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171.
INTRODUCTION: Microparticulate drug delivery systems have, due to their advantages, guided researchers across the globe to explore them as drug carriers. This has, sequentially, led to the development of microsponges in 1988. These porous microspheres were exclusively designed for chronotherapeutic topical drug delivery but attempts to utilize them for oral, pulmonary and parenteral drug delivery were also made. Researchers have extensively studied their properties and characteristics affecting the drug release and loading. Various advances were made with this carrier particle resulting in the development of various novel development techniques and carrier particles. AREAS COVERED: This review deals with the considerations of the drug material to be entrapped in microsponges, pharmaceutical considerations for fabrication of microsponges, their potential for oral drug delivery, clinical perspectives and also provides an insight on the recent advances made in this field and future prospect. EXPERT OPINION: Clinical studies show that these carriers can increase drug efficacy. Due to their potential advantages over other carrier particles, microsponges form a prospective platform for the oral delivery of pharmaceuticals and biopharmaceuticals. Although these carriers have several advantages, they too possess some drawbacks which limit their commercialization for oral application.  相似文献   
172.
Objective. To evaluate the impact of counseling in a simulated medication adherence activity.Design. Students were randomized into 2 groups: patient medication monograph only (PMMO) and patient medication monograph with counseling (PMMC). Both groups received a fictitious medication and monograph. Additionally, the PMMC group received brief counseling. A multiple-choice, paper-based survey instrument was used to evaluate simulated food-drug interactions, adherence, and perceptions regarding the activity’s value and impact on understanding adherence challenges.Assessment. Ninety-two students participated (PMMC, n=45; and PMMO, n=47). Overall, a significantly higher incidence of simulated food-drug interactions occurred in the PMMO group (30%) vs the PMMC group (22%) (p=0.02). Doses taken without simulated food-drug interactions were comparable: 46.2% (PMCC) vs 41.9% (PMMO) (p=0.19). The average number of missed doses were 3.2 (PMMC) vs 2.8 (PMMO) (p=0.55). Approximately 70% of the students found the activity to be valuable and 89% believed it helped them better understand adherence challenges.Conclusion. This activity demonstrated the challenges and important role of counseling in medication adherence.  相似文献   
173.
Vitex negundo is a common herb in different herbal formulation. The potential acute and sub-chronic dermal toxicities were evaluated as per OECD (Organization for Economic Cooperation and Development) guidelines 402 and 411, respectively. Both sexes of Wistar rats were exposed to Vitex negundo oil of 2000?mg/kg body weight for acute dermal toxicity, whereas in the dermal sub-chronic toxicity study, rats were exposed to Vitex negundo oil 250, 500 and 1000?mg/kg body weight, respectively, for five times a week for 90?d. In acute and sub-chronic toxicity studies, all animals were normal without any behavioral, serum biochemistry, hematology, necroscopical and histopathological changes. The no observed effect level (NOEL) and no observed adverse effect level (NOAEL) of Vitex negundo oil were 250 and 1000?mg/kg/day, respectively. Vitex negundo oil is under the category 5 (Unclassified) according to the Globally Harmonized System, with an LD50 value of over 2000?mg/kg.  相似文献   
