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81.
To plan an effective management of thoracic vascular malformations, clinicians must have a clear understanding of the anatomy. Although echocardiography and angiography are the leading imaging modalities in patients with congenital cardiovascular anomalies, magnetic resonance (MR) imaging and computed tomography (CT) are valuable noninvasive adjuncts. MR imaging and CT are effective in demonstrating the complex extracardiac morphology and yield helpful information that can change the treatment plan. Although recent reports state the usefulness of multidetector CT (MDCT), in terms of pediatric population, the significance of radiation exposure should be taken into account. Thus, contrast enhanced MR angiography, as a guide in planning surgery, seems to be the best alternative to conventional angiography in the diagnosis of congenital vascular malformations. In this review, the diagnostic features of thoracic vascular malformations in pediatric population are discussed, and, the potential uses of contrast-enhanced MR angiography are emphasized with the retrospective evaluation of imaging findings in 114 examinations.  相似文献   
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Interleukin-12 receptor β1 (IL-12Rβ1) deficiency is the most common form of Mendelian susceptibility to mycobacterial disease (MSMD). We undertook an international survey of 141 patients from 102 kindreds in 30 countries. Among 102 probands, the first infection occurred at a mean age of 2.4 years. In 78 patients, this infection was caused by Bacille Calmette-Guérin (BCG; n = 65), environmental mycobacteria (EM; also known as atypical or nontuberculous mycobacteria) (n = 9) or Mycobacterium tuberculosis (n = 4). Twenty-two of the remaining 24 probands initially presented with nontyphoidal, extraintestinal salmonellosis. Twenty of the 29 genetically affected sibs displayed clinical signs (69%); however 8 remained asymptomatic (27%). Nine nongenotyped sibs with symptoms died. Recurrent BCG infection was diagnosed in 15 cases, recurrent EM in 3 cases, recurrent salmonellosis in 22 patients. Ninety of the 132 symptomatic patients had infections with a single microorganism. Multiple infections were diagnosed in 40 cases, with combined mycobacteriosis and salmonellosis in 36 individuals. BCG disease strongly protected against subsequent EM disease (p = 0.00008). Various other infectious diseases occurred, albeit each rarely, yet candidiasis was reported in 33 of the patients (23%). Ninety-nine patients (70%) survived, with a mean age at last follow-up visit of 12.7 years ± 9.8 years (range, 0.5-46.4 yr). IL-12Rβ1 deficiency is characterized by childhood-onset mycobacteriosis and salmonellosis, rare recurrences of mycobacterial disease, and more frequent recurrence of salmonellosis. The condition has higher clinical penetrance, broader susceptibility to infections, and less favorable outcome than previously thought.  相似文献   
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Background The published results on expression of c-kit in benign and malignant breast tissues vary. Materials and Methods The immunohistochemical expression of c-kit proto-oncogene product in 52 invasive breast cancer tissues and 16 benign breast tumor (fibroadenoma) tissues was studied using anti-c-kit proto-oncogene product antibody. Its expression was evaluated by immunoreactive score (IRS). Results In breast cancer tissues, the mean IRS of c-kit proto-oncogene product expression was significantly increased compared to those of fibroadenoma (3.4 ± 2 and 2.19 ± 1.8, respectively,p = 0.035). The mean IRS of c-kit expression was higher in the group comprising estrogen (ER) positive tumor than in the group of ER negative (4.1 ± 2.1 and 2.7 ± 1.8, respectively,p = 0.012) but no statistically significant relationship was seen between the expression of c-kit proto-oncogene product and other clinicopathological parameters of breast cancer, including histologic type, tumor size, lymph node metastasis, distant metastasis, stage, progesterone receptor, c-erbB-2 expression, menopausal status and age of the patient (p > 0.05). Conclusions Our results show that a high level of c-kit expression occurs frequently in invasive breast cancer, and its expression is associated with ER but unrelated to other clinico-pathological variables.  相似文献   
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PURPOSE: To analyze whether the expression of matrix metalloproteinases (MMPs) and their tissue inhibitors are associated with tumor response to preoperative chemoradiotherapy in rectal cancer patients. METHODS AND MATERIALS: Forty-four patients who had undergone preoperative chemoradiotherapy were evaluated retrospectively. Treatment consisted of pelvic radiotherapy and two cycles of 5-fluorouracil plus leucovorin. Surgery was performed 6-8 weeks later. MMP-2, MMP-9, and tissue inhibitors of metalloproteinase-1 and -2 expression was analyzed by immunohistochemistry of the preradiation biopsy and surgical specimens. The intensity and extent of staining were evaluated separately, and a final score was calculated by multiplying the two scores. The primary endpoint was the correlation of expression with tumor response, with the secondary endpoint the effect of chemoradiotherapy on the expression. RESULTS: Preoperative treatment resulted in downstaging in 20 patients (45%) and no clinical response in 24 (55%). The pathologic tumor response was complete in 11 patients (25%), partial in 23 (52%), and none in 10 (23%). Positive MMP-9 staining was observed in 20 tumors (45%) and was associated with the clinical nodal stage (p = 0.035) and the pathologic and clinical response (p < 0.0001). The staining status of the other markers was associated with neither stage nor response. The overall pathologic response rate was 25% in MMP-9-positive patients vs. 52% in MMP-9-negative patients (p = 0.001). None of the 11 patients with pathologic complete remission was MMP-9 positive. CONCLUSIONS: Matrix metalloproteinase-9 expression correlated with a poor tumor response to preoperative chemoradiotherapy in rectal carcinoma patients.  相似文献   
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This study is designed to determine the placental zinc (Zn) and cadmium (Cd) levels in mothers who were smokers, mothers who were thought to be exposed to air pollution, and mothers who were non-smokers and to investigate the relationship between the expression of placental metallothionein (MT) binding these metals and blood progesterone level. Placental Zn and Cd levels were measured by atomic absorption spectrometry. Presence of placental MT was determined immunohistochemically. Placental changes were examined by light microscope after H&E and PAS staining. Immunohistochemical MT staining of syncytiotrophoblastic and villous interstitial cells were scored as positive or negative. Among the 92 mothers included in the study, 33 were smokers (Group I), 29 had been exposed to air pollution (Group II) and 30 were non-smoker rural residents who had never been exposed to air pollution (Group III). Mean off-spring birth weight of 3198.62+/-380.01 g and mean placenta weight of 561.38+/-111.55 g of Group II were lower when compared with those of other two groups. In Group I, mean placental Cd and Zn were 0.063+/-0.022 microg/g and 39.84+/-15.5 microg/g, respectively, being higher than in other groups. In Group II, mean placental Cd and Zn levels were higher than those of Group III. Blood progesterone levels of subjects in Group I (121 ng/ml) were the lowest of all groups. While the mean count of villi was the highest in Group III; the highest mean count of syncytial knots was in Group II. Thickening of vasculo-syncytial membrane was most prominent in Group I. Similarly, MT staining was positive and very dense in 72.7% (24/33) of cases in Group I (p相似文献   
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