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1.
The loads needed to elicit a positive pivot shift test in a knee with an anterior cruciate ligament (ACL) rupture have not been quantified. The coupled anterior tibial translation (ATT), coupled internal tibial rotation (ITR), and the in situ force in the ACL in response to a valgus torque, an inherent component of the pivot shift test, were measured in 10 human cadaveric knee specimens. Using a robotic/universal force-moment sensor testing system, valgus torques ranging from 0.0 to 10.0 Nm were applied in nine increments on the intact and ACL-deficient knee in flexion ranging from 0 degrees to 90 degrees. At 15 degrees of knee flexion, the coupled ATT and ITR were significantly increased in the ACL-deficient knee when compared to the intact knee. Coupled ATT increased a maximum of 291% (6.7 mm, p<0.05), while coupled ITR increased a maximum of 85% (5.1 degrees, p<0.05). At 30 degrees, the increases in coupled ATT and ITR were significant at valgus loads of 3.3 Nm and greater with a maximum increase in coupled ATT of 137% (6.3 mm, p<0.05) and a maximum increase in coupled ITR of 38% (3.6 degrees, p<0.05). At 45 degrees, coupled ATT increased significantly (maximum of 69%, 4.4 mm, p<0.05), but only at torques > or =6.7 Nm. The in situ force in the ACL was less than 20 N for all flexion angles when a torque between 3.3 and 5.0 Nm was applied. Low valgus torque elicited tibial subluxation in the ACL-deficient knee with low in situ ACL forces, similar to a positive pivot shift test. Thus, application of a valgus torque may be suitable to evaluate ACL-deficient and ACL-reconstructed knees, since subluxation can be achieved with minimal harm to the ACL graft. This work is important in understanding one load component needed for the pivot shift examination; further studies quantifying other load components are essential for better comprehension of the in vivo pivot shift examination.  相似文献   
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Transabdominal resection for esophagocardial cancer and reestablishment of alimentary continuity using bypass methods were performed in 76 patients. Thirteen underwent a bypass with a gastric tube and in 30, a colonic segment was prepared. In the remaining 33, a jejunal segment was used as a bypass organ, with considerable success. The 5 year survival rates were 68.8 per cent in those with stages (I+II), 16.5 per cent in those with stage III, 12.6 per cent in those with stage IV and 22.5 per cent in all cases, indicating similar results compared to those with cancer located in the upper third of the stomach with the limited proximal extension within the esophagocardial junction and operated on during the same period.  相似文献   
4.
Human uterine cervical tissue is composed mainly of fibroblast cells and the extracellular matrix in which collagen types I and III predominate. It is hypothesized that these collagens are degraded by matrix metalloproteinases (MMPs) in the initial step of uterine cervical ripening during parturition. Among the MMPs, MMP-1, -8 and -13 have substrate selectivity for collagen types I and III. In the present study, we examined the regulation of MMP-1 secretion from the human uterine cervix. Immunohistochemistry detected strong staining of MMP-1, but not of MMP-8 or -13, in stromal cells of the pregnant uterine cervix. The MMP-1 expression in the pregnant uterine cervix was further confirmed by Western blot analysis and RT-PCR. To clarify the regulation of MMP-1 production, we subsequently investigated the effects of prostaglandins, inflammatory cytokines and cyclic mechanical stretch on the secretion of MMP-1 from cultured human uterine cervical fibroblast cells. Treatment with prostaglandin (PG)F(2alpha) (10(-7) to 10(-5) mol/l) or interleukin (IL)-1alpha (0.01-1.0 ng/ml) or stimulation with cyclic mechanical stretch increased MMP-1 secretion from cultured human uterine cervical fibroblast cells, with maximal increases of 3.4-, 4.5- and 1.9-fold respectively (24 h of treatment, P < 0.05 for all comparisons). These data suggest that MMP-1 may play a significant role in the degradation of extracellular collagen types I and III in the pregnant uterine cervix during the process of cervical ripening, in response to various stimulations such as PGF(2alpha), IL-1alpha and mechanical stretch.  相似文献   
5.
Medullasin levels in granulocytes of patients with neurological diseases and healthy volunteers were determined by the enzyme immunoassay using mouse monoclonal antibodies against human medullasin and o-phenylenediamine-H2O2 as the detection system of the enzyme activity. One hundred twenty-one out of 159 patients with multiple sclerosis (76.1%) showed positive results (above means of normals + 2SD) in this test, while only 16.9% (24/142) of patients with non-inflammatory neurological diseases had positive results. This enzyme immunoassay method for medullasin is considered to be an useful paraclinical test for the diagnosis of multiple sclerosis.  相似文献   
6.
It is well known that physical exercise can reduce coronary risk factors. But how an aerobic exercise modifies coronary risk factors in relation to severity and physical fitness is still controversial. Fifty-four middle-aged women (mean age, 55 years) completed a 6-month on-site and home-based anaerobic threshold-level exercise program. The changes in coronary risk factor profiles were observed during the pre-intervention and intervention periods. Before the intervention (during control period), most coronary risk factors showed a rather unfavorable trend. After the program, their mean body weight decreased from 56.7 to 55.7 kg (p>0.05) and the proportion of body fat from 30.9 to 27.9% (p>0.05) without any reduction in lean body mass. Systolic blood pressure (SBP) decreased from 129.0 to 125.0 mm Hg (p>0.05) and diastolic blood pressure from 79.5 to 76.6 mm Hg (p>0.05). Fasting plasma glucose (FPG) declined from 109.6 to 103.4 mg/dl (p>0.05). Changes in SBP and FPG were most remarkable in their respective worst tertile. Serum lipids improved only modestly. Maximum oxygen uptake increased from 23.6 to 26.1 ml/kg/min (p>0.01). However, no significant correlations were found between changes in coronary risk factors and those in physical fitness. We conclude that the 6-month aerobic exercise program would modify women’s coronary risk factors depending on their initial values, probably independently of the changes in physical fitness.  相似文献   
7.
