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51.
OBJECTIVE: To determine the clinical and epidemiologic characteristics of patients with sepsis admitted to hospitals in Victoria, Australia, including the incidence of sepsis and severe sepsis, utilization of intensive care unit (ICU) resources, and hospital mortality. DESIGN: A population-based hospital morbidity database generated from hospital discharge coding. SETTING: State of Victoria, Australia (population, 4.5 million), the 4-yr period from July 1, 1999, to June 30, 2003. PATIENTS: A total of 3,122,515 overnight hospitalizations. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The overall hospital incidence of sepsis was 1.1%, with a mortality of 18.4%. Of septic patients, 23.8% received some care in an ICU. For these patients, hospital mortality was 28.9%. Severe sepsis, defined by sepsis and at least one organ dysfunction, occurred in 39% of sepsis patients and was accompanied by a hospital mortality of 31.1%. Fifty percent of patients with severe sepsis received at least some care in an ICU. CONCLUSIONS: Australian state hospital administrative data reveal epidemiologic features of sepsis and severe sepsis that are strikingly similar to those recently reported from comparable populations in North American and Europe. This suggests that lessons learned in this area may be directly applicable internationally.  相似文献   
52.
Neural classification of lung sounds using wavelet coefficients   总被引:6,自引:0,他引:6  
Electronic auscultation is an efficient technique to evaluate the condition of respiratory system using lung sounds. As lung sound signals are non-stationary, the conventional method of frequency analysis is not highly successful in diagnostic classification. This paper deals with a novel method of analysis of lung sound signals using wavelet transform, and classification using artificial neural network (ANN). Lung sound signals were decomposed into the frequency subbands using wavelet transform and a set of statistical features was extracted from the subbands to represent the distribution of wavelet coefficients. An ANN based system, trained using the resilient back propagation algorithm, was implemented to classify the lung sounds to one of the six categories: normal, wheeze, crackle, squawk, stridor, or rhonchus.  相似文献   
53.
BACKGROUND: The optimal treatment for patients with stage II ovarian cancer is controversial, although most experts recommend adjuvant chemotherapy. The purpose of this study was to assess the patterns of use of chemotherapy in women with stage II ovarian cancer, and to compare the survival of treated and untreated patients aged 65+ years in a population-based sample. METHODS: Using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database of cancers diagnosed in approximately 14% of the U.S. population, we identified women who were diagnosed with stage II ovarian cancer between 1992 and 1996, survived >or=120 days beyond diagnosis, and were >or=65 years of age. Multivariate regression was used to compare those treated to those not treated with chemotherapy. Cox proportional hazards regression models were used to analyze patient survival. RESULTS: Of 236 women with stage II ovarian cancer, 160 (67.8%) received chemotherapy, and 118 (50%) received platinum-based regimens. Younger patients and those with higher-grade tumors were more likely to receive chemotherapy. The adjusted hazards ratio for mortality associated with any chemotherapy use was 0.67 (95% CI, 0.45-0.98), corresponding to an increase in median survival from 28 months to 35 months (P < 0.0001). CONCLUSIONS: This observational study found that most patients aged >or=65 years and diagnosed with stage II ovarian cancer between 1992 and 1996 were treated with chemotherapy. Grade and younger age were the most significant predictors of treatment, and treatment was associated with a 5-year mortality reduction of 33%. These findings are not definitive, but they may provide some guidance in the absence of randomized trials of adjuvant chemotherapy for older women with stage II ovarian cancer.  相似文献   
54.
BACKGROUND: Platinum-based chemotherapy is the standard of care for women with advanced ovarian cancer based on the results of randomized trials. We previously showed that only about half of women over the age of 65 years with this disease received platinum-based chemotherapy, and that the likelihood of receiving it decreases with age. METHODS: We used the Surveillance, Epidemiology, and End Results (SEER)-Medicare database to identify women diagnosed from 1/1/92 to 12/31/96 with stage III or IV ovarian cancer who survived > or =120 days beyond diagnosis, and were > or =65 years of age. Cox proportional hazards models and propensity scores were used to control for known predictors of receiving treatment and to estimate the relative effectiveness of different platinum-based regimens. RESULTS: Of the 1759 patients in the sample who met our eligibility criteria, 53% received platinum-based therapy. For this sample, the Cox proportional hazard ratio was 0.72 (95% CI, 0.62-0.91) for mortality associated with the use of any platinum-based therapy, and 0.59 (95% CI, 0.45-0.76) for combination platinum/paclitaxel therapy. Similar results were obtained using propensity score modeling. CONCLUSIONS: In this population-based study, we found that only about half of women with advanced ovarian cancer over age 65 were treated with platinum-based chemotherapy; however, survival improved by 38% in treated women, similar to the benefits described in randomized controlled trials among younger patients, and were greatest when platinum was combined with paclitaxel. An effort to increase the utilization of platinum combination therapy among older patients with advanced ovarian cancer is justified.  相似文献   
55.

Purpose

Gastrointestinal (GI) dysmotility occurs frequently in full-term infants with gastroschisis (GS). Although controversial, preterm delivery of infants with GS has been advocated to prevent the development of GI dysmotility, and understanding the etiology of gestational-related bowel injury may lead to prenatal therapies. Using a fetal rabbit model, the authors assessed in vivo and in vitro GI motility in preterm GS fetuses.

