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1.
This brief review provides an overview of this topic; it is not a critical review. Polydrug use is a poorly defined concept; it is taken here to mean the simultaneous use of more than one drug. Data on polydrug use is seldom systematically collected, and the use of alcohol and tobacco in combination with illegal drugs is frequently overlooked. If alcohol and tobacco are included, most users are polydrug users, since these drugs are used by most users of illegal drugs, and many people with alcohol problems also use illegal drugs. Polydrug use has increased; drug availability, cultural context and the 'normalization' of drug use are important factors. Gender and racial differences are observed in the prevalence of polydrug use. Implications for drug prevention include the importance of targeting multiple substance use rather than single substances. Aiming prevention campaigns at younger people and focusing on 'gateway' drugs might be more effective. But polydrug users are diverse, and a variety of strategies (aimed at different types of polydrug users) are necessary. Implications for treatment include the evidence of the greater difficulty that polydrug users have in quitting; they may therefore require additional help. A fuller, systematic, review is required; it is expected that this would recommend the commissioning of additional research on this poorly understood phenomenon. 相似文献
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Preeti G. Lal Roopa S. Ghirnikar Lawrence F. Eng 《Journal of molecular neuroscience : MN》1996,29(1):93-104
Glial fibrillary acidic protein (GFAP) is the principal intermediate filament protein found in mature astrocytes. Although
the exact function of GFAP is poorly understood, it is presumed to stabilize the astrocyte’s cytoskeleton and help in maintaining
cell shape. Previous studies from our laboratory have shown that when astrocytes were cocultured with primary Schwann cells
(pSCs), astrocytes became hypertrophied and fibrous with intensely positive GFAP staining and segregated Schwann cells (SCs)
into pockets. In order to understand the functional role of GFAP in this already established astrocyte-SC coculture model,
we generated GFAP-negative cell lines from a GFAP-positive astrocytoma cell line and cocultured both the cell lines with pSCs.
Our studies demonstrate that the GFAP-positive cell line put out processes toward the SCs, whereas the GFAP-negative cells
did not form processes and the majority of the cells remained round. The most significant and interesting finding of this
study, however, is the formation of elaborate processes by SCs when grown in coculture with the astrocytoma cells, unlike
SCs cultured alone, which showed their typical bipolar spindle-shaped morphology. The extent of processes did not seem to
be dependent on GFAP, since SCs cultured with both the cell lines formed similar processes. This coculture model may be useful
in elucidating the factor(s) responsible for the formation of processes by SCs and can be further help in our understanding
of the mechanism of morphological transformation of SCs. 相似文献
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Vineet Relhan Rima R. Sahay Anita M. Shete Pragya D. Yadav Bijaylaxmi Sahoo Deepak Y. Patil Suresh Kumar Kannan Sabarinath Premachandran Syamaladevi Lalit Dar Sreelekshmy Mohandas Priya Abraham 《Journal of medical virology》2023,95(1):e28249
We describe the clinical and demographic characteristics, virological follow-up, and management of five confirmed monkeypox cases from New Delhi, India without any international travel history. The viral load kinetics and viral clearance were estimated in oropharyngeal swabs (OPS), nasopharyngeal swabs (NPS), EDTA blood, serum, urine, and various lesion specimens on every fourth day of follow-up ranging from 5 to 24 post onset day (POD) of illness. All five cases presented with mild to moderate-grade intermittent fever, myalgia, and lesions on the genitals, groins, lower limb, trunk, and upper limb. Four cases had non-tender firm lymphadenopathy. No secondary complications or sexually transmitted infections were recorded in these cases except for the presence of viral hepatitis B infection marker hepatitis B virus surface antigen (HBsAg) in one case. All the cases were mild and had a good recovery. A higher viral load was detected in lesion fluid (POD 9), followed by lesion roof (POD 9), urine (POD 5), lesion base (POD 5), and OPS/NPS (POD 5). The monkeypox virus (MPXV) DNA was detected in clinical samples from 5th to 24th POD. These monkeypox cases without international travel history suggest the underdiagnosed monkeypox infection in the community. This emphasizes the need for active surveillance of MPXV in the high-risk population such as men having sex with men and female sex workers. 相似文献
6.
