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71.
The Dunning H rat prostate tumor (R3327H) is a widely used experimental model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been characterized as androgen-sensitive, androgen-receptor (AR) positive, prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To date, the tumor has been maintained by serial passage in vivo because of the lack of an in vitro cell line that retains the characteristics of the in vivo tumor. The objective of the present study was to establish a propagable cell line from R3327H adenocarcinoma that maintained androgen sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in vivo R3327H tumor was dissociated with collagenase and placed into Richter's improved media (with supplements). A cytokeratin-positive epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line (HUNC-S) were generated from the primary culture, subcultured continuously for >300 days, and passaged >50 times. Survival of the HUNC-E cell line in vitro depended on several media supplements, including nicotinamide, insulin, transferrin, selenium and epidermal growth factor (EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the culture period, as confirmed by immunocytochemistry and Western blot analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT) to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent growth and PSA production, which demonstrated the androgen-sensitive nature of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1 ratio and introduced subcutaneously into syngeneic male hosts, tumors formed in 2/3 animals with an average latency of 7 months. RT-PCR and immunocytochemical characterization of the HUNC cell lines revealed that the cells expressed several growth factors and their cognate receptors, including HGF, TGF-alpha and the TGF-betas, indicating the establishment of potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S CaP cell lines, which retain the characteristics of the epithelial and stromal components of the in vivo R3327H tumor, will allow a more thorough and informative molecular and biological analysis of prostatic adenocarcinoma.   相似文献   
72.
A study was carried out to find out the effects of prior physical activity, sports participation and prior military training on the incidence of stress fractures among Gentlemen Cadets (GC''s) undergoing military training at Indian Military Academy (IMA). One thousand and fourteen GC''s were followed up for a period of 12 weeks. Thirty-seven GC''s developed stress fractures during the study period. The incidence of stress fractures was significantly higher in GC''s without any prior military training (p=0.0009). They were compared with 100 healthy controls drawn from the study population to study the influence of the other mentioned factors. There was no significant association between prior physical activity and stress fractures (OR=0.74, 95% CL=0.26 to 2.05, p=0.688). There was also no significant relationship between sports participation and stress fractures (OR=0.79. 95% CCL=0.35 to 1.81, p=0.684).KEY WORDS: Risk factors, Stress fractures  相似文献   
73.
Comparing MR imaging and CT in the staging of gastric carcinoma   总被引:49,自引:0,他引:49  
OBJECTIVE: The purpose of this study was to assess the usefulness of breath-hold two-dimensional (2D) fast low-angle shot (FLASH) and T2-weighted turbo spin-echo fast MR imaging compared with helical CT in the staging of gastric carcinoma. SUBJECTS AND METHODS: Thirty patients with gastric carcinoma underwent preoperative MR imaging and helical CT. MR imaging at 1.5 T was performed immediately after the intramuscular injection of scopolamine and the oral administration of water or effervescent granules. Breath-hold 2D FLASH T1-weighted images in all three planes, turbo spin-echo T2-weighted axial images, and gadolinium-enhanced fat-suppressed 2D FLASH axial images were included. Helical CT was performed 60 sec after initiation of i.v. contrast medium injection (2.5-3 ml/sec). Two groups of two radiologists each independently analyzed the MR and helical CT findings, and these results were compared with the pathologic findings. RESULTS: For T staging, MR imaging accuracy was higher than that of helical CT (73.3% and 66.7%, respectively); however, the accuracies of the two methods were not significantly different from each other (McNemar test, p > 0.05). Overstaging was noted in 6.7% of cases with MR imaging and 10% with helical CT. Understaging was noted in 20% of cases with MR imaging and 23.3% with helical CT. For N staging, the accuracies of MR imaging and helical CT were 55% and 58.6%, respectively, with no statistical significance (overstaging, 10% and 6.9%; understaging, 34.5% and 34.5%, respectively). CONCLUSION: MR imaging was comparable to helical CT in the T and N staging of gastric cancer.  相似文献   
74.
