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91.
Patients with ulcerative colitis (UC) are at increased risk for colorectal carcinoma (CAC). Despite the fact that patients at risk are followed closely by colonoscopy to screen for dysplasia, the prevalence of CAC is still unacceptably high. The aim of this study was to evaluate the prevalence of risk factors for CAC, such as dysplasia, and to determine the relevance of colonoscopic surveillance in the group who went on to develop cancer. A series of 24 patients with UC were diagnosed with CAC. The patients' records were analyzed retrospectively for duration of UC, prevalence of preoperative dysplasia, and other cancer risk factors (CRFs) (e.g., pancolitis, primary sclerosing cholangitis, early onset of UC, and backwash ileitis). The mean age of the patients at the time of cancer diagnosis was 43 years with an average UC duration of 15 years (6 patients had had UC less than 8 years). CAC was identified preoperatively by colonoscopy in 15 of 24 patients, with an additional 7 of 15 showing flat dysplasia. Five of nine patients without preoperatively diagnosed CAC had flat dysplasia. Overall, 19 patients had additional CRFs, most of them with at least two more CRFs. Despite a regular colonoscopic follow-up for most patients with UC, flat dysplasia was missed in 12 patients preoperatively. Therefore we suggest that patient information should also always include surgical options in each case where significant cancer risk factors are found.  相似文献   
92.
Despite the central and peripheral effects of androgens on the nervous system, the local effects of androgens in the corpus cavernosum penis and their importance for erectile function is still unclear. In this study corpus cavernosum biopsies of eight adult potent patients, aged 19–63 years, undergoing penile deviation surgery (group A) and 12 patients undergoing male-to-female transsexual surgery (group B) were immunostained for nuclear androgen and estrogen-alpha receptors. Additionally, primary corpus cavernosum endothelial cell cultures were obtained from six transsexual patients and exposed to testosterone, dihydrotestosterone, estradiol and progesterone likewise for 7 days. Total cell count was performed and cell metabolic activity was measured by a tetrazolium salt-based assay. Androgen and estrogen-alpha receptors were detected in stromal as well as in endothelial cells. Of all cell nuclei, 74.9% (SD 16.4) in group A and 63.5% (SD 17.1) in group B were positively stained for androgen receptors. The respective percentage of estrogen receptors was 11% (SD 9.5) and 21.2% (SD 12.6). An age-dependent difference in receptor distribution was not observed in either group. In the cell culture system only cultures exposed to testosterone and dihydrotestosterone showed a dose-dependent increase of cell metabolic activity compared to the cultures supplemented with estradiol and progesterone. The significant and age-independent high androgen and low estrogen-alpha receptor distribution found in both groups suggests a possible peripheral effect of androgens at the level of the corpus cavernosum penis in adult humans. This is supported by the observed effect of testosterone and dihydrotestosterone on cell count and endothelial cell metabolism in our cell culture system. The role of estrogens remains unclear.  相似文献   
93.
The treatment of keloid and hypertrophic scars remains difficult. Enzymatic digestion of keloid scars has been previously proposed as an effective treatment strategy for reducing the volume of keloid scars. To test this, we administered intra-lesional injections of pure collagenase (between 600 and 4500 units for each scar) into the keloid and hypertrophic scars of seven human volunteers (five keloid and two hypertrophic scars). Five patients (three keloid and two hypertrophic) received more than one injection of collagenase. The treatment resulted in a temporary reduction in scar volume for three of the patients with keloid scars. However, scar volumes for these three patients returned to the same (or greater) levels after 6 months of follow-up. Treatment with collagenase produced no change in scar volume for the two patients with hypertrophic scar. Side effects were numerous and severe including; pain, swelling, blistering, ulceration and ecchymosis at the site of injection. One patient required admission to hospital for 48 h after the first injection. Maximum length of follow-up was 6 months. None of the seven patients completed the study and returned for final follow-up at 2 years. This pilot study suggests that treatment of keloid and hypertrophic scars with intra-lesional injections of collagenase is ineffective.  相似文献   
94.