174.
Novel Schiff bases of N-substituted isatin, 1–13, were synthesized starting from isatin and N-(4-amino-2-methylphenyl)-4-chlorophthalimide and their structures were confirmed by spectral and elemental analyses. All new compounds were tested for their in vitro antibacterial activity against a range of Gram +ve bacterial strains, like Bacillus subtilis (NCIM-2156), Staphylococcus aureus (NCIM-2079) and Staphylococcus epidermis (NCIM-2493) and Gram ?ve bacterial strains, like Pseudomonas aeruginosa (NCIM-2036), Escherichia coli (NCIM-2065) and Proteus vulgaris (NCIM-2027) following broth dilution method as recommended by the National Committee for clinical laboratory standards using ciprofloxacin as reference. Determination of minimum inhibitory concentration (MIC) and zone of inhibition showed that the molecules were more active against Gram ?ve bacteria than Gram +ve bacteria. The compounds showed promising antibacterial properties with MIC ranging between 10 and 30 μg/mL.  相似文献   
175.
We explored the potential role of peroxisome proliferator activated receptor‐γ (PPAR‐γ) in stevioside‐mediated renoprotection using rhabdomyolysis‐induced acute kidney injury (AKI) model in rats. Rhabdomyolysis refers to intense skeletal muscle damage, which further causes AKI. Glycerol (50% w/v, 8 ml/kg) was injected intramuscularly in rats to induce rhabdomyolysis. After 24 hr, AKI was demonstrated by quantifying serum creatinine, urea, creatinine clearance, microproteinuria, and electrolytes in rats. Further, oxidative stress was measured by assaying thiobarbituric acid reactive substances, generation of superoxide anion, and reduced glutathione levels. Additionally, serum creatine kinase (CK) level was assayed to determine glycerol‐induced muscle damage in rats. Pathological changes in rat kidneys were studied using hematoxylin–eosin and periodic acid Schiff staining. Moreover, the expression of apoptotic markers (Bcl‐2, Bax) in rat kidneys was demonstrated by immunohistochemistry. Stevioside (10, 25, and 50 mg/kg) was administered to rats, prior to the induction of AKI. In a separate group, bisphenol A diglycidyl ether (BADGE, 30 mg/kg), a PPAR‐γ receptor antagonist was given prior to stevioside administration, which was followed by rhabdomyolysis‐induced AKI in rats. The significant alteration in biochemical and histological parameters in rats indicated AKI, which was attenuated by stevioside treatment. Pretreatment with BADGE abrogated stevioside‐mediated renoprotection, which is suggestive of the involvement of PPAR‐γ in its renoprotective effect. In conclusion, stevioside protects against rhabdomyolysis‐induced AKI, which may be attributed to modulation of PPAR‐γ expression.  相似文献   
176.

