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71.
Nowadays, the surgical treatment of male-to-female transsexuals is not rare, but few studies have reported on postoperative results. The aim of this study was to determine the role of magnetic resonance imaging (MRI) in the evaluation of the results of sex reassignment surgery (SRS) in male-to-female transsexual patients. Ten such patients (median age 28 years, range 21–47), who had undergone SRS using an inversion of combined penile and scrotal skin flaps for vaginoplasty, were examined with MRI after the operation. Turbo spin-echo T2-weighted and spin-echo T1-weighted images were obtained on sagittal, coronal, and axial planes with a 1.5 T superconducting magnet. The images were acquired on the sagittal, coronal and axial planes, by using TSE T2 weighted and SG T1 weighted images. MRI was performed within 2 weeks after the operation in six patients and after 1 year in the other four. In all cases, the images were obtained with and without an inflatable silicon vaginal tutor. The average neovaginal depth was 7.9 cm (range 6–10 cm). In four patients, MRI showed the presence of cavernosal rests, and in two there were remnants of the corpus spongiosus. In another patient, an abnormal anterior inclination of the neovagina was present. The average distance of the recto-vaginal septum was 4 mm (range 3–6 mm). No major complications were noted. Our study allowed not only a detailed assessment of the pelvic anatomy after genital reconfiguration, but also provided valuable information on possible complications.  相似文献   
72.
Two-unit blood transfusion accounts for one third of blood use in trauma patients. Artificial oxygen carriers have no need for cross-match, allow volume expansion, prolonged storage at 1-38 degrees C, and improve rheology to reverse ischaemia. Haemoglobin-based oxygen carriers can provide a vital alternative given the predicted future shortfall in blood donations.  相似文献   
73.
PURPOSE: To study eye movements in 3D space - saccades, vergence and combined eye movements - in a subject with Manifest Latent Nystagmus (MLN). METHODS: A 13-year-old girl diagnosed with MLN participated in this study. Saccades, pure vergence along the median plane and combined saccade-vergence movements were recorded under both binocular and monocular viewing. Horizontal eye movements from both eyes were recorded simultaneously with a photoelectric device (Bouis Oculometer). RESULTS: The recordings of saccades, vergence or both components of combined movements show that such movements have a staircase trajectory. The consequence of this staircase behavior is that the time for approaching the target is prolonged. The latency of all types of eye movements is extended when the subject is viewing binocularly, while latency values are normal when viewing monocularly; the difference between the viewing conditions is significant for vergence. CONCLUSION: The normal latency values under monocular viewing are attributed to facilitation of eye movement initiation by the increased nystagmus.  相似文献   
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PURPOSE: To compare aqueous humor concentrations of levofloxacin vs ciprofloxacin when used as prophylactic medications before phacoemulsification. DESIGN: Patients (n = 93) were randomly assigned to receive either 0.5% levofloxacin (Quixin) or 0.3% ciprofloxacin (Ciloxan) using one of the following dosing regimens: (A) 1 to 2 drops four times a day for 2 days preoperatively; (B) 5 doses (1 to 2 drops) delivered every 10 minutes in the hour immediately preceding surgery; or (C) the combination of A and B. METHODS: Aqueous samples (0.1 ml) were obtained immediately before surgery, and drug concentrations were measured using high performance liquid chromatography/mass spectrometry. RESULTS: The mean concentration of levofloxacin in the aqueous humor was significantly greater than that of ciprofloxacin in all treatment groups (P <.001): 284.8 vs 67.4 microg/ml (regimen A); 1,135.6 vs 185.6 microg/ml (regimen B); and 1,618.6 vs 241.5 (regimen C). Dosing regimen B delivered significantly more drug to the aqueous humor than regimen A for both levofloxacin (P < or =.001) and ciprofloxacin (P =.004). Dosing regimen C delivered significantly more drug to the aqueous humor than regimen B for levofloxacin (P =.05) but not for ciprofloxacin (P =.384). CONCLUSIONS: Although the concentration of active drug in levofloxacin is approximately 1.7-fold higher than that in ciprofloxacin, the aqueous concentration of levofloxacin after topical administration was four to seven times greater than ciprofloxacin; these differences were statistically significant. With dosing regimens B and C, levofloxacin concentrations in the aqueous humor were above the MIC90 for most common ocular pathogens, including Staphylococcus and Streptococcus species. Ciprofloxacin did not reach such concentrations in any treatment group.  相似文献   
76.
