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31.
There are various changes in the thyroid gland and its function in chronic renal failure (CRF). These changes include lower levels of circulating thyroid hormone, altered peripheral hormone metabolism, decreased binding to carrier proteins, possible reduction in tissue hormone content, and increased iodine storage in the thyroid gland. The decrease of excretion of urinary iodine in CRF increases serum inorganic iodine level and iodine content of the thyroid, which consequently enlarges the gland. This study is designed to investigate the prevalence of goiter and thyroid dysfunction in patients with end-stage renal disease (ESRD) on hemodialysis (HD) in an iodine-deficient community. Eighty-seven (40 females and 47 males) HD patients and 169 (79 females and 90 males) healthy individuals as controls are included. Sex ratios for the patient and control groups are 0.85 and 0.88, respectively. Mean ages for the patient and control groups are 42.94 +/- 11.88 and 40.20 +/- 10.72 years, respectively. Examination of the thyroid gland using ultrasonography along with simultaneous measurement of blood levels of free-T4 (FT4), free-T3 (FT3), and thyrotropin (TSH) are made for every individual. The presence of goiter demonstrable by ultrasonography is found in 32.2% of the uremic patients and in 23.5% of the controls and its prevalence increases with age (P = 0.01). In 32 (36.8%) of the patients and 29 (17.1%) of the controls at least one thyroid nodule is found in ultrasonography. Between patients with or without a nodular goiter the authors could not observe any difference for duration of dialysis and serum levels of TSH, FT4, FT3, calcium, and albumin. In ESRD patients the prevalence of nodular goiter is higher for females (47.5% vs. 27.7%, P = 0.045) and increases with age (P = 0.04). Though incidence of hyperthyroidism is found to be similar for the two groups (1.14% in ESRD patients vs. 1.10% in controls), hypothyroidism is observed in 3.4% of ESRD patients but only 0.6% of controls. This high incidence of hypothyroidism and nodular goiter in ESRD patients shows that screening for thyroid dysfunction and goiter, using appropriate laboratory tests and ultrasonography, should be considered in evaluation of every ESRD patient.  相似文献   
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33.
AIM: To evaluate the effects of chronic smoking on color vision in young subjects. METHODS: This study included 91 smokers and 88 non-smokers (a total of 179 volunteers) without any ophthalmologic and systemical disorders. The subjects were between 18-40 years of age with a best corrected visual acuity (BCVA) of 20/20, normal anterior and posterior segment examinations and normal intraocular pressure. The color vision of the subjects were evaluated with Farnsworth-Munsell 100 Hue test (FMHT). The total error scores and axis calculation were performed for each subject and the results correlated. RESULTS: Mean age and the standard deviation was 28±5y in the smokers group, and 26.7±5.5y in the control group (P=0.101). Sex distribution was similar in the two groups (P=0.365). There was no significant correlation between age and FMHT total error scores (P=0.069). Median of FMHT total error scores of smokers and non-smokers were 65 and 50.50, respectively. FMHT total error scores was found significantly higher in smokers than non-smokers (P=0.004). There was no statisticaly significant difference between smoker and non-smoker groups with respect to axis ratio calculation (P=0.611). There was no significant correlation with FMHT total error scores with neither smoking duration nor number of cigarettes smoked per day (P=0.405, P=0.454, respectively). CONCLUSION: This study suggested that chronic smoking affects the color vision of young smokers but this may not be sector selective.  相似文献   
34.
The severity of pulmonary emphysema can be affected by exposure to cigarette smoke in several ways. Inactivation of alpha-1-antitrypsin and recruitment of leukocytes to lung airways shifts the protease-antiprotease balance towards increased elastolytic activity. The present study demonstrates an additional effect of cigarette smoke inhalation and retardation of the repair process and of the neosynthesis of cross-linked elastin. Hamsters with elastase-induced emphysema, exposed to cigarette smoke for 1 wk immediately after elastase administration, showed a 40% reduction of 14C-lysine incorporation into the elastin-specific cross-links, desmosine, and isodesmosine. Concomitantly, there was a decrease in the level of lung lysyl oxidase to that observed in uninjured control animals, in sharp contrast to the sevenfold increase in lysyl oxidase activity in hamsters with elastase-induced emphysema recovering under atmospheric conditions. These findings suggest that impairment of the production of lysyl oxidase and the resynthesis of cross-linked elastin by smoke inhalation exacerbates alveolar destruction.  相似文献   
35.
