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91.
The aim of this study was to assess the radiologic and clinical outcome when beta-tricalcium phosphate is used as a bone graft substitute to backfill the fibular defect that is created by harvesting the fibula. Fourteen patients who had fibula resections to be used as bone grafts for bone tumor resections were assessed radiographically. Callus formation bridging the beta-tricalcium phosphate was seen in 12 of 14 patients at an average of 1.4 months after surgery. In these 12 patients the beta-tricalcium phosphate mostly was absorbed and replaced by newly formed bone at an average of 9.3 months after surgery. In all children, beta-tricalcium phosphate was replaced by newly formed bone at an average of 3.2 months after surgery. Only one adult patient had complete regeneration of the fibula. Few patients had continuity between the regenerated fibula and the native fibula. In one patient in whom free vascularized fibula was harvested, regeneration of the fibula was not observed. Clinical functional outcome was not correlated with successful fibula regeneration and union with the native fibula, as determined using radiographs. The results of the study suggest that, in children, regeneration of the fibula by implanting beta-tricalcium phosphate into a bone defect can reduce morbidity of the fibula harvest sites.  相似文献   
92.
PURPOSE: The indications for repeat prostate biopsy for persistently increased prostate specific antigen (PSA) in men with prostate cancer never detected on previous biopsy are not clear. In this study we determined that PSA adjusted for transition zone (TZ) epithelial volume is the most powerful predictor for detecting prostate cancer on repeat biopsy. MATERIALS AND METHODS: Repeat prostate biopsies including additional TZ cores were performed in 75 men with PSA between 4.0 and 10.0 ng/ml. TZ epithelial volume was calculated by multiplying TZ volume by the percent of epithelium, which was measured by morphometric analysis using image analysis computer software. RESULTS: Prostate cancer was detected on repeat biopsy in 19 of the 75 patients. Patients with prostate cancer had a significant smaller percent area of epithelium or glandular lumen than those without cancer. In patients without prostate cancer TZ epithelial volume significantly correlated with total PSA. According to ROC analysis PSA adjusted for TZ epithelial volume had the greatest AUC for cancer detection (0.879). This parameter was able to avoid more than 90% of unnecessary repeat biopsies with 90% sensitivity. Multiple logistic regression analysis showed that PSA complex adjusted for TZ epithelial volume was the significant independent predictor of cancer. CONCLUSIONS: PSA adjusted for TZ epithelial volume is the most powerful predictor of cancer in men who have undergone previous negative prostate biopsies and in whom PSA remains between 4.0 and 10.0 ng/ml.  相似文献   
93.
We encountered a 69-year-old man with lung adenocarcinoma and pulmonary sequestration. The cancer lesion was located in the left upper lobe, with sequestration of the left lower lobe. Left upper lobectomy was performed after induction chemoradiotherapy, but the sequestered lung lobe was preserved because the preoperative respiratory function was poor. Preservation of the sequestered lung during surgery for lung cancer should be considered in patients who have poor respiratory function and no signs of respiratory infection.  相似文献   
94.
BACKGROUND: Major pulmonary resection with systematic node dissection (SND) for early lung cancer by video-assisted thoracic surgery (VATS) is performed in many institutes, but the feasibility of SND for early lung cancer by VATS remains controversial. The aim of this study was to elucidate the feasibility and safety of SND by VATS. METHODS: Three hundred fifty patients with clinical stage I lung cancer who underwent pulmonary major resection with SND between 1998 and 2003 were enrolled in this study. Of these patients, 191 (VATS group) underwent pulmonary resection with SND by VATS; 159 patients (open thoracotomy [OT] group) did so through anterolateral thoracotomy. The clinical and pathologic data, including the number of dissected nodes in each nodal station, of the 2 groups were compared to evaluate the feasibility of SND by VATS. RESULTS: Pathologic data showed that, in the VATS group, more patients had adenocarcinoma (P = .0078) and fewer patients had advanced factors than the OT group. The greatest tumor diameter was 24.5 mm and 29.6 mm in the VATS group and OT group, respectively (P < .0001). The total number of mediastinal nodes dissected in right upper lobectomy plus right middle lobectomy (RUL+RML), right lower lobectomy (RLL), left upper lobectomy (LUL), and lower left lobectomy (LLL) also did not differ between the 2 groups. The total number of mediastinal nodes dissected in RUL+RML, RLL, LUL, and LLL was 19.7 in the VATS group versus 22.0 in the OT group (P = .122), 23.4 versus 21.0 (P = .241), 14.8 versus 17.5 (P = .123), and 18.8 versus 15.8 (P = .202), respectively. The number of dissected nodes in each nodal station in RUL+RML, RLL, LUL, and LLL was similar between the 2 groups. Operative mortality, morbidity, or recurrence did not differ between the 2 groups. CONCLUSIONS: With regard to the number of dissected nodes, SND by VATS was not inferior to that of OT. SND by VATS is technically feasible and safe, and seems acceptable for clinical stage I lung cancer.  相似文献   
95.
