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81.
OBJECTIVE: To examine the regional differences in the functional (pharmacological) and biochemical properties of endothelin (ET) receptors in the rabbit prostatic urethra. MATERIALS AND METHODS: The properties of ET receptors in 6-month-old male rabbit prostatic urethras were examined using isolated muscle-bath and radioligand receptor-binding techniques. Using plasma membrane suspensions, saturation and inhibition experiments with [(125)I]ET-1 and unlabelled agonists and antagonists (ET(A)-selective antagonist BQ123, and ET(B)-selective agonist sarafotoxin 6c, STX6c) were done to determine the ET receptor densities and their subtype specificities in the different regions of the urethra. RESULTS: The ETs (ET-1 and ET-3) produced significant concentration-dependent contractile responses in the smooth muscle strips from the different regions of the urethra. Although the maximum contractile responses induced by ET-1 were similar in the different regions, the maximum contractile responses induced by ET-3 were greater in the distal region than in the proximal or middle regions, suggesting that the contractile response to ET-1 is more potent than that to ET-3 in all regions, and that there are region-specific differences in the responses to ET-3 but not ET-1. Moreover, the ET-3-induced contractile response was suppressed by BQ788 (a selective antagonist of the ET(B) receptor) suggesting that the ET(B) receptor subtype contributes to the contractile responses mediated by ET-3. The ET receptors were expressed in higher concentrations in the distal than in the proximal or middle regions. BQ123 and STX6c inhibited [(125)I]ET-1 binding in all regions with high and low affinity constants, indicating the presence of both ET(A) and ET(B) receptor subtypes. The proportions of high-affinity binding sites for BQ123, representing ET(A) receptors, were approximately 68%, 63% and 42% in the proximal, middle and distal regions, respectively. By contrast, the proportions of high-affinity binding sites for STX6c, representing ET(B) receptors, were approximately 27%, 35% and 52% in the proximal, middle, and distal regions, respectively. These data indicate the presence of regional differences in the densities and subtype specificities of ET receptor subtypes, and the existence of regional differences in the rabbit prostatic urethra. CONCLUSION: The results suggest regional differences in ET(B) receptor subtypes that mediate contractile responses to ET-3, reflecting differences in the densities and specificities of the ET receptor subtypes in the rabbit prostatic urethra.  相似文献   
82.
The goal of this study was to evaluate the efficacy of Alpha ointment in the treatment of burn wounds and compare its results with silver sulfadiazine (SS). Similar burn ulcers were produced on anterior surface of thigh of 60 rats. The wounds were infected with Pseudomonas aeruginosa and dressing and debridement was performed daily. The first group of rats received topical SS, the second group received Alpha ointment and the third (control group) received no medication. Wound healing, contraction, culture, and scar formation were evaluated at the end of the second and 10th week. Alpha ointment was equally effective as SS, considering wound healing and contraction. Wound infection was significantly less common in Alpha ointment group compared to the other two groups (p<0.05). Alpha ointment is a less expensive drug with an acceptable result compared to SS. Therefore, we recommend it as an alternative to SS, especially in patients with low economical backgrounds or in those who show adverse reactions to SS.  相似文献   
83.
BACKGROUND: Survey studies are of limited utility in estimating the prevalence of treated dry eye. The use of claims data, which include only individuals who have a diagnosis of the disorder, provides a better estimation of the clinical significance of dry eye symptoms and appraisal of community needs. OBJECTIVE: The purpose of this paper is to estimate the prevalence of treated dry eye disease using a nonsurvey methodology. METHODS: Patients with dry eye diagnoses or who underwent punctal occlusion procedures were identified from PharMetrics' Integrated Outcomes database of medical claims for approximately 10 million patients enrolled in managed care plans. Prevalence estimates were calculated for 1997 and 1998. RESULTS: The prevalence of dry eye was 0.48% in 1997 and 0.39% in 1998, representing 25,180 and 27,289 cases, respectively. Patients aged > or = 65 years were approximately 4 times as likely as those aged < 65 years to be diagnosed with keratoconjunctivitis sicca or tear film insufficiency. In 1997, dry eye was diagnosed or treated in 0.65% of women compared with 0.26% of men (P < 0.001). Rates of dry eye disease in 1998 were highest among women aged 75 to 79 years (2.02%) and men aged 80 to 84 years (1.30%). Women tended to receive a diagnosis at a younger age than did men. The most common diagnosis was tear film insufficiency (73.96% and 73.41% of dry eye patients in 1997 and 1998, respectively). The most common procedure was lacrimal punctal occlusion by plug (7.78% and 8.74% of dry eye patients in 1997 and 1998, respectively). CONCLUSION: The prevalence of treated dry eye disease is 0.4% to 0.5% and is highest among women and the elderly.  相似文献   
84.
Of 836 medical admissions evaluated over a 1-month period, 89 (10.7%) had a urinary catheter placed within 24 hours; 34 placements (38%) had no justifiable indication. Risk for inappropriate catheterization was independent of age, gender, functional status, and mental status at admission. Preventive measures should focus on increasing awareness among healthcare providers.  相似文献   
85.
86.
Background. Stress perfusion imaging can assess effectively the amount of jeopardized myocardium, but its use for identifying underperfused but viable myocardium has yielded variable results. We evaluated the relation between measurements of myocardial perfusion at rest and during pharmacologic stress and the patterns of tissue viability as determined by positron emission tomographic (PET) imaging.Methods and Results. We studied 33 patients with coronary artery disease and left ventricular (LV) dysfunction (LV ejection fraction, 30% ± 8%). PET imaging was used to evaluate regional myocardial perfusion at rest and during pharmacologic stress with [13N]-ammonia as a flow tracer, and to delineate patterns of tissue viability (ie, perfusion-metabolism mismatch or match) using [18F]-deoxyglucose (FDG). We analyzed 429 myocardial regions, of which 229 were dysfunctional at rest. Of these, 30 had normal perfusion and 199 were hypoperfused. A severe resting defect (deficit>40% below normal) predicted lack of significant tissue viability; 31 of 35 regions (89%) had a PET match pattern denoting transmural fibrosis. Although regions with mild or moderate resting defects (deficit <40% below normal) showed evidence of metabolic activity, perfusion measurements alone failed to identify regions with PET mismatch (reflecting hibernating myocardium). Reversible stress defects were observed with slightly higher frequency in regions with a PET mismatch (10 of 37) than in those with a PET match (36 of 162) pattern of viability. A reversible stress defect was a specific (78%) marker, but was a relatively insensitive marker (27%) of viable myocardium as defined by the PET mismatch pattern.Conclusions. In patients with LV dysfunction, the severity of regional contractile abnormalities correlates with the severity of flow deficit at rest. Severe reductions in resting blood flow in these dysfunctional regions identify predominantly nonviable myocardium that is unlikely to have improved function after revascularization. Although dysfunctional myocardium with mild to moderate flow reductions contains variable amounts of viable tissue (as assessed by FDG uptake), flow measurements alone do not distinguish between regions with PET mismatch (potentially reversible dysfunction) and PET match (irreversible dysfunction). The presence of an irreversible defect on stress imaging is a relatively specific (78%) marker of PET match, whereas a reversible stress defect is a rather insensitive (27%) marker of viability, as defined by the PET mismatch pattern.  相似文献   
87.