BACKGROUND: Based on the association between the neutrophil and ventilator-induced lung injury, the authors hypothesized that neutrophil inhibition with fucoidin would be beneficial and stimulation with granulocyte colony-stimulating factor (G-CSF) would be harmful in a rat model of lethal ventilator-induced lung injury. METHODS: Animals (n = 111) were randomly assigned to be pretreated with fucoidin, G-CSF, or placebo (control) before 4 h of low-tidal-volume (10 ml/kg) or high-tidal-volume (40 ml/kg) mechanical ventilation. RESULTS: All low-volume animals survived. With high volumes, compared with controls, fucoidin did not improve survival (3 of 20 control animals and 5 of 20 fucoidin animals died; P = 0.51) but G-CSF significantly worsened it (18 of 22 animals died; P < 0.001). Circulating neutrophils were increased early with G-CSF and late with fucoidin with low and high tidal volumes (P < 0.05 for each treatment and tidal volume). Fucoidin decreased lung neutrophils, but these were only significant with high tidal volumes, whereas G-CSF increased lung neutrophils but only significantly with low tidal volumes (P < or = 0.01 for each). Fucoidin did not alter any cardiopulmonary measure significantly. Compared with control, G-CSF increased airway pressures with high tidal volumes and worsened lung edema and arterial oxygen with both tidal volumes (P < 0.05 for each). CONCLUSIONS: In this model, neutrophil stimulation by G-CSF increased lung dysfunction and with high tidal volumes worsened survival rates. Extrapolated clinically, neutrophil stimulation either by agents such as G-CSF or conditions such as sepsis may aggravate ventilator-induced lung injury.  相似文献   
95.
Lipofibromatous hamartoma is a very rare benign peripheral nerve tumour. It is mostly encountered in the proximal extremities of young adults, involving the median nerve in the majority of cases. We present two patients with macrodactyly and carpal tunnel syndrome caused by lipofibromatous hamartoma of the median nerve and discuss diagnosis and treatment of the disease. A 10-year-old girl with a congenital progressive macrodactyly of her right index finger presented with a slowly growing mass in her right palm and pain and numbness, along with motor and sensory deficits in the median nerve distribution. Treatment consisted of carpal tunnel release, epineurolysis and partial excision of the fibrofatty tissue. The second patient, a 25-year-old man presented with a swelling in his left palm and findings compatible with carpal tunnel syndrome. Intraoperatively, the lesion presented as sausage-shaped enlargement of the median nerve by fibrofatty tissue. After carpal tunnel release, a partial excision of the mass with epineurolysis was performed. In both patients, histology showed nerve bundles separated by abundant fibrofatty tissue. In the girl, a proliferation of dysplastic perineurial cells could be observed. The suspected diagnosis for patients with macrodactyly and clinical signs of carpal tunnel syndrome should be lipofibromatous hamartoma. A carefully taken history, physical examination, X-ray, and MRI are important for its correct diagnosis. The surgical management remains controversial. Treatment should include decompression of the median nerve at points of compression, partial excision of the fibrofatty tissue, and debulking of soft tissue. In some cases, an epineurolysis can be additionally performed.  相似文献   
96.
97.
Calcium-oxalate crystal deposition in kidney transplant biopsy specimen led us to investigate the impact of calcineurin inhibitor treatment on urinary excretion of lithogenic and stone inhibitory substances in 53 children after successful kidney transplantation (KTx) receiving cyclosporine A (CsA) or tacrolimus. We compared the values obtained with those of 12 patients with recurrent nephrotic syndrome under CsA and of 6 patients with Rasmussen encephalitis (RE) under tacrolimus therapy. Renal ultrasound examinations were repeatedly performed. Hypocitraturia was found in 69% of patients, with KTx patients having a significantly lower urinary citrate excretion than those receiving calcineurin inhibitors for other reasons. Secondly, we found hyperoxaluria in 35% of patients, again especially in those after KTx. No significant difference in urinary substances was seen comparing CsA with tacrolimus treatment. Urolithiasis was found in one and calcium-oxalate crystal deposition in biopsy specimen of three KTx patients. Calcineurin inhibitor treatment can lead to significant hypocitraturia, especially in patients after KTx receiving the highest dose of medication. Hyperoxaluria is primarily the result of a removal of significant body oxalate stores, deposited during dialysis, but may not be suspected as a specific side effect of calcineurin inhibitor therapy. Both findings can increase the risk for urolithiasis or nephrocalcinosis.  相似文献   
98.
