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991.

Background

In the United States, cholesterol stones account for 70% to 95% of adult gallstones and black pigment stones for most of the remainder. Calcium carbonate stones are exceptionally rare. A previous analysis of a small number of pediatric gallstones from the north of England showed a remarkably high prevalence of calcium carbonate stones. The aims of this study were to analyze a much larger series of pediatric gallstones from our region and to compare their chemical composition with a series of adult gallstones from the same geographic area.

Methods

A consecutive series of gallbladder stones from 63 children and 50 adults from the north of England were analyzed in detail using Fourier transform infrared microspectroscopy. Demographic and clinical data were collected on all patients. The relative proportions of each major stone component were assessed: cholesterol, protein and calcium salts of bilirubin, fatty acids, calcium carbonate, and hydroxyapatite.

Results

Thirty-nine (78%) adults had typical cholesterol stones, 7 (14%) had black pigment bilirubinate stones, and only 2 (4%) had calcium carbonate stones. In contrast, 30 (48%) children had black pigment stones, 13 (21%) had cholesterol stones, 15 (24%) had calcium carbonate stones, 3 (5%) had protein dominant stones, and 2 (3%) had brown pigment stones. In children, cholesterol stones were more likely in overweight adolescent girls with a family history of gallstones, whereas black pigment stones were equally common in boys and girls and associated with hemolysis, parenteral nutrition, and neonatal abdominal surgery. Calcium carbonate stones were more common in boys, and almost half had undergone neonatal abdominal surgery and/or required neonatal intensive care.

Conclusion

The composition of pediatric gallstones differs significantly from that found in adults. In particular, one quarter of the children in this series had calcium carbonate stones, previously considered rare. Geographic differences are not the major reason for the high prevalence of calcium carbonate gallstones in children.  相似文献   
992.

Purpose

Continuous monitoring tools can be used to monitor surgical outcomes over time. We illustrate the use of CUmulative SUM (CUSUM) charts in monitoring outcomes of Kasai portoenterostomy for treatment of biliary atresia at a supraregional unit.

Methods

Data on 57 consecutive infants who underwent a Kasai portoenterostomy performed by a single surgeon between June 1994 and June 2006 were collected. A procedure was defined as successful if clearance of jaundice (plasma bilirubin level <20 μmol/l) was achieved within 6 months of surgery. We applied cumulative observed-minus-expected, sequential probability ratio test (SPRT), and zero-resetting SPRT CUSUM charts and compared the results with those of standard aggregate data analyses. An expected failure rate of 43.0%, based on the national average failure rate, was used.

Results

The failure rate observed after 57 operations was 29.8%. The zero-resetting SPRT chart indicated a lower-than-expected failure rate earlier than did the aggregate data analyses and any of the other continuous monitoring techniques.