Objective

To explore factors influencing how well-informed women felt about hysterectomy, influences on their decision making, and on them receiving a less-invasive alternative to open surgery.

Methods

Online questionnaire, conducted in 2015–2016, of women who had received a hysterectomy in Australia, in the preceding two years.

Results

Questionnaires were completed by 2319/6000 women (39% response). Most women (n = 2225; 96%) felt well-informed about hysterectomy. Women were more aware of the open abdominal approach (n = 1798; 77%), than of less-invasive vaginal (n = 1552; 67%), laparoscopic (n = 1540; 66%), laparoscopic-assisted (n = 1303; 56%), and robotic approaches (n = 289; 12%). Most women (n = 1435; 62%) reported their gynaecologist was the most influential information source. Women who received information about hysterectomy from a GP (OR = 1.47; 95% CI 1.15-1.90), or from a gynaecologist (OR = 1.3; 95% CI 1.06-1.58), were more likely to feel better informed (p < 0.01).

Conclusion

This study is important because it helps clinicians, researchers and health policy makers to understand why many women still receive an open abdominal approach despite many learned societies recommending to avoid it if possible.

Practice implications

Additional information, or education about avoiding open abdominal approach where possible may lead to a greater number of women receiving less-invasive types of hysterectomy in the future.  相似文献   
88.
The cervical spine, supporting such critical structures as the medulla, spinal cord, and cervical nerve roots, can be very challenging to image propertly because of its complex structural anatomy and superimposition of bony and soft tissue parts. In this article, the use and value of the various modalities that image the cervical spine are discussed. Plain radiography remains the best screening tool in the initial evaluation of the cervical spine after trauma. Additional views, such as swimmer's, pillar and lateral flexion, and extension, often are helpful in certain circumstances.  相似文献   
89.
90.
Common variable immunodeficiency (CVID) is the most frequent symptomatic primary immunodeficiency disease, and its prevalence varies significantly among different population. Minority of CVID patients present a familial aggregation suggesting a higher probability of heritable genetic defects. A total of 235 registered CVID patients were evaluated in this cohort study. Familial and sporadic patients were stratified, and demographic information, clinical records, laboratory and molecular data were compared among these two groups of patients. Multiple cases were identified in 12 families (30 patients) and sporadic presentation in 120 cases. The rate of parental consanguinity (83.3%) and clinical presentation of lymphoid malignancy (20.7%) were predominant in familial CVID patients, whereas significantly increased recurrent upper respiratory infections were recorded in sporadic patients (0.3 infections per year). Probands of familial group were presented with a higher severity score resulting in a profound mortality rate (41.7% after 30‐year follow‐up) comparing to the non‐proband CVID patients in the same families with a lowered diagnostic delay. Familial CVID patients had a specific signature in clinical presentation and immunologic profile, and a high consanguinity in this group of patients suggests a Mendelian trait with an autosomal recessive inheritance pattern. Diagnosis of an index patient within a multiple case families significantly improves the diagnostic process and outcomes of the yet asymptomatic patients.  相似文献   
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