A home screening device, LT-200, can record data on both breathing conditions and body positions during sleep for up to 3 consecutive days in patients with obstructive sleep apnea (OSAS). We investigated the usefulness of the LT-200 device for follow-up of OSAS. Eighteen patients (age 51.0 +/- 10.8 years, mean +/- SD) were enrolled in this study. Standard polysomnography (PSG) was performed on all patients. The number of apnea/hypopnea episodes per hour (apnea/hypopnea index: AHI), the total time that nocturnal oxygen saturation was < 90% (oxygen desaturation time: ODT), and the minimum oxygen saturation during sleep (lowest Spo2) were calculated. We used the LT-200 and PSG to evaluate any improvement in the data obtained after auto-continuous positive airway pressure (auto-CPAP) therapy. AHI was also measured using the LT-200 in three sleep positions to evaluate the efficacy of the lateral position. AHI, ODT, and lowest Spo2 values did not differ significantly between the PSG and LT-200 recordings on the control and therapy nights. The LT-200 recordings showed that AHI, ODT, and lowest Spo2 tended to be better on the second night of auto-CPAP therapy than on the first. AHI was significantly lower in the right and left lateral sleep positions than that in the supine position. Our findings suggest that since the LT-200 device provides important information about the severity of OSAS, the efficacy of auto-CPAP therapy, and body position under unattended conditions in the home. It may prove to be a useful tool for following up patients.  相似文献   
96.
OBJECTIVES: Given that criteria for nasal surgery in individuals with obstructive sleep apnea syndrome (OSAS) have not been proposed, we investigated the effectiveness of nasal surgery for CPAP failure in patients with both severe OSAS and nasal obstruction. PATIENTS AND METHODS: Conventional nasal surgery was performed in 12 patients who were refractory to treatment by CPAP. The subject group consisted of 12 males (mean age, 54.2 +/- 9.2 years; range 39-66 years). The effect of nasal surgery was evaluated with data from preoperative and postoperative polysomunography. The nasal resistance value was first deduced to determine which OSAS patients with CPAP failure should undergo nasal surgery, compared to control values. RESULTS: Nasal surgery resulted in a significant decrease in nasal resistance, as measured by rhinomanometry, from 0.57 +/- 0.31 Pa/cm3 /sec to 0.16 +/- 0.03 Pa/cm3/sec and rendered all patients tolerant to CPAP. In addition, the lowest nocturnal oxygen saturation significantly increased from 68.3 +/- 12.1% to 75.3 +/- 7.1% after surgery. Subjectively, Epworth sleepiness scale (ESS) significantly decreased from 11.7 +/- 4.1 to 3.3 +/- 1.3 after surgery, but the number of apnea and hypopnea episodes per hour did not change significantly. In five patients, for whom it was possible to perform a CPAP titration before nasal surgery, the value decreased significantly from 16.8 +/- 1.1 to 12.0 +/- 1.9 cmH2O. The bilateral nasal resistance of the 410SAS patients with CPAP therapy (control group) was 0.24 +/- 0.11 Pa/cm3/sec. The cut off value for differentiation between CPAP failure patients and control group was determined as 0.38 Pa/cm3 /sec. CONCLUSION: Increased nasal resistance is a determinant of CPAP failure, and the surgical correction of severe nasal obstruction should thus be considered to facilitate treatment of OSAS patients with CPAP.  相似文献   
97.
Early-onset sarcoidosis (EOS) and inheritable Blau syndrome (BS) share characteristic clinical features of juvenile-onset systemic granulomatosis syndrome that mainly affects skin, joints, and eyes. However, no direct evidence has been shown for the possible common origin of these 2 diseases. Recent discovery of CARD15 mutations in BS families encouraged us to investigate similar CARD15 mutations in EOS patients. Among 10 EOS cases retrospectively collected in Japan, heterozygous missense mutations were found in 9 cases; 4 showed a 1000C>T (R334W in amino acid change) that has been reported in BS, 4 showed novel 1487A>T (H496L), 1538T>C (M513T), 1813A>C (T605P), and 2010C>A (N670K), and 1 case showed double 1146C>G (D382E)/1834G>A (A612T) mutations on different alleles. All 6 of these variants of CARD15 showed increased basal nuclear factor (NF)-kappaB activity. These findings indicate that the majority of EOS and BS cases share the common genetic etiology of CARD15 mutations that cause constitutive NF-kappaB activation.  相似文献   
98.
