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991.
A 82-year-old woman was referred to our department for further evaluation of her atelectasis in the left lower lobe of the lung which was found under preoperative examination for a renal pelvic tumor resection. Bronchoscopic examination was performed, and a pin-hole stenosis at the orifice of the left main bronchus was detected. Tuberculous bronchial stenosis was suspected because she had pulmonary and laryngeal tuberculosis 50 years ago. The dilatation of the stenosis was supposed to be necessary in order to prevent a pulmonary complication during the perioperative period. The stenotic area was dilated using argon plasma coagulation. Eight weeks after the procedure, a bronchoscope 6mm in external diameter could pass the dilated area. We reported a rare case with tuberculous bronchial stenosis in which the patient had never experienced a severe complication for 50 years despite the pin-hole stenosis in the left main bronchus.  相似文献   
992.
Prognostic factors, including clinical, biological, and histological parameters, were assessed for 94 patients with follicular lymphomas at our institute. Follicular lymphomas constituted 7.7% (94/1208) of malignant lymphomas in this study. Eighteen patients were diagnosed with stage I follicular lymphoma, 20 with stage II, 23 with stage III, and 33 with stage IV. The cases of follicular lymphoma were subclassified as: follicular small cleaved cell lymphoma (FSC) in 20 cases, follicular mixed cell lymphoma (FMX) in 59 cases, and follicular large cell lymphoma (FLC) in 15 cases. The patients comprised 49 men and 45 women with a median age of 54 years (range, 25-84 years). The complete response rate was 76.5%, and the median survival time was 13 years. The expected 10-year overall survival and event-free survival rates were 61.9% and 38.2%, respectively. Univariate analysis identified the factors associated with poor survival as elevated serum lactate dehydrogenase (LDH) level (P < .0001), age of >60 (P < .0001), Ann Arbor stage III/IV (P < .01), and Eastern Cooperative Oncology Group performance status (PS) of 2 to 4 (P = .048). Multivariate analysis showed that LDH, age, and PS were independent predictors. After application of the International Prognostic Index (IPI), the 10-year survival rates for the low-risk, low-intermediate risk, high-intermediate risk and high-risk groups were 80.4%, 48.7%, 21.9%, and 0.0%, respectively. The differences among these groups were significant at P < .01. The IPI for aggressive non-Hodgkin's lymphoma was found to be applicable to survival prediction for Japanese follicular lymphoma patients.  相似文献   
993.
We assessed the in vitro chemosensitivity of acute erythroblastic and megakaryoblastic leukemia cells from children with Down syndrome (DS) compared to non-DS children. We conducted in vitro tests using the MTT assay of bone marrow samples from 12 children with DS and 16 children without DS. Patients were newly diagnosed based on the morphology and expression of platelet-specific antigens. Induction failure occurred more frequently in the non-DS group (n = 4) than in the DS group (n = 0, P = .053). Children with DS had a superior event-free survival (EFS) probability of 0.750 at 4 years, compared to an EFS probability of 0.375 for non-DS children (P = .049). Blast cells from DS patients were significantly more sensitive to daunorubicin, melphalan, mitoxantrone, 4-hydroperoxy-cyclophosphamide, vincristine, etoposide, bleomycin, and pirarubicin than those from non-DS patients. Four of the 16 non-DS patients were found to have acquired an extra chromosome 21 in their leukemia cells: blasts from these patients also tended to have greater chemosensitivity than those from patients without an extra chromosome 21. Blast cells from DS patients are markedly sensitive to various drugs. These results suggest that the fragility of blast cells derived from DS patients may be related to an increased susceptibility to apoptosis.  相似文献   
994.
The emergence of immunoglobulin depositions in muscular vessels from patients with IgA nephropathy was examined to determine whether the pathogenesis of IgA nephropathy was mediated by circulating IgA-dominant immune-complexes. Muscle biopsy specimens were obtained from the right flank at the same time of modified open renal biopsy. These biopsy samples were stained with fluorescein-conjugated anti human IgG, IgA, IgM, IgE, and C3 antisera It was demonstrated that the depositions of IgA and/or C3 were observed in muscular vessels from some patients with IgA nephropathy. It is indicated that IgA nephropathy might be mediated by circulating IgA-dominant immune-complexes.  相似文献   
995.
CD27 is a marker of memory B cells and its interaction with its ligand, CD70, is very important for differentiation into plasma cells. Although CD27 is detected on normal plasma cells, its expression is significantly reduced with the progression of multiple myeloma (MM), including monoclonal gammopathy of undetermined significance (MGUS). CD27+ myeloma cells are thought to represent an early phase of myeloma, as CD27+ plasma cells from MM patients were found to be composed of normal plasma cells (CD19+/CD38++) and myeloma cells (CD19-/CD38++), and monoclonality was detected in the CD27+/CD38++ fraction. Given that the lack of CD27 on plasma cells is related to myelomagenesis and that the pro-apoptotic protein Siva is thought to bind to the cytoplasmic tail of CD27, we analysed alterations of cell growth and genes caused by co-culturing CD27-transfected myeloma cell lines (U266, KMS-5) with CD70-transfected NIH3T3 cells. CD27-CD70 interaction could not induce apoptosis in either type of myeloma transfectant, and binding between Siva and CD27 was not detected. cDNA microarray (human apoptosis CHIP) analysis showed a significant upregulation of expression of the ectodermal neural cortex 1 (ENC1) gene by CD27-CD70 interaction compared with CD27 transfection alone. These findings show that the relationship between the loss of CD27 and oncogenesis of plasma cells is not simple. It remains unclear whether the lack of CD27 leads to evasion of apoptosis.  相似文献   
996.
