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1.
In a prospective randomised clinical study on 80 patients with idiopathic sudden hearing loss the therapeutic value of nimodipine was evaluated. Nimodipine is a 4-5-dihydropyridine calcium antagonist with selective spasmolytic and vasodilatory properties on cerebral vessels. The mean improvement of hearing (250, 500, 1000, 2000, 4000 Hz) amounted to 16.5 +/- 11.3 dB as compared with 18.6 +/- 10.2 dB achieved by standard treatment with hydroxyethyl starch (HAES) and naftidrofuryl. The difference is not significant (p greater than 0.2). These results together with the low rate of side effects indicate nimodipine as a therapeutic alternative in cases of hypertension, cardiac failure and allergic predisposition. The possible role of spontaneous recovery on one side and of specific parameters such as rheologic abnormalities or type of audiogram are discussed. They are important for a more sophisticated therapeutic approach towards sudden hearing loss.  相似文献   
2.
The anti-tumor activity and chemopreventive potential of four Ayurvedic herbs viz. Curcuma longa L., Ocimum sanctum L., Tinospora cordifolia (Wild) Miers ex Hook.f & Thomas and Zizyphus mauritiana Lam. were evaluated using Dalton Lymphoma ascites (DLA) tumor model in Swiss Albino mice. The outcome was assessed using survival time, peritoneal ascitic fluid (Tumor volume) and hematological indices as parameters. Animals were divided into five groups (n = 6) viz. one DLA control and four Herb + DLA treated groups. All the four herb + DLA groups were pre-treated with respective herbs for 7 days and hematological indices were measured for entire five groups. On day-8 animals were inoculated with 1×106 DLA cells i.p., and Herb + DLA groups were continued with oral herbal treatment for 21-days. Hematological parameters and tumor volume were assessed to find the effects of herbs. Short term in vitro cytotoxicity was determined by Trypan Blue exclusion method and LDH leakage assay using different concentrations of herbal extracts and 5-FU as a positive control and IC50 for each herbal extract and 5-FU were determined. Oral administration of crude herb increased the survival time and decreased the peritoneal ascitic fluid content significantly. Hb, RBCs and total WBC which were altered by DLA inoculation were restored significantly by all the herbs except O. sanctum. All the four herbs showed in vitro cytotoxic activity against DLA cell-line. Moreover inter group comparison of all the four herbs for anti-tumor activity showed efficacy in the following order- T. cordifolia > Z. mauritianaC. longa > O. sanctum respectively.  相似文献   
3.
BACKGROUND: Mast cells (MC) are important effector cells of allergic and inflammatory reactions in diverse organs. These cells interact with a number of other immune cells and structural cells in the tissues as well as with proinflammatory mediators and cytokines. The various interactions are considered to be mediated through distinct cell surface membrane receptors on MC. METHODS: In the present study, we have established the cell surface membrane phenotype of human gastrointestinal MC (HGMC) using a panel of monoclonal antibodies and indirect immunofluorescence staining techniques. RESULTS: HGMC were found to react with antibodies against CD29, CD33, CD44, CD45, CD47, CD54, CD55, CD58, CD63, CD117, CD147, CD151, CD172a, and CD203c. By contrast, HGMC did not express detectable amounts of CD1, CD2, CD4, CD5, CD14, CD15, CD16, CD22, CD24, CD25, CD26, CD27, CD28, CD31, CD32, CD34, CD35, CD88, or CD116. The alpha-chain of the IL-3 receptor (CD123) was detectable neither in resting HGMC nor in HGMC exposed to stem cell factor and interleukin-4. CONCLUSIONS: HGMC express a unique profile of surface antigens including the receptor for mast cell growth factor, adhesion-related molecules, and activation-linked membrane antigens.  相似文献   
4.