OBJECTIVE: To investigate the computed tomography (CT) features of malignant pleural mesothelioma (MPM) cases, comparing them to those in other malignant and benign pleural diseases. MATERIALS AND METHODS: We reviewed the CT findings of 215 patients; 99 with MPM, 39 with metastatic pleural disease (MPD), and 77 with benign pleural disease. The findings were evaluated in univariate and multivariate analysis for differentiation of pleural diseases. RESULTS: In patients with MPM, the most common CT features were circumferential lung encasement by multiple nodules (28%); pleural thickening with irregular pleuropulmonary margins (26%); and pleural thickening with superimposed nodules (20%). In the majority (70%) of cases, there was rind-like extension of tumor on the pleural surfaces. In multivariate analysis, the CT findings of "rind-like pleural involvement", "mediastinal pleural involvement", and "pleural thickness more than 1 cm" were independent findings in differentiating MPM from MPD with the sensitivity/specificity values of 70/85, 85/67, and 59/82, respectively. "Rind-like pleural involvement", "mediastinal pleural involvement", "pleural nodularity" and "pleural thickness more than 1 cm" were independent findings for differentiation of malignant pleural diseases (MPM+MPD) from benign pleural disease with the sensitivity/specificity values of 54/95, 70/83, 38/96, and 47/64, respectively. Invasion of thoracic structures such as pericardium, chest wall, diaphragm, mediastinum, with pleural disease and nodular involvement of fissures, was detected infrequently; however, since these invasions were not seen in benign pleural diseases, it was concluded these invasions, if detected on a CT scan, directly suggested malignancy. CONCLUSION: A patient has extremely high probability of malignant pleural disease if one or more of these CT findings are found and the possibility of MPM is high. These findings may be important for patients in bad state or patients who do not want any invasive biopsy procedures. It is also possible to identify cases with a low probability of malignant disease.  相似文献   
36.
Metastatic prostate cancer may respond initially to hormone suppression, with involution of tumor sites, but ultimate tumor progression is inevitable. Our aim was to detect the proportion of bone and soft-tissue lesions that represent metabolically active tumor sites in patients with progressive metastatic prostate cancer. METHODS: In a prospective study, we compared 18F-FDG and L-methyl-11C-methionine (11C-methionine) PET with conventional imaging modalities (CIM), which included the combination of 99mTc-methylene diphosphonate scintigraphy, CT, or MRI. Twelve patients with prostate cancer, increasing levels of prostate-specific antigen (PSA), and at least 1 site (index lesion) with new or increasing disease on CIM were studied. The total numbers of soft-tissue and bone-tissue lesions, in a site-by-site comparison, were calculated for all imaging modalities. RESULTS: The sensitivities of 18F-FDG PET and 11C-methionine PET were 48% (167/348 lesions) and 72.1% (251/348 lesions), respectively, with CIM being used as the 100% reference (348/348). 11C-Methionine PET identified significantly more lesions than 18F-FDG PET (P < 0.01). All 12 patients with progressive metastatic prostate cancer had at least 1 lesion site of active metabolism for 18F-FDG or 11C-methionine, which could be used as an index lesion to monitor the metabolic response to therapy. A significant proportion of lesions (26%) had no detectable metabolism of 18F-FDG or 11C-methionine. Although technical factors cannot be totally excluded, we believe that metabolically inactive sites may be necrotic or dormant. More than 95% (251/258) of metabolically active sites (72% of the total number of lesions detected by CIM) metabolize 11C-methionine. 18F-FDG uptake is more variable, with 65% of metabolically active sites (48% of the total number of lesions detected by CIM). CONCLUSION: These findings reflect the different biologic characteristics of the lesions in a heterogeneous tumor such as prostate cancer and suggest that a time-dependent metabolic cascade may occur in advanced prostate cancer, with initial uptake of 11C-methionine in dormant sites followed by increased uptake of 18F-FDG during progression of disease.  相似文献   
37.
STUDY DESIGN: The 5 year review of patients referred to one center. OBJECTIVE: To report spinal cord infarction secondary to vascular occlusion from disease in a lower thoracic intervertebral foramen. METHOD: The clinical and imaging findings of two cases with acute spinal cord dysfunction are presented. SETTING: Midlands Centre for Spinal Injuries, England. RESULTS: The CT and MR imaging features revealed lower thoracic unilateral foraminal occlusion due to acute facet joint septic arthritis in a diabetic patient, and secondary to chronic hypertrophic osteophytes in a second hypertensive individual. The presumed mechanism of infarction was occlusion of the artery of Adamkiewicz. CONCLUSION: Foraminal disease in the lower thoracic levels needs to be entertained in cases of unexplained nontraumatic acute spinal cord dysfunction.  相似文献   
38.