Preeti Sharma Subha Rastogi Sunita Bhatnagar Janmejya K. Srivastava Anuradha Dube Purushottam Y. Guru Dinesh K. Kulshrestha Bishan N. Mehrotra Bhola N. Dhawan 《Drug development research》2003,60(4):285-293
Tephrosia purpurea (family: Fabaceae), which is used in traditional remedies for the treatment of febrile attacks, enlargement and obstruction of liver, spleen, and kidney, was found to have significant antileishmanial activity, and has been extensively fractionated to locate the abode of activity. A fraction (F062) obtained from N‐butanol extract of T. purpurea showed consistent antileishmanial activity at 50 mg/ kg × 5 days by oral route against Leishmania donovani infection in hamsters. Activity was further confirmed in a secondary model, i.e., Indian langur monkeys (Presbytis entellus). Thus, the fraction F062 from this plant possesses potential to produce significant antileishmanial activity by oral route without producing any toxic side effects. Drug. Dev. Res. 60:285–293, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
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Himanshu Yadav Snigdha Sen Tirupati Nath Shefali Mazumdar Anu Jain Pinky Verma Preeti Gupta 《Indian journal of ophthalmology》2022,70(6):2163
Purpose:An unprecedented surge has been noted in rhino-orbital-Cerebral mucormycosis (ROCM) in times of current COVID-19 pandemic. The present prospective study aims to evaluate clinico-epidemiological profile, risk factors, management, and outcome of the cases of ROCM that presented to our tertiary care center during the study period from April to June 2021.Methods:All patients were subjected to complete history taking, ophthalmological examination, and imaging studies. The patients were staged and were treated with intravenous liposomal amphotericin B (AMB) and sino-nasal debridement of local necrotic tissue. Transcutaneous retrobulbar AMB (TRAMB), orbital decompression, and exenteration were instituted as indicated. All patients were followed up for a minimum of 6 months before arriving at the final outcome. Statistical analysis was performed.Results:A total of 49 patients presented during the study period, with a mean age of 42.2 years. The major risk factors included uncontrolled diabetes (89.8%), COVID-19 positivity (51.02%), and concurrent steroid use (38.77%). The most common presenting symptom was facial pain/swelling (43.65%), while the most common presenting sign was deterioration in vision (75.51%). Intravenous liposomal AMB was given to all patients along with sino-nasal debridement (85.71%), TRAMB (57.14%), orbital decompression (14.28%), and exenteration (12.24%). Overall, mortality at 6 months was 22.45% (11 patients). Age more than 60 years, intracranial extension, and HbA1c of more than 8.0% were observed to be statistically significant indicators of mortality.Conclusion:Early suspicion and timely diagnosis of mucormycosis at rhino-orbital stage is warranted in order to salvage life as well as visual function. TRAMB may prove as potentially favorable treatment modality in cases with limited orbital involvement. 相似文献
9.
Preeti Kumari Omkara Swami Muddineti Sri Vishnu Kiran Rompicharla Pratyusha Ghanta Adithya Karthik B B N Balaram Ghosh 《Drug delivery》2017,24(1):209-223
Polymeric micelles have been widely explored preclinically as suitable delivery systems for poorly soluble chemotherapeutic drugs in cancer therapy. The present study reported the development of cholesterol (Ch)-conjugated poly(D,L-Lactide) (PLA)-based polymeric micelles (mPEG–PLA-Ch) for effective encapsulation and delivery of curcumin (CUR) at the tumor site. Cholesterol conjugation dramatically affected the particle size and improved drug loading (DL) and encapsulation efficiency (EE). mPEG–PLA-Ch-CUR showed bigger hydrodynamic diameter (104.6?±?2.1?nm, and 169.3?±?1.52?nm for mPEG–PLA and mPEG–PLA-Ch, respectively) due to increased size of the hydrophobic core. The newly developed polymer exhibited low critical micelles concentration (CMC) (25?μg/mL) which is close to lipid-based polymer, PEG-phosphatidyl ethanolamine (12.5?μg/mL) compared to mPEG–PLA (50?μg/mL). mPEG–PLA-Ch micelles exhibited relatively higher EE (93.74?±?1.6%) and DL (11.86?±?0.8%) compared to mPEG–PLA micelles (EE 91.89?±?1.2% and DL 11.06?±?0.8%). mPEG–PLA-Ch micelles were internalized by the cancer cells effectively and exhibited higher cytotoxicity compared to free CUR in both, murine melanoma (B16F10) and human breast cancer (MDA-MB-231) cells. mPEG–PLA-Ch exhibited satisfactory hemocompatibility indicating their potential for systemic application. Further, mPEG–PLA-Ch-CUR demonstrated higher rate of reduction of tumor volume in B16F10-xenografted tumor-bearing mice compared to free CUR. At the end of 22 days, the tumor reduced to 1.87-fold (627.72?±?0.9?mm3 versus 1174.68?±?1.64?mm3) compared to the treatment with free CUR. In conclusion, the experimental data in vitro and in vivo indicated that the newly developed CUR-mPEG–PLA-Ch micelles may have promising applications in solid tumors. 相似文献
10.
Pannu KK Chadha S Kumar D Preeti 《Indian journal of otolaryngology and head and neck surgery》2011,63(3):208-213
To evaluate and analyse the hearing loss in tympanic membrane perforation based on size, site and duration of perforation. The material for this study was comprised of 100 patients of either sex and of age 15?years and above selected randomly. Size of tympanic membrane perforation was assessed under microscope using calibrated wire look. Patients were divided into three groups according to size; group I (0-9?mm(2)), Group II (9-30?mm(2)), Group III (≥?30?mm(2)); according to site into anterior and posterior group; according to involvement of malleus into malleolar and non malleolar and according to duration into Group A (<1?year), Group B (1-5?years), Group C (≥?5?years). Hearing loss was measured in each case with pure tone audiometry. Data was analysed statistically using paired t-test. Hearing loss increased as the perforation size increased [I vs. II (t?-?4.23, p?0.001), II vs. III (t?-?8.19, p?0.001), I vs. III (t?-?11.68, p?0.001)]. Hearing loss was more in posterior quadrant perforation than anterior quadrant perforation but difference was not significant statistically (t?-?1.15, p?>?0.05). Hearing loss was more in malleolar perforation (t?-?5.74, p?0.001). Hearing loss increased as the duration of disease increased [A vs. B (t?-?2.01, p?0.043), A vs. C (t?-?5.49, p?0.001), B vs. C (t?-?4.14, p?0.001)]. 相似文献