BACKGROUND: Idiopathic adhesive capsulitis is a commonly recognized but poorly understood cause of a painful and stiff shoulder. Although most orthopaedic literature supports treatment with physical therapy and stretching exercises, some studies have demonstrated late pain and functional deficits. The purpose of this study was to evaluate the outcome of patients with idiopathic adhesive capsulitis who were treated with a stretching-exercise program. METHODS: Seventy-five consecutive patients (seventy-seven shoulders) with phase-II idiopathic adhesive capsulitis were treated with use of a specific four-direction shoulder-stretching exercise program and evaluated prospectively. The initial evaluation included the recording of a detailed medical and orthopaedic history and assessment of pain, range of motion, and function. The outcome evaluation included assessment of pain, range of motion, and function; completion of the Disabilities of the Arm, Shoulder, and Hand (DASH) Questionnaire; and completion of the Short Form-36 (SF-36) Health Survey. The mean duration of follow-up was twenty-two months (range, twelve to forty-one months). One patient died prior to the final evaluation, and three patients were lost to follow-up. RESULTS: Sixty-four (90 percent) of the patients reported a satisfactory outcome. Seven (10 percent) were not satisfied with the outcome, and five (7 percent) underwent manipulation and/or arthroscopic capsular release. The outcomes of the patients who did not have manipulation or capsular release were evaluated. There were significant improvements in the scores for pain at rest (from a mean of 1.57 points before treatment to a mean of 1.16 points at the final evaluation; p < 0.001) and pain with activity (from a mean of 4.12 points before treatment to a mean of 1.33 points at the final evaluation; p < 0.0001). On the average, active forward elevation increased 43 degrees, active external rotation increased 25 degrees, passive internal rotation increased eight vertebral levels, and the glenohumeral rotation arc at 90 degrees of abduction increased 72 degrees (p < 0.00001). The number of "yes" responses to the Simple Shoulder Test increased from a mean of 4.1 (of a possible twelve) to a mean of 10.75 (p < 0.00001). Despite the significant improvements and the high rate of patient satisfaction, there were still significant differences in the pain and motion of the affected shoulder when compared with those of the unaffected, contralateral shoulder (p < 0.00001). At the final outcome evaluation, the DASH scores demonstrated limitations when compared with known population norms, whereas the profiles of the SF-36 were comparable with those of age and gender-matched control populations. Prior treatment with physical therapy and a Workers' Compensation claim or pending litigation were the only variables that were associated with the eventual need for manipulation or capsular release. Male gender and diabetes mellitus were associated with worse motion at the final evaluation. Patients with a greater severity of pain with activity at the initial evaluation had significantly lower DASH scores at the final evaluation, and patients with lower initial scores on the Simple Shoulder Test had comparatively lower scores on the Simple Shoulder Test at the outcome evaluation. CONCLUSIONS: The vast majority of patients who have phase-II idiopathic adhesive capsulitis can be successfully treated with a specific four-direction shoulder-stretching exercise program. Although measurable limitations and deficiencies were noted at the outcome evaluation, these appeared to be acceptable to most of the patients and did not affect their general health status. Patients with more severe pain and functional limitations before treatment had relatively worse outcomes. More aggressive treatment such as manipulation or capsular release was rarely necessary, and the efficacy of early use of these treatments should be further studied.  相似文献   
75.
76.
PURPOSE: The purpose of this work was to describe the changes of primary tumor and mediastinal lymph nodes on CT after neoadjuvant concurrent chemoradiotherapy and to correlate the CT findings with pathology. METHOD: Twenty-one consecutive patients [N2 disease (n = 19) or resectable T4 and N2 disease (n = 2)] with non-small cell lung cancer underwent neoadjuvant concurrent chemoradiotherapy. Changes of primary tumor and mediastinal nodes before and after the therapy were assessed using CT. The CT findings were correlated with pathologic findings. RESULTS: With neoadjuvant therapy, decrease in T stage was achieved in 9 of 21 (43%) patients on CT. On pathology, the remaining tumor consisted mostly of fibrosis and necrosis with little proportion of viable tumor cells (mean volume 17%, range 0-55%). Decrease in nodal stage was achieved in 14 of 21 (67%) patients on pathologic examination. Seven patients had cancer cells in mediastinal lymph nodes: in 6 of 9 (67%) patients with adenocarcinoma and 1 of 12 (8%) patients with squamous cell carcinoma (p = 0.016). CONCLUSION: With neoadjuvant concurrent chemoradiotherapy, the remaining tumor consists mostly of fibrosis or necrosis. Decreased nodal stage on pathology is achieved especially in patients with N2 disease of squamous cell carcinoma. The CT findings of the tumor and mediastinal nodes are not helpful in predicting the pathology after the therapy.  相似文献   
77.
