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91.
92.
The aim of this study was to investigate the effects of aging on the central nervous system steroid and myelin basic protein (MBP) profiles. Forty-seven male Sprague-Dawley rats (newborn, 1, 6, 12 and 24-monthsold) were studied. Tissues were obtained from the cerebellum and parietal, frontal, temporal cortex of the central nervous system of the rats for steroid extraction. The estradiol, progesteron, testosterone and dehydroepiandrosterone (DHEA) levels were measured by Enzyme Linked Immunosorbent Assay (ELISA). The average levels of estradiol (pg/g), progesteron (ng/g), DHEA (ng/g) and testosterone (ng/g) in the brain tissues were respectively 24.29, 4.59, 0.27, 0.92 in the newborn-rats; 4.18 ± 1.10, 1.54 ± 0.30, 0.28 ± 0.01, 0.57 ± 0.10 in the 1 month-old-rats; 11.02 ± 1.10, 2.96 ± 0.30, 0.27 ± 0.01, 0.61 ± 0.10 in the 6 month-old-rats; 15.80 ± 1.10, 4.80 ± 0.30, 0.28 ± 0.10, 0.67 ± 0.10 in the 12 monthold- rats; 20.07 ± 1.10, 4.12 ± 0.30, 0.28 ± 0.01, 0.55±0.10 in the 24 month-old-rats. The myelin basic protein levels were determined by immunohistochemical staining and an elevation was observed in conjunction with the aging process. The results of the study indicate that the alterations in MBP, DHEA, progesterone, testosterone and estrodiol concentrations in the central nervous system of the rats during aging can be considered fundamental for future animal and human studies.  相似文献   
93.
Zn–Al layered double hydroxides (LDHs) were synthesized by a chemical method, while polyvinyl alcohol (PVA) nanofibers were fabricated by an electrospinning approach; we also synthesized Zn–Al LDH/cefotaxime (cefotax), Zn–Al LDH@PVA, and Zn–Al LDH/cefotax@PVA (LCP). Characterizations were performed by X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectroscopy, Brunauer–Emmett–Teller analysis, thermogravimetric-differential thermal analysis techniques, dynamic light scattering, X ray-florescence, and carbon, hydrogen, and nitrogen (CHN) analyses. The adsorption isotherm of cefotax and its entrapment percentage, release, and kinetics were also investigated. The results confirmed the elemental constituents of the mentioned formulas, which exhibited different degrees of crystallinity and different morphologies. Besides, these formulas were tested in vitro as antimicrobial agents and applied in vivo against second-degree wound burns induced in rats'' skin. The adsorption of cefotax occurred chemically, and the experimental data were fitted with different isotherm models, where the Freundlich and Toth models gave the best fits. The entrapment percentage in LDH/cefotax was 77.41% and in LDH/cefotax@PVA, it was 67.83%. The sustained release of cefotax from LDH and LCP was attainable; the release percentages were 89.31% and 81.55% in up to 12 h, respectively. The release kinetics of cefotax from LDH fitted well with first-order kinetics, while that for LCP was parabolic. The formulas showed uneven antimicrobial effects against Gram-positive and Gram-negative bacteria; the best effect was exhibited by Zn–Al LDH/cefotax@PVA due to its sustained release. Finally, investigating the possibility of using these formulas in the clinical setting should be considered.

This study succeeded to formulate, characterize, and investigate cefotax release and kinetics, and to compare cetofax with other known antibacterial agents.  相似文献   
94.
Posttraumatic spondyloptosis develops as a result of complete subluxation of the vertebral bodies and causes complete transection of the spinal cord. Severe trauma-related spondyloptosis of the upper-mid thoracic region is a rare form of spinal trauma. Traumatic midthoracic spondyloptosis is quite rare, and radiology plays an important role in the diagnosis and treatment of this condition. Surgical reconstruction and stabilization are required for early mobilization and rehabilitation of patients with this injury. Here, we report the clinical features, radiographic findings, and management of an unusual case of traumatic midthoracic spondyloptosis that showed complete spinal cord transection and was operated.  相似文献   
95.
