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21.
Hajj Hussein IA Tohme R Barada K Mostafa MH Freund JN Jurjus RA Karam W Jurjus A 《World journal of gastroenterology : WJG》2008,14(25):4028-4039
AIM:To develop a novel model of colitis in rats, using a combination of iodoacetamide and enteropathogenic E. coli(EPEC), and to elucidate the pathophysiologic processes implicated in the development of ulcerative colitis (UC).
METHODS: Hale Sprague-Dawley rats (/7 = 158) were inoculated intrarectally on a weekly basis with 4 different combinations: (a) 1% methylcellulose (HC), (b) 100 μL of 6% iodoacetamide (IA) in 1% HC, (c) 200 p.L containing 4×10^8 colony factor units (CFU) of EPEC, and (d) combined treatment of (IA) followed by bacteria (13) after 2 d. Thirty days post treatment, each of the four groups was divided into two subgroups; the inoculation was stopped for one subgroup and the other subgroup continued with biweekly inoculation until the end of the experiment. Colitis was evaluated by the clinical course of the disease, the macroscopic and microscopic alterations, activity of myeloperoxidase (HPO), and by TNF-α gene expression. RESULTS: Findings indicative of UC were seen in the combined treatment (IA + B) as well as the IA continued treatment groups: the animals showed slow rate of increase in body weight, diarrhea, bloody stools, high colonic ulcer score, as well as histological alterations characteristic of UC, with an extensive inflammatory reaction. During the course of the experiment, the MPO activity was consistently elevated and the TNF-α gene expression was upregulated compared to the control animals.
CONCLUSION: The experimental ulcerative colitis model used in the present study resembles, to a great extent, the human disease. It is reproducible with characteristics indicative of chronicity. 相似文献
METHODS: Hale Sprague-Dawley rats (/7 = 158) were inoculated intrarectally on a weekly basis with 4 different combinations: (a) 1% methylcellulose (HC), (b) 100 μL of 6% iodoacetamide (IA) in 1% HC, (c) 200 p.L containing 4×10^8 colony factor units (CFU) of EPEC, and (d) combined treatment of (IA) followed by bacteria (13) after 2 d. Thirty days post treatment, each of the four groups was divided into two subgroups; the inoculation was stopped for one subgroup and the other subgroup continued with biweekly inoculation until the end of the experiment. Colitis was evaluated by the clinical course of the disease, the macroscopic and microscopic alterations, activity of myeloperoxidase (HPO), and by TNF-α gene expression. RESULTS: Findings indicative of UC were seen in the combined treatment (IA + B) as well as the IA continued treatment groups: the animals showed slow rate of increase in body weight, diarrhea, bloody stools, high colonic ulcer score, as well as histological alterations characteristic of UC, with an extensive inflammatory reaction. During the course of the experiment, the MPO activity was consistently elevated and the TNF-α gene expression was upregulated compared to the control animals.
