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991.
Risk Factors and Management of Bile Leakage after Hepatic Resection   总被引:12,自引:0,他引:12  
The aim of this study was to identify the perioperative risk factors for postoperative bile leakage after hepatic resection and to propose a treatment strategy for such leakage when it does occur. Between 1992 and 2000 a total of 313 hepatic resections without choledocojejunal anastomosis were performed at our institute. Risk factors related to bile leakage were identified with univariate analysis, and strategies were evaluated in relation to the findings of postoperative fistulography. Postoperative bile leakage developed in 17 patients (5.4%). Univariate analysis identified high risk factors as advanced age, a wide surface area of the incision (bile leakage group versus no bile leakage group: 102.1 vs. 66.4 cm2, p < 0.05), and exposure of Glissons sheath at the cut surface (e.g., central bisegmentectomy, S4, S8 subsegmentectomy). Groupings of patients by their postoperative fistulography results showed that patients with involvement of the proximal bile duct were slower to heal than those with no demonstrable bile duct involvement. The one patient whose fistulogram demonstrated peripheral bile duct involvement had uncontrollable leakage and required reoperation. Hepatectomies with a wide surface area and those that expose the major Glissons sheath present serious risk factors for bile leakage. When the fistulogram shows proximal bile duct involvement, endoscopic nasobiliary tube drainage is necessary; when the fistulogram shows peripheral bile duct involvement, reoperation is needed.  相似文献   
992.
Yoshimura J  Onda K  Tanaka R  Takahashi H 《Neurologia medico-chirurgica》2003,43(8):375-82; discussion 382
Diffuse type brainstem glioma is one of the most malignant types of brain tumors and the prognosis is extremely poor. The proliferative potential of these tumors is presumed to be very high, but there is little information about the cell kinetics of brainstem glioma because surgical resection is rarely performed. The histological grade, tumor spread, growth potential, and prognosis were evaluated in 40 autopsy cases of diffuse type brainstem glioma. To quantify the growth potentials of individual tumors, the proliferating cell indices of Ki-67 (MIB-1) and proliferating cell nuclear antigen (PCNA) monoclonal antibodies were measured. Mean MIB-1 and PCNA proliferating cell indices were 20.4% (24 cases) and 37.0% (28 cases), respectively, in 34 glioblastomas. The median survival time was 40 weeks in 22 treated patients. The mean PCNA proliferating cell index was 10.8% in four of five anaplastic astrocytomas and the median survival time in four treated patients was 91 weeks. The MIB-1 and PCNA proliferating cell indices of one astrocytoma were 2.9% and 20.3%, respectively, and the survival time was 56 weeks. The overall median survival time was 32 weeks. There was a significant difference in PCNA proliferating cell indices between glioblastomas and anaplastic astrocytomas (p < 0.05) and there was a significant difference in survival time between glioblastomas (40 weeks) and anaplastic astrocytomas plus astrocytoma (74 weeks) among the treated patients (p < 0.05). Supratentorial extension was more frequent in glioblastomas than in anaplastic astrocytomas (p < 0.05). Our results suggest that the majority of diffuse type brainstem gliomas are glioblastoma and the proliferative potential is probably as high as that of adult supratentorial glioblastoma. Supratentorial extension and dissemination are relatively frequent in the advanced stage. Anaplastic astrocytoma or astrocytoma is rarer and less infiltrative and proliferative, and carries a slightly better prognosis than glioblastoma.  相似文献   
993.
A 39-year-old man presented with multiple intracranial cavernous malformations manifesting as intractable seizures persisting for more than 20 years. He underwent gamma knife radiosurgery (GKRS) for right frontal and left temporal cavernous malformations. He began to suffer from progressive left hemiparesis and inattention 2 years 5 months after the GKRS. Magnetic resonance imaging showed abnormal ring enhancement and extensive brain edema around the right frontal lesion. Conservative therapies such as external decompression, low-dose barbiturates, and mild hypothermia had no effect on his clinical status. Stereotactic biopsy of the ring-enhanced area demonstrated gliosis. Signs of cerebral herniation appeared, so we performed partial resection of the right frontal lobe. His symptoms recovered immediately. Subsequent hyperbaric oxygen (HBO) therapy significantly improved the extensive brain edema. Delayed radiation necrosis associated with potentially fatal brain edema may occur after GKRS for cavernous malformations. Internal decompression and subsequent HBO therapy were very effective for the treatment of these lesions.  相似文献   
994.