Refractoriness to platelet transfusion indicates a condition in which an expected increase in platelet count is not attained after platelet transfusion. We report herein two cases of refractoriness to platelet transfusion that were caused by the presence of antibodies against the human leukocyte antigen following partial hepatectomy for hepatocellular carcinoma. Due to low postoperative platelet counts in the first case, the patient was transfused with 75 units of platelet concentrate for 3 days after surgery, but was unable to gain a significant increase in the platelet count because of platelet transfusion refractoriness due to anti-human leukocyte antigen antibodies. This case was not complicated and had a favorable clinical course. Despite being transfused with 60 units of platelet concentrate during the 2 days after surgery, the patient's platelet count in the second case did not increase because of the presence of anti-human leukocyte antigen antibodies. Bleeding from the cut surface of the liver into the intraperitoneal cavity was found on the second postoperative day because of a decrease in platelet count. On postoperative day 5, disseminated intravascular coagulation occurred. Perioperative refractoriness to platelet transfusion is an intractable complication since no efficient treatment is available. Preoperative examinations for anti-platelet antibodies should be performed in patients undergoing hepatectomy for hepatocellular carcinoma. This is especially true in cases of decreased platelet counts due to preceding liver cirrhosis and when the prediction for postoperative platelet transfusions is necessary.  相似文献   
997.
OBJECTIVE: The high incidence of acquired drug resistance to STI571 during treatment of chronic myelogenous leukemia (CML) patients in blast crisis has become a problem. We studied the effects of interferon-alpha (IFN-alpha) on a novel STI571-resistant CML cell line and its molecular mechanisms in vitro. MATERIALS AND METHODS: KT-1 is a unique CML cell line that remains sensitive to the therapeutic IFN-alpha concentration. We developed novel STI571-resistant KT-1 cells (designated KTR cells) by gradually increasing the concentration of STI571. RESULTS: All seven KTR clones became more sensitive to IFN-alpha than KT-1 cells. IFN-alpha induced more prolonged phosphorylation of Stat1 for 24 hours in all seven KTR clones than in KT-1cells. Tyrosine phosphorylation of Jak1 in KTR cells was not prolonged compared to KT-1cells. T-cell protein tyrosine phosphatase (TC-PTP) was down-regulated in all KTR clones, and SH-PTP1 phosphatase also was down-regulated in some KTR clones. The transient transduction of TC-PTP cDNA into the KTR subline prevented the IFN-alpha-induced prolonged phosphorylation of Stat1 and recovered the sensitivity against IFN-alpha. These results indicated that the loss of TC-PTP is involved in the IFN-alpha-induced prolonged phosphorylation of Stat1 and in the higher sensitivity to IFN-alpha in KTR cells. CONCLUSION: We demonstrated that STI571-resistance does not confer cross-resistance to IFN-alphain KT-1 cells. The loss of TC-PTP contributed to the IFN-alpha-induced prolonged phosphorylation of Stat1 and the higher sensitivity to IFN-alpha in KTR cells.  相似文献   
998.
BACKGROUND/AIMS: Endoscopic papillary balloon dilation is an effective procedure in the management of bile duct stones and is believed to preserve the papillary function. The papillary architecture is also considered to be preserved. However, little is known about the effects of balloon dilation on papillary structure. The present study was conducted to elucidate these effects. METHODOLOGY: Since May 1994, endoscopic papillary balloon dilation was performed in 467 patients (407 patients for removal of bile duct stone, 57 for insertion of stent and 3 for baby cholangioscope). Of those, histological examinations were undertaken in 10 patients. The indications of endoscopic papillary balloon dilation were bile duct stone removal in 2 patients, stent insertion in 8. The specimens were obtained 2 to 63 weeks after endoscopic papillary balloon dilation during surgical operation in 6 patients and autopsy in 4 patients. Serial sections through the papilla were stained by hematoxylin and eosin and Masson's trichrome. The specimens were also obtained from 4 patients without biliary disease as control. RESULTS: No smooth muscle disruption nor architectural distortion was observed except for one patient who had mild disruption of smooth muscle caused by a biliary drainage tube. However, mild to moderate inflammation and fibrosis were seen in 9 patients and in 8, respectively. CONCLUSIONS: The papillary architecture is not affected by endoscopic papillary balloon dilation. This may imply that endoscopic papillary balloon dilation preserves papillary function.  相似文献   
999.
Information‐sharing between nurses and nursing assistants is necessary for appropriate inpatient care. Nurses who perceive nursing assistant roles highly may display positive behaviors related to information‐sharing with nursing assistants. This study aims to examine the relationship between nurses' perceptions of nursing assistant roles and the frequency of their sharing information with nursing assistants. Using a self‐administered, cross‐sectional survey questionnaire, data from 2,642 nurses in 182 hospitals were collected. Nurses' perceptions of nursing assistant roles were measured with a scale containing four factors: (i) improving patients' abilities through daily care; (ii) caring for various patients using broad perspectives; (iii) facilitating co‐ordination and co‐operation among team members; and (iv) increasing the amount of information on patients among team members. Information‐sharing behaviors included “expressing,” “asking,” “linguistic response,” and “feedback.” Multiple regression analyses for each nurse's information‐sharing behaviors were conducted. Nurses' perceptions of nursing assistant roles were positively correlated with the frequency of sharing information with nursing assistants. The degree of the correlations differed, depending on the type of information‐sharing behavior. Therefore, improving nurses' understanding of nursing assistant roles might increase their information‐sharing behaviors.  相似文献   
1000.
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