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91.
OBJECTIVES: 1) To determine the factors that predispose towards invasive fungal rhinosinusitis (FS) in immunocompromised children with cancer, and 2) to propose practice guidelines for management of pediatric FS in immunocompromised patients. METHODS: Retrospective chart review of 9 patients who developed invasive FS compared to 8 patients who did not develop invasive FS during the study period. Presenting signs and symptoms, nasal endoscopic findings, radiographs, laboratory studies, histologic and microscopic samples, and outcomes were compared. RESULTS: Seventeen consecutive pediatric immunocompromised patients with hematologic and lymphoid neoplasms underwent nasal endoscopy and biopsy for possible FS. Nine patients were diagnosed with 10 episodes of FS; 1 patient developed FS with different organisms on 2 separate occasions separated by 6 months; 8 patients were not diagnosed with FS. Eight patients had acute myelogenous leukemia (AML); 6 patients had acute lymphoblastic leukemia (ALL); 1 patient had Burkitt's lymphoma, 1 patient had undifferentiated leukemia; and 1 patient had biphenotypic acute leukemia. All patients with FS had an absolute neutrophil count (ANC) 600 or less (range 0-600). All patients with FS had either persistent fevers or sinus symptoms (facial pain, nasal congestion, rhinorrhea). Sinus CT scans were abnormal in all patients with FS and without FS. Two patients with FS had maxillary sinus retention cysts. Operative endoscopic findings were helpful diagnostically when necrosis or ulceration was found. All patients in the non-FS group normalized their ANCs; 2 of the 9 patients in the FS group did not normalize their ANC. These 2 patients died from disseminated FS or from complications due to their immunosuppression. CONCLUSION/SIGNIFICANCE: All patients with FS had either persistent fevers or symptoms localized to the sinuses (facial pain, nasal congestion, or rhinorrhea). Endoscopic examination was helpful when necrosis was detected. We recommend directed biopsies of suspicious lesions, the middle and inferior turbinate, in immunocompromised, neutropenic pediatric patients with cancer who present with either persistent fevers or localizing symptoms to the sinuses. We favor the use of "rush" biopsies over frozen sections because of the better-quality sections and ability to perform appropriate stains.  相似文献   
92.
In breast conservation therapy, the margin status of the specimen predicts local recurrence and determines the need for reexcision. Many surgeons now take, at the time of lumpectomy, multiple separate "cavity margins" (CM) (the entire wall of the residual cavity) as final margins that supersede the oriented lumpectomy margins (LMs). We studied the efficacy of this method in 126 patients (23 with ductal carcinoma in situ [DCIS] only and 103 with invasive carcinoma with or without DCIS) who had an oriented lumpectomy specimen and also had four to six additional CMs. The tumors were evaluated for the following: size, grade, LM status (distance of tumor from margin and, if involved, extent of involvement), vascular invasion, lymph node status, and presence or absence of extensive intraductal component. The additional CM specimens were evaluated for residual carcinoma (if any) and its distance from the inked true margins, and the results were correlated with the corresponding LMs. Only approximately 50% of patients (52 of 103) with histologically positive LMs (defined as carcinoma within 2 mm of the inked surface) had residual carcinoma in their CMs. Additional CM sampling rendered the overall final margin status histologically negative in 61 of 103 (59%) cases with histologically positive LMs, therefore significantly reducing the need for reexcision. Younger patient age, higher number of positive LMs, high tumor grade, and the presence of extensive intraductal component were predictive of residual carcinoma in CM specimens, whereas the distance of carcinoma from the inked surface and the extent of tumor involvement of histologically positive LMs were not. Because CM specimens taken from patients with histologically positive LMs usually lack tumor, we suspect that many positive LMs are likely false positives. Possible factors accounting for false-positive LMs include seepage of ink into crevices of the specimen promoted by excessive inking, tumor friability promoting displacement of tumor into ink, manipulation of specimens for radiographs, and retraction artifact.  相似文献   
93.
Spontaneous dissection of a visceral artery without associated aortic dissection is rare, although more cases have recently been reported because of the advancement of diagnostic techniques. The risk factors, causes, and natural history of spontaneous isolated visceral artery dissection are unclear. Treatment with open surgery, endovascular stenting, or anticoagulation therapy has been proposed; however, there is no consensus on the optimal management. We present three cases of spontaneous and isolated dissection of visceral arteries. Dissection involved the superior mesenteric artery in one and the celiac artery in two. All three patients presented with acute abdominal pain but lacked any peritoneal irritation. The patients were treated nonoperatively with anticoagulants or antiplatelets. No surgical or endovascular intervention was performed. Follow-up imaging studies demonstrated improvement of the dissection in two patients and no change in one patient. All patients were symptom-free over a mean follow-up of 17 months. Nonoperative treatment with close observation is an acceptable strategy in the management of spontaneous isolated dissection of visceral arteries. Emergent intervention is not mandatory in symptomatic patients without evidence of acute bowel ischemia or hemorrhage.  相似文献   
94.

