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991.
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993.

Introduction

We designed the present study to evaluate the efficacy of melatonin (M) on the severity of necrotizing enterocolitis (NEC) in a neonatal rat model.

Materials and Methods

Immediately after birth, pups were weighed and randomized into 3 groups: NEC, NEC + M, and control. Necrotizing enterocolitis was induced by enteral formula feeding and exposure to hypoxia after cold stress at 4°C and oxygen. The NEC + M group received 10 mg/kg M daily for 3 days after the first day of the NEC procedure. The pups were killed on the fourth day, and their intestinal tissues were harvested for biochemical and histopathologic analysis. Blood samples were also obtained from the pups.

Results

The mortality rate and weight loss were highest in the NEC group. Malondialdehyde and protein carbonyl content were significantly increased, whereas superoxide dismutase and glutathione peroxidase were decreased in the NEC-treated pups. Melatonin prevented these changes, with these values being similar to control levels in the NEC + M group. Nitrate plus nitrite levels and serum tumor necrosis factor α and interleukin-1β were increased in the NEC group, and histopathologic injury score in the NEC group was significantly higher than that in the NEC + M group.

Conclusion

Melatonin significantly reduced the severity of NEC in our study.  相似文献   
994.
The aim of this study was to evaluate the mineral content of dentin prepared using an Er,Cr:YSGG laser at four different power settings, acid etching, and air abrasion. The study teeth comprised 35 molars which were randomly divided into seven equal groups. The occlusal third of the crowns were cut with a slow-speed diamond saw. The groups were as follows: group A, control group; group B, dentin etched with 35% buffered phosphoric acid for 30 s; group C, dentin abraded at 60 psi with 50-μm aluminium oxide for 1 s; groups D–G, dentin irradiated with the Er,Cr:YSGG laser at 1.50 W (group D), 2.25 W (group E), 3.00 W (group F), and 3.50 W (group G). The levels of Mg, P, Ca, K and Na in each dentin slab were measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). Data were analysed by one way analysis of variance and Tukey HSD tests. There were no significant differences between the groups in the levels of Ca, P and Na, and the Ca/P ratio (p>0.05); however, there were significant differences in the levels of K (p<0.001) and Mg (p=0.13). In addition, the levels of Mg in the air abrasion group were higher than in the other groups (p<0.01). Etching with the Er,Cr:YSGG laser system, air abrasion and acid etching did not affect the levels of Ca, P and Na, or the Ca/P ratio, in the dentin surface.  相似文献   
995.
Shock Wave Lithotripsy (SWL) has become the preferred first-line approach to most patients with symptomatic urolithiasis. The purpose of this study is to assess the ideal patient position during SWL for the treatment of distal ureter stones. A total of 342 patients included in this retrospective study. 148 (108 men, 40 women) patients were included in the first group and were treated in supine position. The remaining 194 (143 men, 51 women) patients were included to second group and were treated in prone position. This study designed retrospectively. The procedure was accepted as a success if the patient was stone free or had only clinically insignificant fragments (≤3 mm) for 3 months or more after the last SWL session. Before SWL, the mean is one area in the first group was 61.32 mm2 while the mean stone area in the second group was 59.04 mm2 (p = 0.208). Mean energy, Mean energy maximum and mean number of applied shock waves of the first group was 4.65, 3.19 and 3,960, respectively. The same parameters in second group were 4.26, 3.03 and 2,953, respectively. These results show that there are statistically significant differences between two groups with respect to mean energy, mean energy maximum and mean number of applied shock waves (p = 0.003, p = 0.010, p = 0.000, respectively). Success rate was 85.1% in group 1 and 72.7% in group 2 (p = 0.006). Our results suggest that supine position is effective and better than prone position for SWL in patients with distal ureteric stones.  相似文献   
996.

Background:

Although various techniques have been described for correction of crooked and saddle nose deformities, these problems are challenging with high recurrence and revision rates. Conventional septal surgery may not be adequate for nose reconstruction in crooked and saddle nose deformities.

Materials and Methods:

Between December 2005 and October 2009, six patients with crooked nose and five patients with saddle nose deformities underwent corrective surgery in our clinic. All patients were male, and the mean age was 21 years (range, 19-23 years). We used rigid radial bone graft to prevent redeviation and recurrence following corrective nasal septal surgery.

Results:

The mean follow-up period was 28 months, ranging from 18 to 46 months. Mean operation time was 4 hours (3-4.5). All patients healed uneventfully. None of the patients required secondary surgery.

Conclusions:

We believe that radial bone grafts offer a long lasting support in treatment of challenging cases with crooked and saddle nose deformities.  相似文献   
997.
998.
Aim This study examined the indications for a stoma in patients with Fournier’s gangrene and its impact on outcome. Method Patients with Fournier’s gangrene were retrospectively reviewed for indications for a stoma. Patients with and without a stoma were compared, based on demographics, disease severity, surgical therapy, length of hospital stay, clinical outcome and cost. Results Forty‐four patients (median age 57 years, range 28–77 years) were evaluated. Eighteen had a temporary stoma and 26 did not. A stoma was 5 times more likely in males. Patients with Fournier’s gangrene originating from an anorectal disorder received a stoma more often than patients with disease originating from an urogenital disorder. Clinical outcomes were similar for patients with or without a stoma. Stoma closure was associated with an extra cost of about $6650 per patient. Conclusion Stoma creation in the management of Fournier’s gangrene was needed for selected patients. Having a stoma did not appear to affect outcomes and resulted in a significant increase in cost of care.  相似文献   
999.

Background

Gonadotropins, as ovulation-inducing drugs, have been used widely to treat infertility. An epidemiologic correlation between infertility therapy and ovarian cancer development has been reported. However, the effect of gonadotropins in the formation of reproductive tract cancers is controversial.

Objective

The aim of the study was to determine the in vivo genotoxic effects of gonadotropins on rat reticulocytes.

Methods

In this prospective, randomized, controlled study, rats were randomly assigned to 1 of 5 groups. The calculated rat doses of 0.65 human menopausal gonadotropin (hMG), 0.95 hMG, 0.65 follitropin beta (FB), 0.95 FB, or normal saline (control group) were injected, respectively. These calculated rat doses (U/g) are based on average human gonadotropin doses of 150 and 225 IU/d for a 70-kg woman given in 2-mL saline (the control group received 2 mL of saline). Injections were administered once per day for 5 days, followed by 5 days of rest. Each treatment was repeated for 6 estrus cycles in the rats for a total of 12 estrus cycles. Six months after the last day of the 12th cycle, the rats were euthanized. Bone marrow tissues were removed, and pluripotent reticulocyte cells with micronuclei, nuclear buds, and binuclear abnormalities were analyzed using an in situ micronuclei assay under light microscopy. The proportion of micronucleated cells, cells with anaphase bridge, nuclear buds, and other nuclear abnormalities were measured.

Results

The number of cells with nuclear buds and binuclear abnormalities in the hMG 225 and FB 225 groups was significantly higher (P < 0.05) than that from the hMG 150, FB 150, and control groups in the cytogenetic analysis of bone marrow stem cells. An increased rate of genotoxicity in all gonadotropin groups versus that of placebo was found.

Conclusion

In rats, the micronucleus genotoxicity assay suggests a dose-dependent gonadotropin effect on genomic instability in bone marrow stem cells in vivo.  相似文献   
1000.
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