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A case of destructive ocular myiasis resulting in complete loss of the globe in two days time is documented. To the best of our knowledge this is the first report of such a severe involvement in a healthy and non-compromised host. Mechanical removal and good local hygiene helped heal the wound. The larvae were isolated to be that of Chrysomyia bezziana (screwworm fly). This is possibly the first report of destructive ocular myiasis caused by Chrysomyia bezziana from the Indian subcontinent and the second in world literature. Infestation of human eyes with larvae of flies (myiasis) has been reported. Serious consequences of destructive myiasis are seen in emaciated and diseased patients. Only one report of total destruction of the globe by maggots of Chrysomyia bezziana exists in the literature. As in previous communications, the patient in this report had no predisposing factors both systemic and local. We here in document a case of orbital myiasis leading to rapid destruction of the globe within two days in a healthy and a non-compromised patient.  相似文献   
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We used the patch-clamp method to characterize the BK channel in freshly isolated myocytes from the saphenous branch of the rat femoral artery. Single-channel recordings revealed that the BK channel had a conductance of 187 pS in symmetrical 150 mM KCl, was blocked by external tetraethylammonium (TEA) with a KD(TEA) of approx. 300 microM at +40 mV, and by submicromolar charybdotoxin (CTX). The sensitivity of the BK channel to Ca was especially high (KD(ca) approx. 0.1 microM at +60 mV) compared to skeletal muscle and neuronal tissues. We also investigated the macroscopic K current, which under certain conditions is essentially sustained by BK channels. This conclusion is based on the findings that the macroscopic current activated upon depolarization follows a single exponential time course and is virtually fully blocked by 100 nM CTX and 5 mM external TEA. We made use of this occurrence to assess the voltage and Ca dependence of the macroscopic BK current. In intact myocytes, the BK channel showed a strong and voltage-dependent reduction of the outward current (62% at +40 mV), most likely due to block by intracellular Ba and polyamines. The results obtained from macroscopic and unitary current indicate that approx. 2.5% of the BK channels are active under physiological conditions, sustaining approx. 20 pA of outward current. Given the high input resistance of these cells, few BK channels are required to open in order to cause a significant membrane hyperpolarization, and thus function to limit the contraction resulting from acute increases in intravascular pressure, or in response to hypertensive pathologies.  相似文献   
4.
Indications for pediatric keratoplasty in India.   总被引:4,自引:0,他引:4  
T Dada  N Sharma  R B Vajpayee 《Cornea》1999,18(3):296-298
PURPOSE: To study the associations and indications for pediatric keratoplasty. METHODS: We undertook a retrospective analysis of 415 grafts performed in 393 children, aged 12 years or younger between January 1993 and December 1997. The parameters evaluated were demographic data, socioeconomic status, preoperative diagnosis, and any systemic or ocular associations. RESULTS: Of the 415 eyes operated on, 296 (71.32%) eyes underwent keratoplasty for acquired nontraumatic corneal opacities, 51 (12.28%) had congenital corneal conditions, 45 (10.85%) were regrafts, and 23 (5.54%) eyes had acquired traumatic corneal opacities. The cause of corneal opacification in the acquired nontraumatic group was infectious keratitis in 215 (72.63%) eyes and keratomalacia in 81 (27.36%) eyes. Systemic associations with the onset of the opacity in the acquired nontraumatic group were fever in 74 (25%) cases, diarrhea in 56 (18.9%) cases, and malnutrition in 98 (33.1%) cases. Seventeen (4.32%) children belonged to the lower middle class, 64 (16.28%) were in the upper lower class, and 312 (79.38%) were from the lower socioeconomic families based on the Kuppuswamy scale. CONCLUSIONS: Infectious keratitis is the major indication for pediatric keratoplasty in India. In the majority of the cases, the occurrence of corneal opacification is associated with poverty.  相似文献   