Objectives

Microscope work can be strenuous both to the visual system and the musculoskeletal system. Lack of awareness or indifference towards health issues may result in microscope users becoming victim to many occupational hazards. Our objective was to understand the occupational problems associated with regular use of microscope, awareness regarding the hazards, attitude and practice of microscope users towards the problems and preventive strategies.

Material and Methods

a questionnaire based survey done on 50 professionals and technicians who used microscope regularly in pathology, microbiology, hematology and cytology laboratories.

Results

Sixty two percent of subjects declared that they were suffering from musculoskeletal problems, most common locations being neck and back. Maximum prevalence of musculoskeletal problems was noted in those using microscope for 11–15 years and for more than 30 h/week. Sixty two percent of subjects were aware of workplace ergonomics. Fifty six percent of microscope users took regular short breaks for stretching exercises and 58% took visual breaks every 15–30 min in between microscope use sessions. As many as 94% subjects reported some form of visual problem. Fourty four percent of microscope users felt stressed with long working hours on microscope.

Conclusions

The most common occupational concerns of microscope users were musculoskeletal problems of neck and back regions, eye fatigue, aggravation of ametropia, headache, stress due to long working hours and anxiety during or after microscope use. There is an immediate need for increasing awareness about the various occupational hazards and their irreversible effects to prevent them.  相似文献   
177.
This study aims to develop amorphous solid dispersion (ASD) of lumefantrine with a cost-effective approach of spray anti-solvent precipitation. Four acidic polymers, hydroxypropylmethylcellulose phthalate (HPMCP), hydroxypropylmethylcellulose acetate succinate (HPMCAS), poly(methacrylic acid–ethyl acrylate) (EL100) and cellulose acetate phthalate (CAP) were studied as excipients at various drug-polymer ratios. Of the studied polymers, satisfactory physical stability was demonstrated for HPMCP- and HPMCAS-based ASDs with no observed powder X-ray diffraction peaks for up to 3 months of storage at 40 °C/75% RH. HPMCP and HPMCAS ASDs also achieved greater drug release levels in the dissolution study than other polymers. The HPMCP-based ASDs with a drug:polymer ratio of 2:8 exhibited a maximum drug release of 140 μg/mL for up to 2 h, which is significantly higher than the currently marketed formulation of Coartem® (<80 ng/mL). Relatively, the CAP and EL100 ASDs indicated a higher water content and crystallized within a day when stored at 40 °C/75% RH. The choice of polymer, and the drug-polymer ratio played a crucial role in the solubility enhancement of lumefantrine. Our study indicates that the developed spray anti-solvent precipitation method could be an affordable approach for producing ASDs.  相似文献   
178.
The present communication reports the dose and duration dependent toxicity of a PCB, Aroclor 1254, to a few ion dependent ATPases, Acid phosphatase, Alkaline phosphatase and Glucose-6-phosphatase in the whole brain tissue of mice. Two groups of mice were subjected to two sublethal doses (0.1 and 1 mg kgbw−1 day−1) of PCB orally and exposed for 4, 8 or12 days. A separate control group received the corn oil vehicle for the same exposure times. The observed results indicated exposure duration dependent changes in the enzymatic levels in the brain. The results suggest that the alteration in the enzymatic activity was possibly due to imposed oxidative stress generated by Aroclor 1254 on membrane-bound ion-dependent ATPases and other phosphatases in the brain tissue.  相似文献   
179.
In the present study, prodrug of ketoprofen was synthesized and evaluated in vitro to optimize the prodrug, and in vivo to observe the reduction in gastrointestinal disturbance and enhanced colonic anti- inflammatory potential for the prodrug. The prodrug was synthesized by coupling ketoprofen with l-glycine (KET-GLY). In vitro reversion of KET-GLY to ketoprofen was carried out in different pHs and in pH 6.8 containing optimized rat fecal material. In vivo healing potential of KET-GLY was evaluated in acetic acid-induced experimental colitis model. In vitro reversion studies suggested that KET-GLY remained intact in stomach but released the free drug at pH 6.8 containing fresh rat fecal material, where the colonic microfloral enzymes (amidase) hydrolyzed the KET-GLY amide linkage, releasing the free drug. In vivo evaluation indicated KET-GLY to be less toxic in stomach, with enhanced anti-inflammatory potential in the colonic region. These findings suggested KET-GLY to be better in action compared with the parent drug.  相似文献   
180.
Staphylococcus epidermidis is reported to be the main causative agent of nosocomial infections. It has become increasingly difficult to treat this micro-organism because of the emergence of new antibiotic-resistant strains and its ability to form biofilm on medical associated devices. Phytochemicals acting in synergy are effective in killing the micro-organisms by lowering the doses, and synergistic compounds evade the development of resistance due to different mechanism of action. This study aims to determine the synergistic antimicrobial potential of curcumin with cinnamaldehyde, eugenol, and ellagic acid against S. epidermidis. Curcumin with ellagic acid as well as eugenol were found to have additive antimicrobial effect, whereas, in combination, curcumin and cinnamaldehyde were found to have synergistic effect against S. epidermidis (fractional inhibitory concentration index (FICI) = 0.5). Synergy between curcumin and cinnamaldehyde was established by time–kill kinetics and was further evaluated for antibiofilm activity. The dose required to inhibit biofilm formation was reduced to half than that needed to inhibit its planktonic culture (minimal inhibitory concentration (MIC) of curcumin = 3.12 μg/ml; MIC of cinnamaldehyde = 15.62 μg/ml; FICI = 0.248). Both curcumin and cinnamaldehyde disrupted the bacterial membrane for killing the bacteria as determined by permeability studies on Escherichia coli ML-35p.  相似文献   
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