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71.
BACKGROUND: Recently, we have described a drug (cyclophosphamide [CP] plus busulfan [BU])-induced skin allograft tolerance in mice that can regularly overcome fully H-2-mismatched barriers. Using this method, we have investigated whether or not this regimen can prolong the survival of heart allografts and inhibit the development of posttransplant cardiac allograft vasculopathy (CAV). METHODS: The components of the method are intravenous administration of 1 x 108 allogeneic spleen cells on day 0, intraperitoneal injection of 200 mg/kg of CP and 30 mg/kg of BU on day 2, and intravenous injection of T cell-depleted 1 x 107 allogeneic bone marrow cells from the same strain of mice on day 3. Heart grafting was performed on day 28. Chimerism in peripheral blood was followed by flow cytometric analysis, and histological analysis was performed at various times after grafting. RESULTS: In a fully major histocompatability complex (MHC)-mismatched combination of B10.D2 (H-2d, IE+)-->B10 (H-2b, IE-), stable, multilineage-mixed chimerism was observed permanently. B10.D2 heart grafts were accepted permanently in a donor-specific manner, and posttransplant CAV did not develop. CONCLUSIONS: These results demonstrated that the drug-induced tolerance recently established by us can regularly induce a long-lasting heart allograft tolerance without development of CAV.  相似文献   
72.
The management of clival chordoma remains problematic. We present the case of a 48-year-old woman with clival chordoma who underwent multiple surgeries and radiation therapy, including gamma knife stereotactic radiosurgery (GK-SRS), during a 10-year clinical course. The tumor was initially removed by gross total resection via the trans-sphenoidal approach, followed by external linac radiation therapy. The tumor recurred at the clivus 5 years after the initial operation. After repeated trans-sphenoidal removal of recurrent tumors, she twice underwent GK-SRS for a tumor remnant adjacent to the brainstem. Although this part of the tumor was controlled by GK-SRS, there was further tumor extension toward the sphenoid and maxillary sinuses. Ultimately, lower cranial nerve dysfunction developed due to tumor extension into the lower part of the clivus and the patient died of respiratory failure. Autopsy revealed the tumor to extend from the lower clivus to the bilateral middle fossae. The lower part of the tumor extended to the nasal cavity and to the posterior wall of the pharynx, resulting in compression of the upper pharyngeal region. The tumor around the jugular foramen compressed the lower cranial nerves bilaterally. Tumor cells did not, however, invade the intradural space microscopically. Although chordoma is not biologically malignant, this tumor can show massive extension with destruction of bony structures and extracranial invasion of connective tissues. Therefore, the optimal treatment strategy is to remove the tumor mass as extensively as possible, including normal bony structures and connective tissues surrounding the tumor, using skull base surgical techniques.  相似文献   
73.
BACKGROUND: Allogeneic chimerism has been established in graft-accepting recipients and the donor cells in the host may act in a major way to facilitate the induction of tolerance. In this study, we examined the effects of allogeneic chimerism after injecting donor bone marrow cells (BMCs) mixed with splenocytes (SPLCs) to the sublethally conditioned recipients. METHODS: In BALB/c(H-2(d)) to B6(H-2(b)) combination, B6 recipients were irradiated at 7.5 Gy and were injected a mixture of donor BMCs and SPLCs intravenously. On day 90 after injection, the degree of chimerism in peripheral blood lymphocytes (PBL) and in the splenocytes was checked by flow cytometry. RESULTS: In groups which were injected varying BMCs, when > 45 x 10(6) BMCs were injected into B6, a large percentage of donor cells were detected in PBL and in the spleen. In contrast, when < 30 x 10(6) BMCs were injected into B6, only a small percentage of donor cells were detected. In the groups which were injected 3 x 10(6) BMCs with varying SPLCs, when > 10 x 10(6) SPLCs were added, a large percentage of donor cells were detected in PBL and SPLCs, but a small percentage of donor cells were detected with the addition of < 3 x 10(6) SPLCs. A high percentage of chimeric mice showed donor specific tolerance in vitro, mixed lymphocyte responses, and in vivo, skin grafting. In contrast, only a small percentage of chimeric mice showed no donor specific tolerance by skin grafting. CONCLUSION: These findings suggested that even a low dose of BMCs can establish a state of allogeneic chimerism and donor specific tolerance if combined with SPLCs.  相似文献   
74.
