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991.
In humans, the sex of an individual is determined by the Y-chromosome-related SRY gene, which causes the differentiation of the undifferentiated gonads into testicular tissue. True hermaphrodites without a Y chromosome and XX males represent a sex determination error in which testicular tissue develops despite the absence of the SRY gene. Familial forms of XX true hermaphrodites and XX males exist in the literature, which also contains the two forms co-existing in the same family. In this report, we present a large family with seven affected individuals with phenotypes ranging from XX male to XX true hermaphrodite with predominance of female characteristics. We suggest that XX maleness and XX true hermaphroditism represent a continuum of the same disorder. We speculate on the mode of inheritance of this disorder in this particular family. Received: 15 May 2000 / Accepted: 5 July 2000  相似文献   
992.
The recent developments of nuclear medicine in oncology have involved numerous investigations of novel specific tumor-targeting radiopharmaceuticals as a major area of interest for both cancer imaging and therapy. The current progress in pharmaceutical nanotechnology field has been exploited in the design of tumor-targeting nanoscale and microscale carriers being able to deliver radionuclides in a selective manner to improve the outcome of cancer diagnosis and treatment. These carriers include chiefly, among others, liposomes, microparticles, nanoparticles, micelles, dendrimers and hydrogels. Furthermore, combining the more recent nuclear imaging multimodalities which provide high sensitivity and anatomical resolution such as PET/CT (positron emission tomography/computed tomography) and SPECT/CT (combined single photon emission computed tomography/computed tomography system) with the use of these specific tumor-targeting carriers constitutes a promising rally which will, hopefully in the near future, allow for earlier tumor detection, better treatment planning and more powerful therapy. In this review, we highlight the use, limitations, advantages and possible improvements of different nano- and microcarriers as potential vehicles for radionuclides delivery in cancer nuclear imaging and radiotherapy.  相似文献   
993.
The reaction of ethyl 4-(benzofuran-2-yl)-2,4-dioxobutanoate 2 with two moles of hydrazine hydrate afforded 5-(benzofuran-2-yl)-1H-pyrazole-3-carbohydrazide 4a, while its reaction with equimolar amount of phenylhydrazine gave ester 3b which then converted to 5-(benzofuran-2-yl)-1-phenyl-1H-pyrazole-3-carbohydrazide 4b. Various new compounds such as imides 5 and 6, acyl hydrazones 7 and 8, bi-pyrazoles 9-12, and 1,3-thiazole derivatives 14 and 15 were prepared from carbohydrazide derivatives 4a, b. The new compounds are tested for their antimicrobial activity. Compounds 2, 5, 7, and 8 showed antifungal activities against C. albicans. Also, compounds 2, 6, 8, and 15 showed antibacterial activities.  相似文献   
994.
In a previous study, we have described the elaboration of PLLA-based nanoparticles loaded with non radioactive dirhenium decacarbonyl [Re(2)(CO)(10)], a novel neutron-activatable radiopharmaceutical dosage form for intra-tumoral radiotherapy. These nanoparticles are designed for a neutron irradiation which can be carried out in a nuclear reactor facility. This new paper describes the neutron irradiation influence on these Re(2)(CO)(10)-loaded PLLA nanoparticles. The loaded nanoparticles with 23% (w/w) of metallic rhenium have shown to remain stable and separated and to keep out their sphericity at the lower neutron flux (1x10(11)n/cm(2)/s for 0.5h) which was used for rhenium content determination (neutron activation analysis, NAA). However, when loaded nanoparticles were irradiated at the higher neutron flux (1.45x10(13)n/cm(2)/s, 1h), they have shown to be partially coagglomerated and some pores appeared at their surface. Furthermore, DSC results showed a decrease in the PLLA melting point and melting enthalpy in both blank and loaded nanoparticles indicating a decrease in polymer crystallinity. In addition, the polymer molecular weights (M(n), M(w)) decreased after irradiation but without largely affecting the polymer polydispersity index (P.I.) which indicated that an irradiation-induced PLLA chain scission had occurred in a random way. The XRD patterns of irradiated PLLA provided another proof of polymer loss of crystallinity. FTIR spectra results have shown that irradiated nanoparticles retained the chemical identity of the used Re(2)(CO)(10) and PLLA despite the reduction in polymer crystallinity and molecular weight. Nanoparticles suspending after irradiation became also more difficult, but it was properly achievable by adding PVA (1%) and ethanol (10%) into the dispersing medium. Moreover, after 24h incubation of different irradiated nanoparticles in two different culture mediums, visual examination did not show bacterial growth indicating that applied neutron irradiation, yielding an absorbed dose of 450kGy, can be a terminal method for nanoparticles sterilisation. Thereafter, in a preliminary in vivo experiment, superparamagnetic non radioactive nanoparticles loaded with Re(2)(CO)(10) and oleic-acid coated magnetite have been successfully injected into a mice animal model via targeted multi therapy (TMT) technique which would be our selected administration method for future in vivo studies. In conclusion, although some induced neutron irradiation damage to nanoparticles occurs, dirhenium decacarbonyl-loaded PLLA nanoparticles retain their chemical identity and remain almost as re-dispersible and injectable nanoparticles by the TMT technique. These nanoparticles represent a novel interesting candidate for local intra-tumoral radiotherapy.  相似文献   
995.
