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71.
BACKGROUND: The standard therapy for patients with clinically resectable rectal cancer is generally considered to be surgery. If the patient is diagnosed with advanced disease, postoperative radio-chemotherapy (RCT) is usually recommended. In our study we aimed to investigate and analyze the effectiveness and toxicity of preoperative pelvic radiotherapy in combination with 5-fluorouracil (5-FU) in locally advanced rectal cancer. PATIENTS AND METHODS: From June 1999 to September 2001 we evaluated 50 consecutive patients [37 male and 13 female; average age 65.1 (range 46-79.5) years] with locally advanced rectal carcinoma. 32 patients were staged as uT3, 14 as uT4, and 4 as uT2. Regarding N-staging, 22 patients were diagnosed as uN0. 2 patients had distant metastases, with liver metastases in both instances. Conformal irradiation was performed with a box technique (4-field technique) with a dose of 45 Gy (5 x 1.8 Gy per week for a total of 25 sessions). From days 1-5 and 29-33, all patients received 5-FU (500 mg/m(2 ) per day, as a continuous i.v. injection). RESULTS: Remission was observed in 28 patients (56%), with down-staging of at least one T-stage. A better success rate was achieved for patients with deep-seated tumors (64% of the patients in this group). Complete remission was observed in 4 patients (8.0%) and progression in 3 (6.0%). 15 patients had no detectable change in tumor staging (30.0%). A surgical R0 resection could be achieved in 43 patients, an R1 resection (minimal margin) in 7. Side effects and toxicity (common toxicity criteria) of RCT included grade I-II dysuria in 5 patients (10%), grade I-II diarrhea in 20 patients (40%), and severe diarrhea in 2 patients (4.0%). Grade I-II skin reaction was noticed in 22 patients (44.0%), severe skin reaction only in 1 patient. Regarding acute postoperative morbidity, abscess and fistula formation was noted in 8 patients (16.0%), with anastomosis leakage in 7 (14%). CONCLUSION: Preoperative radiotherapy appears to be a feasible therapeutic approach with moderate toxicity and the potential to induce down-staging. The data presented in this study confirm the preliminary reports on this neoadjuvant treatment.  相似文献   
72.
Domoic acid (DA), a potent neurotoxin produced by select species of algae and diatoms, kills neurons bearing kainic acid-type glutamate receptors. Studies have shown that DA bioaccumulates in invertebrates and fish that consume the diatoms. In every vertebrate species tested or observed in the wild, dietary or systemic DA causes neuronal damage or clinical signs of neurotoxicity. Sharks, like marine birds and mammals, are exposed to DA through their diet; however, no research has demonstrated the effect of DA on shark behavior or physiology. In this study, juvenile leopard sharks (Triakis semifasciata) were given DA by intracoelomic injection at doses of 0, 1, 3, 9, and 27 mg/kg and observed for 7 days. The sharks failed to demonstrate behavioral or histological changes in response to the toxin. We identified putative brain glutamate receptors by probing western blots with an antibody specific for kainic acid-type glutamate receptors and demonstrated receptor localization in the cerebellum with immunohistochemistry. Blood levels of DA in three sharks dosed at 9 mg/kg fell rapidly within 1.5h of injection. We show that leopard sharks possess the molecular target for DA but are resistant to doses of DA known to be toxic to other vertebrates.  相似文献   
73.
