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101.
The purpose of the study reported here was the determination of the efficacy of a postoperative autologous blood drainage and transfusion device in reducing allogeneic red cell requirements in patients undergoing elective knee arthroplasty. The study was a randomized controlled trial with adult patients undergoing unilateral elective arthroplastic knee surgery. Patients underwent suction drainage, attached to an autologous blood drainage and transfusion device, or standard suction drainage. Allogeneic red cells were given according to strict transfusion guidelines based on blood loss and postoperative hemoglobin values. Outcome measures included the mean number of allogeneic red cell concentrates required and the number of patients in each group who required no transfusion. Patients assigned to standard suction drainage had a mean allogeneic red cell utilization of 1.2 units (SD 1.0), as compared to a mean of 0.4 units (SD 0.8) in the group undergoing drainage with the autologous blood drainage and transfusion device (p = 0.0007). The percentage of patients not requiring allogeneic red cells was significantly higher in the latter group (74.3% vs. 32.5%; p = 0.002). The postoperative drainage and transfusion device was efficacious in reducing the amount of allogeneic red cells required by patients undergoing knee arthroplasty, and its use resulted in a 42 percent reduction in the number of patients requiring allogeneic transfusion.  相似文献   
102.

Background

Preterm labour is the main cause of perinatal morbidity and mortality in the Western world. At present, there is evidence that tocolysis for 48 hours is useful in women with threatened preterm labour at least before 32 weeks. This allows transfer of the patient to a perinatal centre, and maximizes the effect of corticosteroids for improved neonatal survival. It is questionable whether treatment with tocolytics should be maintained after 48 hours.

Methods/Design

The APOSTEL II trial is a multicentre placebo-controlled study. Pregnant women admitted for threatened preterm labour who have been treated with 48 hours corticosteroids and tocolysis will be eligible to participate in the trial between 26+0 and 32+2 weeks gestational age. They will be randomly allocated to nifedipine (intervention) or placebo (control) for twelve days or until delivery, whatever comes first. Primary outcome is a composite of perinatal death, and severe neonatal morbidity up to evaluation at 6 months after birth. Secondary outcomes are gestational age at delivery, number of days in neonatal intensive care and total days of the first 6 months out of hospital. In addition a cost-effectiveness analysis will be performed. Analysis will be by intention to treat. The power calculation is based on an expected 11% difference in adverse neonatal outcome. This implies that 406 women have to be randomised (two sided test, β 0.2 at alpha 0.05).

Discussion

This trial will provide evidence as to whether maintenance tocolysis reduces severe perinatal morbidity and mortality in women with threatened preterm labour before 32 weeks.