The aim of this in vitro study was to evaluate the depth of effectiveness of erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation on microorganism reduction. From human roots, dentin slices of 100 μm to 1,000 μm thickness were prepared. These specimens were sterilized and then inoculated with 1 μl of Enterococcus faecalis suspension. The backs of the specimens were then irradiated with Er,Cr:YSGG radiation at a pulse energy of 3.13 mJ, delivered at an incidence angle of 5° to the dentin slice surface. A control group was left without irradiation. The remaining bacteria were collected in 1 ml sterilized NaCl solution, serially diluted and seeded in Columbia-Agar plates. Despite the low pulse energy of 3.13 mJ, the Er,Cr:YSGG laser irradiation resulted in significant bacterial reduction up to a dentin thickness of 500 μm (P < 0.05). Scanning electron microscopy (SEM) micrographs of the contaminated and irradiated surfaces showed the absence of a smear layer and opened dentinal tubules.  相似文献   
99.
Anti-infective coatings have been developed to protect the surfaces of cementless implants from bacterial colonization that is known to be a prerequisite for device-related infection. The aim of this study is to investigate the effect of brushite-coated arthroplasty surfaces on human osteoblasts and to evaluate the impact of concomitant exposure to gentamycin. We cultured human osteoblasts (hFOB 1.19) on brushite-coated and uncoated titanium alloy in the presence of gentamycin and analyzed cell function and vitality. Our results show that brushite-coated titanium alloy surfaces supported the function of osteoblasts and the expression of extracellular matrix even in the presence of highly dosed gentamycin. Brushite-coated titanium alloy surfaces supported osteogenic function, indicating that this coating could enhance implant osteointegration in vivo. Concomitant exposure to gentamycin slightly decreased osteoblastic activity in vitro, suggesting that there might also be negative effects in vivo. However, in vivo studies are necessary to validate these in vitro findings.  相似文献   
100.
OBJECTIVE: Effective postoperative analgesia is a critical part of fast-track cardiac surgery. This study compared the postoperative analgesic effect of fast-track anesthesia with remifentanil and spinal morphine and clonidine with that of sufentanil anesthesia followed by patient-controlled administration of intravenous morphine. DESIGN: Prospective, blinded, randomized study. SETTING: Single private institution. PARTICIPANTS: Forty patients selected for coronary artery bypass graft surgery allocated randomly into 2 groups. INTERVENTIONS: General anesthesia was performed with etomidate, isoflurane, cisatracurium, and either remifentanil (0.10-0.25 microg/kg/min) or sufentanil (up to 3.5 microg/kg). In the remifentanil group, patients received spinal morphine (4 microg/kg) and clonidine (1 microg/kg) before induction. Postoperatively, patients in both groups were connected to an intravenous patient-controlled analgesia (PCA) morphine pump that delivered a 1-g bolus with a 7-minute lockout interval. MEASUREMENTS AND MAIN RESULTS: Patients were evaluated for pain on a visual analog scale (VAS), at rest and on deep breathing, and for intravenous PCA morphine consumption during 24 hours. The intravenous PCA morphine 24-hour cumulative dose was lower in the fast-track than in the control group (15.8+/-12.6 v 32.7+/-22.3 mg, p<0.05). Before extubation, VAS scores were higher in the fast-track group, but after they were lower both at rest and during deep breathing. Extubation delay was shorter in the fast-track group (156.5+/-46.1 v 272+/-116.4 minutes, p<0.05). CONCLUSION: The combination of anesthesia with remifentanil and spinal analgesia with morphine and clonidine produces effective analgesia after coronary artery surgery and a rapid extubation time.  相似文献   
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