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The aim of this 4-year audit was to establish whether sessile serrated polyps/adenomas (SSP/A) were diagnosed in a district general hospital in the UK. The study also explored whether SSP/A in the right colon were misdiagnosed as hyperplastic polyps. A retrospective search of the computer records from 2009 to 2012 inclusive for all lesions diagnosed and coded as SSP/A and/or hyperplastic polyps proximal to the splenic flexure was undertaken. All slides were reviewed and a diagnosis of SSP/A made using the criteria recently suggested by the American College of Gastroenterology. Over the study period, no cases of SSP/A were made. On review of all hyperplastic polyps proximal to the splenic flexure, 13/31 in 2009, 17/40 in 2010, 19/48 in 2011 and 16/48 in 2012 were re-classified as SSP/A. The most likely reason for the under-diagnosis of SSP/A is lack of awareness of the lesion both clinically and by pathologists. Adequate biopsies and deeper sections are important to help make the diagnosis of SSP/A. This study shows that SSP/A are reasonably frequently encountered in non-specialist practice settings and that both clinicians and pathologist in this setting need to be aware of its existence.  相似文献   
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Background  

The first-ever round of school-based mass drug administration (MDA) with praziquantel together with mebendazole targeting school-aged children in endemic districts was conducted in 2009 by the National Neglected Tropical Diseases Control Program. To evaluate the impact of the treatment regimen, a cross-sectional sentinel site survey was conducted 6 months post-MDA.  相似文献   
9.
The protective role of gallic acid (GA) on reproductive toxicity induced by cyclophosphamide (CPA), an antineoplastic drug, was investigated in male Wistar rats. Sixty rats were grouped into 10 rats per group. Group 1 (control) received distilled water. Rats in groups 2 and 3 received GA alone at 60 and 120 mg kg?1 for 14 consecutive days, respectively. Group 4 received a single intraperitoneal dose of CPA at 200 mg kg?1 on day 1. Groups 5 and 6 received a single dose of CPA (200 mg kg?1) intraperitoneally on day 1 followed by treatment with GA at 60 and 120 mg kg?1 for 14 consecutive days, respectively. In testes and epididymis of the treated rats, CPA administration resulted in significant elevation (P < 0.05) in malondialdehyde (MDA), nitrite and hydrogen peroxide levels. There was a significant decrease in the activities of superoxide dismutase and glutathione‐S‐transferase. Furthermore, there were significant reductions in plasma luteinising hormone (LH), follicle stimulation hormone (FSH) and testosterone levels, which were accompanied by significant decrease in sperm motility and viability in CPA‐treated rats. Histological examination revealed marked testicular and epididymal atrophy in CPA alone treated rats and these aberrations were reversed by GA. In conclusion, GA has capacity to protect against reproductive toxicity induced by cyclophosphamide.  相似文献   
10.
BACKGROUND: Varicocele is the most common cause of male infertility. The etiology and pathophysiology of varicocele are multifactorial. When low sperm counts are associated with varicocele, varicocelectomy can partially restore spermatogenesis and fertility. Few recent studies have reported that in some varicocele cases, there may be an associated genetic etiology. Presence of a genetic factor like azoospermia factor microdeletions may lead to irreversible spermatogenic arrest in these cases, but very few reports support these findings. However, it is still not understood why some cases improve after varicocelectomy and why some cases show no improvement in semen parameters postoperatively. AIM: It is important to distinguish varicocele cases from Yq microdeletions as these cases have irreversible testicular damage and thus carry a poor prognosis after varicocelectomy. SETTINGS: Research and Referral tertiary care hospital. Design: Prospective study. MATERIALS AND METHODS: Seventy-two infertile men with varicocele were referred for Yq microdeletion analysis from the infertility clinic of AIIMS and Army Research and Referral Hospital. Genomic DNA was isolated from blood and polymerase chain reaction microdeletion screening was done in these cases to determine the presence or deletion of AZF loci. RESULTS: In this study 7 (9.7%) varicocele cases harbored Yq microdeletion. The sperm count in cases which harbored Yq microdeletion was significantly lower than in cases without Yq microdeletion. CONCLUSION: Varicocele cases with Yq microdeletion do not show improvement in semen parameters post-varicocelectomy. Detection of Yq microdeletion determines prognosis and future management in such cases.  相似文献   
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