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91.
B M Glaser  R G Michels  B D Kuppermann  R N Sjaarda  R A Pena 《Ophthalmology》1992,99(7):1162-72; discussion 1173
BACKGROUND: Full-thickness macular holes generally cause a significant reduction in visual acuity, due in part to a rim of surrounding neurosensory retinal detachment and retinal thickening. Recent studies have suggested that flattening of this narrow rim of neurosensory detachment can result in improved visual acuity. However, the ability to flatten the neurosensory detachment is limited using current surgical techniques. METHODS: Transforming growth factor-beta 2 (TGF-beta 2) is a recently discovered potent stimulator of wound healing. The authors, therefore, performed a prospective randomized study of 60 patients to determine if the local application of TGF-beta 2 to the edge of the macular hole can reproducibly induce flattening of the surrounding neurosensory detachment. The results of a study designed to determine the effect of a pars plana vitrectomy, fluid-gas exchange, and intravitreal instillation of TGF-beta 2 in eyes with a full-thickness macular hole and reduced visual acuity are reported. RESULTS: After treatment, visual acuity improved 2 lines or more in 5 of 11 eyes treated with 70 ng, in 4 of 12 eyes treated with 330 ng, and in 10 of 11 eyes treated with 1330 ng of TGF-beta 2. In some eyes, hyaluronic acid was added. In these cases, visual acuity improved 2 lines or more in 0 of 9 eyes treated with 70 ng TGF-beta 2, in 2 of 8 eyes treated with 330 ng, and in 4 of 9 eyes treated with 1330 ng. CONCLUSION: Logistic regression analysis demonstrated a statistically significant beneficial effect of TGF-beta 2 on visual improvement (P = 0.003).  相似文献   
92.
We developed and evaluated clinically a series of three vitreoretinal dissection instruments with a constant-diameter shaft and various tip designs including a 90-degree hooked tip, a 130-degree hooked tip, and a blunt-tip right-angle spatula. The instruments, manufactured from a titanium alloy, are lightweight and glare resistant. We have used these instruments interchangeably with other vitreous surgery instruments introduced through a 20-gauge sclerotomy. They facilitate delicate manipulations associated with separation of epiretinal membranes from the inner retinal surface.  相似文献   
93.
We employed pars plana vitrectomy for several different indications in 100 eyes. In 51 eyes, the operation was performed for complications of pholiferative diabetic retinopathy. Improved visual acuity was our only criterion of success, and this varied widely depending on the specific indication forsurgery. Vision improved in all eight eyes undergoing anterior segment reconstruction and in none of three eyes with preoperative retinal detachment complicated by massive vitreous retraction. There was a high incidence of retinal tears complicating the operations in the series (37%). These retinal breaks could usually be closed at the time of the initial operation, and retinal detachment that could not be successfully managed developed in only four eyes.  相似文献   
94.
95.
Computed tomography of cerebral venous angiomas   总被引:1,自引:0,他引:1  
Six cases of venous angioma of the brain, a rare vascular malformation, were studied by means of computed tomography (CT), angiography, and other tests. In each case, angiography demonstrated the typical normal arterial phase and the network of abnormal veins that converge on a single large draining vein. In three cases, the CT scans showed rounded areas of high density not unlike neoplasms in appearance. In the other cases, the CT scan demonstrated the enlarged draining vein only. The CT scan findings, although not specific, may alert the radiologist to the possibility of this lesion and may lead to its demonstration through angiography.  相似文献   
96.
97.