Zusammenfassung Die Messung otoakustischer Emissionen (OAE) wird für H?rscreeninguntersuchungen von Neugeborenen auf Empfehlung der NIH Consensus Conference im Jahre 1993 in den USA und Europa eingesetzt. Obwohl diese Messungen gegenüber anderen objektiven Me?verfahren einfacher durchzuführen sind, erfordert die Bedienung des Systems und die Interpretation der Ergebnisse speziell geschultes Personal. Ein allgemeines objektives H?rscreening in Deutschland hat sich bisher weder bei Neugeborenen noch bei Risikokindern durchgesetzt, obwohl es wünschenswert w?re, Kinder mit angeborener Innenohrschwerh?rigkeit (Inzidenz: 1–6 von 1000) m?glichst früh zu erfassen, zu therapieren und zu rehabilitieren. Der Echosensor bietet die M?glichkeit, TEOAE-Messungen mit kurzer Me?zeit durchzuführen und automatisiert zu bewerten. Sie k?nnten auch von angelerntem Personal durchgeführt werden. Um die Ergebnisse des Echosensors mit denen des konventionellen TEOAE-Me?ger?ts ILO88 zu vergleichen, wurden OAE-Messungen an 111 Neugeborenen von audiologisch geschulten Personen durchgeführt. Im Rahmen dieser Pilotstudie wurden Reliabilit?t und Validit?t der Messungen im Vergleich zum Goldstandard der Hirnstammaudiometrie bestimmt. Es zeigte sich eine sehr hohe übereinstimmung (Sensitivit?t 100%, Spezifit?t 93,3%) zwischen den Ergebnissen beider Methoden. Somit steht mit dem Echosensor ein OAE-Me?verfahren zur Verfügung, das eine hohe Sensitivit?t und Spezifit?t aufweist und zu einfach bedienen ist. Dieses Ger?t k?nnte einem fl?chendeckenden Einsatz des H?rscreenings in Deutschland den Weg ebnen. Eingegangen am 22. Dezember 1996 Angenommen am 9. Juli 1998  相似文献   
5.
HYPOTHESIS: Flat-panel based volume computed tomography could improve cochlear implant electrode evaluation in comparison with multislice computed tomography. BACKGROUND: Flat-panel based volume computed tomography offers higher spatial resolution and less metal artifacts than multislice computed tomography. Both characteristics could improve the evaluation of challenging but important questions in cochlear implantation assessment, such as an exact imaging of cochlea, osseous spiral lamina, electrode array position, and single electrode contacts. These questions are not currently fully answered by multislice computed tomography. METHODS: Four isolated temporal bone specimens were scanned in a current multislice computed tomography scanner and in two experimental flat-panel based volume computed tomography scanners before and after cochlea implantation. To compare flat-panel based volume computed tomography and multislice computed tomography, four features were rated according to the following criteria: 1) visibility of the cochlea; 2) visibility of the osseous spiral lamina; 3) discernibility of individual electrode contacts; and 4) the ability to determine the electrode array position relative to scala tympani and scala vestibuli. Layer-by-layer microgrinding pictures were used as the ground truth for verification of imaging findings. RESULTS: Flat-panel based volume computed tomography was superior to multislice computed tomography in all four features rated. The cochlea and facial nerve canal were much better delineated in flat-panel based volume computed tomography. The osseous spiral lamina and single electrode contacts were only visible in flat-panel based volume computed tomography. Assessment of implant position with regard to the cochlear spaces was considerably improved by flat-panel based volume computed tomography. CONCLUSION: Cochlear implantation assessment could be improved by flat-panel based volume computed tomography and, therefore, would be highly beneficial for cochlea implantation research and for clinical evaluation. However, these first results were shown by scanning isolated temporal bone specimens; scanning whole human skull bases might be more challenging.  相似文献   
6.
The auditory midbrain implant (AMI) is a new central auditory prosthesis designed for penetrating stimulation of the human inferior colliculus. The major group of candidates for the AMI consists of neurofibromatosis type 2 (NF2) patients who develop neural deafness because of growth and/or surgical removal of bilateral acoustic neuromas. Because of the absence of a viable auditory nerve, these patients cannot benefit from cochlear implants. An alternative solution has been the auditory brainstem implant (ABI), which stimulates the cochlear nucleus. However, speech perception performance in NF2 ABI patients has been limited. The fact that the ABI is able to produce high levels of speech perception in nontumor patients (with inaccessible cochleae or posttraumatic damage to the cochlear nerve) suggests that limitations in ABI performance in NF2 patients may be associated with cochlear nucleus damage caused by the tumors or the tumor removal process. Thus, stimulation of the auditory midbrain proximal to the damaged cochlear nucleus may be a better alternative for hearing restoration in NF2 patients. We propose the central nucleus of the inferior colliculus (ICC) as the potential site. A penetrating electrode array aligned along the well-defined tonotopic gradient of the ICC should selectively activate different frequency regions, which is an important elementfor supporting good speech understanding. The goal of this article is to present the ICC as an alternative site for an auditory implant for NF2 patients and to describe the design of the first human prototype AMI. Practical considerations for implementation of the AMI will also be discussed.  相似文献   
7.