996.
AIMS: The aim of this study is to evaluate meta-iodo-benzyl-guanidine scintigraphy in the diagnosis and the management of neuroblastoma. PATIENTS AND METHODS: betwen september 1999 and jun 2004, 16 children aging from 4 months to 6 years, with neuroblastoma, underwent mIBG scintigraphy in military hospital nuclear medicine department. RESULTS: 23 mIBG scans were done. The exam was indicated for the initial staging in 7 cases, to evaluate chemotherapy or surgery in 12 cases and to seek for reccurences in 3 cases. The sensitivity of mIBG was 57% in the detection of the primary tumor, 100% for liver metastases and 67% for medullar involvement. CONCLUSION: mIBG scintigraphy should be a standard in the initial staging of neuroblastoma and in evaluating therapy response.  相似文献   
997.
AIM: Our aim was to evaluate the indications and contribution of liver biopsy (LB) in intensive care (ICU) and to compare them to those of LB in gastroenterology. METHODS: We included retrospectively 37 successive LB achieved in ICU and 38 successive LB achieved in gastroenterology. All data were reviewed by three intensivists and three gastroenterologists to determine the contribution of the LB. RESULTS: The indications of LB were different in the two units. The most frequent indications were cirrhosis (36.8%), isolated biological hepatic disruptions (26.3%) and histological classification of viral hepatitis (18.4%) in gastroenterology and isolated biological hepatic disruptions (48.6%), hepatopathy during pregnancy (27%) and fever of unknown origin (10.8%) in intensive care unit. According to the six reviewers, LB was enough contributive in the two units, (78.4% in ICU and 71.1% in gastroenterology -p=0.46-). It allowed to eliminate, to confirm, or to change a diagnosis in more than 70% of cases and allowed to modify the course of therapy in 21.6% of cases in ICU and in 26.3% of cases in gastroenterology (p-0.6). CONCLUSION: The LB is a feasible technique in ICU and can be as contributive as it is in gastroenterology.  相似文献   
998.
Ventriculoperitoneal (VP) shunt surgery is the most widely used technique for the treatment of hydrocephalus. However, it can incur certain complications. Beside frequent complications (infection, obstruction), migration of the peritoneal catheter is a rare but dangerous complication. This report presents the case of a 4-year-old boy who had undergone VP shunt for hydrocephalus. One month later, the patient presented with protrusion of the peritoneal catheter through his mouth. He underwent another procedure to remove the peritoneal catheter, retaining the original ventricular catheter and valve chamber. Progression was favorable. To the best of our knowledge, only 7 cases of VP shunt transoral extrusion were reported, but many risk factors were identified. Bowel perforation is a serious complication of VP shunt surgery, sometimes leading to fatal outcome.  相似文献   
999.
1000.
Immunologic Research - Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by T cells imbalance. Indeed, a correlation between levels of Th17 cells and disease activity...  相似文献   
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