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31.
Recent publications suggest the utility of temozolomide (TMZ) in the management of aggressive pituitary adenomas and carcinomas, resistant to conventional treatments. The response to TMZ is inversely correlated with tumoral expression of O-6 methylguanine DNA methyl transferase (MGMT). Therefore, we aimed to assess MGMT immunoexpression in pure GH-secreting pituitary adenomas, in an effort to predict the likelihood of response to TMZ, and to correlate MGMT immunoexpression with Ki-67 LI and cytokeratin (CK) distribution pattern. Our material consisted of 36 GH-secreting pituitary adenomas (21 female,15 male, mean age 42.5±10.5), operated at our center between 2003 and 2010. Immunostaining for MGMT, Ki-67, and CK was performed using avidin-biotin-peroxidase complex method. Immunoreactivity for MGMT and Ki-67 was evaluated microscopically and recorded as percentages of positive nuclear immunostaining. CK distribution pattern was also evaluated microscopically and assoreted into dot-like and nondot-like pattern subtypes. MGMT immunoexpression scored as 0=none, 1=<10%, 2=<25%, 3=<50%, and 4=>50%. Staining for MGMT was <10% (score 1) in 30 (83.3%), 10-25% (score 2) in 3 (8.3%), 25-50% (score 3) in 2 (5.6%) and >50% (score 4) in 1 (2.8%) of the tumors, respectively. There was no correlation between Ki-67 LI and CK distribution pattern with MGMT immunoreactivity (P>0.05). Data from the current study suggest a large proportion of GH-secreting adenomas, including those with dot-like CK distribution pattern and high Ki-67 LI, demonstrate negative/low MGMT immunoreactivity and could be treated with TMZ, if conventional treatment fails.  相似文献   
32.
Vecchini  F; Patrene  KD; Boggs  SS 《Blood》1993,81(6):1489-1496
Mouse bone marrow (BM) was separated into low-density, lineage- negative, wheat germ agglutinin-positive (WGA+), Rhodamine-123 bright (Rhbright) or dim (Rhdim) cells to obtain populations that were highly enriched for committed progenitors (Rhbright cells) or for more primitive stem cells (Rhdim). When 2,500 Rhbright or Rhdim cells were seeded onto 6-week-old irradiated (20 Gy) long-term BM cultures (LTBMC), the nonadherent cell production from Rhbright cells was transient and ended after 5 weeks. Production from Rhdim cells did not begin until week 3, peaked at week 5, and ended at week 8, when the irradiated stroma seemed to fail. Termination of cell production from Rhdim cells did not occur in nonirradiated LTBMC from W41/Wv mice. During peak nonadherent cell production, 25% to 30% of the cells in the nonirradiated LTBMC from W41/Wv mice had donor cell markers. Two approaches were tested to try to enhance the proportion or number of donor cells. Addition of Origen-HGF at the time of seeding Rhdim cells caused a nonspecific increase in both host and donor cell production, but a specific increase in production of donor cells was obtained by seeding the cultures at 2 weeks rather than 6 weeks. Limiting dilution of Rhdim cells gave the same frequency of wells producing cells on both irradiated +/+ and nonirradiated W41/Wv or W/Wv cultures.  相似文献   
33.
对QT离散度实质的探讨   总被引:2,自引:0,他引:2  
为探讨QT离散度(QTd)的真实意义,观察139例急性心肌梗死(AMI,AMI组)及109例正常人(对照组)的最长QT间期(QTmax)、校正QTmax(QTcmax)及QTd的变化。结果:①AMI组的QTmax、QTcmax和QTd均显著高于对照组(分别为422.60±30.51msvs382.46±23.40ms、460.21±28.96msvs388.51±20.15ms、59.80±28.40msvs39.43±12.21ms,P均<0.001)。②AMI组中发生严重室性心律失常(VA)患者(114例)的QTmax、QTcmax、QTd与无VA的患者(25例)相比,均有显著差异(分别为448.58±33.40msvs416.10±35.30ms、481.43±35.17msvs439.60±27.10ms、66.90±20.72msvs48.32±23.61ms,P均<0.001)。认为AMI时QTd系T向量环在不同导联上的“投影”差异所引起的,其异常的本质是QT间期延长  相似文献   
34.
Hepatic spiral CT: reduction of dose of intravenous contrast material   总被引:13,自引:0,他引:13  
  相似文献   
35.
O'Connor  MK; Brennan  SS; Shanik  DG 《Radiology》1986,158(1):191-194
The incidence of thromboembolitic events in patients undergoing transfemoral angiography was examined using indium-111 labeled platelets. Twenty-seven patients received approximately 300 muCi of autologous labeled platelets at least 3 hours before angiography and were scanned with a gamma camera immediately before and after angiography. All patients were free of clinically obvious complications in the 1-2 day period after angiography. Our results showed evidence of platelet deposition at 21 sites other than the puncture site in 12 (44%) patients. Most platelet deposition (54%) occurred along the region between the puncture site and the aortic bifurcation; 24% occurred at sites not traversed by the catheter. At the puncture site itself, there was substantial platelet uptake in 44% of patients. This study indicates the need for further work in determining the most suitable catheter material and in assessing the efficacy of other measures such as anticoagulant or antiplatelet therapy.  相似文献   
36.
Trabecular bone mineral density (TBMD) was measured in vivo in the calcaneus by a new method that uses the ratio of coherent to Compton-scattered photons arising from irradiation of a small volume of trabecular bone by a gamma ray source with highly collimated geometry. TBMD values for healthy men (22-77 years) were in the range of 180-357 mg/ml, and values for healthy women (18-73 years) were in the range of 160-321 mg/ml. In contrast, values in a small group of paraplegics were in the range of 90-199 mg/ml.  相似文献   
37.
黄柏及中成药中小檗碱和巴马亭的高效液相色谱法测定   总被引:6,自引:0,他引:6  
本文以正相高效液相色谱法,用窗口图解技术对色谱条件进行了优化。对黄柏及其中成药中的有效成分——小檗碱、巴马亭的提取、测定条件、标准曲线进行了研究。并对两种含黄柏的中成药样品进行了分析。其中小檗碱的回收率均在97%以上,巴马亭的回收率均在96%以上。  相似文献   
38.
39.

Background

The ethnic usage of exotics and indigenous problem plants is a highly debated topic, as legislative requirements over-shadow their potential medicinal value, particularly to treat sexually transmitted infections (STIs). Limited information exists regarding their medicinal value among the Bapedi.

Objectives

To ascertain the importance of exotics and indigenous problem plants in the treatment of STIs, a major global primary health care challenge.

Methods

A field observation and semi-structured questionnaire focussing on species diversity, types of STIs treated and medicinal preparation as well as application was used to collect data from 34 traditional healers.

Results

Seven exotics and three indigenous problem species were identified. These species were used to treat four STIs; with Catharanthus roseus illustrating its dominance in the treatment of gonorrhoea. Some medicinal species used by Bapedi traditional healers have been validated through scientific research or through their extensive use by various cultures in South Africa and other parts of Africa. To the best of our knowledge Alternanthera pungens, Caesalpinia decapetala, Cinnamomum verum, and Citrullus lanatus are reported for the first time in the treatment of the investigated STIs.

Conclusions

Exotic and indigenous problem species constitute an important component of the STIs treatment protocol. Their utilization by Bapedi cautions against the narrow-minded approach of indiscriminate eradication, as these species can play a significant role in the primary health care needs of socio-economic vulnerable people.  相似文献   
40.
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