Pathological auditory brainstem responses (lack of responses, elevated thresholds and perturbed waveforms) in combination with present otoacoustic emissions are typical audiometric findings in patients with a hearing impairment that particularly affects speech comprehension or complete deafness. This heterogenous group of disorders first described as “auditory neuropathy” includes dysfunction of peripheral synaptic coding of sound by inner hair cells (synaptopathy) and/or of the generation and propagation of action potentials in the auditory nerve (neuropathy). This joint statement provides prevailing background information as well as recommendations on diagnosis and treatment. The statement focuses on the handling in the german language area but also refers to current international statements.  相似文献   
8.
OBJECTIVE: To assess the efficacy of the combined oral contraceptive containing 3-mg drospirenone/20-microgram ethinyl estradiol (3-mg drospirenone/20-microgram ethinyl estradiol) administered as 24 consecutive days of active treatment after a 4-day hormone-free interval (24/4 regimen) compared with placebo for the treatment of moderate acne vulgaris. METHODS: Healthy females aged 14-45 years with moderate acne were randomized in this double-blind study to 3-mg drospirenone/20-microgram ethinyl estradiol (n=270) or placebo (n=268) for six cycles of 28 days. The primary outcome measures of acne lesion counts and Investigator Static Global Assessment scale ratings were assessed at baseline and during cycles 1, 3, and 6. RESULTS: The percentage reduction from baseline to endpoint for total lesions is 46.3% for 3-mg drospirenone/20-microgram ethinyl estradiol 24/4 combination oral contraceptive group and 30.6% for placebo group (P<.001). The likelihood of participants in the 3-mg drospirenone/20-microgram ethinyl estradiol 24/4 regimen group having "clear" or "almost clear" skin as rated by the investigators at endpoint was about threefold (odds ratio 3.13, 95% confidence interval 1.69-5.81; P=.001) greater than in the placebo group. The 3-mg drospirenone/20-microgram ethinyl estradiol 24/4 regimen was well tolerated. CONCLUSION: The low-dose combined oral contraceptive containing 3-mg drospirenone/20-microgram ethinyl estradiol administered in a 24/4 regimen significantly reduced acne lesion counts more effectively than placebo and demonstrated greater improvement in the Investigator Static Global Assessment rating of acne. The safety profile was consistent with low-dose combined oral contraceptive use.  相似文献   
9.
The use of hexapod circular external fixators has simplified the ability to correct complex limb deformities without cumbersome frame reconfigurations. These frames are applied primarily using half pin mountings and may be difficult to utilize given the constraints of traditional half pin constructs. We compared the biomechanical performance of simplified divergent half pin frames to mountings currently being utilized for application of hexapod frames. Three 6-mm half pins per limb segment were placed into sawbones at 60° divergent angles in both the sagittal and coronal planes in a 2-cm diaphyseal fracture gap model. Pin mountings were attached to a standardized four-ring construct. This was compared to similar four-ring frames with two differing pin/wire configurations: (1) two tensioned wires per ring placed at 90° angles, a total eight wires; and (2) two 5-mm half pins per ring placed at 90° angles, a total eight half pins. The divergent 6-mm half pin frames demonstrated similar performance compared the standardized tensioned wire and 5-mm half pin frames in terms of axial micromotion and angular deflection. Based on the mechanical performance of these divergent half pin frames we believe they can be used clinically without detrimental consequences. One or more of the authors (JTW) has received funding from Smith & Nephew.  相似文献   
10.
We report a case of synchronous olfactory bulb meningioma and undifferentiated carcinoma of the nose and paranasal sinuses that involved and destroyed the anterior skull base and mimicked intracranial invasion by a carcinoma. The heterogeneity of tissue types in the skull base gives rise to a diverse variety of benign and malignant neoplasms which have totally different prognoses. Synchronous development of benign and malignant primary tumors both originating from and involving the skull base at the same location is very rare and may cause confusion for both the skull base surgeon and neuroradiologist.  相似文献   
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