OBJECTIVE: To determine the precise in vivo interaction between T-cell costimulatory blockade and conventional immunosuppression in transplantation. SUMMARY BACKGROUND DATA: Blocking B7 or CD154 T-cell costimulatory activation pathways prevents allograft rejection in small and large animal transplant models and is considered a promising strategy for clinical organ transplantation. METHODS: A fully MHC-mismatched vascularized mouse cardiac allograft model was used to test the interactions between anti-CD154 or CTLA4Ig monotherapy and conventional immunosuppressive drugs in promoting long-term graft acceptance. The frequency of alloreactive T cell was measured by ELISPOT. Chronic rejection was examined by histology. RESULTS: Cyclosporine, tacrolimus, and anti-IL-2R monoclonal antibody therapy abrogated the effect of a single-dose protocol of anti-CD154 therapy. In contrast, rapamycin acted synergistically with anti-CD154 therapy in promoting long-term allograft survival. The addition of calcineurin inhibitors did not abolish this synergistic effect. Intense CD154-CD40 blockade by a multiple-dose schedule of anti-CD154 resulted in long-term graft survival and profound alloreactive T-cell unresponsiveness and overcame the opposite effects of calcineurin inhibitors. CTLA4Ig induced long-term graft survival, and the effect was not affected by the concomitant use of any immunosuppressive drugs. CONCLUSIONS: The widespread view that calcineurin inhibitors abrogate the effects of T-cell costimulatory blockade should be revisited. Sufficient costimulatory blockade and synergy induced by CD154 blockade and rapamycin promote allograft tolerance and prevent chronic rejection.  相似文献   
75.
BackgroundSagittal spino-pelvic malalignment in patients with chronic low back pain (CLBP) have been reported in the past, which may also affect cervical spine lesions. The purpose of this study is to investigate the cervical alignment in patients with CLBP.MethodOf the patients who visited an orthopedic specialist due to low back pain lasting more than three months, 121 cases (average 71.5-years-old, 46 male and 75 female) with whole standing spinal screening radiographs were reviewed (CLBP group). Cervical parameters included cervical lordosis (CL), C2–C7 sagittal vertical axis (C2-7 SVA), and the T1 slope minus CL (T1S-CL). Cervical spine deformity was defined as C2-7 SVA >4 cm, CL <0°, or T1S-CL ≧20°. We compared the cervical alignment of these patients with 121 age and gender matched volunteers (control group).ResultsThe prevalence of cervical spine deformity was significantly higher in the CLBP group than in the control group (20.7% vs. 10.7%, P = 0.034). The mean CL was smaller in the CLBP group than in the control group (16.1° vs. 21.4°, P = 0.002). The mean C2-7 SVA was 17.6 mm vs. 18.7 mm in the CLBP group and in the control group, respectively (P = 0.817). The mean T1S-CL was larger in the CLBP group than in the control group (9.1° vs. 3.5°, P < 0.001). Multivariate analysis showed that people with CLBP were more likely to have cervical deformities than people without CLBP (odds ratio 2.16, 95% confidence interval 1.006 to 4.637).ConclusionsThis study results suggest that people with CLBP present with worse cervical sagittal alignment and higher prevalence of cervical spine deformities than age and gender matched volunteers with no CLBP. This means CLBP impacts cervical spine lesions negatively.Level of evidenceⅣ  相似文献   
76.
Shirouzu Y, Ohya Y, Suda H, Asonuma K, Inomata Y. Massive ascites after living donor liver transplantation with a right lobe graft larger than 0.8% of the recipient’s body weight.
Clin Transplant 2010: 24: 520–527.
© 2009 John Wiley & Sons A/S. Abstract: Background: There are only limited data on post‐transplant ascites unrelated to small‐sized grafts in living donor liver transplantation (LDLT). Methods: The subjects were 59 adult patients who had received right lobe LDLT with a graft weight‐to‐recipient weight ratio (GRWR) > 0.8%. Patients were divided into either Group 1 (n = 14, massive ascites, defined as the production of ascitic fluid > 1000 mL/d that lasted longer than 14 d after LDLT) or Group 2 (n = 45, no development of massive ascites). Patients were followed for a median period of 3.0 yr (range, 0.5–7.5 yr). Results: Group 1 had both higher Model for End‐Stage Liver Disease score and Child‐Pugh score than Group 2. Portal venous flow volume just after reperfusion was significantly greater in Group 1 than Group 2 (307.8 ± 268.8 vs. 176.2 ± 75.0 mL/min/100 g graft weight, respectively; p < 0.05). Post‐transplant infectious complications including ascites infection developed more frequently within the first post‐transplant month in Group 1. Massive ascites was significantly associated with early graft loss (p < 0.05). Conclusion: Post‐transplant massive ascites associated with portal over‐perfusion into the graft liver can develop in patients with a GRWR over 0.8%. Recipients with post‐transplant massive ascites require careful management to prevent infection.  相似文献   
77.
BACKGROUND: Although knowledge of cancer invasion of the portal bifurcation is vitally important in planning an operation for perihilar cholangiocarcinoma, the diagnostic capability of multidetector-row computed tomography (MDCT) for this purpose has not been assessed. We evaluated how well MDCT could identify cancer invasion of the portal bifurcation by perihilar cholangiocarcinoma. METHODS: Between April 2003 and June 2005, perihilar cholangiocarcinoma was resected in 87 patients, 83 of whom underwent MDCT within 1 month before the surgery. Three-dimensional volume-rendered (3DVR) and multiplanar reformation (MPR) images were examined for evidence of portal vein invasion. Agreement with intraoperative and pathologic findings was assessed. Portal bifurcation findings by 3DVR and MPR were classified into no portal vein stenosis, unilateral stenosis, or more extensive stenosis, and also into tumor contact with the bifurcation in no, one of two, or two projections. RESULTS: For macroscopic portal vein invasion, sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were 81.5, 91.1, 81.5, 91.1, and 88.0% in 3D portography and 96.3, 92.6, 86.7, 98.1, and 94.0% in MPR, respectively. Findings by both 3DVR and MPR were significantly correlated with depth of cancer invasion (p < 0.001). CONCLUSION: MDCT is useful in assessing cancer invasion of the portal vein bifurcation by perihilar cholangiocarcinoma.  相似文献   
78.