A 50-year-old man presented with subarachnoid hemorrhage from a ruptured cerebral aneurysm arising from a left posterior inferior cerebellar artery (PICA)-anterior inferior cerebellar artery anastomotic artery manifesting as severe headache, obtundation, and quadriplegia. Conventional and three-dimensional digital subtraction angiography showed that the anastomotic complex was present bilaterally and both vertebral arteries terminated at the origin of the PICA. The identification of this anomalous vascular network allowed coil embolization of the broad-based aneurysm with occlusion of the parent artery. The patient had residual moderate disturbance of consciousness and quadriplegia before transfer for rehabilitation.  相似文献   
995.
Duchenne muscular dystrophy is known to be caused by a defective gene of dystrophin, a 427-kDa cytoskeletal protein, but the effective therapeutic drug is presently unavailable. We previously reported that a trypsin-like protease designated as dystrypsin is markedly activated in the muscle microsomal fraction immediately before onset of the clinical signs in mdx mice, a dystrophin-deficient hereditary animal model for human Duchenne muscular dystrophy. In order to examine the possible participation of dystrypsin in the occurrence of the disease, we investigated the therapeutic effects of dystrypsin inhibitors on the occurrence and progress of muscular dystrophy. Here, we show that camostat mesilate, a low-molecular-weight inhibitor of trypsin-like proteases, including dystrypsin, is a candidate drug for Duchenne muscular dystrophy.  相似文献   
996.
The effects of five levels of population density on various organs, the neuroendocrine system, skin function, skin blood perfusion, and blood parameters were studied in the hairless mouse. Skin barrier recovery was evaluated by measuring transepidermal water loss after tape stripping. Blood perfusion was measured by means of a laser Doppler imaging technique. The effect of a parasympathetic nerve stimulator, carpronium chloride, on skin function in the crowded animal model was also examined. A 7 d crowding (10, 15, 20 mice/cage) significantly increased the levels of corticosterone, catecholamines (norepinephrine, epinephrine and dopamine), glucose and serum lactate dehydrogenase activity in circulating blood, induced atrophy of kidney, ovary and thymus and hypertrophy of adrenal glands, and decreased body weight gain in comparison with the control (5 mice/cage). Crowding also increased epidermal thickness and epidermal proliferative activity, and decreased corneocyte size, rate of barrier recovery and skin blood perfusion. Most of these changes became more marked with increasing population density and/or longer exposure to a crowded environment. Isolation (1 mouse/cage) increased the level of norepinephrine and rate of skin blood perfusion, and significantly delayed barrier recovery. Repeated topical applications of carpronium chloride for 7 d improved the changes in skin blood perfusion, barrier recovery, kidney and ovary, and epidermal morphology induced by crowding. The crowded animal model could be useful for quantifying objectively the influence of crowded environment-induced stress on cutaneous function and blood perfusion.  相似文献   
997.