Troglitazone and D-chiroinositol have been shown to exert antidiabetic effects by either potentiating or mimicking insulin action. We studied whether pretreatment with these compounds can prevent the deleterious effects of glucosamine on insulin action that may play an important role in hyperglycemia-induced insulin resistance. Normal Wistar rats were pretreated with troglitazone (100 mg/kg/d), D-chiroinositol (100 mg/kg/d), or placebo (saline) for 7 days. Glucosamine (50 micromol/kg/min) was then infused for 210 minutes, and a euglycemic glucose clamp was performed during the last 120 minutes. Pretreatment with troglitazone or D-chiroinositol had no effect on fasting plasma glucose or insulin or basal hepatic glucose output (HGO). Under the euglycemic-hyperinsulinemic (956+/-93 pmol/L) clamp condition, HGO in glucosamine-infused placebo-treated rats was not suppressed, but instead was increased over the basal level, indicative of hepatic insulin resistance. In contrast, HGO failed to increase during glucosamine infusion in rats pretreated with troglitazone but was not normally suppressed. This may indicate a partial improvement in the hepatic insulin resistance. D-Chiroinositol pretreatment had no effect on the glucosamine-induced increase in HGO. The glucose disposal rate (GDR) was 25% lower in rats infused with glucosamine versus saline-infused rats (25.5+/-2.5 v 34.1+/-2.0 mg/kg/min), indicative of peripheral insulin resistance. Pretreatment with D-chiroinositol (34.5+/-2.3 mg/kg/min) prevented the glucosamine-induced decrease in the GDR, indicating an improvement in peripheral insulin resistance. Troglitazone (25.2+/-3.3 mg/kg/min) was without effect. In conclusion, (1) in normal control rats, glucosamine infusion induced hepatic and peripheral insulin resistance; (2) D-chiroinositol, but not troglitazone, pretreatment prevented glucosamine-induced peripheral insulin resistance; and (3) troglitazone, but not D-chiroinositol, partially blocked the glucosamine-induced hepatic insulin resistance. D-Chiroinositol may provide a novel pharmacological approach to hexosamine-induced peripheral insulin resistance.  相似文献   
99.
OBJECTIVE: Definitive hematopoiesis starts in the aorta-gonad-mesonephros (AGM) region during mouse development and remarkably expands in the liver at a later stage of ontogeny. gp130 is a signal transducing receptor component shared by all the IL-6 family cytokines, whose gene ablation in mouse results in the significant reduction in the fetal liver hematopoiesis. The present study aims to evaluate the role of gp130 signaling in the fetal mouse AGM hematopoiesis. METHODS AND MATERIALS: Mouse AGM regions from the wild-type and gp130-deficient mice on embryonic day 11.5 were dissociated and cultured with a mixture of cytokines, including one which activates gp130. Wild-type human gp130 and its mutant constructs were introduced into cultured gp130-deficient AGM cells using retrovirus system. To further analyze gp130 downstream signaling, a dominant-negative mutant of STAT3 was also introduced. RESULTS: The gp130 deficiency in the culture of fetal mouse AGM cells resulted in the failure of the expansion of the c-kit(+), Sca-1(+), and lineage markers(-) population. Such failure was rescued by introduction of a wild-type gp130 expression construct but not its mutant constructs having no ability to activate STAT3. In the normal AGM cell culture, introduction of a dominant-negative form of STAT3 in which Y(705) was changed to phenylalanine suppressed the expansion of hematopoietic cell colonies. CONCLUSION: gp130 plays an indispensable role in the expansion of hematopoietic precursor cells in the fetal mouse AGM. In particular, the activation of STAT3 by gp130 is found to be important in this process.  相似文献   
100.
In this study, we compared the impact of health problems (HPs) on everyday activities and depressive symptoms between middle-aged and older adults. We also examined what type and source of social interactions moderate the noxious effects of HPs. Longitudinal analyses of data with 1,802 Japanese community-dwelling adults indicated that HPs were significantly related to (a) an increase in depressive symptoms among middle-aged adults and (b) a decline in everyday activities among older adults. The former was buffered by emotional family support, whereas the latter (b) was buffered by instrumental family support and, surprisingly, by negative interactions with family. In contrast, social interactions with other friends and acquaintances did not show any moderating effect.  相似文献   
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