Conclusions

The CUSUM chart method provides ongoing feedback that can be used for continuous monitoring of the outcome of a procedure to ensure that standards of care are maintained. Its use as a routine monitoring tool in pediatric surgery deserves wider recognition.  相似文献   
993.
Beta-cell apoptosis appears to represent a key event in the pathogenesis of type 1 diabetes. Previous studies have demonstrated that administration of the serine proteinase inhibitor alpha1-antitrypsin (AAT) prevents type 1 diabetes development in NOD mice and prolongs islet allograft survival in rodents; yet the mechanisms underlying this therapeutic benefit remain largely unclear. Herein we describe novel findings indicating that AAT significantly reduces cytokine- and streptozotocin (STZ)-induced beta-cell apoptosis. Specifically, strong antiapoptotic activities for AAT (Prolastin, human) were observed when murine insulinoma cells (MIN6) were exposed to tumor necrosis factor-alpha. In a second model system involving STZ-induced beta-cell apoptosis, treatment of MIN6 cells with AAT similarly induced a significant increase in cellular viability and a reduction in apoptosis. Importantly, in both model systems, treatment with AAT completely abolished induced caspase-3 activity. In terms of its activities in vivo, treatment of C57BL/6 mice with AAT prevented STZ-induced diabetes and, in agreement with the in vitro analyses, supported the concept of a mechanism involving the disruption of beta-cell apoptosis. These results propose a novel biological function for this molecule and suggest it may represent an effective candidate for attempts seeking to prevent or reverse type 1 diabetes.  相似文献   
994.
The combination of improved resection, stabilization, and fusion techniques allows for more aggressive removal of malignant spinal tumors with acceptable mortality and morbidity. Thirty consecutive patients with primary sarcomas of the mobile spine, who were operated on at the authors' institution from January 1970 to December 2000, were included in the current study. Demographic information, tumor location, type of resection, resection margins, local recurrence, and overall survival data were retrieved and analyzed. Treatment consisted of en bloc resection in 12 patients (40%) and piecemeal resections in 18 patients (60%). The resection was classified as wide in seven patients (23.3%), marginal in three patients (10%), and intralesional in 20 patients (66.7%). Pathology reports showed tumor-free resection margins in 12 patients (40%). In the remaining 18 patients (60%), resection margins were positive and resulted in a fivefold increase in the risk of a local recurrence. Ninety-two percent of the patients with local recurrence died of sequelae associated with the local recurrence. Primary sarcomas of the mobile spine in certain cases, can be removed completely with tumor-free resection margins. En bloc resection with tumor-free margins provides substantial improvement in overall survival.  相似文献   
995.
PURPOSE: The endovascular approach to external iliac artery (EIA) disease extending into the common femoral artery (CFA) has been avoided because of problems with stent placement across the inguinal ligament. Surgical treatment for this disease distribution includes extensive endarterectomy or bypass procedures or both. We report our initial experience with a combined open and endovascular approach to these patients. METHODS: We performed a retrospective analysis of all patients who underwent intraoperative EIA stenting after CFA endarterectomy/patch angioplasty between 1997 and 2000. Stents were positioned to end at the proximal endarterectomy endpoint, without crossing the inguinal ligament. Technical success, hemodynamic success, and clinical success were determined according to Society of Vascular Surgery/International Society of Cardiovascular Surgery criteria. Life-table analysis was performed for patency. RESULTS: Thirty-four patients (mean age, 68 years; 23 male, 11 female) had combined endovascular and open treatment of iliofemoral occlusive disease. Indications were claudication in 41% and critical limb ischemia in 59%. Femoral reconstruction included endarterectomy with patch angioplasty in all patients. EIA stent deployment incorporated the stenotic iliac segment and the proximal endpoint of the endarterectomy in all patients. Four patients (12%) also needed common iliac angioplasty at the same time for proximal iliac disease, and 14 patients (41%) also needed distal revascularization for associated femoropopliteal or tibial disease. Technical success and hemodynamic success were achieved in 100% of patients. Clinical success was achieved in 97% of patients. The mean postoperative increase in ankle-brachial index in patients with inflow procedures only was 0.36 (range, 0.1 to 0.85). The overall complication rate was 15%. With a mean follow-up period of 13 months (range, 0.5 to 28 months), 1-year primary patency and primary-assisted patency rates were 84% and 97%, respectively. No perioperative mortality was seen. CONCLUSION: EIA stenting as an adjunct to CFA endarterectomy/patch angioplasty allows for more localized surgery than conventional bypass. This approach also allows a better interface between the stent and endarterectomy than staged preoperative stenting. Technical success and early patency rates are excellent.  相似文献   