Two new polyketide glycosides jejuketomycins A (1) and B (2), were isolated from a culture of Streptomyces sp. KCB15JA151. Their chemical structures including the absolute configurations were determined by detailed analyses of the NMR and HRMS data and ECD calculations and spectral data. Compounds 1 and 2 possess an unusual 6/6/8 tricyclic ring system. Biological evaluation with the wound healing assay and time-lapse cell tracking analysis revealed that compounds 1 and 2 have significant inhibitory activities against cancer cell migration with low cytotoxicity.

Two new polyketide glycosides jejuketomycins A (1) and B (2), were isolated from a culture of Streptomyces sp. KCB15JA151.  相似文献   
78.
In the search for antiangiogenic agents from medicinal plants used in Vietnam, a methanol extract of the stem barks of Bombax ceiba was found to exhibit a significant antiangiogenic activity on in vitro tube formation of human umbilical venous endothelial cells (HUVEC). Bioactivity-guided fractionation and isolation carried out on this extract afforded lupeol as an active principle. At 50 and 30 microg/mL lupeol showed a marked inhibitory activity on HUVEC tube formation while it did not affect the growth of tumor cell lines such as SK-MEL-2, A549, and B16-F10 melanoma.  相似文献   
79.
The KoreaN Cohort Study for Outcomes in Patients With Chronic Kidney Disease (KNOW-CKD) was launched in 2011 with the support of the Korea Disease Control and Prevention Agency. The study was designed with the aim of exploring the various clinical features and characteristics of chronic kidney disease (CKD) in Koreans, and elucidating the risk factors for CKD progression and adverse outcomes of CKD. For the cohort study, nephrologists at 9 tertiary university-affiliated hospitals participated in patient recruitment and follow-up. Biostatisticians and epidemiologists also participated in the basic design and structuring of the study. From 2011 until 2016, the KNOW-CKD Phase I recruited 2238 adult patients with CKD from stages G1 to G5, who were not receiving renal replacement therapy. The KNOW-CKD Phase II recruitment was started in 2019, with an enrollment target of 1500 subjects, focused on diabetic nephropathy and hypertensive kidney diseases in patients with reduced kidney function who are presumed to be at a higher risk of adverse outcomes. As of 2021, the KNOW-CKD investigators have published articles in the fields of socioeconomics, quality of life, nutrition, physical activity, renal progression, cardiovascular disease and outcomes, anemia, mineral bone disease, serum and urine biomarkers, and international and inter-ethnic comparisons. The KNOW-CKD researchers will elaborate a prediction model for various outcomes of CKD such as the development of end-stage kidney disease, major adverse cardiovascular events, and death.  相似文献   
80.
Ocular complications of paediatric patients with nephrotic syndrome   总被引:2,自引:0,他引:2  
Purpose : To investigate ocular complications arising from nephrotic syndrome and/or its treatments in children. Methods : A cross‐sectional study was conducted in a teaching hospital. A total of 31 paediatric patients with nephrotic syndrome were studied. Comprehensive ophthalmic assessments on best‐corrected visual acuity, intraocular pressure, slit‐lamp and fundus examination were taken. Information regarding histological diagnosis of nephrotic syndrome and its treatment regimen in each patient was reviewed and analysed. Results : Bilateral posterior subcapsular cataracts were detected in three of 29 patients (10.3%) who received steroid therapy. Two had normal vision while one had visual acuity reduced to 6/15 in both eyes. The age of onset of the nephrotic syndrome in these three patients was 2 years, which was significantly younger than those without cataract (5.4 ± 3.2 years, P < 0.001). Three patients (9.7%) had isolated asymptomatic fundal findings of tortuous and dilated retinal vessels. Hypertensive retinopathy was found in one patient (3.2%). No steroid‐induced glaucoma, uveitis, ocular infection, or other eye complications related to the use of steroids or other immunosuppressive agents were noted. Conclusions : Children who have nephrotic syndrome often require prolonged, intermittent high dose of systemic corticosteroid therapy. Paediatricians should be aware of the potential risk of developing steroid‐related complications, especially posterior subcapsular cataract. It appears to have a higher risk when steroid therapy is used in very young patients. Early detection would help to prevent amblyopia development, particularly in the group of immature eyes.  相似文献   
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