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81.
C. J. Bowden W. D. Figg N. A. Dawson O. Sartor R. J. Bitton M. S. Weinberger Donna Headlee Eddie Reed C. E. Myers M. R. Cooper 《Cancer chemotherapy and pharmacology》1996,39(1-2):1-8
Introduction: Suramin is a synthetic polysulfonated naphthylurea which has been used for the treatment of African trypanosomiasis and onchocerciasis,
but since the mid-1980s has received attention as a possible antiretroviral and antineoplastic agent. Objective: This clinical trial of suramin was undertaken as a phase I/II study in patients with hormone-refractory prostate cancer,
with the hypothesis that the intensity of therapy with suramin could be increased significantly if measures were undertaken
to maintain the plasma concentrations of the drug under 300 μg/ml. Methods: We report the clinical results of this trial, wherein patients were treated at three different targeted plasma suramin concentrations
(275, 215 and 175 μg/ml) for varying periods of time (2, 4 or 8 weeks), with delivery of the drug by continuous intravenous
infusion. Results: The major toxicity observed in this trial was neurologic, consisting of a motor and sensory peripheral neuropathy that resulted
in both paresis and paralysis of the limbs. Nearly all of this severe (CTEP grade III, IV) neurologic toxicity was observed
in the patients treated at a plasma suramin concentration of 275 μg/ml for 4 or more weeks. A single patient treated at 215 μg/ml
for 8 weeks developed moderate (CTEP grade III) proximal lower extremity weakness, and no patient treated at 175 μg/ml developed
this toxicity. The second most common toxicity observed was infection of the central venous catheter. The overall response
rate for all of the evaluable patients was 17% (13 of 75 patients). In addition, prostate-specific antigen (PSA)-defined responses
were observed in six patients receiving therapy at 175 μg/ml, but these responses were confounded by cessation of therapy
with flutamide during suramin treatment. Conclusions: In summary, although plasma suramin concentrations were maintained below 300 μg/ml, neurologic toxicity nonetheless occurred
with high frequency in patients treated at 275 μg/ml for 4 or more weeks. Therapy at 215 and 175 μg/ml was in general well
tolerated, but central venous catheter-related infection, as well as the inconvenience and expense of continuous infusional
therapy, make this method of drug delivery impractical. Only moderate antitumor activity was observed during this trial, but
it is possible that both continuation of flutamide and flutamide withdrawal during suramin therapy confounded the assessment
of suramin’s activity in hormone-refractory prostate cancer.
Received: 9 June 1995/Accepted: 18 March 1996 相似文献
82.
D. Novitzky J. Rhodin D.K.C. Cooper Y. Ye K.-W. Min L. DeBault 《Transplant international》1997,10(1):24-32
Abstract Electromicroscopic examinations were carried out on 30 myocardial biopsies taken from 22 human donor hearts immediately after excision (prestorage) or immediately before transplantation (post-storage). All electron micrographs were independently examined by two morphologists. Eleven structures were examined in each micrograph, and each structure was scored according to the degree of injury. A good interobserver correlation was obtained in 84 % of the structures scored. In the prestorage left ventricular biopsies ( n = 11), approximately 20 %-25 % showed moderate to severe ultrastructural injury. The ultrastructural injury observed in the poststorage left ventricular biopsies ( n = 15) was no different from that in the prestorage group, particularly injury to the sarcomere and mitochondria. A similar degree and pattern of injury was seen in the right ventricle ( n = 4). There was no evidence that an ischemic storage period of less than 6 h increased the degree of injury seen. However, there was a higher incidence of moderate to severe injury in those hearts excised from donors initially dependent on high inotropic support. 相似文献
83.
Amy J Bastian Valerie E Kelly Fredy J Revilla Joel S Perlmutter Jonathan W Mink 《Movement disorders》2003,18(9):1000-1007
The purpose of this study was to determine the effects of unilateral versus bilateral subthalamic nucleus (STN) stimulation on quantitative measures of walking and reaching in Parkinson's disease (PD). We used kinematic measures and the Unified Parkinson's Disease Rating Scale (UPDRS) motor subscale (subscale III) to evaluate the movement of 6 people with PD who had bilateral STN stimulators implanted for at least 6 months and withheld their anti-parkinson medication for at least 8 hours. Subjects were studied with both stimulators off, one on, and both on. Kinematic data were collected as subjects walked, reached to a target, and were rated using the UPDRS motor subscale. STN stimulation improved walking speed and stride length, with the greatest benefit from bilateral stimulation. Reaching speed was improved by unilateral STN stimulation alone, with no additive effect of bilateral stimulation. UPDRS motor subscale ratings paralleled the kinematic findings. STN stimulation did not restore PD subjects' movements to the level of age-matched controls. Overall, these results provide further evidence that the basal ganglia pathways involved in control of walking and reaching may be distinct. We speculate that basal ganglia may influence walking through bilateral pedunculopontine projections and reaching through ipsilateral thalamocortical projections. Our findings also suggest that maximal improvement of walking requires bilateral rather than unilateral STN stimulation. 相似文献
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A stratified sample of normal infants born at term at Johannesburg Hospital, who attended the hospital for a routine 6-week follow-up visit, were selected to include 43 infants who were exclusively breast-fed, 42 fed a low-sodium formula and 39 fed a high-sodium formula (greater than 10 mmol sodium/l). Dynamic skinfold thickness measurements (DSTM), designed to assess the amount of interstitial fluid, were performed on each infant by the application of a skinfold caliper for a 3-second sampling period at two sites. The curves generated by these applications were recorded and analysed by microcomputer. There were no differences between any of the feeding groups for DSTM measurements of blood pressure suggesting that the range of sodium ingested by these groups of infants had no significant effects on extracellular water content. However, using multiple linear regression, both DSTM and blood pressure were best predicted by body weight and not by age or any other anthropometric measurement. Thus the normal postnatal decrease in extracellular fluid volume and increase in blood pressure appears to be most closely related to an increase in body weight. 相似文献
87.
Richard J Levy Whitney B Stern Kimberly I Minger Lisa M Montenegro Chitra Ravishankar Jonathan J Rome Susan C Nicolson David R Jobes 《Pediatric critical care medicine》2005,6(6):671-675
BACKGROUND: Mixed venous saturation (S & OV0456;o2) is an important measurement that helps guide the care of critically ill patients. Invasive S & OV0456;o2 assessment in infants and children is often avoided because of the inherent risks. A noninvasive tissue saturation (S to 2) monitor has recently been developed that uses near-infrared spectroscopy to measure oxyhemoglobin saturation in muscle. In adult and animal studies, S to 2 correlated with oxygen delivery and S & OV0456;o2. There has been no evaluation in pediatric patients. OBJECTIVE: To evaluate tissue saturation as a noninvasive measure of mixed venous saturation in children. DESIGN: A prospective observational study. SETTING: Catheterization laboratory in a tertiary care children's medical center. PATIENTS: We studied 98 children (49 without intracardiac mixing and 49 with intracardiac mixing) 相似文献
88.
Hao Wu Colin Webber Carmen Otero Fuentes Robert Bensen Karen Beattie Jonathan D Adachi Xiaoming Xie Farhang Jabbari David R Levy 《Journal l'Association canadienne des radiologistes》2007,58(3):167-175
OBJECTIVES: 1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups. METHODS: Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion. RESULTS: Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects. CONCLUSION: The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities. 相似文献
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