996.
BACKGROUND: The purpose of this retrospective study was to report the results, after a minimum of 18.5 years of follow-up, in a consecutive series of total hip arthroplasties performed with an alumina-on-alumina combination. METHODS: One hundred and eighteen consecutive total hip arthroplasties were performed in 106 patients between 1979 and 1980. The prostheses combined a 32-mm alumina head and an all-alumina socket. Both components were cemented in eighty-five hips, both components were implanted without cement in twenty-nine, and only the stem was cemented in four. The mean age of the patients at the time of the index arthroplasty was 62.2 years (range, thirty-two to eighty-nine years). RESULTS: At the 18.5 to 20.5-year follow-up evaluation, forty-five patients (fifty-one hips) were alive and had not had a revision, twenty-five patients (twenty-five hips) had undergone revision of one or both components, twenty-seven patients (thirty hips) had died, and nine patients (twelve hips) had been lost to follow-up. The mean Merle d'Aubigné hip score (and standard deviation) was 16.2 +/- 1.8 points at the latest follow-up evaluation. The rate of survival at twenty years, with revision for any reason as the end-point, was 85.6% for the cementless cups compared with 61.2% for the cemented cups and 84.9% for the cementless stems compared with 87.3% for the cemented stems. Wear of the prosthetic components was undetectable on plain radiographs. Periprosthetic cystic or scalloped lesions requiring the use of allograft bone during revision were present in three of the twenty-five revised hips. In addition, seven hips had moderate acetabular osteolysis treated with a 4-mm-larger cup. No fracture of the alumina socket or head was recorded. The mean acetabular wear rate in this series was <0.025 mm/yr. CONCLUSION: With the alumina-on-alumina total hip arthroplasty, minimal wear rates and limited osteolysis can be expected up to twenty years after the operation, provided that sound acetabular component fixation is obtained.  相似文献   
997.
Our objective was to examine patterns of withholding/withdrawal (WH/WD) of life support in trauma patients and to determine whether WD/WH of life support is used more frequently in elderly patients. This is a retrospective cohort study of injured elderly (> or = 65 years) and young patients (< 65 years) from 1994 through 1998 treated at a surgical intensive care unit in a community tertiary-care hospital. We studied the cases of 82 patients (30 elderly and 52 young patients) with WH/WD of life support after injury. Our main outcome measures were demographic and clinical characteristics of elderly and young patients undergoing WH/WD of life support after injury with an association between age and WH/WD of life support. Of 102 total trauma patient deaths 82 had WH/WD of life support. This mode was chosen in 52 (80%) patients under the age of 65 and in 30 (81%) patients age 65 or greater. Patients in the younger cohort had a higher mean Injury Severity Score and Abbreviated Injury Score of 5 (P < 0.05). The elderly cohort had a higher incidence of pre-existing disease (< 0.001). Length of stay was similar between the populations. We conclude that the elderly were no more likely to have WH/WD of life support than were younger patients. However, the older patients were less severely injured as measured by Injury Severity Score and percentage with Abbreviated Injury Score head of 5. Other factors such as the presence of pre-existing disease may influence the decision to withhold or withdraw life support to a greater degree than the actual severity of injuries.  相似文献   
998.
OBJECTIVE: To evaluate whether gastrin-releasing peptide (GRP) and GRP receptor (GRP-R) expression correlate with tumor behavior and to examine the mitogenic actions of GRP on neuroblastomas. SUMMARY BACKGROUND DATA: Neuroblastoma is the most common solid tumor of infants and children. Despite recent advances in multimodality treatment regimens, the survival for advanced-stage tumors remains dismal. Neuroblastomas are known to produce GRP; however, the proliferative effects of GRP on neuroblastomas have not been elucidated. METHODS: Sections of paraffin-embedded neuroblastomas from 33 patients were analyzed for GRP and GRP-R protein expression by immunohistochemistry. Functional binding of GRP-R to the Ca2+ signaling pathway was examined. In addition, the proliferative effect of GRP on neuroblastoma cells (SK-N-SH, IMR-32, SH-SY5Y, LAN-1) was determined. RESULTS: Immunohistochemical analysis showed GRP and GRP-R protein expression in neuroblastomas; an increased expression of GRP-R was noted in a higher percentage of undifferentiated tumors compared with tumors that were benign. GRP-R mRNA was confirmed in