PURPOSE: Radiation-induced fibrosis (RIF) is a rare morbid complication of radiotherapy, without an established method of management. RIF treatment with a combination of pentoxifylline (PTX) and alpha-tocopherol (vitamin E; Vit E) was recently prompted by the good results of a clinical trial and an animal study. The present double-blind, placebo-controlled, monocentric study was designed to assess the efficacy of this combination in treating RIF sequelae. PATIENTS AND METHODS: Twenty-four eligible women with 29 RIF areas involving the skin and underlying tissues were enrolled from December 1998 to April 2000. These patients, previously irradiated for breast cancer, were randomly assigned to four balanced treatment groups: (A) 800 mg/d of PTX and 1,000 U/d of Vit E; (B) PTX plus placebo; (C) placebo plus Vit E; and (D) placebo-placebo. The main end point measure was the relative regression of measurable RIF surface after 6 months of treatment. Assessment was completed by depth (with ultrasonography) and associated symptom measures. RESULTS: Twenty-two patients with 27 RIF areas were analyzed at 6 months. Mean RIF surface regression was significant with combined PTX/Vit E versus double placebo (60% +/- 10% v 43% +/- 17%; P =.038). The median slope for the speed of RIF surface area and volume regression was significantly higher for group A than groups B, C, and D. All treatments were well tolerated. CONCLUSION: Six months' treatment of combined PTX/Vit E can significantly reduce superficial RIF. Synergism between PTX and Vit E is likely, as treatment with each drug alone is ineffective, but these results require confirmation in larger series.  相似文献   
8.
Background A role for theTP53 (alias p53) tumor-suppressor gene in chemoresistance has recently been discussed, but little is known about the clinical relevance of theTP53 gene to chemoresistance. To elucidate the relevance ofTP53 status to chemoresistance, we investigated theTP53 gene and TP53 protein expression in tumors from the same patients, before and after chemotherapy. Methods Twenty-one patients with ovarian cancer, who had residual disease after primary surgery, were studied. These patients received chemotherapy consisting of cisplatin, doxorubicin, and cyclophosphamide, and then underwent a second surgery. Polymerase chain reaction-single strand conformation polymorphism analysis and cycle sequencing were performed to determineTP53 mutation. TP53 protein was detected by Western blot analysis. Results Of the 21 patients studied, 9 responded to chemotherapy. Mutation of theTP53 gene was seen in 7 patients (2 responders and 5 nonresponders) before chemotherapy. After chemotherapy, another mutation of the gene was observed in 5 patients, all of whom were nonresponders. TP53 protein was detected in 10 patients (3 responders and 7 nonresponders) before chemotherapy. After chemotherapy, the expression of TP53 protein increased in these 3 nonresponders, and became positive in 2 other nonresponders. Conclusions This study showed for the first time in clinical investigation that alterations toTP53 could develop in association with chemotherapy, and thatTP53 status may relate to the mechanisms of chemoresistance in patients with epithelial ovarian cancer.  相似文献   
9.
Mycotic aneurysms of the subclavian artery are rare. This report describes an experience of 2 rare cases in which transcatheter embolization with metallic coils was performed for the management of these lesions alternative to surgery. Two patients who had been treated with chemotherapy for malignant neoplasms were diagnosed as having mycotic aneurysms of the left subclavian artery. The causes of these lesions were presumed to be the invasion of the arterial wall by the pulmonary abscess in case 1, and wound infection after placement of the reservoir for intraarterial chemotherapy in case 2. In both cases, proximal and distal sites of the aneurysm were embolized with metallic coils. In case 1, the vertebral artery was also embolized with Guglielmi detachable coils to avoid retrograde blood flow. Both aneurysms were completely occluded by a single embolization. In case 1, although weakness and paresthesia of the left hand remained, lethal hemoptysis due to aneurysmal fistulization to the lung parenchyma ceased. In case 2, no neurological deficit except for mild paresthesia in the left thumb had been observed. Both patients died of primary disease 10 and 5 months after the procedure. Transcatheter embolization is technically feasible and effective enough to treat the mycotic aneurysm of the subclavian artery even in the situation in which the surgical option seems to be difficult or risky.  相似文献   
10.
Tumor-associated antigens are promising candidates as target molecules for immunotherapy and a wide variety of tumor-associated antigens have been discovered through the presence of serum antibodies in cancer patients. We previously conducted dendritic cell therapy on 10 malignant melanoma patients and shrinkage or disappearance of metastatic tumors with massive necrosis occurred in two patients. In this study, we found a 29-kDa protein against which antibody was elicited by dendritic cell therapy in one of the two patients. Matrix-assisted laser desorption ionization-time of flight/mass spectrometry analysis of the protein isolated by two-dimensional electrophoresis combined with Western blots revealed that the 29-kDa protein was carbonic anhydrase II (CA-II). Immunohistochemistry of the tumors and normal tissues showed that CA-II was expressed in the tumor vessel but not in normal vessel endothelium. CA-II expression in tumor endothelium was observed as well in other cancers including esophageal, renal, and lung cancers. In an in vitro angiogenesis model, CA-II expression of normal human vein endothelial cells was significantly up-regulated when cells were cultured in the acidic and hypoxic conditions indicative of a tumor environment. These findings suggest that CA-II is a tumor vessel endothelium-associated antigen in melanoma and other cancers, and elicitation of serum anti-CA-II antibody by dendritic cell therapy may be associated with good clinical outcome including tumor reduction.  相似文献   
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