PURPOSE: In this prospective study we aimed to describe our new technique; dehydrated human dura mater as an interposition graft in patients undergoing benign vesicovaginal fistula repair (VVF). PATIENTS AND METHODS: Eleven patients with benign VVFs aged 38-73 years were operated with dura mater interposition technique at our institution between July 1996 and February 2002. In all patients fistula were secondary to abdominal hysterectomies with benign diseases and two had undergone previous transvaginal surgery. Patients were operated 8-15 (mean 12) weeks after previous surgery. A suprapubic cystotomy was performed and the fistula was not excised. The bladder wall is widely dissected from underlying vagina. Dura-mater was placed over the vaginal suture line to close the fistulous tract, cytostomy was inserted and the bladder was closed. An 18 F Foley catheter was left in the bladder for 5 days. A successful repair is defined as no leakage by cystogram at 14 days postoperatively and completely dry by patient report. RESULTS: An overall success rate of 100% was achieved in all patients. All patients remain dry at the follow-up which ranges from 7 to 60 (mean 26) mounts. Patients were discharged at 14 to 26 (mean 16) days postoperatively. No major complications or side effects were observed during the follow-up period. CONCLUSIONS: The use of human dura mater as an interposition graft in the treatment of vesicovaginal fistula is an alternative for VVF repairs because of its excellent tissue compability, stability, good elasticity and absorbability.  相似文献   
39.
OBJECTIVE: We have previously reported a limited but favorable experience with a novel sutureless technique for surgical management of postoperative pulmonary vein stenosis occurring after repair of total anomalous pulmonary venous drainage. Because this technique requires integrity of the retrocardiac space for hemostasis, extension of the technique to the primary repair of pulmonary vein anomalies requires evaluation. This analysis reviews our experience with the sutureless technique in patients with postrepair pulmonary vein stenosis, as well as our extension of the technique into primary repair of pulmonary vein anomalies. METHODS: Retrospective univariable-multivariable analysis of all pulmonary vein stenosis procedures and sutureless pulmonary vein procedures over a 20-year period was performed. Cox proportional hazards modeling was used to identify variables associated with freedom from reoperation or death. RESULTS: Sixty patients underwent 73 procedures, with pulmonary vein stenosis present in 65 procedures. The sutureless technique was used in 40 procedures. Freedom from reoperation or death at 5 years after the initial procedure was 49%. Unadjusted freedom from reoperation or death was greater with the sutureless technique for patients with postrepair pulmonary vein stenosis ( P = .04). By using multivariable analysis, a higher pulmonary vein stenosis score was associated with greater risk of reoperation or death. After adjustment, the sutureless repair was associated with a nonsignificant trend toward greater freedom from reoperation or death ( P = .12). Despite the absence of retrocardiac adhesions, operative mortality was not increased with the sutureless technique ( P = .64). Techniques to control bleeding (intrapleural hilar reapproximation) and improve exposure (inferior vena cava division) were identified. CONCLUSION: The sutureless technique for postrepair pulmonary vein stenosis is associated with encouraging midterm results. Extension of the indications for the technique to primary repair appears safe with the development of simple intraoperative maneuvers.  相似文献   
40.
The aim of this study was to examine the results of different modalities applied in the treatment of 104 fresh diaphyseal fractures of the adult humerus treated in the department between January 1994 and March 1997. These results were classified according to the criteria described by Stewart and Hundley. 32 patients (30.8%) were treated non-operatively using a sling and a moulded plaster splint. The type of treatment had to be changed in 12 of these patients due to 14 different complications that occurred during the course of non-operative treatment. Thus, 20 patients (62.5%) underwent non-operative treatment until fracture-union. The results in this group were: very good in 12 cases (60%), good in 5 cases (25%), fair in 3 cases (15%). 28 fractures were treated using plates and screws. 4 events (14%) occurred during in the post-operative period and, apart from 2 cases of non-union, the overall result in the 26 patients in whom the fracture united was: very good in 23 cases (88.5%) and good in 3 cases (11.5%). 22 patients (21.1%) underwent fixation using multiple flexible intramedullary wires via a supracondylar approach. Apart from one case of non-union, the final result in the 21 patients in whom the fracture united was: very good in 9 cases (42.8%), good in 9 cases (42.8%), fair in 2 cases (9.5%) and poor in 1 case (4.9%). 22 fractures were treated using an intramedullary Seidel nail. The final result in these patients was: very good in 11 cases (50%), good in 9 cases (41%) and poor in 2 cases (9%). The indications for treatment should be eclectic. Non-operative treatment remains the method of choice for undisplaced or minimally-displaced fractures or comminuted fractures with multiple parallel longitudinal fracture-lines over the middle-third, while surgical treatment is considered for displaced fractures and essentially depends upon the type and level of the fracture. Transverse and short oblique fractures are treated using a plate or a Seidel nail. Fractures with a third fragment require plate osteosynthesis. Multiple flexible intramedullary wires are used for segmental fractures or for diaphyseal fractures associated with fractures of the neck of the humerus. Comminuted fractures are realigned using an intramedullary Seidel nail or multiple flexible wires. As far as the site of fracture is concerned, those of the proximal and middle thirds of the humerus are well treated using an intramedullary nail or multiple wires or with a plate, while plating is most often the method of choice for fractures of the distal-third.  相似文献   
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