We investigated the possible use of D -lactate as a predictor in the diagnosis of appendicitis. C-reactive protein level (CRP) and leukocyte counts were also evaluated. Venous blood D -lactate, CRP, and leukocyte counts were measured preoperatively in 53 patients undergoing surgery for appendicitis, as well as in 20 healthy subjects. Levels of all three parameters in the surgical patients were significantly higher than in the control group ( p < .05). Previous studies have shown that venous D -lactate is more specific to the intestine than CPR or leukocyte count. Based on our data, venous D -lactate, which had the lowest false-negative rate among these laboratory parameters, may be a useful diagnostic marker for appendicitis. None of these parameters were helpful in identifying the type of the appendicitis.  相似文献   
96.
Objective: We examined the cardioprotective effects of propofol and ketamine with and without N-acetylcysteine (NAC). Methods: 60 rats were divided into six groups of 10 rats each. Anesthesia induction was produced with an intraperitonal injection of ketamine in Groups 1–3 and propofol in Groups 4–6. NAC (200 mg kg? 1) was given intraperitonally during anesthesia induction in Groups 3 and 6. Groups 2, 3, 5, and 6 were subjected to 90 s of myocardial ischemia by clamping the ascending aorta, and then reperfusion was begun by unclamping the ascending aorta. After 60 min of reperfusion, blood samples were taken from the ascending aorta for biochemical analyses, and heart tissue samples were taken for biochemical and histopathological analyses. Results: Creatine kinase (CK), myocardial band of creatine kinase (CK-MB), and troponin-I (Tn-I) levels were significantly higher in the ischemia–reperfusion groups (2, 3, 5, 6) compared to the nonischemic groups (1, 4). CK, CK-MB, and Tn-I levels did not differ significantly between the ketamine groups (1–3) and the propofol groups (4–6) p >. 05). Malondialdehyde levels were significantly higher in Groups 2 and 3 than in Group 1 and were significantly lower in Groups 4 and 6 than in Group 5 (p <. 05). Malondialdehyde levels in the propofol groups (4–6) were significantly lower than in the ketamine groups (1–3; p <. 05). Catalase levels in propofol groups were higher than ketamine groups. Superoxide dismutase levels were significantly higher in Group 6 than in Group 3 (p <. 05). Conclusions: In this rat model of global cardiac ischemia, propofol with NAC attenuates myocardial injury more than ketamine (with or without NAC).  相似文献   
97.
ABSTRACT

Purpose/Aim: Acute mesenteric ischemia is a syndrome characterized by sudden onset abdominal pain followed by intestinal necrosis. Morbidity and mortality increase with delayed diagnosis. Even with the latest radiological diagnostic methods, early diagnosis and initiation of treatment can be delayed. Using an experimental model, here we aim to determine the relationship between the laboratory parameters used to detect acute mesenteric ischemia and the duration of irreversible ischemia. Materials and Methods: A total of 30 male Wistar albino rats were divided into five groups, all of which underwent general anesthesia: (i) Superior mesenteric artery (SMA) dissection with laparotomy was performed, and blood samples and intestinal segment samples were taken after 2 hr (Sham group); (ii) volvulus of one-third of the small intestines was performed manually by laparotomy, and blood samples and intestinal segment samples were taken after 2 hr (Volvulus group); (iii) SMA was ligated with laparotomy, and blood samples and intestinal segment samples were taken after 2 hr (SMA+ligated 2-hr group); (iv) SMA was ligated with laparotomy, and blood samples and intestinal segment samples were taken after 4 hr (SMA+ligated 4-hr group); and (v) SMA was ligated with laparotomy, and blood samples and intestinal segment samples were taken after 6 hr (SMA+ligated 6-hr group). Results: The mean lactate dehydrogenase (LDH) activities of the SMA+ligated 2-hr and SMA+ligated 6-hr groups were statistically higher than the control group (p = .004). Compared to the Sham and Volvulus groups, the mean lactate level of the SMA+ligated 6-hr group was significantly higher (p = .004). Compared to the Sham and Volvulus groups, the mean D-dimer levels of the SMA+ligated 4-hr and SMA+ligated 6-hr groups were significantly higher (p = .004 and .003, respectively). By histopathological evaluation, we found that pathological damage increased as the ischemia lengthened. Conclusions: Mesenteric ischemia leads to an irreversible loss of intestinal perfusion and an increase in parameters of ischemia. Irreversible tissue damage occurs after 4 hr of ischemia and peaks after 6 hr, whereas parameters of ischemia (D-dimer, LDH, and L-Lactate levels) are highest at 2 hr after the onset of ischemia.  相似文献   
98.
