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Retinopathy is an important sequela of diabetes mellitus, but clinical risk factors for this condition have rarely been assessed in a geographically defined population. In this population-based study, the 1135 Rochester, Minnesota, residents with diabetes mellitus initially diagnosed between 1945 and 1969 (incidence cohort) were followed through their complete medical records in the community to January 1, 1982. Because most of the cases of diabetic retinopathy in Rochester residents developed in patients with non-insulin-dependent diabetes mellitus (NIDDM), risk factors for diabetic retinopathy were examined in this group (N = 1031). A proportional hazards model identified the following risk factors for diabetic retinopathy in NIDDM: elevated initial fasting blood glucose level, marked obesity, and earlier age at onset of diabetes. Stratified analyses indicated that duration of diabetes was also significantly associated with an increased risk of retinopathy. Two secular trends, increasing detection of "mild" NIDDM and decreasing risk of diabetic retinopathy, had a major effect on retinopathy risk assessment. These data also suggest that insulin therapy is not an independent risk factor for diabetic retinopathy.  相似文献   
23.
The use of apheretic procedures in pediatric patients has always been restricted by technical difficulties and the low incidence of diseases requiring this kind of treatment. The aim of the present study was to describe the solutions adopted to solve technical difficulties related to priming, vascular access and monitoring and then to evaluate clinical results. Between 1982 and 2000, 51 consecutive children (28 male, 23 female) with a mean age of 4.9 +/- 4.8 years (3 months-14.8 years) and a mean weight of 19.7 +/- 12.8 kg (5-52 kg), with renal and/or extra-renal diseases requiring apheretic procedures were selected for the study. The overall number of procedures performed were: 226 plasma-exchange (PE), 6 LDL-apheresis (LDL-A) and 8 protein A immunoadsorption (IAPA) sessions. Our therapeutic protocol involves hematic flux of 20-100 ml/min and ultrafiltration of 5-20 ml/min. In each 70-95 minute session we exchanged plasmatic volume with fresh frozen plasma or with a solution of 6% albumin in lactated Ringer's, using heparin (10-20 UI/kg/h). We used Paired Filtration Dialysis Monitor in PE and LDL-A; Citem 10 in IAPA. As plasma separator, we used a filter made of polypropylene, 0.2 m2 surface, 30 ml priming (Hemaplex BT 900). Hemolytic uremic syndrome was the most commonly treated disease (18/51 cases) with good results in 10/18 cases. We recorded, good results in vasculitis as well, in one girl with focal glomerulosclerosis in transplanted kidney and rapid improvement in all children with Guillaine-Barré Syndrome. PE treatment was effective in metabolic disorders such as tirosynemia and familiar hypercholesterolemia. Only 4/12 patients with acute liver failure due to viral hepatitis recovered. We had poor results in the remaining eight cases. Complications were rare and no viral infection was found in any patient. Our data show that it is possible to use these procedures in pediatric patients even though clinical indications and real effectiveness still need to be cleared up.  相似文献   
24.
We report 9 cases of aphasia following lesions in the region of the left frontal operculum. It is not possible to capture their variety of clinical manifestations with the simple labels of "Broca's area aphasia." or "Broca's area aphasia." Analysis of the breakdown of various components of speech and language in these cases suggests that the operculum, lower motor cortex, and subjacent subcortical and periventricular white matter contain critical parts of different language systems. These systems can be independently impaired. There are several common language syndromes that follow damage that includes the left frontal operculum. These syndromes reflect the effects of the direction and extent of the lesion in the various language systems.  相似文献   
25.
Fourteen patients with advanced soft tissue sarcomas (STS), all pre-treated with one or more chemotherapy (CT) lines, entered an outpatient phase 11 study in which subcutaneous recombinant Interleukin-2 (rIL-2) and intramuscular recombinant alpha-2a-interferon (r-alphaIFN) were concomitantly administered. Both the cytokines were given for 5 days/week for 3 consecutive weeks followed by a 2 weeks period during which only r-alphaIFN was administered. r-alphaIFN was provided at a dose of 3 x 10(6) International Units (IU), while rIL-2 was given at a dosage of 6 x 10(6)/m2/day IU (in 2 subcutaneous injections), starting from 2 x 10(6)/m2/day IU in the first week and progressively increasing to 4 and 6 x 10(6)/m2/day IU in the second and third weeks; in 4 patients the dose of 8 x 10(6)/m2/day IU was reached. Toxicity was moderate and correlated with rIL-2 dose; main side effects included changes in liver functionality tests (14/14), fever (13/14), fatigue (13/14), nausea and vomiting (9/14). In all 11 patients evaluable for response, stable disease (SD) was observed (duration 4-43 weeks; median 9 weeks); the median survival from the starting treatment was 18 weeks (range 10-52). In all treated patients, an immunological monitoring was performed: an increase in percentage (from 10 to 74%) and in absolute number (from 400 to 4.500 cells/mm3) of CD16+ lymphocytes (NK cells) was observed in the majority of cases. Our data indicate that this regimen can be administered in pre-treated and severely immunocompromised patients with minimal to moderate toxicity on ambulatory and home bases, with acceptable clinical results.  相似文献   
26.
