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41.
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缺血性卒中或短暂性脑缺血发作患者的卒中预防指南   总被引:8,自引:0,他引:8  
这份新声明旨在为缺血性卒中或短暂性脑缺血发作存活者的缺血性卒中预防提供全面和及时的循证推荐,循证推荐包括对危险因素的控制,动脉粥样硬化性疾病的干预措施,心源性栓塞的抗栓治疗以及非心源性卒中抗血小板药的应用。另外,还为其他多种特殊情况下复发性卒中的预防提供了推荐、包括动脉夹层分离、卵圆孔未闭、高同型半胱氨酸血症、高凝状态、镰状细胞病、脑静脉窦血栓形成、女性卒中(特别是与妊娠和绝经后激素替代治疗相关卒中),脑出血后肮凝药的应用,以及该指南在高危人群中执行和应用的特殊措施。  相似文献   
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A 15 year old girl with a family history of type 1 multiple endocrine adenomatosis presented with reversible neurological disturbances, hypoglycaemia and hyperinsulinaemia. Initial radiology was normal, but portal venous sampling suggested an insulinoma in the tail of the pancreas which was removed with conservation of the spleen. Hypoglycaemia persisted despite high doses of diazoxide and intravenous dextrose. A second laparotomy revealed a pancreatic endocrine tumour and sub-total pancreatectomy was performed. Histology revealed islet cell microadenomatosis. Hypoglycaemia persisted despite treatment with somatostatin analogues and 40% intravenous dextrose was required to maintain normoglycaemia. A possible lesion near the splenic hilum on computed tomographic scan was reported as a splenunculus although further peripheral, hepatic and portal venous sampling suggested hepatic or systemic lesions. A positron emission scan and selective visceral angiography suggested a lesion in the left upper quadrant. Acute lactic acidosis, rhabdomyolysis and renal failure supervened. Post mortem revealed the putative ''splenunculus'' to be a residual insulinoma, whilst the splenic vein was thrombosed, accounting in part for discrepant venous sampling data. Hyperinsulinaemia in type 1 multiple endocrine adenomatosis may require more aggressive surgical and hormonal intervention than when dealing with solitary insulinomas. Insulinomas may mimic developmental abnormalities on computed tomographic scanning.  相似文献   
44.
31P magnetic resonance spectroscopy has been used to compare the effects of the vasoactive agents hydralazine and flunarizine on the oxygenation of the transplantable tumors, SCCVII/Ha and 16C, and a range of spontaneous mammary tumors arising in the breeding stock in the Genetics Division at the Radiobiology Unit. The vasodilator hydralazine, previously shown to increase the radiobiological hypoxic fraction of transplantable murine tumors, increased inorganic phosphate to total phosphate (Pi/total) in SCCVII/Ha and 16C tumors. However, only two spontaneous tumors responded to this agent (2/12). The calcium antagonist flunarizine, which sensitizes the SCCVII tumor to X rays, consistent with a reduction in hypoxic fraction, reduced Pi/total in this and the 16C tumor. Further, most spontaneous tumors tested (8/10) responded to this agent, as measured by a reduction in Pi/total. These results point to fundamental differences between transplantable and spontaneously arising tumors in mice in their response to vasoactive agents.  相似文献   
45.
