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11.
Summary Alcohol induced perivenular fibrosis of terminal hepatic veins (THV) is claimed to be a precursor lesion leading to fibrosis development in man and baboon. The nature and significance of the THV lesions found in four baboons chronically fed with alcohol were studied in liver biopsies obtained during a three year period. The surface of THV wall and the number of mesenchymal cells were assessed with a semi-automatic image analyser. Histologically, THV were characterized as (a) phlebitic, in the presence of an inflammatory cell infiltrate involving the venous wall; (b) oedematous, when the connective tissue of the THV wall was disrupted or dissociated and (c) fibrotic, when perivenular scarring appeared as an increased rim. These lesions were present simultaneously and their intensity and distribution were independent of the duration of alcohol intoxication. Morphometric data obtained from these THV confirmed the thickening of the THV wall (WS/IS in: oedematous 1.05±0.36; phlebitic 1.65±1.04; fibrotic 1.47±0.36); and revealed an increased number of mesenchymal cells in fibrotic (439 m2/cell;p<0.01) and in phlebitic THV (510 m2/cell;p<0.05). A constant relationship was found between phlebitis and the presence of inflammatory infiltrate within the hepatic acini. Fibrotic THV was a less frequent finding and the lesion disappeared in the sequential biopsies of one of the baboons. In conclusion, THV lesions were heterogeneous and the collagen deposition in the THV wall was potentially reversible during the three year alcohol intoxication period, regardless the inflammatory reaction and, thus, did not indicate early irreversible hapatic fibrosis.Dr. Porto was supported by a fellowship from MEC-CAPES, Brazil. A grant for morphometric equipment was obtained from the Fondation pour la Recherche Médicale and from the Societé d'Hépatologie Expérimentale, 77 rue Pasteur, Lyon, France  相似文献   
12.
This paper emphasizes the creation and application of a KIT for the communication of occupational accidents with puncture-cutting objects to the Municipal Health Bureau from the city of Ribeir?o Preto. It is an essential instrument for the health care services directed to all the employees of the Health Units. It also evidences the notification and the beginning of the prevention of occupational diseases, being a highly useful instrument whenever any accident occurs. The creation of this KIT enabled the use of prevention measures regarding occupational diseases, culminating with the mobilization of the chiefs and the staff in order to intensify preventive procedures.  相似文献   
13.
Contribution of 60 patients with primary surface transitional cell tumours of the bladder where nuclear expression of p53 protein was prospectively studied and compared to known prognostic factors in an attempt to find out its role in the development of relapses. An statistically significant relationship was found between the protein expression and cytology, tumoral multifocality, stage, relapse development and tumoral progression. It can be concluded that expression of this protein can be of use as relapse predictor.  相似文献   
14.
OBJECTIVE: To describe the development and validation of the Barriers to Care Questionnaire (BCQ). METHODS: The 39-item BCQ was developed through review of the literature, focus groups, and cognitive interviews of Spanish- and English-speaking parents of children with chronic health conditions. Barriers to care are conceptualized as a multidimensional construct consisting of pragmatics, health knowledge and beliefs, expectations about care, skills, and marginalization. The BCQ was field tested in 3 samples of children with special health care needs (CSHCN). RESULTS: Response rate for the field test was 77.2%. There were minimal missing data (0.08%), no floor effects, and minimal ceiling effects (3.8%, total scale). Internal consistency reliability (alpha) for the BCQ total scale was.95 and subscale alpha ranged from.75 to.91. The BCQ total scale and subscales correlated in the expected direction with validated measures of primary care characteristics and health-related quality of life. BCQ scores were higher (fewer barriers) for children with a primary care physician and for those who reported no problems getting care or foregone care. CONCLUSION: The BCQ is a feasible, reliable, and valid instrument for measuring barriers to care for CSHCN. Its use may inform efforts to support consumer choice, enhance provider accountability, and spur quality improvement.  相似文献   
15.
BackgroundCatheter ablation is a well-established therapy for rhythm control in patients who are refractory or intolerant to anti-arrhythmic drugs (AAD). Less is known about the efficacy of catheter ablation compared with AAD as a first-line strategy for rhythm control in atrial fibrillation (AF).ObjectivesWe aimed to perform a systematic review and meta-analysis of catheter ablation vs. AAD in patients naïve to prior rhythm control therapies.MethodsPubMed, EMBASE, and Cochrane databases were searched for randomized controlled trials that compared catheter ablation to AAD for initial rhythm control in symptomatic AF and reported the outcomes of (1) recurrent atrial tachyarrhythmias (ATs); (2) symptomatic AF; (3) hospitalizations; and (4) symptomatic bradycardia. Heterogeneity was examined with I2statistics. P values of < 0.05 were considered statistically significant.ResultsWe included five trials with 994 patients, of whom 502 (50.5%) underwent catheter ablation. Mean follow-up ranged from one to five years. Recurrences of AT (OR 0.36; 95% CI 0.25-0.52; p<0.001) and symptomatic AF (OR 0.32; 95% CI 0.18-0.57; p<0.001), and hospitalizations (OR 0.25; 95% CI 0.15-0.42; p<0.001) were significantly less frequent in patients treated with catheter ablation compared with AAD. Symptomatic bradycardia was not significantly different between groups (OR 0.55; 95% CI 0.18-1.65; p=0.28). Significant pericardial effusions or tamponade occurred in eight of 464 (1.7%) patients in the catheter ablation group.ConclusionThese findings suggest that catheter ablation has superior efficacy to AAD as an initial rhythm control strategy in patients with symptomatic AF.  相似文献   
16.
