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alpha-Particle-emitting radionuclides, such as (211)At, with a 7.2-h half-life, may be optimally suited for the molecularly targeted radiotherapy of strategically sensitive tumor sites, such as those in the central nervous system. Because of the much shorter range and more potent cytotoxicity of alpha-particles than of beta-particles, (211)At-labeled agents may be ideal for the eradication of tumor cells remaining after surgical debulking of malignant brain tumors. The main goal of this study was to investigate the feasibility and safety of this approach in patients with recurrent malignant brain tumors. METHODS: Chimeric antitenascin monoclonal antibody 81C6 (ch81C6) (10 mg) was labeled with 71-347 MBq of (211)At by use of N-succinimidyl 3-[(211)At]astatobenzoate. Eighteen patients were treated with (211)At-labeled ch81C6 ((211)At-ch81C6) administered into a surgically created resection cavity (SCRC) and then with salvage chemotherapy. Serial gamma-camera imaging and blood sampling over 24 h were performed. RESULTS: A total of 96.7% +/- 3.6% (mean +/- SD) of (211)At decays occurred in the SCRC, and the mean blood-pool percentage injected dose was < or = 0.3. No patient experienced dose-limiting toxicity, and the maximum tolerated dose was not identified. Six patients experienced grade 2 neurotoxicity within 6 wk of (211)At-ch81C6 administration; this neurotoxicity resolved fully in all but 1 patient. No toxicities of grade 3 or higher were attributable to the treatment. No patient required repeat surgery for radionecrosis. The median survival times for all patients, those with glioblastoma multiforme, and those with anaplastic astrocytoma or oligodendroglioma were 54, 52, and 116 wk, respectively. CONCLUSION: This study provides proof of concept for regional targeted radiotherapy with (211)At-labeled molecules in oncology. Specifically, the regional administration of (211)At-ch81C6 is feasible, safe, and associated with a promising antitumor benefit in patients with malignant central nervous system tumors.  相似文献   
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A new catheter was used in an attempt to re-establish coronary flow in six patients with acute occlusion after angioplasty and prior to emergency coronary artery bypass surgery. All patients suffered from severe chest pain, and the electrocardiogram showed signs of acute transmural ischemia. A reperfusion catheter manufactured by Advanced Cardiovascular Systems (ACS) has 36 side holes spirally arranged along the distal 10 cm. It is introduced over an exchange wire. After the catheter was positioned across the occlusion, five patients had complete relief of chest pain, and another patient had partial relief. The electrocardiogram normalized in all six patients (in one only initially). Two patients developed a limited myocardial infarction, but four did not. The time between introduction of the reperfusion catheter and aorta cross clamping varied between 1.5 and 6.5 hours, and there were no complications related to its use. We conclude that the ACS reperfusion catheter is useful in re-establishing coronary blood flow after failed angioplasty and prior to emergency coronary artery bypass surgery.  相似文献   
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The volume of the nuclei and nucleoli of certain hypothalamic centers (SON, PVN, SCN, AN, VMN) was determined in control rats and in rats after deafferentation of the mediobasal hypothalamus. Sex differences were found in the parvocellular formations of the control animals: The volumes of nuclei and nucleoli of neurons of AN and VMN, and also of the nucleolus of SCN neurons were larger in females than in males. After deafferentation of the mediobasal hypothalamus the volume of the cell nuclei was increased, especially in hypothalamic formations located outside the isolated zone. This increase was more clearly defined in rats constantly in a state of estrus after the operation. Statistically significant differences between volumes of both nuclei and nucleoli of the cells in subgroups of rats with permanent estrus and with permanent diestrus were found only in the case of SCN. No such differences were found for AN, despite the considerable difference in the constant of luteinizing hormone in the pituitary of the same rats. It is suggested that gonadotropin releasing factors are not produced by the cells of AN and that control over the succession of phases of the sex cycle may be exerted by SCN.Laboratory of Neuroendocrinology, I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Chernigovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 3, pp. 352–354, March, 1980.  相似文献   
