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101.
Stature estimation based on hand length and foot length   总被引:1,自引:0,他引:1  
This study was carried out to estimate the relationship between hand length, foot length and stature using multiple linear regression analyses based on a sample of male and female adult Turks residing in Adana. Measurements of hand length, foot length and stature were taken from 155 adult Turks (80 male, 75 female) aged 17-23 years. The participants were students of the Medical Faculty of Cukurova University. A multiple linear regression model was fitted to the observed data. Stature was taken as the response or dependent variable, hand length and foot length were taken as explanatory variables or regressors. All possible (simple and multiple) linear regression models for each of males, females and both genders together were tested for the best model. The multiple linear regression model for both genders together was found to be the best model with the highest values for the coefficients of determination R2 = 0.861 and R2adjusted = 0.859, and multiple correlation coefficient R = 0.928.  相似文献   
102.
An ideal gene carrier is required both in safety and efficiency for transfection. We examined the use of water soluble chitosan and polyethyleneimine as a carrier for anti-angiogenic protein, TSP-1 coded, in gene delivery. The aim of this study was to synthesize and characterize polyethylene glycol conjugated cationic polymers to increase anti-angiogenic gene transfection and reduce possible cytotoxicity. Gel electrophoresis study showed strong DNA binding ability of modified cationic polymers. Also structural properties of pegylated polymers were confirmed by (1)H-NMR. We investigated in vitro properties of PEG conjugated and coated particles which were observed between 145 and 250 nm with the positive zeta potential value. In addition, the chitosan-based DNA complexes did not induce remarkable cytotoxicity against MCF-7 cells. Due to low cytotoxicity, we observed high transfection efficiency at chitosan-based formulations compared with PEI ones. Although transfection studies carried on in vitro conditions, we measured slight increases at transfection with PEGylation. PEG-conjugated chitosan formulations can be a promising candidate due to its efficiency in condensing and transfection of pDNA, its low cytotoxicty and comparatively high encapsulation degree.  相似文献   
103.

Purpose

Endometrial biopsy preceding implantation in in vitro fertilization (IVF) treatment causes a type of injury which facilitates implantation. Pre-treatment hysteroscopic evaluation of uterine cavity also raises the success in IVF. This study investigates whether office hysteroscopy and concurrent endometrial biopsy performed in the luteal phase, on the day of GnRH agonist initiation for long protocol, improves subsequent IVF outcome.

Methods

A prospective, nonrandomized, controlled study of 128 normoresponder women was performed: In 70 women (study group), office hysteroscopy and concurrent endometrial biopsy were performed on the day of GnRH agonist initiation preceding ET cycle and in 58 women (control group), GnRH agonist was initiated without any intervention. However, uterine cavity was shown to be normal with hysteroscopy within the previous 6 months in those women. Implantation and pregnancy rates were compared between the groups.

Results

Intrauterine pathologies were observed in 28 % of women in the study group. Implantation rate (38 vs. 25 %; p = 0.04) and pregnancy rate per ET (67 vs. 45 %; p = 0.01) were found to be significantly higher in the study group compared to the control group.

Conclusion

Office hysteroscopy and concurrent endometrial biopsy performed in the luteal phase, on the day of GnRH agonist initiation for long protocol, provide direct evaluation of the uterine cavity immediately before ET cycle and also significantly improve the implantation and IVF outcome.  相似文献   
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Spinal cord injury (SCI) induced oxidative stress affects multiple organ systems including the kidney. We studied the possible protective effects of melatonin on SCI-induced oxidative damage in renal tissues of rats. Wistar albino rats (n = 24) were exposed to SCI and divided into vehicle- or melatonin-treated SCI groups. Melatonin was administred intraperitoneally at a dose of 10 mg/kg for seven days. Renal tissues were investigated by light and electron microscopy. Furthermore, tissue malondialdehyde (MDA) and glutathione (GSH) levels and myeloperoxidase (MPO) and superoxide dismutase (SOD) activities were also determined. In the vehicle-treated SCI group, the renal histology was disturbed compared to controls, whereas the melatonin-treated SCI group showed significantly reduced degeneration of renal tissue as seen by both light and electron microscopy. MDA levels, MPO and SOD activities were increased and GSH levels were decreased in the vehicle-treated SCI group compared to controls. On the other hand, decreased MDA levels and MPO activities and increased GSH levels were observed in the melatonin-treated SCI group compared to vehicle-treated SCI group. These results showed that experimentally induced SCI caused oxidative stress in the rat kidney, whereas melatonin treatment reduced oxidative stress, suggesting that it may be used as a complementary therapy of renal problems occurring following SCI.  相似文献   
106.
Bottom-up assembly of osteon-like structures into large tissue constructs represents a promising and practical strategy toward the formation of hierarchical cortical bone. Here, a unique two-step approach, i.e., the combination of electrospinning and twin screw extrusion (TSE) techniques was used to fabricate a microfilament/nanofiber shell–core scaffold that could precisely control the spatial distribution of different types of cells to form vascularized osteon-like structures. The scaffold contained a helical outer shell consisting of porous microfilament coils of polycaprolactone (PCL) and biphasic calcium phosphates (BCP) that wound around a hollow electrospun PCL nanofibrous tube (the core). The porous helical shell supported the formation of bone-like tissues, while the luminal surface of nanofibrous core enabled endothelialization to mimic the function of Haversian canal. Culture of mouse pre-osteoblasts (POBs, MC 3T3-E1) onto the coil shells revealed that coils with pitch sizes greater than 135 μm, in the presence of BCP, favored the proliferation and osteogenic differentiation of POBs. The luminal surface of PCL nanofibrous core supported the adhesion and spreading of mouse endothelial cells (ECs, MS-1) to form a continuous endothelial lining with the function similar to blood vessels. Taken together, the shell–core bi-layered scaffolds with porous, coil-like shell and nanofibrous tubular cores represent a new scaffolding technology base for the creation of osteon analogs.  相似文献   
107.
Journal of Digital Imaging - In our pediatric radiology department, radiographs (XR) are the shared responsibility of the body section and interpreted in addition to modality or site-specific...  相似文献   
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Although there is a controversy about success and failure of autologous fat tissue transfers, it is a widely accepted method for soft tissue augmentation and is performed by many plastic surgeons as well as dermatologists all around the world. Its advantages are that it does not cause reactions, its absorption rates have been reduced by increased knowledge, experience, and techniques, it can yield good, long-term results, and there are now preservation techniques that allow reinjections when necessary. However, no single ideal technique has been determined. In this paper a new, simple, T-shaped adaptor for easy, quick, and efficient fat harvesting during liposuction is described. This study not only describes the clinical use of the adaptor, but also histologically examines its effects on fat cells under various vacuum pressures (-250 mmHg, -500 mmHg, -700 mmHg). The study shows that the cell structure of fat tissue harvested under medium power (with vacuum pressures of -250 mmHg and -500 mmHg) is not disrupted, while that of tissue harvested with a vacuum pressure of -700 mmHg was traumatized and occasional cell wall fragmentation occurred. In conclusion, it is shown that the T-shaped adaptor allows harvesting of the desired amount of fat tissue without causing trauma to fat cells when it is used with medium-power suction.  相似文献   
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