AIM: To measure mucosal concentrations of mesalazine in ulcerative colitis patients treated with oral mesalazine alone, compared to patients treated with both topical and oral mesalazine. METHODS: Twenty-two patients with mild to moderate ulcerative colitis were randomized to receive 2.4 g/day of oral mesalazine (11 patients) or 2.4 g/day oral plus 4 g/day of topical mesalazine (11 patients). After 2 weeks of treatment, endoscopic biopsies specimens were taken from the rectum and in descending colon just distal of the splenic flexure and stored to -80 degrees C for later assay (HPLC). Wilcoxon's rank sum test for unpaired data was used for the statistical analysis. RESULTS: Mucosal levels of mesalazine in the rectum were significantly higher in patients who received oral plus topical treatment than in those who had oral treatment alone (52.1 ng/mg, range: 13.6-122.1 vs. 0.2 ng/mg, range: 0.2-9.7, respectively; P < 0.0001). Similarly, in the descending colon, the mucosal concentrations of mesalazine were significantly higher in patients who had oral plus topical treatment than in those receiving oral treatment alone (46.6 ng/mg, range: 6-112.6 vs. 15.9 ng/mg, range: 2.3-42.4, respectively; P=0.01). CONCLUSIONS: Topical treatment of mesalazine significantly increases mucosal concentrations of mesalazine up to the splenic flexure, supporting the rationale to treat left-sided ulcerative colitis with topical formulations of mesalazine.  相似文献   
27.
Twelve patients with ventricular arrhythmias were given 300-900 mg oral of propafenon daily. We have obtained VT's suppression in 6 of 8 cases (75%) and "complex" VEB's suppression or significant reduction in 6 of 10 cases (60%). Total VEB have been strongly reduced (-91,2%) in 7 of 12 patients (58,3%). The effects of Propafenon on electrocardiographic intervals have not been significant at lower doses and only with 900 mg we have noted a significant (p less than 0,05) lengthening of the P-R (+27,1%) and QTc (+10,2%) intervals. Propafenon has never caused important negative inotropic effects. These results have been confirmed during a follow-up period of 5-19 months. In conclusion we believe that Propafenon must be considered a highly efficient drug for the treatment and prevention of refractory ventricular arrhythmias.  相似文献   
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Background: Ifosfamide has important activity in pretreated soft tissue sarcomas (STS), and recent data support a clinically significant dose-response relationship for this agent. Administration by continuous infusion and hematopoietic support have rendered dose intensification regimens possible by reducing both hematologic and non-hematologic toxicities. The optimal dose and schedule of ifosfamide when given at high doses remain to be defined. In a previous phase I study, we demonstrated the feasibility of a continuous infusion (c.i.) high-dose ifosfamide (HDI) regimen in the ambulatory setting for patients with advanced solid tumors. The objective of the present phase II study was to assess the antitumor activity and toxicity of such a schedule in patients with advanced pretreated STS.Patients and methods: Thirty-eight patients with advanced and/or metastatic STS, all pretreated with an anthracycline with or without standard-dose ifosfamide, were treated. Ifosfamide was given by c.i. at a dose of 3.5 g/m2/day over four consecutive days, with equidose mesna uroprotection over five days. G-CSF was added at a dose of 200 µg/m2/day subcutaneously from day 6 to day 12. Cycles were repeated every three weeks in the outpatient setting.Results: A total of 159 cycles of therapy were given (median 4 per patient, range 3–6). Treatment compliance was generally satisfactory. The major toxicity was hematologic, with six febrile neutropenic episodes requiring hospitalisation and parenteral antibiotics. Acute renal failure occurred in one patient after three cycles of therapy; central nervous system toxicity was mild. An overall response rate of 39% was observed (95% confidence interval, 26% to 55%), with one complete and 14 partial remissions. All but one of the responder patients had previously received standard-dose ifosfamide. The median response duration was nine months (range 5–21+ months), and the overall median survival ranged from 6–30+ months (median 13 months).Conclusions: High-dose ifosfamide is an active regimen in anthracycline- pretreated STS. Future clinical trials should be aimed at evaluating the impact of different administration schedules on clinical response and outcome. The potential role of HDI as front-line chemotherapy as well as in the adjuvant treatment of STS needs to be investigated in randomized trials.  相似文献   
30.
Multiple factors contribute to the development of posttraumatic empyema. These factors include the conditions under which the tube is inserted (emergent or urgent), the mechanism of injury, retained hemothorax, and ventilator care. The incidence of empyema in placebo groups ranges between 0 and 18%. The administration of antibiotics for longer than 24 hours did not seem to significantly reduce this risk compared with a shorter duration, although the numbers in each series were small. Most reports found a significant reduction in pneumonitis when patients received prolonged prophylactic antibiotics. This use of antibiotics might possibly be better described as presumptive therapy rather than prophylactic.  相似文献   
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