CONCLUSION: The experimental ulcerative colitis model used in the present study resembles, to a great extent, the human disease. It is reproducible with characteristics indicative of chronicity. 相似文献
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Habib N Maniatis T Ahmed S Kilkenny T Alkaied H Elsayegh D Chalhoub M Harris K 《Heart & lung : the journal of critical care》2012,41(5):509-511
BACKGROUND: Because of the aging of the American population, osteoporotic vertebral fractures are becoming a common problem in the elderly. Minimally invasive percutaneous vertebral augmentation techniques have gained a great deal of importance in relieving the pain associated with these fractures, and are becoming the standard of care. METHODS: These procedures involve the injection of polymethylmethacrylate (PMMA) into the vertebral body. However, these techniques have their complications, and among these, pulmonary embolism is one of the most feared. It is attributable to the passage of cement into the pulmonary vasculature. After encountering a case of PMMA embolism in our practice, we decided to highlight this topic and discuss the incidence, clinical presentation, diagnosis, and treatment of cement pulmonary embolisms. 相似文献
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Purpose: The aim of this study was to determine effect of compressive cyclic loading on fatigue resistance and microleakage of monolithic CAD/CAM molar ceramic and composite crowns. Materials and Methods: Thirty‐two extracted molars were prepared to receive CEREC crowns according to manufacturer's guidelines using a special paralleling device (Parallel‐A‐Prep). Sixteen feldspathic ceramic crowns (VITABLOCS Mark II) (VMII) and 16 resin‐composite crowns (Paradigm‐MZ100 blocks) (PMZ) were milled using a CEREC‐3D machine. Eight crowns of each group were cemented to their respective teeth using self‐etching resin cement (Panavia‐F‐2.0) (PAN), and eight were cemented using self‐adhesive resin cement (RelyX‐Unicem‐Clicker) (RXU). Following storage for 1 week in water, specimens were subjected to uniaxial compressive cyclic loading in an Instron testing machine at 12 Hz for 1,000,000 cycles. Load was applied at the central fossa, and the cycle range was 60–600 N. Specimens were then subjected to microleakage testing. Data were statistically analyzed using factorial ANOVA and Post Hoc (Tukey HSD) tests. Results: All composite crowns survived compressive cyclic loading without fracture, while three ceramic crowns from the subgroup cemented with RXU developed surface cracks at the center of occlusal surfaces, extending laterally. Microleakage scores of ceramic crowns cemented with PAN were significantly lower than those of the other three subgroups (p < 0.05). Conclusions: After 1,000,000 cycles of compressive cyclic loading, PMZ composite molar crowns were more fatigue‐resistant than VMII ceramic crowns. Cement type had a significant effect on fatigue resistance of the ceramic crowns but not the composite ones. Microleakage scores of ceramic crowns cemented with PAN were significantly lower than those of the other subgroups (p < 0.05). 相似文献
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Compared with other breast cancer subtypes, patients with triple‐negative breast cancer (TNBC), and irrespective to their disease stage, were always recognized to have the worst overall survival data. Although this does not seem different at the present time, yet the last few years have witnessed many breakthrough genomic and molecular findings, that could dramatically improve our understanding of the biological complexity of TNBC. Based on genomic analyses, it was consistently evident that TNBC comprises a heterogeneous group of cancers, which have numerous diverse molecular aberrations. This—in return—has provided a platform for a new generation of clinical trials using many innovative therapies, directed against such novel targets. At the present time, two PARP inhibitors and one anti‐PD‐L1 monoclonal antibody (in combination with chemotherapy) have been approved in certain subpopulations of metastatic TNBC (mTNBC) patients, which have finally brought this disease into the era of personalized medicine. In the current review, we will explore the genomic landscape of TNBC, through which many actionable targets were graduated. We will also discuss the results of the key—practice changing—clinical studies, and some upcoming personalized treatment options for patients with mTNBC, that may be clinically adopted in the near future. 相似文献
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This work aims to prepare sustained release buccal mucoadhesive tablets of buspirone hydrochloride (BH) to improve its systemic bioavailability. The tablets were prepared according to 5 × 3 factorial design where polymer type was set at five levels (carbopol, hydroxypropyl methylcellulose, sodium alginate, sodium carboxymethyl cellulose and guar gum), and polymer to drug ratio at three levels (1:1, 2:1 and 3:1). Mucoadhesion force, ex vivo mucoadhesion time, percent BH released after 8 h (Q8h) and time for release of 50% BH (T50%) were chosen as dependent variables. Additional BH cup and core buccal tablets were prepared to optimize BH release profile and make it uni-directional along with the tablets mucoadhesion. Tablets were evaluated in terms of content uniformity, weight variation, thickness, diameter, hardness, friability, swelling index, surface pH, mucoadhesion strength and time and in vitro release. Cup and core formula (CA10) was able to adhere to the buccal mucosa for 8 h, showed the highest Q8h (97.91%) and exhibited a zero order drug release profile. Pharmacokinetic study of formula CA10 in human volunteers revealed a 5.6 fold increase in BH bioavailability compared to the oral commercial Buspar® tablets. Conducting level A in vitro/in vivo correlation showed good correlation (r2 = 0.9805) between fractions dissolved in vitro and fractions absorbed in vivo. 相似文献
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