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111.
In these studies, we have used an allergic rabbit model to investigate the role of platelets in the late asthmatic response (LAR) by depleting platelets with a guinea pig antirabbit platelet antiserum (APAS). Allergen exposure of immunized rabbits pretreated with normal guinea pig serum (NGPS) to serve as a control resulted in an early- and late-phase obstructive airway response that persisted for 6 h. When the immunized animals were pretreated with APAS, the magnitude of the LAR in terms of dynamic compliance was reduced by 86.2% (p less than 0.03), but there was no difference in the early response curve. Allergen challenge of animals treated with NGPS resulted in an increased bronchial responsiveness to inhaled histamine: PD50 Cdyn geometric mean +/- SEM before, 2.36 mg/ml (3.43-1.64); after, 0.60 mg/ml (0.67-0.54) (p less than 0.01). PD50 RL before, 1.78 mg/ml (2.4-1.32); after, 0.58 mg/ml (0.81-0.47) (p less than 0.05). In contrast, when animals were treated with APAS, there was a significant inhibition of allergen-induced airway hyperresponsiveness to inhaled histamine: PD50 Cdyn geometric mean +/- SEM before, 1.42 mg/ml (2.06-0.98); after, 1.10 mg/ml (1.41-0.86) (p less than 0.4). PD50 RL before, 1.62 mg/ml (2.22-1.39); after, 1.05 mg/ml (1.35-0.82) (p greater than 0.4). Analysis of bronchoalveolar lavage fluid revealed an increase in the number of neutrophils and eosinophils after allergen exposure in control animals (p less than 0.01). However, in animals rendered thrombocytopenic, the number of eosinophils, but not neutrophils, was significantly reduced (p less than 0.03).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
112.
Clinical role of bronchoalveolar lavage in adults with pulmonary disease   总被引:3,自引:0,他引:3  
BAL remains a powerful investigative tool. In a short span of 20 yr, it has helped tremendously in understanding some of the aspects of the pathogenesis of diseases involving the lower respiratory tract. To realize its full potential in the diagnosis and management of diseases involving the lower respiratory tract, there is a great need for standardization of the technical aspects of BAL as well as processing and analysis of the BAL cellular- and fluid-phase components. Despite these hurdles, BAL has been found to be diagnostic in several infectious and noninfectious diseases involving the lower respiratory tract, and it provides valuable information that may be helpful in characterizing the prognosis and response to therapy in certain interstitial diseases of the lung. It is expected that with future research, in particular long-term prospective epidemiologic and clinical studies in pneumoconioses and in other interstitial lung disease, BAL will prove more valuable in the diagnosis and management of such disease.  相似文献   
113.
The lateral habenula (LHb) is an epithalamic structure differentiated in a medial (LHbM) and a lateral division (LHbL). Together with the rostromedial tegmental nucleus (RMTg), the LHb has been implicated in the processing of aversive stimuli and inhibitory control of monoamine nuclei. The inhibitory LHb influence on midbrain dopamine neurons has been shown to be mainly mediated by the RMTg, a mostly GABAergic nucleus that receives a dominant input from the LHbL. Interestingly, the RMTg also projects to the dorsal raphe nucleus (DR), which also receives direct LHb projections. To compare the organization and transmitter phenotype of LHb projections to the DR, direct and indirect via the RMTg, we first placed injections of the anterograde tracer Phaseolus vulgaris leucoagglutinin into the LHb or the RMTg. We then confirmed our findings by retrograde tracing and investigated a possible GABAergic phenotype of DR‐projecting RMTg neurons by combining retrograde tracing with in situ hybridization for GAD67. We found only moderate direct LHb projections to the DR, which mainly emerged from the LHbM and were predominantly directed to the serotonin‐rich caudal DR. In contrast, RMTg projections to the DR were more robust, emerged from RMTg neurons enriched in GAD67 mRNA, and were focally directed to a distinctive DR subdivision immunohistochemically characterized as poor in serotonin and enriched in presumptive glutamatergic neurons. Thus, besides its well‐acknowledged role as a GABAergic control center for the ventral tegmental area (VTA)–nigra complex, our findings indicate that the RMTg is also a major GABAergic relay between the LHb and the DR. J. Comp. Neurol. 522:1454–1484, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
114.
It is highly recommended to conduct a prophylactic check for any dental problems on patients who suffer from leukaemia before chemotherapy begins. Bacteraemia caused by oral microflora may be very dangerous for patients with haematological malignancies. However, it should be noted that the prophylactic process itself might bring about life-threatening complications if there is only a short interval between dental treatment and the beginning of chemotherapy, or if the dental treatment is too aggressive. We present a case where this prophylactic procedure produced life-threatening complications for a patient with acute myeloid leukaemia.  相似文献   
115.
Pulmonary histiocytosis X: comparison of radiographic and CT findings   总被引:6,自引:0,他引:6  
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities.  相似文献   
116.
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein.  相似文献   
117.
Abstract

Background/Objective: Motor vehicle collision (MVC)-related spinal cord injury (SCI) is the mostprevalent etiology of SCI. Few studies have defined SCI risk factors. Vehicle mismatch occurs in 2-vehicleMVCs in which there are significant differences in vehicle weight, stiffness, and height. This study examinedSCI risk and vehicle mismatch.