Vascular access thrombosis is a leading cause of vascular access failure in hemodialysis patients. Thrombosis is a multifactorial condition and genetic makeup can affect thrombosis risk. We conducted a study to investigate for possible associations between ecNOS gene intron 4 variable-number tandem repeat (VNTR) polymorphism and thrombosis of polytetrafluoroethylene hemodialysis arteriovenous access grafts (AVG) in Turkish patients. Fifty-five patients with end-stage renal disease who had AVGs implanted between 2000 and 2002 and 167 healthy individuals representing our healthy population were enrolled in this prospective study. Each subject provided a venous blood sample from which DNA was isolated, and polymerase chain reaction analysis was done to identify genotypes (aa, bb, ab) for ecNOS gene intron 4 VNTR polymorphism. All grafts were placed in brachioaxillary position. The subjects were divided into two groups based on duration of graft patency. The thrombosis group (Group I) comprised 26 patients who developed AVG thrombosis in the first 12 months after placement. The no-thrombosis group (Group II) comprised 29 patients whose grafts remained patient for at least 12 months. The frequency of the aa genotype in Group I was significantly higher than that in Group II (p =. 005). At 6, 12, and 24 months, the primary patency rates for the AVGs in patients with the aa genotype were significantly lower than the corresponding rates for the bb and ab genotype groupings (p =. 01, p =. 01 and p =. 04 for the three respective time points; Kaplan–Meier). ecNOS gene intron 4 VNTR polymorphism is linked with the pathogenesis of vascular access thrombosis in Turkish patients undergoing hemodialysis.  相似文献   
99.
The use of mesh has become the gold standard in hernia operations recently due to advantages such as lower recurrence rates, lower post-surgical pain and earlier return to work. Plug mesh application, first described by Robins and Rutkow [Robbins AW, Rutkow IM (1993) The mesh-plug hernioplasty. Surg Clin North Am 73:501–512], is a popular method of hernia repair. Although rare, there may be complications of surgery using plug mesh. This report presents a case of mechanic bowel obstruction due to mesh migration, 3 years after a left inguinal hernia repair with plug mesh method.  相似文献   
100.
The aim of this study was to develop a novel nanosize drug candidate for cancer therapy. For this purpose, (S)-methyl 2-[(7-hydroxy-2-oxo-4-phenyl-2H-chromen-8-yl)methyleneamino]-3-(1H-indol-3-yl)propanoate (ND3) was synthesized by the condensation reaction of 8-formyl-7-hydroxy-4-phenylcoumarin with l -tryptophan methyl ester. Its controlled release formulation was prepared and characterized by different spectroscopic and imaging methods. The cytotoxic effects of ND3 and its controlled release formulation were evaluated against MCF-7 and A549 cancer cell lines, and it was found that both of them have a toxic effect on cancer cells. For drug design and process development, the molecular docking analysis technique helps to clarify the effects of some DNA-targeted anticancer drugs to determine the interaction mechanisms of these drugs on DNA in a shorter time and at a lower cost. By using the molecular docking analysis and DNA binding assays, the interaction between the synthesized compound and DNA was elucidated and non-binding interactions were also determined. To predict the pharmacokinetics, and thereby accelerate drug discovery, the absorption, distribution, metabolism, excretion and toxicity values of the synthesized compound were determined by in silico methods.  相似文献   
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