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51.
Transformed fibroblasts have been recently shown to be sensitive for induction of apoptosis by TGF-beta-treated neighbouring untransformed cells. Cells transformed by a variety of different transformation principles were regularly sensitive for intercellular induction of apoptosis, but fibroblasts transformed by bovine papillomavirus (BPV) represented a striking exception. In contrast to chemically transformed C127 cells, BPV-transformed C127 cells showed resistance against intercellular induction of apoptosis. In addition, BPV-transformed cells were resistant against induction of apoptosis by ROS in glutathione depleted cells. The antiapoptotic function of papillomaviruses may be of central importance for papillomavirus-induced tumor formation as it can protect transformed cells from intercellular control of oncogenesis.  相似文献   
52.
This paper analyzes the effect of quality and accessibility of health services and other public infrastructure on the health of children in Ghana. We focus on child survival, child height and weight using data from the Ghana Living Standards Survey. The results suggest an important role for public health policy in eliminating the rural-urban disparities in health status and particularly in improving the health status of rural children and reducing their mortality rates. Increased availability of birth services and other related child programs, as well as Improved water and sanitation infrastructure would have an immediate payoff.  相似文献   
53.
54.
99mTc-labeled nucleotides as tumor-seeking radiodiagnostic agents.   总被引:1,自引:1,他引:0       下载免费PDF全文
Several lines of human tumor cells in monolayer and soft agar cultures allow permeation of low levels of adenine nucleotides through their plasma membranes, while, in general, untransformed cells do not incorporate adenine nucleotides into their cellular pools without prior degradation of the nucleotides to adenosine. This study determined the uptake of 99mTc-radiolabeled chelated forms of adenine nucleotides, 99mTc-Ap4A (diadenosine 5',5"',P1,P4-tetraphosphate) and 99mTc-ATP chelates as radiodiagnostic agents suitable for the in vivo detection of tumors by radionuclide imaging. Biodistribution studies revealed that Ap4A accumulated preferentially in RT-24 tumors implanted in rats and that V2 carcinoma implanted in rabbits could be readily visualized by in vivo imaging. The biodistribution at various time points showed increased tumor-to-muscle ratios after 99mTc-Ap4A or 99mTc-ATP injections when compared with a nonspecific marker of the extracellular fluid space, 99mTc-labeled diethylenetriaminepentaacetic acid and with an agent known to localize in some tumors, 67Ga-labeled citrate. Studies of ectoenzymatic activities of virus-transformed animal cells and their untransformed counterparts in monolayer cultures showed marked decreases in the ectoenzymatic activities that degrade Ap4A in the transformed cells. Incorporation of en bloc [3H, 32P]Ap4A into cellular acid-soluble nucleotide pools of certain transformed cells was observed. Normal untransformed cells incorporated the radioactive label only by prior degradation to [3H]adenosine and 32Pi.  相似文献   
55.
Hemodynamic assessment of aorto-iliac occlusive disease is necessary for successful arterial reconstruction of the legs. Various methods have been proposed and the "pull-through" intra-arterial pressure measurement method is accepted as the best standard. The pressure readings, however, seemed to depend on the intraluminal position of the catheter. To explain these observations and make a comparison between the Doppler method and the "pull-through" method, we have studied center-line velocity changes at the stenosis throat by Doppler ultrasound, and axial and lateral pressure gradients using pressure transducers, mounted 10 mm and 40 mm downstream of short (4 mm) and long (40 mm) axisymmetric sharp-edged model stenoses having cross sectional reduced areas of 64%, 84%, 91%, and 96%. Axial manometric pressures measured 10 mm after the throat of 84% stenosis were more than twice as high as the lateral pressures. There was no significant difference between axial and lateral pressures measured 40 mm downstream from throat. This pressure distribution has important clinical relevance. Mean and peak pressure gradients for both the Doppler method and manometric measurements were compared. Measurements with Doppler method and manometric measurements, indicated that mean pressure gradients (r = 0.98; SEE = +/- -2.4 mmHg) correlate better than peak pressure gradients (r = 0.90; SEE = +/- 16.5 mmHg). Doppler gradients were higher than manometer gradients. Overestimation was 13% for mean pressure gradients, and ranging from 10% to 150% for peak pressure gradients. Explanation for the difference between mean Doppler and catheter gradient may be the pressure recovery occurring in the relaminarized poststenotic regions.  相似文献   
56.
Awareness of illness in schizophrenia   总被引:6,自引:0,他引:6  
This article reviews the literature on "poor insight" or unawareness of illness in schizophrenia. A large body of knowledge representing several different perspectives on insight has developed. This work can be divided into three broad categories, suggesting an important role for insight in the phenomenology, pathophysiology, and treatment of schizophrenia. The argument is made here that many of the self-awareness deficits observed in schizophrenia are of diagnostic significance, are neurally based, and are indispensable in guiding treatment decisions. In addition, this article proposes guidelines for assessing unawareness of illness in schizophrenia and discusses the relevance of such deficits to the diagnosis of schizophrenia.  相似文献   
57.
