positive cells reduced hepatic TRAIL mRNA expression and serum alanine aminotransferase (ALT) values. Consistent with a role for NK/NKT cells in this model of liver injury, stress ligands necessary for their recognition of target cells were also up-regulated in hepatocytes following BDL. Compared to sham-operated wt mice, BDL mice displayed a 13-fold increase in terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and an 11-fold increase in caspase 3/7-positive hepatocytes (P < 0.01). The number of TUNEL and caspase 3/7-positive cells was reduced by >80% in BDL TRAIL knockout animals (P < 0.05). Likewise, liver histology, number of bile infarcts, serum ALT values, hepatic fibrosis, and animal survival were also improved in BDL TRAIL(-/-) animals as compared to wt animals. Conclusion: These observations support a pivotal role for TRAIL in cholestatic liver injury mediated by NK 1.1-positive NK/NKT cells.  相似文献   
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86.
A 46-year-old woman was diagnosed as having acute myeloid leukemia (M 1) with translocation t(16;21) (p11;q22). The leukemic cells were positive for CD 13, CD 33, CD 34, CD 41, CD 56 and HLA-DR. After induction chemotherapy, the patient achieved complete remission (CR). However, 8 months later she relapsed with various additional chromosomal abnormalities. Although the patient achieved a 2nd CR after re-induction chemotherapy, the patient had extramedullary tumors in the right breast twice and relapse occurred frequently. The tumor cells were characterized by the same immunophenotypes and t(16;21) with additional 1 q trisomy. Although there was no evidence of hematological relapse, another type of 1 q trisomy was observed. Furthermore, an increase of abnormalities with 1 q trisomy was noted concomitant with re-increase in the number of blasts. The patient underwent allogeneic bone marrow transplantation (BMT), but she died from BMT complications. The case could have been a karyotype of t(16;21) with additional chromosomal abnormalities through consecutive approaches. Because of the high occurrence rate of relapse, we consider various additional chromosomal abnormalities and the expression of CD 56 as prognostic factors of this condition.  相似文献   
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89.
The treatment of neuroma-in-continuity is controversial. To bypass neuroma-in-continuity with a nerve graft using end-to-side neurorrhaphy is considered to be theoretically a good option. To test this therapeutic modality, we performed a nerve bypass graft in a neuroma-in-continuity rat model. An obstructive neuroma-in-continuity was created in a transected peroneal nerve by interposition using the aponeurosis of the spinal muscles. In the experimental animals, (1) immediate, (2) 3-week delayed, or (3) no ulnar nerve bypass graft was performed. The peroneal functional index (PFI), conduction velocity, tibialis anterior muscle weight, and histomorphometric analyses were performed and compared with control (simply cut and repair) animals. On postoperative day 70, the recoveries of the PFI values, conduction velocity, and tibialis anterior muscle weight in the bypassed animals showed no significant differences as compared with the control animals, and the extent of these recoveries in the bypassed animals were significantly superior to those in the no-graft animals. In the histomorphometric analysis, the mean percent nerve in the bypassed animals was significantly larger than that in the no-graft animals. In conclusion, this technique may be a good alternative to the current therapeutic techniques for neuroma-in-continuity when there is a significant retained function.  相似文献   
90.
A new lignan glucoside (1) was isolated from the stems of Callicarpa japonica Thunb. var. luxurians Rehd. (Verbenaceae), along with six known lignan glucosides and three known triterpenoids. The chemical structure of 1 was characterized as (+)-lyoniresinol 3α-O-(6″-3,5-dimethoxy-4-hydroxybenzoyl)-β-d-glucopyranoside on the basis of spectroscopic data. In addition, the radical-scavenging effect of four lignans on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Among the tested compounds, three compounds, including 1, showed almost the same scavenging activity as that of α-tocopherol.  相似文献   
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