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The superficial palmar arch (SPA) and its contributing arteries are highly variable. The palmar type of median artery (PMA) can be involved in the formation of the SPA by replacing the superficial palmar branch of the radial artery (RA) or the ulnar artery (UA). The present study was undertaken to investigate the presence of the PMA and its contribution in the formation of SPA in 42 cadavers (84 upper limbs) of Indian origin. When there was a PMA, its outer diameter was measured in the carpal tunnel. The PMA was found in 13 upper limbs (15.4%), and of these ten incidences (11.9%), the PMA took part in the formation of SPA, and in three instances (3.5%), the PMA did not make up part of the SPA. Out of the ten cases in which the PMA contributed to the formation of SPA, in six cases (7.1%), the PMA anastomosed with the UA; in three cases (3.5%), the PMA anastomosed with both the UA and the RA, and in one incidence (1.1%), the PMA joined the arteria radialis indicis (deep branch of the RA) to complete the SPA. The outer diameters of the median arteries varied between 0.8 and 2.6 mm with the mean value of 1.7 mm. The present study concludes that the median–ulnar type of SPA was the most common type of SPA when the PMA was encountered as a source of superficial arterial arcade of the hand, followed by the radial–median–ulnar type. The vascular patterns found in this study are important to hand surgeons. The present study of PMA origin, course, and its contribution to the SPA will add to the existing knowledge of the vascular anatomy of forearm and hand.  相似文献   
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Dens evaginatus (DE) and dens invaginatus (DI) are developmental anomalies that affect the shape of the teeth. Although they have been found singly and in association with other developmental anomalies in the same patient, it is uncommon to observe these two anomalies in the same tooth. There are only a few published cases of concurrent DI and DE in the same tooth. The patient in the case reported here was a 27-year-old man who exhibited a novel combination of DE and DI in permanent maxillary incisors. Early diagnosis of this anomaly is necessary. The clinician then can take particular care when performing prophylactic odontoplasty for the DE, keeping in mind that the associated DI presents an increased risk of early pulpal involvement. This article focuses on the management aspects of DE and DI.  相似文献   
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Prabhu VC  Bailes JE 《Neurosurgery》2002,50(1):195-7; discussion 197-8
OBJECTIVE AND IMPORTANCE: Soccer has become a popular sport, with more than 200 million Federation International Football Association-registered soccer players worldwide and 16 million participants in the United States. The risk of sustaining a significant head injury from a strike to a soccer ball with the head is unknown, but it may be increased with the presence of an underlying congenital arachnoid cyst. CLINICAL PRESENTATION: We describe the case of a 16-year-old female patient who sustained a large chronic and subacute subdural hematoma without a loss of consciousness from being struck on the head by a soccer ball. Because of the large size of the hematoma and her contralateral symptoms, surgery was performed. INTERVENTION: A temporal craniotomy for evacuation of a large chronic and subacute subdural hematoma with removal and fenestration of the arachnoid cyst resulted in resolution of her symptoms. Rigid craniotomy fixation of this small operative flap should allow the patient to return to soccer participation in the future. CONCLUSION: Although many may not consider soccer a contact sport, recent epidemiological data suggest that it is a common cause of sports-related concussion. In addition, as our case report demonstrates, there is a risk of significant intracranial injury and hematoma formation subsequent to a strike on the head by a soccer ball, and arachnoid cysts may contribute an additional risk of head injury.  相似文献   
57.
Rofecoxib is a highly active and selective cyclo-oxygenase II inhibitor. A stability-indicating method for the assay of rofecoxib has been developed using reverse-phase high-performance liquid chromatography (HPLC). Stress testing of rofecoxib was conducted during the method development and validation. HPLC analysis of rofecoxib solutions stressed under alkaline and photolytic conditions revealed the presence of several degradates. Two main degradates were determined to be the cyclization product formed by photo-cyclization and the dicarboxylate formed by ring opening in the presence of base and oxygen. The identities of these degradates were confirmed by comparison of UV spectra and HPLC retention time with the independently synthesized products. The mechanistic pathways for the formation of these degradates are discussed. Further improvement of the HPLC method's ruggedness has been made based on these studies.  相似文献   
58.
The objective of our study was to compare the in vitro release kinetics of a sustained-release injectable microsphere formulation of the polypeptide drug, calcitonin (CT), to optimize the characteristics of drug release from poly-(lactide-co-glycolide) (PLGA) copolymer biodegradable microspheres. A modified solvent evaporation and double emulsion technique was used to prepare the microspheres. Release kinetic studies were carried out in silanized tubes and dialysis bags, whereby microspheres were suspended and incubated in phosphate buffered saline, sampled at fixed intervals, and analyzed for drug content using a modified Lowry protein assay procedure. An initial burst was observed whereby about 50% of the total dose of the drug was released from the microspheres within 24 hr and 75% within 3 days. This was followed by a period of slow release over a period of 3 weeks in which another 10-15% of drug was released. Drug release from the dialysis bags was more gradual, and 50% CT was released only after 4 days and 75% after 12 days of release. Scanning electron micrographs revealed spherical particles with channel-like structures and a porous surface after being suspended in an aqueous solution for 5 days. Differential scanning calorimetric studies revealed that CT was present as a mix of amorphous and crystalline forms within the microspheres. Overall, these studies demonstrated that sustained release of CT from PLGA microspheres over a 3-week period is feasible and that release of drug from dialysis bags was more predictable than from tubes.  相似文献   
59.
PURPOSE: The purpose of this study was to ascertain the influence of dental appearance upon subjective ratings of personal characteristics, specifically social competence, intellectual ability, and psychologic adjustment. MATERIALS AND METHODS: A cross-sectional analytic interview study was conducted with 201 undergraduates. Each participant was asked to make judgments about the personal characteristics of the subject of a single color photograph. Eight photographs of four different men were used, each with one of two degrees of dental status (visible disease, no visible disease). Outcome measures were participants' judgments of the social competence, intellectual ability, and psychologic adjustment of the subjects of the photographs. RESULTS: Participants judged subjects with less dental disease to be more socially competent, to show greater intellectual achievement, and to have better psychologic adjustment. CONCLUSION: In the absence of other information, the judgments an individual makes concerning the personal characteristics of others are influenced by dental appearance.  相似文献   
60.
BACKGROUND: The small intestine is susceptible to free radical-induced damage and our earlier work has shown that surgical manipulation of the intestine results in generation of oxygen free radicals, leading to mucosal damage. Heat preconditioning has been shown to offer protection against various stresses including oxidative stress and this study looked at the effect of heat preconditioning on surgical manipulation-induced intestinal mitochondrial alterations. METHODS: Control and rats pretreated with heat were subjected to surgical manipulation by opening the abdominal wall and handling the intestine as done during laparotomy. Mitochondria were prepared from isolated enterocytes and structural and functional alterations were assessed. RESULTS: Surgical manipulation of the intestine resulted in mitochondrial alterations as seen by ultrastructural changes and altered lipid composition. Mitochondria were functionally impaired as evidenced by altered calcium flux, decreased respiratory control ratio, and increased tetrazolium dye reduction and swelling. Along with this, biochemical alterations such as increased lipid and protein oxidation were seen following surgical manipulation. Mild heat preconditioning of the animal prevented these damaging effects. CONCLUSIONS: These studies suggest that stress in the small intestine due to surgery can affect enterocyte mitochondrial structure and function and these effects can be prevented by mild whole body hyperthermia prior to surgery.  相似文献   
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