Methods: A matched case-control study using the 1995 to 2003 National Automotive Sampling System(NASS). Study subjects were identified from 2-vehicle MVCs. Cases were occupants who had suffereda cervical, thoracic, or lumbar SCI. Odds ratios (ORs) and 95% confidence intervals (Cis) were calculated.

Results: There were 101,682 cases of SCI matched to 805,091 controls. Occupants of passenger vehiclesinvolved in MVCs with a light truck or van (LTV) were at increased risk for SCI (OR= 1.87, 95% Cl= 1.07-3.24) and this risk was greatest for thoracic SCI (OR= 5.09, 95% Cl= 2.33-11.13). In addition, occupants ofL TVs involved in MVCs with passenger vehicles were at significant increased risk for cervical (OR= 1. 39) andlumbar (OR= 2.65) SCI; and occupants of LTVs involved in MVCs with other LTVs were at increased risk ofany SCI (OR= 2.02, 95% Cl= 1.52-2.69). For these subjects, significant increased risks were seen for all spineregions: cervical (OR= 1.41), thoracic (OR= 2.86), and lumbar (OR= 2.38).

Conclusions: The results of this study suggest that occupants of passenger vehicles are at increased SCI riskwhen involved in 2-vehicle MVCs with L TVs; and that occupants of L TVs are at increased SCI risk, regardless  相似文献   
118.
BACKGROUND: Past studies have identified surgeon- and institution- related characteristics as prognostic factors in colorectal cancer surgery. The present work assesses the influence of the surgeon's and the hospital's caseload on long-term results of colorectal cancer surgery. METHODS: The data on 2706 patients from 2, randomized, colorectal cancer trials (Swiss Group for Clinical Cancer Research [SAKK] 40/81, SAKK 40/87) investigating adjuvant intraportal and systemic chemotherapy and 1 concurrent registration study (SAKK 40/88) were reviewed. A first analysis included 1809 eligible, nonmetastatic patients from all 3 studies. A subsequent subgroup analysis included 915 eligible patients from both randomized trials. Overall survival (OS), disease-free survival (DFS), and local recurrence (LR) were analyzed in multivariate models taking into account the possible effect of clustering. The main potential covariates were surgeon's annual caseload (>5 operations/year vs < or =5 operations/year), hospital's annual caseload (>26 operations/year vs < or =26 operations/year), tumor site, T stage, and nodal status. RESULTS: Primary analysis of all 3 studies combined found a high surgeon's caseload to be positively associated with OS (P = .025) and marginally with DFS (P = .058). Separate analysis for each trial, however, showed that a high surgeon's caseload was beneficial for outcome in both randomized trials but not in the registration study. A subgroup analysis of 915 patients with 376 rectal and 539 colonic primaries from both randomized trials, therefore, was performed. Neither age, gender, year of operation, adjuvant chemotherapy (intraportal vs systemic vs operation alone), hospital academic status (university vs non-university), training status of the surgeon (certified surgeon vs surgeon-in-training), nor inclusion in 1 of the 2 randomized trials (SAKK 40/81 vs SAKK 40/87) was a significant predictor of outcome. However, both high surgeon's and high hospital's annual caseloads were independent, beneficial prognostic factors for OS (P = .0003, P = .044) and DFS (P = .0008, P = .020), and marginally significant factors for LR (P = .057, P = .055). CONCLUSIONS: High surgeon's and hospital's annual caseloads are strong, independent prognostic factors for extending overall and disease-free survival and reducing the rate of local recurrence in 2 randomized colorectal cancer trials.  相似文献   
119.

Background

The role of laparoscopy in the setting of perforated appendicitis remains controversial. A retrospective study was conducted to evaluate the early postoperative outcomes of laparoscopic appendectomy (LA) compared to open appendectomy (OA) in patients with perforated appendicitis.

Methods

A total of 1,032 patients required an appendectomy between January 2005 and December 2009. Among these patients, 169 presented with perforated appendicitis. Operation times, length of hospital stay, overall complication rates within 30 days, and surgical site infection (SSI) rates were analyzed.

Results

Out of the 169 evaluated patients, 106 required LA and 63 OA. Although operation times were similar in both groups (92 ± 31 min for LA vs. 98 ± 45 for OA, p = 0.338), length of hospital stay was shorter in the LA group (6.9 ± 3.8 days vs. 11.5 ± 9.2, p < 0.001). Overall complication rates were significantly lower in the LA group (32.1 vs. 52.4 %, p < 0.001), as were incisional SSI (1.9 vs. 22.2 %, p < 0.001). Organ/space SSI rates were similar in both groups (23.6 % after LA vs. 20.6 % after OA, p = 0.657).

Conclusions

For perforated appendicitis, LA results in a significantly shorter hospital stay, fewer overall postoperative complications, and fewer wound infections compared to OA. Organ/space SSI rates were similar for both procedures. LA provides a safe option for treating patients with perforated appendicitis.  相似文献   
120.
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