The sonographic appearances in postpartum thyroiditis.   总被引:2,自引:0,他引:2  
During the postpartum period about 50% of women with circulating thyroid autoantibodies develop a transient autoimmune thyroiditis. To determine the sonographic appearances in postpartum thyroiditis (PPT), serial ultrasound (US) scans of the thyroid were performed in 135 postpartum women who were divided into three clinical groups: Group 1, 37 antibody positive subjects who developed PPT; Group 2, 28 antibody positive subjects in whom thyroid function remained normal; Group 3, 70 antibody negative controls. Thyroid hypoechogenicity was observed in 14/31 patients (45%) who were scanned between 4 and 8 weeks postpartum and who subsequently developed PPT (Group 1) compared with 4/24 patients (17%) in Group 2 (P less than 0.05) and 1/65 patients (1.5%) in Group 3 (P less than 0.001). In antibody positive patients, the positive predictive value of an abnormal scan during this period was 78%. Between 15 and 25 weeks postpartum thyroid hypoechogenicity was present in 32/37 patients (86%) in Group 1 compared with 11/28 patients (39%) in Group 2 (P less than 0.001) and 2/70 patients (3%) in Group 3 (P less than 0.001). Sonographic abnormality persisted beyond 32 weeks postpartum in 36/41 antibody positive patients (87%) who had exhibited thyroid hypoechogenicity earlier during the study and who had late scans. The characteristic US appearance in PPT is thyroid hypoechogenicity. The role of sonography in the prediction, diagnosis and follow up of patients with PPT is discussed.  相似文献   
46.
The pathogenesis of NC in VLBW infants appears to be multifactorial. The vulnerability of extreme immaturity and the underdevelopment of renal function may be the most important variables. In some ways, we view this problem as similar to that of retinopathy of prematurity. (Clearly the exposure of the retina to high partial pressures of oxygen contributes to the development of retinopathy of prematurity but other variables--some known, such as an immature retina, and others not yet defined--must be present.) Hypercalciuria is common in the VLBW infant, yet not all develop NC. Decreased glomerular filtration rate, low citrate excretion, and frequently an alkaline urine are in part due to the immaturity of renal function of these infants. The need for prolonged hyperalimentation resulting in increased oxalate excretion and the development of BPD frequently requiring diuretics that may cause phosphaturia and magnesium depletion and that may increase calcium excretion are more common in the smallest and sickest of premature infants. Even transient insults to the kidneys, such as hypoxia or hypotension or the use of nephrotoxic drugs that provoke tubular injury and cell death with the probability of crystal formation and growth by way of heterogeneous nucleation, are likely to occur more frequently in this vulnerable population.  相似文献   
47.
Following the toxicity and synthetic difficulties encountered with the hypoxic cell radiosensitizer RSU 1069, efforts have focused on development of a superior analogue. Two compounds, RB 6145 and PD 130908, have emerged from this program which overcome the instability and synthetic problems associated with RSU 1069 while retaining favorable biological activity. Both agents show comparable radiosensitizing activity to RSU 1069 following oral or i.p. administration to mice bearing the KHT or RIF-1 tumors. Sensitizing efficiency is about 10 X greater than that observed for misonidazole or etanidazole. Toxicity toward hypoxic tumor cells in vivo is demonstrated by clamping tumors (for 60 min) following administration of PD 130908 or RB 6145. Both are effective hypoxic cytotoxins, but less potent than RSU 1069. Systemic toxicity is substantially reduced following oral drug administration. Further, doses achievable following fractionated drug treatments are sufficiently high to produce significant levels of radiosensitization.  相似文献   
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In an effort to examine whether disturbed interpersonal relationships are associated with relapse in depression, discrepancies in self-ratings provided by formerly depressed patients and their collateral informants were compared. Thirty-eight remitted depressed patients and their collateral informants were asked to monitor moods, life events, and stress levels on a bimonthly basis for a 1-year period. It was hypothesized that patient/collateral dyads displaying a greater discrepancy in interpersonal perception would have a higher risk of relapse than dyads who showed more agreement in their ratings. Results indicated that while discrepancies in the perceptions of patients' life events were associated with the duration of a relapse once it occurred, discrepancies were generally not related to the emergence of new episodes of depressive disorder. The implications of these findings for models seeking to integrate cognitive and interpersonal models of depression, through the study of environmentally determined and personally appraised adversity, is discussed.This research was supported by grants to the first and third authors from the Canadian Psychiatric Research Foundation and the Laidlaw Foundation.  相似文献   
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