Background

Patients referred to trauma centers often undergo an extensive diagnostic work-up before transfer. The purpose of our study was to quantify and examine the effects of repeat imaging in this population.

Methods

A prospective cohort study of 410 patient transfers was performed. Repeat imaging was conducted at the discretion of the accepting surgeon for multiple reasons. Two groups were compared, those who did and those who did not require repeat imaging.

Results

Overall, 53% of referrals received repeat imaging, at an average cost of $2,985 per patient. This group was older (42 vs 37 y; P < .05), more severely injured (injury severity score, 12 vs 9; P < .05), and experienced longer delays before transfer (244 vs 192 min; P < .05). By using logistic regression analysis, injury severity score was found to be an independent predictor of the need for repeat imaging (P = .003).

Conclusions

Severely injured trauma patients often receive films that ultimately require duplication, resulting in transfer delay, unnecessary morbidity, and increased resource use. Targeted education and development of centralized radiology systems could alleviate some of the burden of unnecessary imaging.  相似文献   
95.
Background Neoadjuvant (preoperative) chemoradiotherapy (CRT) for pancreatic cancer offers theoretical advantages over the standard approach of surgery followed by adjuvant CRT. We hypothesized that histological responses to CRT would be significant prognostic factors in patients undergoing neoadjuvant CRT followed by resection. Methods Since 1994, 193 patients with biopsy-proven pancreatic adenocarcinoma have completed neoadjuvant CRT, and 70 patients have undergone resection. Specimens were retrospectively examined by an individual pathologist for histological responses (tumor necrosis, tumor fibrosis, and residual tumor load) and immunohistochemical staining for p53 and epidermal growth factor receptor. Factors influencing overall survival were analyzed with the Kaplan-Meier (univariate) and Cox proportional hazards (multivariate) methods.Results The estimated overall survival (median±SE) in the entire group of patients undergoing resection was 23±4.2 months, with an estimated 3-year survival of 37%±6.6% and a median follow-up of 28 months. Complete histological responses occurred in 6% of patients. Overexpression of p53 was more common in patients with large residual tumor loads. Tumor necrosis was an independent negative prognostic factor, as were positive lymph nodes, a large residual tumor load, and poor tumor differentiation.Conclusions Histological response to neoadjuvant CRT—as measured by residual tumor load—may be useful as a surrogate marker for treatment efficacy. Characterization of the tumor cells that survive neoadjuvant CRT may help us to identify new or more appropriate targets for systemic therapy.  相似文献   
96.
To assess platelet function profiles in diabetic and nondiabetic patients on aspirin and clopidogrel therapy, two patient populations were included to investigate the 1) acute effects of a 300-mg clopidogrel loading dose (group 1, n = 52) and 2) long-term effects of clopidogrel (group 2, n = 120) on platelet function in diabetic compared with nondiabetic patients already on aspirin treatment. Patients were stratified according to the presence of type 2 diabetes. Platelet aggregation was assessed using light transmittance aggregometry (groups 1 and 2). Platelet activation (P-selectin expression and PAC-1 binding) was determined using whole-blood flow cytometry (group 2). Clopidogrel response was also assessed. In group 1, platelet aggregation was significantly increased in diabetic (n = 16) compared with nondiabetic (n = 36) patients at baseline and up to 24 h following a 300-mg loading dose (P = 0.005). In group 2, platelet aggregation and activation were increased in diabetic (n = 60) compared with nondiabetic (n = 60) subjects (P < 0.05 for all platelet function assays). Diabetic subjects had a higher number of clopidogrel nonresponders (P = 0.04). Diabetic patients have increased platelet reactivity compared with nondiabetic subjects on combined aspirin and clopidogrel treatment. Reduced sensitivity to antiplatelet drugs may contribute to the increased atherothombotic risk in diabetic patients.  相似文献   
97.