SARS-CoV-2 variant detection relies on resource-intensive whole-genome sequencing methods. We sought to develop a scalable protocol for variant detection and surveillance in Paraguay, pairing rRT-PCR for spike mutations with Nanopore sequencing. A total of 201 acute-phase nasopharyngeal samples were included. Samples were positive for the SARS-CoV-2 N2 target and tested with the Spike SNP assay to detect mutations associated with the following variants: alpha (501Y), beta/gamma (417variant/484K/501Y), delta (452R/478K), and lambda (452Q/490S). Spike SNP calls were confirmed using amplicon (Sanger) sequencing and whole-genome (Nanopore) sequencing on a subset of samples with confirmed variant lineages. Samples had a mean N2 Ct of 20.8 (SD 5.6); 198/201 samples (98.5%) tested positive in the Spike SNP assay. The most common genotype was 417variant/484K/501Y, detected in 102/198 samples (51.5%), which was consistent with the P.1 lineage (gamma variant) in Paraguay. No mutations (K417 only) were found in 64/198 (32.3%), and K417/484K was identified in 22/198 (11.1%), consistent with P.2 (zeta). Seven samples (3.5%) tested positive for 452R without 478K, and one sample with genotype K417/501Y was confirmed as B.1.1.7 (alpha). The results were confirmed using Sanger sequencing in 181/181 samples, and variant calls were consistent with Nanopore sequencing in 29/29 samples. The Spike SNP assay could improve population-level surveillance for mutations associated with SARS-CoV-2 variants and inform the judicious use of sequencing resources.  相似文献   
17.
IntroductionOxidative stress (OS) occurs in cystic fibrosis (CF).ObjectiveThe objective of this work is to evaluate the influence of bacterial infection on biomarkers of OS (catalase [CAT], glutathione peroxidade [GPx], reduced glutathione [GSH]), markers of oxidative damage (protein carbonyls [PC], thiobarbituric acid reactive substances [TBARS]), together with the nutritional status and lung function in children with CF.MethodsCross‐sectional study including CF group (CFG, n = 55) and control group (CG, n = 31), median age: 3.89 and 4.62 years, respectively. CFG was distributed into CFG negative bacteriology (CFGB−, n = 27) or CFG positive bacteriology (CFGB+, n = 28), and CFG negative Pseudomonas aeruginosa (CFGPa−, n = 36) or CFG positive Pseudomonas aeruginosa (CFGPa+, n = 19).ResultsCompared with CG, CFG (P = .034) and CFGB+ (P = .042) had lower body mass index‐for‐age z‐score; forced expiratory volume in the first second was lower in CFGB+ and CFGPa+ (both P < .001). After adjusting for confounders and compared with CG: CFG showed higher TBARS (P ≤ .001) and PC (P = .048), and lower CAT (P = .004) and GPx (P = .003); the increase in PC levels was observed in CFGB+ (P = .011) and CFGPa+ (P = .001) but not in CFGB− (P = .510) and CFGPa− (P = .460).ConclusionsThese results indicate a systemic OS in children with CF. The presence of bacterial infection particularly Pseudomonas aeruginosa seems to be determinant to exacerbate the oxidative damage to proteins, in which PC may be a useful biomarker of OS in CF.  相似文献   
18.
19.
Neuroendocrine carcinoma of the larynx   总被引:1,自引:0,他引:1  
Neoplasms of the larynx showing neuroendocrine differentiation are uncommon, with less than 100 previously reported cases. These tumors encompass subcategories that have been designated heretofore as "malignant carcinoid" and "oat cell carcinoma" and have been associated with ectopic production of neuropeptides and biogenic amines. We report a case of neuroendocrine carcinoma that arose in the epiglottis in an elderly man, metastasized widely, and was responsible for death. Immunohistochemical studies showed the presence of serotonin, calcitonin, ACTH, met-enkephalin, chromogranin, and neuron-specific enolase within tumor cells, although clinical endocrinopathy was absent. This case is used as a focus for discussion of the spectrum of neuroendocrine tumors of the head and neck, including recommended treatment approaches for such neoplasms.  相似文献   
20.
OBJECTIVE: To estimate how well a convenience sample of women from the general population could self-screen for contraindications to combined oral contraceptives using a medical checklist. METHODS: Women 18-49 years old (N=1,271) were recruited at two shopping malls and a flea market in El Paso, Texas, and asked first whether they thought birth control pills were medically safe for them. They then used a checklist to determine the presence of level 3 or 4 contraindications to combined oral contraceptives according to the World Health Organization Medical Eligibility Criteria. The women then were interviewed by a blinded nurse practitioner, who also measured blood pressure. RESULTS: The sensitivity of the unaided self-screen to detect true contraindications was 56.2% (95% confidence interval [CI] 51.7-60.6%), and specificity was 57.6% (95% CI 54.0-61.1%). The sensitivity of the checklist to detect true contraindications was 83.2% (95% CI 79.5-86.3%), and specificity was 88.8% (95% CI 86.3-90.9%). Using the checklist, 6.6% (95% CI 5.2-8.0%) of women incorrectly thought they were eligible for use when, in fact, they were contraindicated, largely because of unrecognized hypertension. Seven percent (95% CI 5.4-8.2%) of women incorrectly thought they were contraindicated when they truly were not, primarily because of misclassification of migraine headaches. In regression analysis, younger women, more educated women, and Spanish speakers were significantly more likely to correctly self-screen (P<.05). CONCLUSION: Self-screening for contraindications to oral contraceptives using a medical checklist is relatively accurate. Unaided screening is inaccurate and reflects common misperceptions about the safety of oral contraceptives. Over-the-counter provision of this method likely would be safe, especially for younger women and if independent blood pressure screening were encouraged.  相似文献   
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