Objective: The efficacy of esophagectomy with three-field lymph node dissection in surgical treatment for patients with squamous cell carcinomas of the lower thoracic esophagus remains controversial. This report documents the outcomes of this surgical procedure for a large series. Methods: From February 1986 to November 1998, 437 patients with squamous cell carcinomas of the thoracic esophagus underwent transthoracic esophagectomy with three-field lymph node dissection. One hundred and sixteen of these had cancer of the lower thoracic esophagus. To avoid the influence of adjuvant therapy on survival, 20 who also received radiation and/or chemotherapy were excluded, leaving 96 patients who were retrospectively analyzed. Results: The operative morbidity, and 30-day and in-hospital mortality rates were 62, 0, and 3%, respectively. The overall 1-, 3-, and 5-year survival rates were 89, 65, and 59%, with a median survival of 76 months. In those with lymph node metastases (66% of cases), the values were 87, 56, and 48%, as compared with 94, 84, and 79%, respectively (P=0.005) for patients without lymph node metastasis. Factors significantly influencing the overall survival rates were patient age (≥65 vs. <65), clinical N status (cN1 vs. cN0), clinical M status (cM1 vs. cM0), longitudinal tumor length of resected specimen (≥5 vs. <5 cm), pathologic T status (pT3 vs. pT1, 2), pathologic N status (pN1 vs. pN0), lymphatic invasion (positive vs. negative), vascular invasion (positive vs. negative) and intramural metastasis (present vs. absent). Independent prognostic factors for survival determined by multivariate analysis were pathologic T status (P=0.02), pathologic N status (P=0.03), and presence of intramural metastasis (P=0.04). Additional pathologic M1 status, cervical or celiac lymph node metastasis, was without significant influence. Conclusions: Patients with pathologic T3 tumors with both pathologic N1 status and the presence of intramural metastasis in the lower thoracic esophagus had a poor prognosis. Cervical or celiac lymph node metastasis in patients with carcinomas of the lower thoracic esophagus should be distinguished from pathologic M1 status in the UICC-TNM staging system.  相似文献   
79.
Cardiovascular mortality is elevated in patients with end-stage renal disease (ESRD), especially in those with diabetes mellitus. Although the higher cardiovascular death rate in diabetic ESRD patients may be the result of more advanced atherosclerotic changes of the arterial wall, this has not been documented previously. Aortic stiffness was compared between ESRD patients with and without diabetes, and the impact of aortic stiffness on cardiovascular mortality was examined in a prospective, observational cohort study. The cohort consisted of 265 ESRD patients on hemodialysis, including 50 diabetic patients studied between June 1992 and December 1998. At baseline, the diabetic ESRD patients had significantly higher aortic pulse wave velocity (PWV), a noninvasive measure of aortic stiffness, than the nondiabetic patients. During a mean follow-up period of 63 mo, 81 deaths, including 36 cardiovascular deaths, were recorded. Kaplan-Meier analysis revealed higher all-cause or cardiovascular mortality rates in the diabetic as compared with the nondiabetic patients and also in those with higher aortic PWV than those with lower aortic PWV. The effect of diabetes on cardiovascular death was significant in the Cox model, including age, years on hemodialysis, gender, smoking, C-reactive protein, hematocrit, and body mass index as covariates. However, when aortic PWV was included as a covariate, the impact of diabetes was no longer significant, whereas aortic PWV was a significant predictor. In a model including 13 covariates, aortic PWV remained a significant predictor for cardiovascular and overall mortality but not for non-cardiovascular death. These results demonstrate that the increased aortic stiffness of the ESRD patients with diabetes mellitus contributed to the higher all-cause and cardiovascular mortality rates.  相似文献   
80.
A 70-year-old male with right renal mass incidentally found by annual check-up using ultrasound, was referred to Department of Urology, Jikei University Affiliated Kashiwa Hospital. He was diagnosed as having right renal cell carcinoma with vena caval tumor thrombus extending above the diaphragm (T3c) preoperatively. The day before the scheduled day of operation, right pulmonary infarction caused by spontaneous migration of vena caval tumor thrombus of right renal cell carcinoma developed. Although arterial blood gas findings were poor, he only had low grade chest pain without shock. Therefore, we successfully performed right radical nephrectomy and thrombectomy of right pulmonary artery the next day. He was discharged 42 days postoperatively, but, he died from acute heart failure 9 months after the operation.  相似文献   
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