5-Flourouracil(5-FU) is one of well known anti-cancer drugs, but its toxicity in normal lymphocytes remains a major problem in chemotherapy. The eastern traditional drug, Bupleuri radix(BR), has been used for the treatment of liver diseases and contains series of triterpene saponins.  相似文献   
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子宫肌瘤与性激素及细胞凋亡的关系   总被引:2,自引:0,他引:2  
周梅  付生军 《医学争鸣》2005,26(5):446-446
1对象和方法 1.1对象随机抽取2001-10/2002-09我科住院行子宫全切术的34例子宫肌瘤患者,其中卵泡期18例,黄体期16例,年龄35~45岁. 术后均经病理证实,在手术前3 mo均未接受过激素治疗,肌瘤大小为3~8 cm3. 自肌瘤瘤体及瘤旁肌层组织各取材1份作配对比较. 瘤体为实验组,肌层为对照组. 鼠抗人ER, PR, PRL-R, Bcl-2 mAb及链霉菌抗生物素蛋白-过氧化物酶(SP)免疫组化试剂盒,均购自福州迈新生物技术开发公司.  相似文献   
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77.
Transgenic mice with both alleles of the p53 tumor suppressor gene product 'knocked out' by gene targeting are susceptible to early development of tumors, chiefly lymphomas and sarcomas. Compared with the control group, administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male p53-deficient mice extended their lifespan by delaying death due to neoplasms (from 105 to 166 days on study, P = 0.002), primarily by suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P = 0.010). Treatment with a synthetic DHEA analog, 16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet also increased lifespan, to 140 days for mice that developed tumors (P = 0.037). The effects of these steroids on lifespan and tumor development did not appear to be strongly related to inhibition of food consumption and weight gain, in that a group pair-fed with control diet to the reduced food consumption of the DHEA-treated group developed and died of the same types of neoplasms at the same rate as the controls fed ad libitum. The chemopreventive effect of these steroids has been proposed to be due to suppression of DNA synthesis by inhibition of glucose 6-phosphate dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway. Although DHEA and its analog are strong non- competitive inhibitors of this enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide pools in the liver, as would have been predicted. The chemopreventive effect of DHEA in this model may be due to steroid-induced thymic atrophy and suppression of T cell lymphoma, permitting these mice to survive long enough to develop tumors with longer latency.   相似文献   
78.
Zusammenhang Unsere Daten zeigen eine enge Korrelation zwischen Null- und Rückw?rtsflu? in der Nabelarterie und fetaler Azidose, Hyperkapnie und Hyperlaktat?mie in wachstumsretardierenden Feten. Es besteht auch eine Assoziation zwischen abnormen umbilikalen Dopplerprofilen und Hypoxie. Ein Rückw?rtsflu? in der Nabelarterie ist mit einer deutlicheren Verschlechterung der respiratorischen und metabolischen Parameter verbunden als ein Nullflu?.  相似文献   
79.
Previous studies have observed an increased risk of approximately twofold or more for neural tube defects (NTD) associated with maternal obesity before pregnancy based on a body mass index (BMI) of > 29 kg/m2. No additional maternal factor appeared substantially to influence this association. Here, we explore further the association between BMI and NTD risk by considering the separate contributions of maternal prepregnant BMI and height. We also explore whether selected congenital anomalies, in addition to NTDs, were associated with maternal height or prepregnant BMI. Data were derived from two California population-based case-control studies. One study comprised 538 NTD cases and 539 non-malformed control infants. The other study included an additional 265 NTD cases, as well as 207 conotruncal cases, 165 limb anomaly cases, 662 orofacial cleft cases and 734 non-malformed controls. Maternal interviews in both studies elicited information on maternal height and prepregnant weight. Anomaly risk was described using additive linear logistic regression models. Results revealed increasing NTD risk with increasing maternal prepregnant BMI, controlling for maternal height. These patterns were observed overall as well as for most race/ethnic groups. Increasing NTD risk for decreasing height controlling for maternal BMI was also observed in one NTD study, but was not as evident in the other. Elevated risks for increasing maternal BMI and decreasing maternal height were not observed consistently for the other studied anomalies. The mechanisms underlying the association between maternal weight, or possibly maternal height, and NTD-affected pregnancy risk are unknown. Exploration of other data sets will be needed to determine whether similar patterns of NTD risk or lack of risk for other anomalies are associated with the two maternal anthropometric variables, height and prepregnant weight.  相似文献   
80.
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