BACKGROUND: A large proportion of older as well as younger patients do not use their hearing aids. Of the younger hearing impaired population, this occurs in the majority of those who do not benefit sufficiently from their hearing aids and, consequently, they face difficulties in their working and social life. SCIENTIFIC QUESTION: Our aim was to evaluate whether a classical hearing aid adjustment is of sufficient predictive value to determine whether adequate rehabilitation in everyday and professional life will occur. METHODS AND RESULTS: A questionnaire was returned by 197 adult hearing impaired patients. Only 108 were using their hearing aids all the time; 57 rarely and 32 never. The main reason for this low rehabilitation rate proved to be inadequate amplification. At the workplace, insufficient speech discrimination came into play. Another important factor was dysacusis induced by specific noise signals. There was an intolerable acoustic feedback in 40% which could not be sufficiently alleviated. Taking these results into account, only about a third of patients were sufficiently rehabilitated. CONCLUSIONS: Proof of effectiveness in a typical audiological testing situation is an important but not a fully reliable predictor for effectiveness in everyday life. Even when hearing aids are shown to be effective with such testing, their application in particular everyday or work situations may be insufficient of even impossible.  相似文献   
98.
99.
BACKGROUND: Does laparoscopic coagulation of the uterine blood supply decrease blood loss compared with transvaginal ligature of the uterine vessels? METHODS: Intra- and postoperative data of 446 patients undergoing laparoscopic-assisted vaginal hysterectomy at the Department of Gynecology, University of Jena, between 1998 and 2001 were analysed. In 213 patients the uterine blood supply was transected laparoscopically at the origin of the uterine vessels (LAVH type II) and in 233 patients (LAVH type I) transvaginally. RESULTS: Patients in both groups were comparable with respect to median age, Quetelet index, and parity. The drop of hemoglobin between the preoperative day and postoperative day 3 was 0.8 mmol/l or 0.6 mmol/l for LAVH type I without or with BSO vs 0.3 mmol/l or 0.4 mmol/l for LAVH type II without or with BSO (p = 0.001), respectively. Median operative time was similar for both techniques: LAVH type I 136 min or with BSO 128 min vs LAVH type II 126 min or with BSO 131 min. The weight of the removed uteri was significantly lower in LAVH type I vs type II (220 vs 270 grams), but similar when LAVH was combined with BSO (160 vs 178 grams). The rate of intraoperative complications was 2.2% vs 0.9% between LAVH type I or II (n.s.), but 9% vs 3.3% for overall postoperative complications (p = 0.01). CONCLUSIONS: Laparoscopic coagulation of the uterine blood supply at the origin of uterine vessels is a safe technique which minimizes blood loss in LAVH. In patients with a low preoperative hemoglobin value this technique is indicated.  相似文献   
100.
PURPOSE: Recognition of hereditary nonpolyposis colorectal cancer (HNPCC)-related endometrial carcinoma from sporadic carcinoma by histologic features as compared with colonic cases. STUDY DESIGN: Case-control study. METHODS AND MATERIALS: From the files of the Nijmegen Hereditary Cancer Clinic, HNPCC-related (n = 6) endometrial and colorectal (n = 18) carcinomas were selected. For every HNPCC-related tumor, 2 sporadic control cases were included. The tumors were evaluated for the following 7 pathologic features: tumor differentiation, T-stage, growth pattern, presence of Crohn-like lymphoid reaction, mucinous differentiation, presence of lymphangioinvasive growth, and the amount of tumor-infiltrating lymphocytes. RESULTS: HNPCC-related endometrial carcinomas were significantly more often poorly differentiated (83% versus 27%), more often showed the presence of a Crohn-like lymphoid reaction (100% versus 13%) and lymphangioinvasive growth (67% versus 0%), and high number of tumor-infiltrating lymphocytes were more often present (100% versus 36%) compared with sporadic endometrial carcinomas. The differences between HNPCC and sporadic colorectal cancer specimens were less discriminating. CONCLUSIONS: HNPCC-related endometrial carcinomas are characterized by poor differentiation, more frequent Crohn-like lymphoid reaction, lymphangioinvasive growth and more tumor-infiltrating lymphocytes. These features therefore might form the basis for selecting patients for counseling in a hereditary cancer clinic or testing for microsatellite instability or mutation analysis of mismatch repair genes, especially when they are of relatively young age.  相似文献   
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