Trial Registration

Clinical trial registration: http://www.trialregister.nl, NTR 1336, date of registration: June 3rd 2008.  相似文献   
103.
We consecutively recruited 75 patients with intractable headache syndromes, divided them into three groups (frequent migraine = FM, transformed migraine = TM, and tension type headache = TT) based on their headache symptoms and treated all 75 with divalproex sodium. Thirty-six patients (48%) reported a ³ 50% reduction in headache frequency. We noted significantly different treatment response rates in the three patient groups, with FM patients reporting the highest rate of improvement (11/18 = 61%), TM patients an intermediate rate (22/43 = 51%), and TT patients the lowest response rate (3/14 = 21%), These data suggest that prophylactic therapy with divalproex may be effective in selected patients with intractable headache syndromes and that identification of clinically distinct headache subtypes may assist in predicting response to treatment.  相似文献   
104.
It is generally assumed that febrile nonhemolytic transfusion reactions are an immunologically mediated reaction involving the recipient's plasma and the white cells in the donor unit. This has led to the use of white cell reduction and pretransfusion medication, to try to minimize these reactions. To better understand febrile transfusion reactions, a prospective study was performed in which all patients receiving platelet and red cell transfusions in a tertiary-care medical center were interviewed before and after transfusion to obtain information about the typical presentation of the syndrome. It was found that transfusion reactions were much more frequently associated with platelet transfusion (30.8%) than with red cell transfusion (6.8%, p < 0.0005). The routine use of antipyretics prevented most episodes of fever but did not prevent the occurrence of other symptoms such as chills, cold, and discomfort. The application of logistic regression analysis revealed that the dominant factor determining the risk of a reaction was not white cell contamination, but the age of the component (p < 0.005). The significant relationship between reaction and the increasing age of the component suggests that cytokines released in the component during storage may be responsible for many reactions to blood components.  相似文献   
105.
To evaluate the effectiveness of oral sucrose in the prevention of pain-induced crying in preterm infants, a sample of 28 healthy neonates (15M, 13F; gestational age at procedure less than 37 weeks) who were having routine blood drawn by arm venipuncture was studied. Infants were randomly allocated to receive by mouth, using a syringe, 2 ml of one of three solutions: spring water (group W) and sucrose 12 and 24% w/v (groups S12 and S24, respectively), all in water vehicle. After 2 min, while awake, arm venipuncture was performed and duration of crying was measured. The time spent crying was reduced in the group treated with the sweetest solution (S24, n = 8, mean =19.1 s). No difference was observed between the S12 group ( n = 8, mean = 63.1 s) and W group ( n = 12, mean = 72.9 s). Physiological measurements were recorded at different time points to evaluate excessive basal and procedural distress.  相似文献   
106.
107.
Theoretical analysis predicts that performing magnetic resonance (MR) imaging with partial (less than 90 degrees) flip angles can reduce imaging times two- to fourfold when lesions with elevated T1 values are being examined. This time savings occurs because repetition time (TR) is reduced when imaging is performed with partial flips. Partial flip MR imaging can also improve signal-to-noise ratio (S/N) in fast body imaging. For this study, analytical tools were used to predict image contrast and S/N for short TR, partial flip sequences. Experimental implementation of the short TR, partial flip sequences that analytical work had predicted would be optimal supported the analytical predictions and demonstrated their validity. Partial flip MR imaging is applicable to reducing imaging time only when the ratio of signal differences to noise exceeds threshold values in conventional MR images. Partial flip sequences can be used to advantage in MR imaging of both the head and the body, and the observed effects are predictable through theoretical analysis.  相似文献   
108.
Technetium-99m pyridoxylideneglutamate (P.G.) cholescintigraphy   总被引:1,自引:0,他引:1  
  相似文献   
109.
To date, at least four genes involved in DNA mismatch repair, hMSH2, hMLH1, hPMS1 and hPMS2, have been demonstrated to be altered in the germline of patients with hereditary nonpolyposis colorectal cancer (HNPCC). Additionally, defective mismatch repair is thought to account for the observation of microsatellite instability (MIN) in tumors from these patients. The genetic defect responsible for the MIN+ phenotype in sporadic colorectal cancer, however, has yet to be clearly delineated. In order to better understand the role of somatic and germline alterations within hMSH2 and hMLH1 in the process of colorectal tumorigenesis, we examined the entire coding regions of both of these genes in seven patients with MIN+ sporadic colorectal cancer, 19 patients with familial colorectal cancer, and 20 patients meeting the strict Amsterdam criteria for HNPCC. Thirteen germline, two somatic, and four neutral alterations were identified. The two somatic mutations occurred in patients having familial cancer, while the germline mutations were distributed among one sporadic (14%), three familial (16%), and nine HNPCC (45%) cases. All patients with identified mutations in the mismatch repair genes, whose tumors were available for analysis, demonstrated MIN. On the other hand, we could not identify mutations in the subset of clinically defined HNPCC patients with MIN negative tumors nor in the majority (6/7) of MIN+ sporadic tumors.   相似文献   
110.
The aim of this study was to validate in vivo the accuracy of a reconstruction-based partial volume correction (PVC), which takes into account the point spread function of the imaging system. The NEMA NU2 Image Quality phantom and five healthy volunteers (using [11C]flumazenil) were scanned on both HR+ and high-resolution research tomograph (HRRT) scanners. HR+ data were reconstructed using normalization and attenuation-weighted ordered subsets expectation maximization (NAW-OSEM) and a PVC algorithm (PVC-NAW-OSEM). HRRT data were reconstructed using 3D ordinary Poisson OSEM (OP-OSEM) and a PVC algorithm (PVC-OP-OSEM). For clinical studies, parametric volume of distribution (VT) images were generated. For phantom data, good recovery was found for both OP-OSEM (0.84 to 0.97) and PVC-OP-OSEM (0.91 to 0.98) HRRT reconstructions. In addition, for the HR+, good recovery was found for PVC-NAW-OSEM (0.84 to 0.94), corresponding well with OP-OSEM. Finally, for clinical data, good correspondence was found between PVC-NAW-OSEM and OP-OSEM-derived VT values (slope: 1.02±0.08). This study showed that HR+ image resolution using PVC-NAW-OSEM was comparable to that of the HRRT scanner. As the HRRT has a higher intrinsic resolution, this agreement validates reconstruction-based PVC as a means of improving the spatial resolution of the HR+ scanner and thereby improving the quantitative accuracy of positron emission tomography.  相似文献   
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