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11.
Amifostine (AMF) promotes in vitro growth and survival of hematopoietic progenitors. In this study we evaluated the efficacy of AMF in the treatment of anemia in patients with low-risk myelodysplastic syndromes (MDS) and the possible predicting value for response to AMF therapy of two types of in vitro clonogenic assays. Two different doses of AMF, 300 mg/m2 (group A, 11 patients) or 400 mg/m2 (group B, 16 patients), were studied. AMF was given three times weekly for 3 weeks, i.v., followed by 2 weeks off therapy. Patients were evaluated after two cycles of treatment. Partially or nonresponding patients of group A received 400 mg/m2 AMF and were reevaluated. An increase of hemoglobin (Hb) values of more than 2 g/dl and a 100% decrease in transfusion requirements for at least 6 weeks were defined as a complete response (CR) while an increase of Hb values of 1-2 g/dl or a 50% decrease in transfusion requirements was considered as a partial response (PR). In group A, two out of 11 (18.1%) patients achieved a CR with the initial dose and one of the nine that received 400 mg/m2 AMF achieved a PR. In group B, three out of 16 (18.7%) patients achieved a PR; the overall response rate in both groups was 22.2%. In group A, bone marrow progenitor assay was performed pre- and post-amifostine treatment. Erythroid burst-forming units (BFU-E) were increased in six out of 11 (54.5%) patients, and this increase preceded the rise in Hb levels in three of them. In group B, a clonogenic assay was performed in 11 out of 16 patients before AMF treatment. In vitro results after pretreatment with 500 microM amifostine confirmed the response of two MDS patients that achieved a PR. No response in vitro was observed in all eight nonresponding patients and in one PR patient. The lack of response in the clonogenic assays predicted for nonresponse to treatment with a predictive power of 91.8%. We conclude that 300 mg/m2 is an adequate initial treatment for low-risk MDS patients and both clonogenic assays have a strong predicting value for response to treatment.  相似文献   
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This paper reports two cases of acrometastasis to the hands. The first case involved a 78-year-old woman with a permeative osteolytic lesion in her proximal second metacarpal. A biopsy of this lesion suggested a diagnosis of non-small-cell lung carcinoma with secondary osseous metastasis. This was the first presentation of the woman’s primary diagnosis. A single 8-Gy fraction of palliative radiotherapy was delivered to the patient’s left hand. The treatment proved successful: the woman soon experienced pain relief and regained the use of her hand. The second case involved a 69-year-old woman with extensive lytic destruction involving the proximal two thirds of her third metacarpal. This patient had been diagnosed with carcinoma of the breast in 1990. She also received a single 8-Gy fraction of radiation, which improved both her pain and her hand mobility.An extensive review of the literature uncovered 257 previously reported cases of acrometastasis. Articles were analyzed based on age and sex of the patient, site of the primary carcinoma, metastatic locations within the hand and affected appendage or appendages, the treatment given, and the patient’s length of survival. Men were almost twice as likely to experience acrometastasis as women, and the median age of the patients overall was 58 years (range: 18 months–91 years). Lung, kidney, and breast carcinoma were the three most prevalent primary diagnoses reported in the literature. Cancers of the colon, stomach, liver, prostate, and rectum affected the remainder of the population.Overall, the right hand was more often host to the metastatic lesions. In addition, almost 10% of the patients experienced lesions in both hands. The third finger was the digit most affected by osseous metastases reported in the literature. Lesions of the thumb, fourth finger, second finger, and fifth finger were less commonly reported. The region of the digit most often affected within the patient population was the distal phalanx. The metacarpal bones, proximal phalanges, and middle phalanges comprised the remainder of the four most frequent acrometastatic sites. In the literature, single lesions were more prevalent than multiple bony lesions.Based on the reported cases, amputation appeared to be the preferred method of treatment. Radiation, excision, and systemic therapy were the next most frequently used treatments. Patient survival was not well documented within the literature. However, the median survival of patients in the reported cases was 6 months. Thus, our review suggested that a diagnosis of hand metastasis is an indication of poor prognosis.This report serves to emphasize the importance of properly diagnosing acrometastases. Identifying and effectively treating these metastases in a timely manner can lead to a dramatic improvement in a patient’s quality of life.  相似文献   
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OBJECTIVES: This study assessed whether greater continuity of care is associated with timely administration of measles-mumps-rubella (MMR) vaccination. METHODS: We studied 11,233 patients continuously enrolled in Group Health Cooperative (GHC) from birth to 15 months. We used a preestablished index to quantify continuity of care based on the number of primary care providers in relation to the number of clinic visits. MMR vaccination status at 15 months was assessed with automated immunization data systems at GHC. RESULTS: In a logistic regression model, both medium continuity (odds ratio [OR] = 1.20, 95% confidence interval [CI] = 1.08, 1.33) and high continuity (OR = 1.36, 95% CI = 1.22, 1.52) were associated with increased likelihood of being immunized by 15 months compared with patients in the lowest tercile of continuity of care. CONCLUSION: Greater continuity of care is associated with more timely immunization.  相似文献   