A skeletal seeking radiopharmaceutical labeled with a long-lived radionuclide was developed to evaluate regional bone formation and its subsequent resorption. The agent is [phosphonate (phenylmethylene hydroxy) bis]-I-125 or I-125 PA. Tissue distribution studies in mice (N=16) showed approximately 40% of the administered dose to be retained by the skeleton up to 336 hours post IV injection. The percentage of the dose accumulated by the thyroid gland remained at less than 0.5%, indicating minimal deiodination of the I-125 PA. Whole body retention studies in the same species revealed a triexponential release pattern with the longest component comprising 33% of the dose with a biologic half-life of 962 days. A fractured rat tibia model was studied with I-125 PA and Tc-99m MDP. Chronic loss of the I-125 PA relative to normal tibia was quantitated: five days (62.8%); 30 days (47.4%). Concomitant increased uptake of the Tc-99m MDP was observed at the fracture site relative to normal: five days (186%); 30 days (1,041%). The above data suggest that I-125 PA can be utilized to measure acute bone formation and chronic resorption.  相似文献   
58.
The Raji human lymphoma line is able to remove O6-methylguanine(O6MeG) lesions introduced by treatment of cells with N-methyl-N'-nitro-N-nitroso-guanidine(MNNG). The reaction has a rapid phase in which 40% of theO6MeG is removed in the first 10 min. The capacity of cellsfor rapid O6MeG removal is limited and is saturated at concentrationsof MNNG which do not saturate the systems removing 3-methyladenine.Pretreatment of cells with MNNG inhibits their ability to removeO6MeG produced by a subsequent dose given after 2 h. Treatmentwith N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) is effectivein diminishing cellular capacity for O6MeG removal, and cellsunable to remove O6MeG and sensitive to the cytotoxic effectsof MNNG are also more sensitive to ENNG than their removal competentcounterparts. Regeneration of the ability to remove O6MeG requiresincubation of cells for periods > 24 h. The O6MeG removalsystem is similar to that found in adapted Escherichia colialthough the capacity of the Raji lymphoma line is much lowerthan that of the induced bacteria per unit of DNA.  相似文献   
59.
The goals of the study were to determine how neuropsychological functioning is related to depressive status in persons with head injury, and to quantify this relationship from a clinically relevant standpoint. Participants were 175 adults involved in litigation, referred for evaluation of suspected head injury. Depression status was measured using the Depression Content (Dep) scale of the MMPI-2. Depression status was related to measures of visual attention and psychomotor skills, but not to other neuropsychological domains such as verbal ability, visual-spatial reasoning, or encoding/organization. However, differences between low Dep and high Dep groups were minimal from a clinical standpoint. Depression appeared to contribute to an increased risk of impaired neuropsychological performance across domains, but only in persons not severely compromised by neuropsychological deficits. Overall, the results indicated a small effect of depression on neuropsychological functioning that is likely only detectable in persons whose neuropsychological compromise is relatively minimal.  相似文献   
60.
Objectives. To evaluate the cost effectiveness of transurethral microwave thermotherapy relative to medical therapy (alpha-blocking agents) and transurethral resection of the prostate (TURP) for patients with moderate-to-severe benign prostatic hyperplasia (BPH) symptoms.Methods. A cost-effectiveness analysis was performed from the societal perspective for a hypothetical cohort of 65-year-old men with moderate-to-severe BPH symptoms. We calculated the incremental cost effectiveness of thermotherapy relative to medical therapy and TURP during 5 years after treatment initiation. Event probabilities were obtained from published reports, a consensus panel, and the Targis System (Urologix) randomized clinical trial. Costs were estimated using the national Medicare reimbursement schedules. Costs are reported in 1999 U.S. dollars. Total thermotherapy procedure costs were estimated at $2629. Quality-of-life and utility estimates were obtained by interviewing 13 patients with moderate-to-severe BPH symptoms. On the basis of their risk attitudes, patients were classified into risk-averse or non-risk-averse groups. The costs and health effects were discounted at 3% annually.Results. In a hypothetical cohort of 10,000 non-risk-averse patients who were candidates for all three modalities, the 5-year costs were highest for patients undergoing TURP and lowest for those receiving medical therapy ($7334 and $6294, respectively). The thermotherapy group exhibited the highest 5-year utility value (53.52 quality-adjusted life-months). Compared with medical therapy, thermotherapy resulted in an additional 0.23 quality-adjusted life-months, with an incremental cost of $741. This yielded an incremental cost per quality-adjusted life-year gained of $38,664 for thermotherapy compared with medical therapy. Thermotherapy had a higher utility (difference of 1.71 quality-adjusted life-months) and lower cost (difference of $299) compared with TURP and thus was dominant over TURP. The results were similar for a hypothetical cohort of 10,000 risk-averse patients.Conclusions. From a societal perspective, thermotherapy appears to be a reasonable and cost-effective alternative to both medical and surgical treatment. However, the actual treatment decision should be based on multiple factors, only one of which is cost effectiveness.  相似文献   
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