BACKGROUND: In the evaluation of the cervical spine (c-spine), helical CT scan has higher sensitivity and specificity than plain radiographs in the moderate- and high-risk trauma population, but is more costly. We hypothesize that institutional costs associated with missed injuries make helical CT scan the least costly approach. STUDY DESIGN: A cost-minimization study was performed using decision analysis examining helical CT scan versus radiographic evaluation of the c-spine. Parameter estimates were obtained from the literature for probability of c-spine injury, probability of paralysis after missed injury, plain film sensitivity and specificity, CT scan sensitivity and specificity, and settlement cost of missed injuries resulting in paralysis. Institutional costs of CT scan and plain radiography were used. Sensitivity analyses tested robustness of strategy preference, accounted for parameter variability, and determined threshold values for individual parameters on strategy preference. RESULTS: C-spine evaluation with helical CT scan has an expected cost of US 554 dollars per patient compared with US 2,142 dollars for plain films. CT scan is the least costly alternative if threshold values exceed US 58,180 dollars for institutional settlement costs, 0.9% for probability of c-spine fracture, and 1.7% for probability of paralysis. Plain films are least costly if CT scan costs surpass US 1,918 dollars or plain film sensitivity exceeds 90%. CONCLUSIONS: Helical CT scan is the preferred initial screening test for detection of cervical spine fractures among moderate- to high-risk patients seen in urban trauma centers, reducing the incidence of paralysis resulting from false-negative imaging studies and institutional costs, when settlement costs are taken into account.  相似文献   
98.
BACKGROUND: Interposition arthroplasty is an option for the treatment of arthritis of the elbow. Conversion to a total elbow arthroplasty can be considered later, when the patient reaches a suitable age. We investigated the results of conversion of an interpositional elbow arthroplasty to a semiconstrained total elbow arthroplasty in a series of patients. METHODS: The results of twelve consecutive linked semiconstrained total elbow arthroplasties in twelve patients who had had a prior interposition arthroplasty for the treatment of degenerative arthritis of the elbow were evaluated at an average of ten years postoperatively. The average age at the time of the total elbow arthroplasty was fifty years, and the average interval from the interposition arthroplasty to the total elbow arthroplasty was 9.9 years. Pain and elbow performance as measured with the Mayo Elbow Performance Score were assessed in a retrospective chart review and an evaluation of questionnaires, and postoperative radiographs were reviewed. RESULTS: At the time of the latest follow-up, postoperative pain was rated as mild or none in ten of the twelve patients, and the result was rated as subjectively satisfactory in ten patients. The average Mayo Elbow Performance Score improved from 32.1 points (range, 10 to 70 points) preoperatively to 80.4 points (range, 40 to 100 points) postoperatively (p < 0.001). According to these objective criteria, there were three excellent, six good, one fair, and two poor results. All of the elbows were stable following the arthroplasty. Radiographs demonstrated a well-fixed prosthesis in all but one patient who had extensive osteolysis at the site of the humeral component. One other patient had radiographic evidence of bushing wear. Both of these patients required revision procedures. CONCLUSIONS: Semiconstrained total elbow arthroplasty can be performed successfully in patients with a prior interposition arthroplasty. Reliable pain relief and a satisfactory result can be achieved in most patients.  相似文献   
99.
BACKGROUND: Parotid area lymph node metastasis from primary scalp and facial cutaneous cancers is a poorly recognized clinical entity partly because of the long time lapse between the index lesion and regional spread. METHODS: A retrospective review of the University of Wisconsin Tumor Registry and Head and Neck Oncology Tumor Board was performed over a 10-year period from 1989 to 1999. One hundred two patients with a malignant parotid mass were identified. Of these, 20 patients were identified with parotid region squamous cell carcinoma and prior index skin cancer of the face or scalp. These patients were analyzed regarding presentation, diagnostic evaluation, interval between index lesion and metastasis, treatment method, and long-term outcome. RESULTS: Approximately 20% of patients (20 of 102) in this series with a malignant parotid mass had presumed metastasis from an identifiable skin primary tumor. The mean time from index lesion to presentation of regional spread was 13.5 months. Seventy percent of the patients (14 of 20) underwent surgery followed by radiation as locoregional therapy, whereas 30% underwent surgery alone. Six (30%) of 20 patients required some degree of facial nerve sacrifice. Three patients (15%) experienced subsequent locoregional failure. Two of six patients from the surgery alone group and one of 14 patients who received surgery plus radiation therapy experienced locoregional relapse. CONCLUSIONS: Parotid area lymph node metastases from scalp and facial cutaneous carcinomas require aggressive therapy to optimize locoregional control. The addition of radiotherapy after parotidectomy is important and should be considered for optimal disease control. Selective neck dissection or radiation may be warranted at the time of parotidectomy. This combined approach is associated with high locoregional control rates and is generally well tolerated.  相似文献   
100.
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