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BACKGROUND: Although stentless aortic bioprostheses are believed to offer improved outcomes, hemodynamic benefits remain unsubstantiated. METHODS: Fifty-three patients were randomized to receive the stented C-E pericardial valve (CE) and 46 patients the Toronto Stentless Porcine valve (SPV). Annuli were sized for the optimal insertion of both valve types, such that surgeons were required to commit to specific valve sizes before randomization. Echocardiographic measurements and functional status (Duke Activity Status Index) were assessed at 3 and 12 months postoperatively. RESULTS: Although cardiopulmonary bypass times (CE: 118.6+/-36.3 minutes; SPV: 148.5+/-30.9 minutes; p = 0.0001) and aortic cross-clamp times (CE: 95.4+/-28.6 minutes; SPV: 123.6+/-24.1 minutes; p = 0.0001) were significantly prolonged in the SPV group, perioperative morbidity and mortality was similar between groups. Neither valve offered a superior internal diameter for any given annular diameter (mean decrease in left ventricular outflow tract diameter after valvular implantation: SPV: 3.4+/-1.11 mm versus CE: 3.7+/-1.33 mm; p = 0.25). Although labeled mean valve size was significantly larger in the SPV group, the actual mean valve size based on internal valvular diameter was no different between groups (CE: 21.9+/-2.0 mm; SPV: 22.3+/-2.0 mm; p = 0.286). Although effective orifice areas increased, and mean and peak transvalvular gradients decreased in both groups over time, no differences were demonstrated between groups at 12 months. Similarly, although significant regression of left ventricular mass was accomplished in both groups over time, no differences were demonstrated between groups. Finally, Duke Activity Status Index scores of functional status improved in both groups over time; however, no differences were noted between groups at 12 months postoperatively. CONCLUSIONS: Although offering excellent outcomes, stentless valves did not demonstrate superior hemodynamic indices in comparison to stented valves up to 12 months after implantation.  相似文献   
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Summary. Four stable and 12 unstable trochanteric fractures were produced in human cadavers and fixed with either a sliding screw-plate or the Bousquet nail-plate. Axial cyclic loading showed that both implants were satisfactory for stable fractures. The sliding screw-plate withstood increased loads and the system failed at a later cycle in unstable fractures. Central placement of both the sliding screw or nail enhances stability, especially against torsional forces.
Résumé. Quatre fractures stables et douze fractures instables ont été expérimentalement produites sur des fémurs de cadavres. Une fixation interne a suivi au moyen d’une vis-plaque glissante et d’un clou-plaque Bousquet. Par l’usage d’une charge axiale, cyclique il a été démontré que les fractures stables ont étéégalement bien traitées par les deux méthodes. Dans le cas des fractures instables, la vis-plaque glissante a résistéà de plus grandes charges par rapport au clou-plaque Bousquet et le système a défailli plus tard. Le placement central de la vis glissante et du clou, ameliore biomécaniquement la stabilitè et spécialement la résistance contre les forces de rotation.


Accepted: 25 Mai 1995  相似文献   
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BACKGROUND: The prevalence of childhood overweight and obesity has been increasing rapidly during the past decades in many parts of the world. Less is known with respect to the effects of increasing adiposity on blood lipid profile. The present study was designed to examine the influence of adiposity on secular trends in anthropometric characteristics and plasma lipids of Greek children. METHODS: A total of 419 and 374 boys with normal body weight and 109 and 246 boys with abnormal body weight (overweight and obese) were randomly recruited in 1982 and 2002, respectively (aged 12.1 +/- 0.1 years). Height, weight, body mass index (BMI, kg/m(2)), Rohrer index (kg/m(3)), plasma total cholesterol (TC), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C), triglyceride (TG), TC/HDL-C ratio, and LDL-C/HDL-C ratio were determined. RESULTS: Temporal changes in weight (positive), BMI (positive), HDL-C (negative), and cholesterol ratios (positive) were greater among overweight and obese vs. normal-weight boys (P < 0.05), while those for height (positive), LDL-C (positive), TG (positive), and TC (no change) were of similar magnitude. The increase in Rohrer index since 1982 failed to reach significance for children with normal body weight (P = 0.077) but did so for overweight and obese subjects (P = 0.027). CONCLUSIONS: These results indicate that secular increases in measures of fatness and adverse changes in plasma lipids were more pronounced among overweight and obese children than among normal-weight individuals, although qualitatively similar shifts were observed across the entire population.  相似文献   
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OBJECTIVE: To determine pediatricians' routine screening urinalysis practices. STUDY DESIGN: This was a survey of a nationally representative sample of pediatricians practicing in the U.S. regarding their screening urinalysis practices in childhood. RESULTS: Of the 1502 pediatricians sampled, 653 eligible subjects participated, for an estimated response rate of 49.5%. The vast majority of participants (78%) routinely screen asymptomatic children with urinalysis in at least 1 age group. Pediatricians' screening urinalysis practice varies based on age group: 9% screen during infancy (<1 year), 60% screen during early childhood (1 up to 5 years), 55% screen during late childhood (5 to 12 years), and 58% screen during adolescence (13 to 20 years). The majority of pediatricians (58%) routinely screen more than 1 age group. Some 38% of the pediatricians surveyed believe that the overall health of children is improved by screening all asymptomatic children with urinalysis. CONCLUSIONS: Many pediatricians routinely conduct screening urinalysis during childhood, frequently at ages not recommended by the American Academy of Pediatrics.  相似文献   
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