We have examined the influence of liver disease on drug absorption from the liver surface membrane, regarded as the first barrier for drug targeting to the liver. The main purpose of this study is to examine the possibility of direct liver surface application as a drug targeting method. We employed rats intoxicated with carbon tetrachloride (CCl(4)) or D-galactosamine (GAL) as the liver disease model, and examined drug absorption characteristics after application to the liver surface, by utilizing a cylindrical diffusion cell. In the liver-intoxicated rats, about 90% of a low molecular weight drug, phenolsulfonphthalein (PSP), as a model was absorbed from the liver surface in 6 h, similar to the normal rats (no treatment). Although the absorption rate was increased in the CCl(4) group, whereas slightly retarded absorption was observed in GAL group, there should be no serious problem for the clinical use of liver surface application. The PSP absorption from the liver surface in the CCl(4) group was indicated to obey first-order kinetics by elimination profile from the diffusion cell. The first-order absorption rate constant K(a) values of PSP from the liver surface, obtained by a compartment model and elimination profile, were increased 1.3-fold in the CCl(4) group compared to the control. Moreover, we performed drug application to the liver surface in the peritoneal cavity to assume clinical use. The K(a) of PSP in the CCl(4) group was about 4-fold larger than in the normal group, implying the importance of estimating changes in peritoneal drug absorption as a result of liver disease. Consequently, it is expected that there will be no marked decline in the absorption rate from the liver surface in a liver disease state, leading us to apply this administration method for liver targeting.  相似文献   
998.
The repeated administration of methamphetamine (MAP) causes behavioral sensitization in animals. We previously reported that the high accumulation of MAP was observed in the MAP-sensitized animal brain, which suggested that this phenomenon is an important factor in the development or expression of behavioral sensitization. The purpose of the present study is to elucidate the MAP distribution in the MAP-sensitized rat using gas chromatography/mass spectrometry (GC/MS). As a result, the MAP distribution in the heart at 10 min when showing a high accumulation of MAP in the MAP-sensitized rat brain was significantly higher than that of the control rat, whereas no significant differences in the liver, kidney, abdominal muscle, femoral muscle and blood were observed. In the brain and heart, there was no different distribution at 1 min, reflecting only the influx process from blood to brain and heart. On the contrary, there was the significant difference at 10 min, reflecting both the influx and efflux process, suggesting that the efflux process of MAP from brain or heart to blood may be slow due to MAP sensitization. In conclusion, it was clear that the brain and heart specific alteration of the MAP distribution occurred in the MAP sensitization. It was considered that the high accumulation of MAP in the MAP-sensitized rat brain may be related to the expression of behavioral sensitization and that the delayed efflux of MAP in the MAP-sensitized rat heart may be connected with the cardiac toxicity.  相似文献   
999.
The enzyme activities of CYP2D6 and CYP2C19 show a genetic polymorphism, and the frequency of poor metabolizers (PMs) on these enzymes depends on races. In the present study, the frequencies of mutant alleles and PMs in each race were analyzed based on information from published studies, considering the genetic polymorphisms of CYP2D6 and CYP2C19 as the causal factors of racial and inter-individual differences in pharmacokinetics. As a result, it was shown that there were racial differences in the frequencies of each mutant allele and PMs. The frequencies of PMs on CYP2D6 are 1.9% of Asians and 7.7% of Caucasians, and those of PMs on CYP2C19 are 15.8% of Asians and 2.2% of Caucasians. Based on the results, it was suggested that there would be racial differences in the frequencies of PM subjects whose blood concentrations might be higher for drugs metabolized by these enzymes. Additionally, it was suggested that enzyme activities would vary according to the number of functional alleles even in subjects judged to be extensive metabolizers (EMs). In the bridging study, genetic information regarding CYP2D6 and CYP2C19 of the subjects will help extrapolate foreign clinical data to a domestic population.  相似文献   
1000.
PURPOSE: To report on a simple method to obtain a better view of corneal opacities during excimer laser phototherapeutic keratectomy (PTK). DESIGN: An interventional case report. METHODS: Phototherapeutic keratectomy was performed under sclerotic scattering illumination with a vitrectomy-endoilluminator at the limbus. RESULTS: During conventional PTK with diffuse illumination, the intraoperative observations of corneal opacities are not as good as that with a slit lamp. Conversely, subtle corneal opacities can be easily seen with sclerotic scattering illumination even under a surgical microscope. CONCLUSIONS: The use of sclerotic scattering illumination during PTK is valuable, because it provides a better view of opacified tissues and avoids excessive ablation.  相似文献   
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