neuroblastoma cell lines. GRP treatment resulted in intracellular calcium [Ca2+]i mobilization in two cell lines (SK-N-SH, LAN-1). GRP treatment stimulated growth of all four neuroblastoma cell lines; this effect was inhibited in SK-N-SH cells by pretreatment with GRP antibody. CONCLUSIONS: These findings show increased GRP-R expression in the more aggressive and undifferentiated neuroblastomas. The synchronous expression of GRP and its receptor, GRP-R, suggests a role for these proteins in tumor growth. Moreover, these findings show enhanced proliferation of neuroblastoma cells in vitro after GRP treatment, suggesting that GRP may act as an autocrine and/or paracrine growth factor for neuroblastomas. Treatment with specific GRP-R antagonists may provide novel adjuvant therapy for neuroblastomas in children.  相似文献   
999.
OBJECTIVE: To determine the clinical features, natural history, and role of surgery for gastrointestinal manifestations of the multiple endocrine neoplasia type 2 (MEN 2) syndromes. SUMMARY BACKGROUND DATA: The MEN 2 syndromes are characterized by medullary thyroid carcinoma and other endocrinopathies. In addition, some patients with MEN 2A develop Hirschsprung's disease (HD), and all patients with MEN 2B have intestinal neuromas and megacolon that can cause significant gastrointestinal problems. METHODS: From 83 families with MEN 2A, eight patients with HD were identified (MEN 2A-HD). These and all patients with MEN 2B followed at the authors' institution (n = 53) were sent questionnaires to describe the onset and type of gastrointestinal symptoms and treatment they had before the diagnosis of MEN 2. Records of all patients responding were reviewed, including radiographic imaging, histology, surgical records, and genetic testing. RESULTS: Thirty-six of the 61 patients (59%) responded (MEN 2A = 8, MEN 2B = 28) to the questionnaires. All patients with MEN 2A-HD were operated on for HD 2 to 63 years before being diagnosed with MEN 2. All patients responding were underweight as infants and had symptoms of abdominal pain, distention, and constipation. Eighty-eight percent had hematochezia, 63% had emesis, and 33% had intermittent diarrhea before surgery. All patients with MEN 2A-HD had rectal biopsies with a diverting colostomy as the initial surgical procedure. This was followed by a colostomy takedown and pull-through procedure at a later interval. Ninety-three percent of patients with MEN 2B had gastrointestinal symptoms 1 to 24 years before the diagnosis of MEN 2. Symptoms included flatulence (86%), abdominal distention or being underweight as a child (64%), abdominal pain (54%), constipation or diarrhea (43%), difficulty swallowing (39%), and vomiting (14%). Seventy-one percent of patients with MEN-2B with gastrointestinal symptoms had radiographic imaging, 32% were admitted to the hospital, and 29% underwent surgery. CONCLUSIONS: Patients with MEN 2A-HD had a typical HD presentation and always required surgery. Patients with MEN 2B have significant gastrointestinal symptoms, but less than a third had surgical intervention. Understanding the clinical course and differences in these patients will improve clinical management.  相似文献   
1000.
OBJECTIVES: Pulmonary complication is a frequent morbid event after esophagectomy for cancer. Its prediction may help select patients for preoperative rehabilitation. METHODS: We performed a retrospective review of 292 patients (231 men and 61 women; mean age, 60.1 years) who underwent esophagectomy for cancer between 1980 and 2000. Data were analyzed to identify factors associated with the development of pulmonary complications (reintubation for isolated respiratory failure and pneumonia). A scoring system was developed, and its ability to predict complications was assessed. RESULTS: Resection was performed for squamous cancer (n = 100), adenocarcinoma (n = 186), and other histologic types (n = 6) in patients with stages 0 or I (n = 53), II (n = 94), III (n = 114), and IV (n = 23) disease. Pulmonary complications, which developed in 78 (27%) patients, were associated with a 4.5-fold increase in operative mortality (7%-32%). Multivariable analysis identified independent predictors of pulmonary complications to be patient age (odds ratio [OR], 1.31; 95% confidence interval [CI], 0.99-1.74; P =.059), percentage forced expiratory volume in 1 second (OR, 1.21; 95% CI, 1.07-1.38; P =.003), and possibly performance status (OR, 1.48; 95% CI, 0.88-2.50; P =.14). A scoring system using these 3 covariates was developed, which predicted incremental risk of pulmonary complications (P =.013). The incremental risks of cardiovascular and overall cardiopulmonary complications were also predicted with this scoring system (P <.01 for each). CONCLUSIONS: A scoring system using patient age, spirometry, and performance status helps predict the likelihood of pulmonary and cardiovascular complications after esophagectomy and can help select patients who may benefit from preoperative cardiopulmonary rehabilitation.  相似文献   
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