The thymidine kinase (Tk) gene codes for a cytosolic protein involved in the pyrimidine nucleotide salvage pathway. A functional Tk gene is not necessary for cells in culture, and a naturally occurring Tk deficient phenotype has not been described in humans or animal models. In order to determine the biological significance of the Tk gene, we created Tk(-/-) knockout (KO) mice through homologous recombination in mouse embryonic stem cells. Tk KO mice have shortened life spans compared with their wild-type or Tk heterozygous (HET) siblings. All Tk KO mice develop sclerosis of kidney glomeruli and die before one year of age of kidney failure. Among other changes in KO animals, the most consistent is a switch from exclusively mucous secretion to predominantly serous secretion in the sublingual salivary gland. HET parents can produce KO mice at a frequency approaching Mendelian inheritance. Other observations in KO animals include an elevated level of serum thymidine, a significant decrease in the cloning efficiency of splenic lymphocytes, an increase in the frequency of hypoxanthine guanine phosphoribosyl transferase gene mutant lymphocytes, and histological alteration in the lymphoid structure of the spleen. In addition, KO animals sporadically exhibit inflammation of the arteries, which taken together with the lymphocyte and spleen abnormalities, suggest an abnormal immune system. Alterations in Tk KO mice indicate that the pyrimidine nucleotide salvage pathway is indispensable in vivo.  相似文献   
77.
78.
Traditionally, surgical sigmoid diverticular emergencies used to be treated in stages, but more recently there has been a trend towards definitive surgery with immediate resection plus anastomosis under certain conditions. The aim of this study was to define the morbidity and mortality of resection plus anastomosis with on-table antegrade irrigation and of the Hartmann procedure for complicated sigmoid diverticulitis in relation to the type of peritonitis and to the American Society of Anesthesiologists (ASA) grade of the patients. From April 1999 to April 2002, 38 emergency operations for complicated sigmoid diverticulitis were performed at the San Sebastiano Hospital in Caserta. Six patients underwent operations for obstructions and 32 for perforation (19 Hinchley stage III and 13 Hinchley stage IV). Surgical therapy for obstruction consisted in 4 resections plus anastomosis, 1 subtotal colectomy and 1 Hartmann procedure. Surgical therapy for perforation consisted in 14 resections plus anastomosis and 18 Hartmann procedures. There was 1 case (5%) of anastomotic dehiscence out of 19 primary anastomoses versus 2/19 surgical complications (10%) after the Hartmann procedure. The mortality amounted to 1 death out of 38 (2.6%) in a patient treated with the Hartmann procedure. Left-sided colonic obstruction should be treated by resection plus anastomosis or by subtotal colectomy for ASA II-III patients and by Hartmann's procedure for ASA IV-V patients. ASA II-III patients with localised or generalised non-faecal peritonitis should be treated by resection plus anastomosis, while a Hartmann procedure should be the reasonable option for generalised faecal peritonitis and for ASA IV-V patients with localised or generalised non-faecal peritonitis.  相似文献   
79.
80.
S-(1,2-dichlorovinyl)-L-cysteine (DCVC), a metabolite of a common environmental contaminant, trichloroethylene, is a selective proximal tubular nephrotoxicant. The objective of our study was to examine the dose-response relationship of renal injury and repair following DCVC administration. Male Swiss-Webster mice were injected with DCVC [15, 30, or 75 mg/kg ip in distilled water (10 ml/kg)] and the extent of nephrotoxicity and tissue repair was assessed over a 14-day period. The renal injury due to the low and medium doses of DCVC peaked at 36 and 72 h after dosing, respectively, and then regressed over time due to a timely and adequate tissue repair response. At the highest dose tissue repair was inhibited, thereby causing progression of renal injury, which led to acute renal failure and death of the mice. The possibility that compromised tissue repair was a result of the extensive nephrotoxic injury attendant to the high dose of DCVC was investigated via an equinephrotoxicity study in which separate groups of mice received 40 (LD40) and 75 (LD90) mg DCVC/kg, respectively. Bioactivation-based renal proximal tubular injury measured in these two groups over a time course was identical but there was a marked difference in mortality due to an early and robust tissue repair in the first group relative to the second group. These results support the concept that quantitative evaluation of renal tissue repair in parallel with injury is useful in the assessment of the likely toxic outcome associated with exposure to nephrotoxic drugs and toxicants.  相似文献   
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