Methods

On gestation day 24 (term, 31), surgery was performed in maternal rabbits and GS induced in fetuses, whereas control fetuses underwent sham procedures. On gestation day 29, both groups of fetuses received ultrasound-guided intragastric injection of fluorescein and colored microspheres. Two hours after injection, fetuses were delivered by cesarean section and stomach and small intestine harvested intact. “GI motility” was calculated as the distance traveled by fluorescein divided by total length. In vitro studies of fetal gastric muscle strips contractility responses to bethanechol, a cholinergic agonist, were assessed in an organ bath system. Data were analyzed as paired and unpaired t tests and expressed as means ± SEM.

Results

GS reduced fetal body weight and intestinal length compared with controls (28.4 ± 1.4 v. 33.5 ± 1.5 g, 36.9 ± 1.8 v. 25.9 ± 1.2 cm; P < .05, respectively). Fetuses with GS showed markedly reduced in vivo GI motility (51.4 ± 2.9 v 24.8 ± 2.7%; P < .05) and in vitro gastric contractile tension (769 ± 53 v 396 ± 26 mNcm2; P < .05).

Conclusions

GI exposure to amniotic fluid reduces intestinal motility and gastric contractility functions in the preterm rabbit fetus. The results suggest that GS-associated impairment of GI neuromuscular functions occurs in utero, before term, and may be responsive to manipulation of amniotic fluid content or other therapeutic interventions.  相似文献   
56.
PURPOSE: To prospectively compare the effectiveness of multi-detector row computed tomographic (CT) angiography with that of conventional intraarterial digital subtraction angiography (DSA) used to detect intracranial aneurysms in patients with nontraumatic acute subarachnoid hemorrhage. MATERIALS AND METHODS: Thirty-five consecutive adult patients with acute subarachnoid hemorrhage were recruited into the institutional review board-approved study and gave informed consent. All patients underwent both multi-detector row CT angiography and DSA no more than 12 hours apart. CT angiography was performed with a multi-detector row scanner (four detector rows) by using collimation of 1.25 mm and pitch of 3. Images were interpreted at computer workstations in a blinded fashion. Two radiologists independently reviewed the CT images, and two other radiologists independently reviewed the DSA images. The presence and location of aneurysms were rated on a five-point scale for certainty. Sensitivity and specificity were calculated independently for image interpretation performed by the two CT image readers and the second DSA image reader by using the first DSA reader's interpretation as the reference standard. RESULTS: A total of 26 aneurysms were detected at DSA in 21 patients, and no aneurysms were detected in 14 patients. Sensitivity and specificity for CT angiography were, respectively, 90% and 93% for reader 1 and 81% and 93% for reader 2. The mean diameter of aneurysms detected on CT angiographic images was 4.4 mm, and the smallest aneurysm detected was 2.2 mm in diameter. Aneurysms that were missed at initial interpretation of CT angiographic images were identified at retrospective reading. CONCLUSION: Multi-detector row CT angiography has high sensitivity and specificity for detection of intracranial aneurysms, including small aneurysms, in patients with nontraumatic acute subarachnoid hemorrhage.  相似文献   
57.
Ischemic disease is a leading cause of death and disability worldwide, and its incidence is expected to increase as the population ages. One population at particularly high risk of developing ischemia is patients with diabetes. Type 2 diabetes is associated with a marked increase in atherosclerosis, stroke and heart attack. Furthermore, the outcome following stroke and heart attack in diabetics is worse than in nondiabetic patients. In recent years, peroxisome proliferator-activated receptor (PPAR) agonists have been found to have potent antiinflammatory actions and have emerged as potential therapies for atherosclerosis and ischemia. The use of these agents is particularly attractive, since two PPARgamma agonists, pioglitazone (Actos) and rosiglitazone (Avandia), are already used chronically to treat diabetes. In this article we review the role of inflammation in ischemic disease and the biology of PPARs, and summarize the evidence that PPARgamma ligands suppress inflammation with an emphasis on atherosclerosis, and cerebral and myocardial ischemia.  相似文献   
58.
59.
OBJECTIVE: In the preterm human fetus, immaturity of gastrointestinal (GI) motility contributes to impairment of oral feeding and an increased risk of necrotizing enterocolitis. In view of the limited knowledge of fetal GI motility development, and the primary role of the muscarinic system in adult GI motility, we examined the development of GI muscarinic receptor subtypes associated with ileal motility. STUDY DESIGN: Ovine term fetal, newborn, and pregnant adult ileal longitudinal muscle contractile responses to muscarinic agonists (bethanechol) and muscarinic nonspecific (atropine) and subtype specific-antagonists (M1-M4) were examined in organ baths. Immunohistochemical analysis of ileal muscle muscarinic receptor subtypes was correlated with contractile responses. RESULTS: Bethanechol induced a concentration-dependent ileal contraction at all 3 age groups. Adult ileal maximal tension was 2-fold higher than that of the fetus and newborn, while 50% effective concentration (EC(50)) was similar at all ages. Atropine (10(-6)mol/L) inhibited contractility in fetal (67%+/-7%), newborn (82%+/-5%), and adult (97%+/-2%) in an age-dependent manner. The M3 antagonist exhibited robust inhibition at all age groups while the M2 antagonist demonstrated enhanced inhibition in the fetus. Immunohistochemical analysis indicated coexpression of subtype receptors in fetal, newborn, and adult ileal smooth muscle with increasing expression with advancing age. CONCLUSION: These results demonstrate a specific developmental pattern of muscarinic receptor subtype expression. Knowledge and/or alterations of GI motility regulation may aid in the treatment of the preterm fetus or newborn.  相似文献   
60.
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