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Eighty-eight adenovirus (Ad) isolates and associated clinical data were collected from walk-in patients with influenza-like illness in Egypt during routine influenza surveillance from 1999 through 2002. Respiratory Ad distributions are geographically variable, and serotype prevalence has not been previously characterized in this region. Serotype identity is clinically relevant because it predicts vaccine efficacy and correlates strongly with both clinical presentation and epidemiological pattern. Species and serotype identities were determined using several well-validated multiplex PCR protocols culled from the literature and supplemented with a few novel primer sets designed to identify rare types. The isolates included common species B1 serotypes (Ad3 and Ad7), common species C serotypes (Ad1, Ad2, and Ad5), the less common species B2 serotype Ad11, and three isolates of the rare species B1 serotype Ad16. Two isolates that appear to be variant Ad16 were also identified. Fifteen coinfections of multiple adenoviral types, primarily AdB/AdC and Ad3/Ad7 dual infections, were detected. The majority of these were verified using redundant PCR tests targeted at multiple genes. PCR is able to resolve coinfections, in contrast to traditional serum neutralization tests. PCR is also comparatively rapid and requires very little equipment. Application of the method allowed an inclusive determination of the serotypes found in the Egyptian respiratory sample set and demonstrated that coinfections are common and may play a previously unrecognized role in adenovirus pathogenesis, evolution, and epidemiology. In particular, coinfections may influence adenoviral evolution, as interserotypic recombination has been identified as a source of emerging strains.  相似文献   
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Background  

The E-selectin p. S128R (g. A561C) polymorphism has been associated with the presence of angiographic coronary artery disease (CAD) in some populations, but no data is currently available on its association with CAD in Arabs.  相似文献   
9.
Evidence for the presence and potential co-existence of vasoactive intestinal polypeptide (VIP), pituitary adenylate cyclase-activating polypeptide (PACAP) and nitric oxide synthase (NOS) in gastro-intestinal endocrine cells and/or nerve fibers is conflicting and very few results exist on development. This immunofluorescence study aims to clarify the appearance and localization of VIP, PACAP and NOS in the gastro-intestinal tract of the Axolotl, Ambystoma mexicanum, during ontogeny. VIP-immunoreactivity appeared in nerve fibers as early as on day 3 after hatching likely indicating a particular role, such as a trophic action, of VIP in very early development. PACAP-immunoreactivity was observed 3 days later within the VIP-immunoreactive (-IR) fibers. From this time on, VIP- and PACAP-immunoreactivity exhibited complete co-existence. VIP/PACAP-IR fibers were found throughout the gastro-intestinal tract. They were most prominent in the myenteric plexus and the muscle layers and less frequent in the submucosa. NOS-immunoreactivity appeared as late as at the 1st (64 days) juvenile stage in a subpopulation of the VIP/PACAP-IR fibers that contacted submucosal arteries. We found only very few VIP/PACAP-IR perikarya, indicating that part of the VIP/PACAP-IR fibers is of extrinsic origin. On day 12 and in the 1st and 2nd (104 days) juvenile stage, infrequent PACAP-IR entero-endocrine cells were noted, while neither VIP- nor NOS-immunoreactivity occurred in endocrine cells at any stage of development. The complete coexistence of neuronal PACAP- and VIP-immunoreactivities and their very early appearance in ontogeny may suggest important and coordinated roles of both peptides in the control of Axolotl gastro-intestinal activity, while the VIP/ PACAP/NOS-IR fibers may be involved in the regulation of submucosal blood flow.  相似文献   
10.
INTRODUCTION: By the introduction of the laparoscopy for the management of gastric pathology many techniques are applied by now. In these techniques the collaboration of the endoscopist and the laparoscopic surgeon is mandatory. AIMS OF THE STUDY: To emphasise the necessity of the collaboration of the endoscopist and the laparoscopic surgeon for the management of the gastric pathology using the double lifting and wedge resection technique. METHOD: A case of a female with 2 x 2.5 cm submucosal tumour is presented. The tumour was located in the antrum. After the onset of the general anaesthesia the gastroscope was introduced to locate the position of the tumour, the free edges of the tumour were elevated by a double lifting method and the tumour was resected by a laparoscopic linear stapler. The process of the proper resection was all through observed and directed by the view of the gastroscope. CONCLUSION: Correct wedge resection of the gastric wall can be safely performed, if the correct gastroscopic control is present. The collaboration of the endoscopist and the laparoscopic surgeon seems to be mandatory, thus avoiding the hazards arising from the use of tattooing.  相似文献   
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